UNIVERSITY OF WOLVERHAMPTON

SCHOOL OF ENGINEERING AND THE BUILT ENVIRONMENT

Visualisation Development for The Virtual Construction Site

David Heesom and Lamine Mahdjoubi

This research is funded by the Engineering and Physical Sciences Research Council’s research programme award no GR/N00876 as part of the Innovative Manufacturing Initiative

Visualisation Development for The Virtual Construction

Site Visualisation Development David Heesom and Lamine Mahdjoubi

Published by School of Engineering and the Built Environment University of Wolverhampton Wulfruna Street Wolverhampton WV1 1SB United Kingdom First Published April 2002 ISBN: 1-86162-004-7 All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronically or mechanically, photocopying, recording or otherwise without the written permission of the publisher and the copyright holder. Requests for such permission should be made to the publisher in writing to the above address. All information was correct at time of publication. © D. Heesom and L. Mahdjoubi 2002

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The Virtual Construction Site Visualisation Development

Executive Summary This document presents a report on the software developed for the Visualisation Development for the Virtual Construction Site (VIRCON) project. The report reviews the rationale behind software development and clearly identifies how the tools integrate with the other programs of the VIRCON system. The aim of the development was to be able to visualise in 4 dimensions not only the construction process, but also the space used throughout the construction phase. During the development stage, issues were raised that required further exploration. In order to resolve these issues, software tools were developed that allowed the visualisation of these specific spaces and provided this information to other tools in the VIRCON system to assist the spatial analysis. The following presents a brief summary of the motivation for each developed software tool: 1. In order to assign resources with their spatial requirements, a library of resources

is required. Resource Manager (ResourceMan) allows the planner to generate a library of resources that can be included as required into the construction schedule. This library is divided into General Resources (human and general resource) and Plant Resources (plant and temporary objects). The principle underlying the tool is the generation of an extensible library of resources that requires space to operate on the construction site.

For each of the resources, stored in the generated library, various spatial attributes, (e.g. work area required), are assigned and stored. This information can then be read directly by Microsoft Project and used with standard resource allocation tool. The objects generated and stored as plant and temporary works are also assigned spatial attributes. For each of the objects created in the library the spatial requirements are stored. These can be read by PlantMan to allow the inclusion of plant into the weekly spatial analysis.

2. The development of a full spatial analysis of the construction site during any stage

of the process, plant and temporary work objects have to be taken into account. Plant Manager (PlantMan) provides the construction planner with the ability to utilise drag and drop technology to position plant and temporary work objects onto dynamically generated weekly site layouts.

PlantMan uses the geometric temporal information stored in the VIRCON database to automatically generate weekly site plans, showing construction products that are both complete and under construction. PlantMan also uses information stored in the resource library generated by ResourceMan software. The library of plant / temporary works objects is loaded into PlantMan and can be assigned to the generated weekly layouts, using the drag and drop principal. In addition to assigning these workspaces, PlantMan also present the user with the ability to assign dynamic objects to the construction site. The Interactive Path Assigner within PlantMan allows the planner to create route paths for specific plant objects for any given week during the construction phase. This information is necessary to facilitate a more realistic dynamic site visualisation.

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PlantMan produces report and geometric information for use by the planner. A report can be generated to highlight the amount of space used by construction plant during any week of the project. Geometric information is also output from PlantMan for use by the developed AreaMan software. The weekly layout of the construction site, including plant space used, provides a mark up plan for use with AreaMan.

3. Conflicts that exist between temporary works and Plant can have an adverse

affect on productivity. In order to detect conflicts in 4 dimensions between constructed entities and temporary works, Clash Manager (ClashMan) was developed. This tool allows the detection of conflicts between the building product and temporary works in 4 dimensions. Detected conflicts between objects are stored and reported to the planner either in a report format or in a graphical format through the 4D visualisation. Collision information is directed to the 4D visualisation software allowing the planner to view potential collisions in 4D, in realtime, allowing a greater awareness of potential problems.

4. Visualising the construction in 4 dimensions provides the planner with a more

intuitive view of the construction sequence. Product Space Visualiser (SpaceVis) is an interactive 4D-viewing tool for the VIRCON System. This tool allows the planner to view and interact with the construction site, during any stage of the construction process.

SpaceVis is an independent software tool that generates virtual reality objects to represent both the construction product and site space utilisation. This information is read from the VIRCON database, the developed PlantMan tool and the Critical Space Analysis, generated by the SpaceMan software. The construction planner can use this software to view a complete real time visualisation of the construction site, during any stage of the schedule. The 4D visualisation produced is also interactive and as such the planner can interact with the simulation querying intelligent objects in the simulation and obtaining information about their location, the activity they relate to, and any potential time-space conflicts that exist.

In summary, the software tools assist the construction planner in developing a complete spatial visualisation of the construction site. Each of the tools has been developed as a standalone software application, requiring no proprietary software and hence reducing the cost to the construction company. The software tools have been developed to fully integrate with the other VIRCON prototypes and require minimal technical input from the planner. Collaboration between all parties in the construction process is key to the successful delivery of a project and so each of the tools has been developed with the capability to become Internet enabled. Each package has the ability to read database information from a remote site and the use of VRML to present an interactive 4D simulation. This enables the viewing of the simulation over the Internet.

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The overall rationale for software development was guided by the following criteria: • Ease of use: It was decided to select a browser-based system with real-time

communication capability. This enables planners to interact with the various programmes through a VRML interface. In addition, this technology allows planners to access and display data in real-time, making software use more interesting and intuitive.

• Interactivity: It was deemed important to allow a high level of interactivity to allow users to tailor presentations to their own exact personal needs.

• Collaboration and easy data sharing: Collaboration is considered as key to software development. As all the developed prototypes are web enabled, they allow data sharing and concurrent interaction between various stakeholders. Any data that Internet infrastructure can be used by the developed software and no special applications are needed

• Adaptability: Adaptability is also central to software development. The flexibility of some tools (such as ResourceMan) enables planners to adapt the programme to suit their own requirements.

• Extensibility: As the prototypes are web-enabled, they allow easier integration of emerging Internet technologies. In addition, they enable users to develop and extend the programme.

• Software proprietary independence: It was judged important to deliver tools, which are independent of proprietary developers. As a result, of the adoption of the Web-technology, the support cost for such a platform is reduced.

• Integration: Integration with other applications and databases was also considered as a key component in software development.

• Automation: Automation of certain routines and data was deemed necessary to make easier and quicker for planners to explore, analyse and display relevant information.

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Table of Contents 1.0 Introduction ........................................................................................................................1

1.1 General Introduction.........................................................................................................1 1.2 Structure of Report ...........................................................................................................1

2.0 Research Methodology .......................................................................................................3 2.1 Background.......................................................................................................................3

2.1.1 Mechanical and Electrical Trades..............................................................................3 2.1.2 Groundwork Operations ............................................................................................5

2.2 Aims and Objectives.........................................................................................................8 2.3 Previous Research Initiatives............................................................................................9

2.3.1 4D Visualisations.......................................................................................................9 2.4 Development Approach..................................................................................................10

3.0 System Development.........................................................................................................12 3.1 Introduction ....................................................................................................................12 3.2 VIRCON Resource Manager (ResourceMan) ................................................................13

3.2.1 Overview .................................................................................................................13 3.2.2 Software Rationale ..................................................................................................13 3.2.3 Information Flow.....................................................................................................13 3.2.4 User Interface and User Interactions .......................................................................14

3.3 VIRCON Plant and Temporary Resource Manager (PlantMan)....................................16 3.3.1 Overview .................................................................................................................16 3.3.2 Software Rationale ..................................................................................................16 3.3.3 Information Flow.....................................................................................................16 3.3.4 User Interface and User Interactions .......................................................................18

3.4 VIRCON Temporary Works Clash Identifier (ClashMan) ............................................23 3.4.1 Overview .................................................................................................................23 3.4.2 Software Rationale ..................................................................................................23 3.4.3 Information Flow.....................................................................................................23 3.4.4 User Interface and User Interactions .......................................................................25

3.5 VIRCON 4D Virtual Reality Project and Space Simulator (SpaceVis) .........................26 3.5.1 Overview .................................................................................................................26 3.5.2 Software Rationale ..................................................................................................26 3.5.3 Information Flow.....................................................................................................26 3.5.4 User Interface and User Interactions .......................................................................29

4.0 Integration with VIRCON Software...............................................................................34 4.1 Overview ........................................................................................................................34 4.2 Software Integration .......................................................................................................34 4.3 VIRCON System Integration..........................................................................................35

5.0 Conclusions........................................................................................................................37 5.1 Overview ........................................................................................................................37 5.2 Limitations......................................................................................................................37

5.2.1 ResrouceMan ...........................................................................................................37 5.2.2 PlantMan..................................................................................................................38 5.2.3 ClashMan.................................................................................................................38 5.2.4 SpaceVis ..................................................................................................................38

5.3 Recommendations for future development.....................................................................39 6.0 References..........................................................................................................................40

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Table of Figures Figure 1: Mechanical and Electrical Project Schedule...............................................................3 Figure 2: Resource breakdown for the M&E work packages ....................................................4 Figure 3: Mechanical and Electrical space usage.......................................................................4 Figure 4: Additional Equipment required for M & E Tasks.......................................................5 Figure 5: Work / Spatial Breakdown Structure for piling activity .............................................6 Figure 6: Project Schedule for Groundwork’s Operations .........................................................7 Figure 7: Site and Piling layout for UCL Hospital .....................................................................8 Figure 8: ResourceMan Information Flow ...............................................................................14 Figure 9: ResourceMan start up Interface ................................................................................14 Figure 10: Resource attributes input dialogue..........................................................................15 Figure 11: PlantMan Information Flow....................................................................................17 Figure 12: Level Datum Assignment........................................................................................18 Figure 13: Product to Level Assigner.......................................................................................19 Figure 14: PlantMan Main User Interface................................................................................20 Figure 15: Drag and Drop Plant Objects from the Resource Library.......................................21 Figure 16: Assigning Dynamic Movement Paths for Plant Objects.........................................21 Figure 17: Extract from Plant Space Usage Report..................................................................22 Figure 18: DXF Site Layout Generation Routine.....................................................................22 Figure 19: ClashMan Information Flow...................................................................................24 Figure 20: ClashMan User Interface ........................................................................................25 Figure 21: Example of collision detection Report....................................................................25 Figure 22: SpaceVis Information flow .....................................................................................27 Figure 23: VRML Generation Process .....................................................................................28 Figure 24: Animated path generation .......................................................................................29 Figure 25: Selection of monitoring date for 4D Simulation.....................................................30 Figure 26: 4D VRML view of construction products...............................................................31 Figure 27: 4D VRML View of Plant Spaces assigned using PlantMan...................................31 Figure 28: Plant Space attributes shown in 4D information window.......................................32 Figure 29: 4D Simulation Control Panel ..................................................................................32 Figure 30: Microsoft Project viewing Window........................................................................33 Figure 31: Software integration................................................................................................34 Figure 32: VIRCON System information flow ........................................................................35 Figure 33: VIRCON Analysis configuration............................................................................36

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1.0 INTRODUCTION 1.1 General Introduction Building on the work undertaken in Task 2 of the VIRCON project, Task 7, Visualisation Development, uses the information stored in the VIRCON database to develop a real time simulation of the construction process. Initially the task focused on the development of simulations including the specialist trades of Mechanical and Electrical and Groundwork operations. This was an area identified by Riley (1998) who recommended that the modelling of 4D construction operations be focused on HVAC, Electrical, Plumbing, Fire Protection, Carpentry and Curtain Wall operations as these areas caused many problems during construction. Research into these areas of the construction process was undertaken using information provided by Asea Brown Boveri (ABB) Consultants, who were responsible for the Mechanical and Electrical work package on the Teesside School of Health Project and BCJV, a joint venture between Amec Capital Projects, Balfour Beatty and Haden Young, who are undertaking the groundwork operations for the University College London new Hospital (UCLH) development. To consolidate this research, work was also carried out with Stent foundations to develop work breakdown structures and general overviews of groundwork operations and how these could be best visualised. This task seeks to develop a visualisation tool that allows building products and processes to be viewed in a two and three-dimensional format. In addition to visualising the construction process in 4 dimensions, the suite of tools developed also enables graphical input and output for the VIRCON space analysis programs AreaMan and Spaceman. 1.2 Structure of Report This report presents the development process of software developed for task 7 of the VIRCON project. Section 2 of this report presents the background to development and also presents a brief overview of previous work undertaken in the area of visualisation simulation. From these findings a research approach is presented which forms the basis of the software tools developed during the development process. Section 3 presents the system development of the 4 key tools developed to assist the visualisation development, ResourceMan, PlantMan, ClashMan and SpaceVis. A detailed technical review is presented demonstrating the information flow through each of the systems and the user interactions. Section 4 highlights the integration of the tools developed under this task. In addition to reviewing how each of the tools interacts with each other, this section also illustrates how the tools developed interact with the other software elements of the VIRCON system. Section 6 presents conclusions and highlights any potential limitations of the developed tools. This section also demonstrates areas of future research and

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methods to enhance the software tools developed to provide more robust simulations to be generated.

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2.0 RESEARCH METHODOLOGY 2.1 Background In order to develop a methodology for software development, this task initially focused on groundwork operations and service installations. These are deemed to provide the most challenging area of spatial analysis for the construction planner. Additionally, it identifies and documents the Work Breakdown Structures for various groundwork and M&E operations. 2.1.1 Mechanical and Electrical Trades In order to develop a greater understanding of the Mechanical and Electrical operations, meetings were held with ABB Consultants. ABB were responsible for the M&E operations on the Teesside School of Health building. Relevant information was obtained on the Work Breakdown Structure and the Equipment used during each stage of the project. The project plan for the M&E aspect of the work can be seen in Figure 1.

Figure 1: Mechanical and Electrical Project Schedule

Daily labour records were kept by ABB depicting the number of operatives for each of the tasks shown on the project plan and also the additional temporary works objects required. Using this information, a review was compiled to show the number of operatives and equipment used for each task on a daily basis. This resource information was input into the VIRCON database to assist in the visualisation development. An extract from the compiled personnel / task data is shown in Figure 2.

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Figure 2: Resource breakdown for the M&E work packages

Using this information, an initial space usage plan was compiled. This involved drawing workspaces onto the plans, showing the overall site and the mechanical and electrical constructed products. An illustration of these plans can be seen in Figure 3.

Figure 3: Mechanical and Electrical space usage

These plans took into consideration the labour used for each task within the Mechanical and Electrical work packages. Following consultation with the M&E contractors, their method for undertaking the work was taken into account. Whilst this provided an initial insight into how the work was undertaken in this project, it only took into account the direct labour required for each task. This data did not take into account the numerous supporting objects that require space in order to undertake the task. A list of the equipment used by the contractors to undertake each task can be seen in Figure 4.

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Figure 4: Additional Equipment required for M & E Tasks

The research undertaken with ABB Consultants demonstrated that not only does labour have to be taken into account during space analysis but supporting plant and temporary works play a vital role in analysing space consumption. For many mechanical and electrical tasks supporting plant is required, for example scaffold towers and telescopic trucks. These factors are required to be taken into account for both the generation of a comprehensive space analysis and visualisation. 2.1.2 Groundwork Operations In order to develop a broad knowledge of groundwork processes, meetings were held with Stent foundations and BCJV personnel in order to develop a work breakdown for various groundwork operations that included the spatial requirements during each stage. From the meetings it is apparent that in addition to labour, plant equipment and safety areas are also of great significance in groundwork operations. Following the meetings a breakdown was developed in conjunction with various groundwork engineers to depict the time requirement and the spatial requirement at each stage. A typical example of a breakdown for the piling process was developed. Approximate layouts were generated for each stage of the of the process and these can also be seen in Figure 5

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Task Approx Time

Resources Required

Approx Spatial Layout

Clear Site Various Plant / Human Attach boring rig to C50 crane

15mins Plant / Human

Bore to a depth of 3m approx.

25mins Plant

Replacing boring rig with vibrating rig

15mins Plant / Human

Drive pile sleeve into ground to depth of approx. 20m

45mins Plant

Replace vibrating rig with boring rig

15mins Plant / Human

Bore out earth from sleeve

30mins Plant

Lower in pile skin and prefabricated steel cage

10mins Plant / Human

Concrete delivered to site

- Plant

Pour concrete into pile skin

20mins Plant / Human

Remove pile sleeve either by vibrating or screw as above

20mins Plant

Back fill earth to pile sleeve

15mins Plant

Wait for concrete to cure

Various None

Construct pile cap

Various Plant / Human / Temporary

Works

Figure 5: Work / Spatial Breakdown Structure for piling activity

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In order to further develop and understanding of the groundwork processes a case study was used. Work was undertaken with BCJV to obtain detailed information relating to the piling and groundwork operations for the UCL Hospital development. The methodology employed for groundwork operations varied in many respects to the one used for the mechanical and electrical trades. The task breakdown for groundwork operations relates to a group of objects (for example a group of piles) rather than the construction of one product. This resulted in larger ‘execution space packages’ being assigned to tasks. As seen in Figure 5, the extract of the project plan for placing piles is broken down into packages and these packages relate to groups of piles located by the structural grid lines.

Figure 6: Project Schedule for Groundwork’s Operations

For each of the tasks on the construction schedule plant and temporary works objects were required for the successful execution of the task. Additionally safety areas were required around the site of the work package both during the task execution and after execution, for example for concrete curing. In addition to the execution space required by plant objects it also became apparent from the study that during work processes paths were of vital importance. Particularly on the UCLH case study the site was of a constrained nature and so access paths for plant was important. Figure 7 illustrates the layout of the piles for the UCL hospital development.

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Figure 7: Site and Piling layout for UCL Hospital

The study of groundwork operations and their spatial requirement reinforced the theory postulated for mechanical and electrical trades. In order for a complete spatial analysis to be undertaken, the space requirements of both plant objects and temporary works are required to be observed. Due to the nature of groundwork operations considerable plant is used and this requires both execution space and hazard areas around the plant. Additionally temporary works are required for example for pile cap construction. 2.2 Aims and Objectives The aim of the task is the production of a prototype system to allow the visualisation of both the constructed product and the space required during the construction phase. This system would build on previous 4D systems as it would enable the reading of geometry from the VIRCON database and would allow the results of critical space analysis calculations to be viewed in both 3 and 4 Dimensions in a realtime interactive environment. Initially the system was envisaged to produce visualisations of specialist trade operations, however these processes could not be realistically visualised without the concurrent visualisation of the whole building. The research into specialist trade operations highlighted that plant and temporary works are required for construction operations. This is true not only for groundwork and service installations but also for general construction tasks. In order to achieve the aim of developing a visualisation system various objectives were defined. These objectives included:

• The development of a Real Time visualisation system that would provide the user with a 4D simulation of the construction process.

• The ability of the developed system to operate independently of any

proprietary software systems, whilst also providing an intuitive and easy to use system.

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• The development of the use of Space-Templates discussed by Heesom and Mahdjoubi (2002b) that would allow a more accurate 4D representation of the construction site. These would allow the planner to input space required by plant and temporary works objects.

• The ability to incorporate paths into the simulation. Research showed that

paths are of vital importance to the construction processes in particular specialist trade operations and are required to be incorporated into the simulation.

2.3 Previous Research Initiatives 2.3.1 4D Visualisations Producing a 4D simulation involves linking a 3D graphic model to a construction schedule through a third party application (McKinney et al 1996). As documented by Heesom and Mahdjoubi (2002a) various research efforts have been focused on the delivery of the 4D Visualisation of construction projects. The principle concept of 4D Simulations has been documented in the manufacturing industry for some considerable time to present the production process over time and has enabled the reduction of cycle times considerably (Jenkins, 1998). This virtual assembly planning allows the user to check and highlight any potential problems or conflicts in the virtual domain before they actually occur in the real world (Korves et al., 1996). One of the first initial research initiatives in the area of 4D CAD for the Construction industry was reported by Martin Fischer in 1996. Since then various projects have been undertake at the Centre for Integrated Facility Engineering (CIFE) at Stanford University, USA. These projects include 4D Annotation (McKinney 1998), evaluating construction schedule logic (Koo et al.,1998), Construction Method Models (Aalami, 1998) and Time Space conflict Analysis (Akinci et al., 1998). Another early prototype to explore the area of 4D CAD for construction was the Virtual Reality Planner (VR Planner), a 4D simulation tool developed at the University of Strathclyde. The system aims to provide a virtual reality interface to allow the user to visualise the various stages of the construction project utilising the Superscape Virtual Reality Toolkit software package (Retik, 1995). Normally 4D simulations are considered once the design has been substantially completed and emphasis turns to the sequencing of the product assembly (Tommelein, 2000). 4D CAD at the present time has been described as ‘techno-construction-centric’ (Barrett, 2000) whereby the thrust of work is based on the technological issues with emphasis on the construction phase. It is also being suggested that project managers and planners that use 4D simulations are more likely to allocate resources more effectively than those who do not (Fischer, 2000). The use of 4D Planning also assists the planner in avoiding scheduling conflicts, analyse constraints and evaluate alternative construction methods (Vaugn, 1996) Research undertaken by Akinci (2000) demonstrated that 4D simulations could be used to highlight potential time-space conflicts on the construction site. This work aimed to detect conflicts in four dimensions, categorise the conflict according to

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taxonomy of time-space conflicts developed and prioritise the multiple types of conflicts between the same pair of conflicting activities. Work undertaken by Fischer (2001) demonstrated that 4D visualisations could provide a substantial cost benefit to the construction planning process. Presently various 4D visualisation software is commercially available. Packages such as Schedule Simulator (Bentley Systems Inc 2001), SmartPlant Review (Intergaraph, 2001), Project Navigator (VirtualStep Inc 2001) and FourDviz (Balfour Technologies, 2001) are available with costing varying according to the technology. In each of the cases either a CAD based system is used or alternatively Virtual Reality Modelling Language is used to present a real time model. Each of these systems provides the user to link the 3D product model to the schedule of construction tasks. However the linking of the product to process is manual and additionally plant and temporary works space objects could not be directly applied to the schedule and hence the 4D simulation (Heesom and Mahdjoubi, 2002b). Commercial software has been used to explore the application of 4D concepts carried out as a collaborative effort between CIFE and Walt Disney Imagineering (WDI) (Goldstein, 2001b). 4D simulations have also been used on large complex projects such as airport construction where they can provide crucial information to airport planning bodies, enabling the state of the airport to be visualised at a discrete point in a way that a 3D model of the final project could not (Edwards and Zeng, 1997). 2.4 Development Approach The research undertaken into the areas of Specialist trade visualisation demonstrated that no visualisation of specialist trade operations would be complete without the concurrent visualisation of the rest of the building product. Therefore a methodology was developed that allowed both the visualisation of Specialist trades in conjunction with the development of visualisation techniques for the whole building. Additionally it was also demonstrated that the undertaking of specialist trade operations required considerable plant and peripheral equipment in addition to the general labour resource i.e. manpower. For this reason an approach was developed to allow the inclusion of plant and other temporary works objects into the space analysis of the construction sequence. Geometry for the construction product is stored in the VIRCON database developed during Task 2 of the VIRCON Project The set up of the VIRCON database is assumed to be complete and the process of database set up is documented in Dawood et al. (2001). The key deliverables of the system would be: A tool to allow the planner to generate a plant library that could be used as a drag and drop tool to add plant and temporary works objects to the weekly construction layout.

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The development of a tool to allow the planner to add plant and temporary works objects to weekly plans. This would read information directly from the library and the VIRCON Database. The development of a tool to allow the planner to input paths required during the construction process. A tool to provide the ability to detect clashes and collisions between the building product and temporary works objects / plant objects during all stages of the construction process. A 3D / 4D visualisation tool to allow the planner to view the spatial layout of the site during any stage of the construction process. This tool will extend 4D visualisations by allowing the viewing of critical space analysis and space usage in addition to building product.

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3.0 SYSTEM DEVELOPMENT 3.1 Introduction In order to view the activities and the space usage in 4D, work was carried out to develop a simulator that has the capability to read the geometric information stored in the VIRCON database. This information is then used to generate 2D and 3D visualisations using the Virtual Reality Modelling Language (VRML). The simulation module is part of a suite of prototype products developed to enable visualisation and simulations of both product and spatial requirements. Each software prototype is developed as a stand-alone package and database information is accessed and written using Database Access Objects (DAO) 3.6. The input to each of the software tools emerges from the VIRCON database, and the Uniclass information associated with each task is then used to obtain geometric information relating to the building products. This information is then taken as input for the generation of the 4D VRML geometry. The basis of the simulations is looking on a work period of 1 week. Work undertaken by Kelsey et al. (2001) demonstrated that a 1 week planning period is a substantial level of detail and also that the micro planning of construction tasks within this period can be undertaken by the works supervisor. 4D VRML simulator produces weekly schedule information on the project plan. Structured Query Language (SQL) is used to query the VIRCON database to determine which tasks are being undertaken during each week of the project. Development of the software tools was undertaken using information from the Teesside University School of Health (SoH) Project. This information was used to populate the VIRCON database developed in Task 2 of the VIRCON Project and this formed the basis of software development as well as the beta testing of the software during the development stages.

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3.2 VIRCON Resource Manager (ResourceMan) 3.2.1 Overview This software prototype was developed to enable the planner to develop a reusable library of construction resources. This resource library would include both general resources and plant / temporary works resources. For each of the types stored in the library the corresponding space requirements are stored. 3.2.2 Software Rationale This software was developed to assist the planner in developing a library of resources that can be read into the construction scheduling process. It has been suggested that work area required can vary (Kelsey et al., 2001) however this figure could vary according to the operator type. This tool allows the planner to input the spatial requirements of operatives within their organisation who undertake a specific trade. Once generated, this library can be read into Microsoft Project and these general resources can be read into the resources section of the project and hence allocated to a specific task. In addition to the general resources ResourceMan also allows the planner to generate a library of supporting objects such as Plant and Temporary Works. These objects are required for many construction operations and can vary between both companies and projects. The extensible library allows the planner to create new objects, for example if a new type of plant is to be used. For each of the objects created in the library the spatial requirements are stored and these can be read by PlantMan to allow the inclusion of plant into the weekly spatial analysis. 3.2.3 Information Flow Figure 8 highlights the information flow through the ResourceMan tool. A library of both general and Plant / Temporary Works resources are stored along with their spatial attributes. Each library is extensible and stores unique names for all resources. The technology used allows the planner to generate more than one library and these can be stored in separate files allowing specific libraries to be generated for various project types. The output of the ResourceMan tool is a Microsoft Access 2000 database file that can be read as input by both Microsoft Project and PlantMan (discussed in Section 3.3)

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Figure 8: ResourceMan Information Flow 3.2.4 User Interface and User Interactions On Program start up the user is presented with the main interface as shown in Figure 9. This allows the planner to generate a new resource library or to open an existing library to amend resource objects.

Figure 9: ResourceMan start up Interface Once a new library has been generated the user can select to either amend the general resource library or the plant resource library. Selecting to edit the library will provide the planner with the library interface. The Graphical User Interface (GUI) for the Plant library can be seen in Figure 10.

Microsoft Project

PlantMan

ResourceStandards.mdb

Create /Open Resource Database

Assign attributes for General

Assign attributes for Plant / Temporary Works

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Figure 10: Resource attributes input dialogue

This allows the planner to update existing resources or add and delete resource objects currently stored in the library. Uniclass is also used to identify the resources used. The planner can select the generic description of the resource from the drop down list and from this description the associated Uniclass code is stored in the library and passed to the output documents. All of the descriptions in the Uniclass list are taken from Table M of the Uniclass Standards relating to Construction Aids. A built in function of the libraries ensures that no resource names can be duplicated thus ensuring that no confusion occurs when resources are being assigned to tasks or to the weekly spatial layout.

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3.3 VIRCON Plant and Temporary Resource Manager (PlantMan) 3.3.1 Overview The PlantMan prototype was developed to assist the planner in generating weekly spatial layouts of the construction site that include Plant and Temporary Works objects. The tool allows the interactive inclusion of plant and temporary works objects and route paths used by plant to be included in the space analysis and the 4D visual simulation. 3.3.2 Software Rationale The aim of PlantMan is the provision of the ability of the planner to include plant and temporary works objects into both the Critical Space Analysis process (North, 2001) and the visualisation process. Additionally the visualisation of route paths for plant objects is of vital importance and so this functionality is also included. Previous work in the area of site layout planning (Tommelein, 1994) has demonstrated that using drag and drop templates of objects representing material objects is beneficial in developing a site layout plan. This theory is used and extended further to provide drag and drop plant space objects. Temporary works and plant object require considerable space to operate on the construction site, and the space utilised during their operation is unable to be utilised by other activities. Currently planners ‘mark up’ plans to show areas that are unable to be used by activities manually however this tool aims to provide a semi automated approach to this mark up whilst extending this process into the digital genre therefore allowing more accurate and robust layouts. Once these weekly digital plans are generated, other tools within the VIRCON system can use them. The available space on the site in any given week can be viewed and this can be used to highlight areas that are available for various work packages. The information generated by PlantMan will also provide the basis for the 4D visualisation system discussed in Section 3.5 3.3.3 Information Flow Figure 11 highlights the information flow through the PlantMan system. Input information is taken from both the VIRCON database and the resource library generated by ResourceMan. Using the task and geometric product information stored in the VIRCON database, weekly plans are generated of the constructed facility. These 2D plans show both the work that has been completed to date and the work that is currently being undertaken in the week. This selection of process – product is undertaken by using the Uniclass information stored in the database. Information pertaining to plant objects and their spatial requirements are in put from the ResourceMan library. This loads the entire plant library from the selected file and stores these for use by the planner. The information flow layout through the PlantMan system can be seen in Figure 11.

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Figure 11: PlantMan Information Flow

VIRCON Database Resource Library

Weekly DXF

Plant Space Usage Reports

Plant Resources sent to VIRCON DB

Plant-Space Loaded Weekly Product Geometry

Query VIRCON Database for geometry of products being undertaken per week

Assign datum levels to Building Floors

Query VIRCON Database for geometry of products completed in each week

User relates product tables to building levels

Assign number of Building Floors

Select date to assign Plant / Temp Works objects

Select resource to add to site plan from resource library

Draw weekly layout plan using PlantMan interactive whiteboard

Drag and Drop Plant template onto weekly layout

Assign path / routes for plant for the week and assign plant templates from resource library to paths

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Once the 2D mark up plans have been generated and marked up by the planner to include all the plant objects and the paths required by various plant resources for a week this information is output for various uses. Four streams of output exist from PlantMan: Weekly DXF plans of the spatial layout of the construction site. The DXF files are stored in AutoCAD 2000 DXF format and show the information for each level of the constructed facility during each week of the project. These DXF files form the input for the developed AreaMan tool, a mark up tool to allow the creation of available workspaces for each week of the project. A Weekly space report of the construction site. This is a text file describing the amount of space used by plant and temporary works objects in a single week on each level of the constructed facility. Exporting of the plant / Resource information used to the VIRCON database. Resource information is stored in the Resources Table of the VIRCON database. All plant and temporary work information is extracted from PlantMan and included in the resource Table. This ensures that other developed simulators can use the plant resource information in visualisations Complete weekly geometric information. Entire geometry of the construction site for each week is extracted for use by the 4D simulator SpaceVis discussed in Section 3.5 This information includes building product, Plant Space and path geometric data. 3.3.4 User Interface and User Interactions On initialising the program the user selects the VIRCON database and the resource library that is to be used for the mark up operations. Once the VIRCON database is selected the number of levels (or floors) that exist with the building is taken from the Building table in the database. The user is then prompted to provide datum levels for each of the floors (this could be finished floor level). If this process has been done previously, the user is given the option to use the values previously entered or to enter new values for the level datum’s.

Figure 12: Level Datum Assignment Once this has been completed, the product tables in the VIRCON database need to be associated with the relevant levels or floors in the simulation. This can be done either automatically or manually. If the manual method is chosen, the user selects a building level from the drop down list and a list of products that exist on that level is presented. The user selects the products required and uses the

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‘Assign Tables’ button. If the Automatic approach is selected the user presses the ‘Continue’ button and all of the products associated with a particular level are associated. This process is undertaken by looking at the product table name and associating to a building. The product table names follow the convention: PR_01_00_Foundation = Product table for foundation in building ID 01 PR = Prefix for product table 01 = Building ID (i.e. 01, 02, ...., 99) 00 = Building Level (i.e. 00 = Groundwork, 0G = Ground Floor, 1F = First Floor,

2F = Second Floor, 0R = Roof, 0A = Atrium) Foundation = Generic Product Description

Figure 13: Product to Level Assigner

Once assigned the 2D geometry is generated for each week and each level of the construction project. The planner can then select a date to view the status of the project as shown in Figure 14.

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Figure 14: PlantMan Main User Interface

Once the weekly layout has been selected the planner can add plant and temporary works objects as required. The library is loaded into the drop down list and the dimensional attributes of the object are displayed. If required the user can update the geometry of the plant object individually. For example if a specific safety zone is required for the object, for example a hazard area around scaffold tower this can be added to the dimensions prior to the object being added to the layout. An example of adding plant objects to the layout can be seen in Figure 15.

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Figure 15: Drag and Drop Plant Objects from the Resource Library

Other attributes that can be amended during the positioning of plant objects include the rotation of the object. This can be set to 0 or 90 degrees as all objects are deemed to be rectangular. A further option allows the planner to add the object for more than the week selected during the mark up process. It is often the case that plant or temporary works will exist for more than one week in a particular place and so the ability is present to assign the object for numerous weeks. Once added the object will appear in the same position for the weeks stipulated.

Figure 16: Assigning Dynamic Movement Paths for Plant Objects

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Once all plant objects have been added for a particular week dynamic route paths can be assigned. Using the Interactive Path Assigner the planner can drag a route path onto the weekly layout and can attach a plant object stored in the library to the path. An example of assigning a path to the weekly layout can be seen in Figure 16. Following all of the assigning of Plant Objects and route paths a space report can be generated. Spatial information is stored in a text file presenting information on the total space occupied by the building product and space occupied by the plant objects for each week of the project.

Figure 17: Extract from Plant Space Usage Report

Finally once all plant objects have been added to the weekly plans a set of plans are exported in DXF format for use with the AreaMan mark up tool. An example of an exported DXF file is shown in Figure18.

Figure 18: DXF Site Layout Generation Routine

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3.4 VIRCON Temporary Works Clash Identifier (ClashMan) 3.4.1 Overview The Temporary Works Clash Identifier (ClashMan) was developed to assist the planner in detecting collisions that exist on a weekly basis between plant and temporary works objects positioned using the PlantMan tool and completed products in the building. ClashMan allows the planner to test for collisions between these 2 sets of objects in 3 dimensions using a developed collision detection algorithm. The collisions can be detected for a particular week of the project or once all plant objects have been assigned collision detection can be undertaken for the entire project on all levels of the constructed facility. 3.4.2 Software Rationale The aim of ClashMan is the ability to detect collisions and conflicts in both 3 and 4 dimensions. Once detected these collisions can be viewed in the 4D visualisation tool discussed in Section 3.5 During the positioning of objects and paths in PlantMan, there exists the opportunity for collisions to occur between the constructed product and the object placed. ClashMan makes use of a derived algorithm based on the raw collision detection theory (Sinjur, 2001). This algorithm checks each vertex of the plant space objects to identify if any collisions are taking place with construction products. Some previous work has used algorithms to identify collisions that exist between static workspaces (Akinci, 2000) however this prototype extends this theory to include the detection of collisions between product and dynamic plant workspaces. 3.4.3 Information Flow Figure 19 demonstrates the information flow through the ClashMan system. Input is taken from the VIRCON database and from the weekly geometry output of the PlantMan system. This includes the geometry of both completed building products and the plant / temporary works objects placed. The user selects the VIRCON database from its stored location. Once the input information is selected the user can select to perform collision detection on a selected week and a selected level or perform collision detection for all weeks on all levels of the building being constructed. If a collision is detected the geometric information is written to a database file and stored in readiness for use by the 4D simulation software.

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Figure 19: ClashMan Information Flow The detected information, once stored, can be used to output the collision information using two methods. A text-based report can be generated that provides a list of the collisions that occur with each week of the project The geometry stored can be used to generate Virtual Reality objects allowing the planner to visualise the location of each of the collisions that exist in the site layout.

VIRCON Database PlantMan Geometry Information

Check Vertex collisions between Plant Space Objects and Building Products

Select Level and Date for collision detection

Write geometric data of any colliding objects found to DB

Automated detection of collisions for all weeks and all building levels

Geometric Properties of colliding objects for use with ProSpaceVis

Text report of the number of collisions detected per week per building level

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3.4.4 User Interface and User Interactions On initialising ClashMan the user is presented with the main ClashMan interface shown in Figure 20. The Planner can then open the VIRCON database from its origin and this will provide the project Start and End dates in the information panels shown at the bottom of the interface. The level (or floor) information for the building is derived from the Building table of the VIRCON database. Once loaded the planner can select to perform collision detection for specific dates or for the entire project using the radio buttons. If a specific week is to be tested the planner can choose a date from the calendar and select a level of the building to check by selecting from the drop down menu.

Figure 20: ClashMan User Interface

Once detected the collision information can be written to a collision report file which lists all collisions occurring within the project on a weekly and level basis. An example of a collision report output file can be seen in Figure 21

Figure 21: Example of collision detection Report

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3.5 VIRCON 4D Virtual Reality Project and Space Simulator (SpaceVis) 3.5.1 Overview SpaceVis is a prototype 4D visualisation software system, developed to allow the user to visualise the status of the project at any stage of the construction process. Additionally, the tool allows an intelligent and interactive 3D and 4D visualisation of space usage throughout the duration of the construction period. 3.5.2 Software Rationale The aim of SpaceVis is to provide a visual output to the information generated by the VIRCON database, PlantMan, AreaMan and SpaceMan. The tool will allow the visualisation over time of the constructed product and the spatial loading of the construction site. Additionally the tool allows the visualisation of dynamic route paths followed by plant objects as created by the PlantMan tool. Many previous 4D prototype systems have utilised the Virtual Reality Modelling Language (VRML) to generate the 3D objects. It is also the case that some commercially available software with the ability to present 4D simulations is using VRML. SpaceVis makes use of VRML to generate both building product objects and also space objects (both plant objects and static work areas). Due to the nature of VRML objects can also be made intelligent. This use of intelligent objects is exploited in SpaceVis to enable the planner to interact with the visualisation. The user is able to request information from objects in the visualisation. Dynamic objects can also be used and visualised in VRML. This enables the viewing of objects following paths as generated using the PlantMan Interactive Path Assigner. The ultimate purpose of the software is to provide a Real Time interactive simulation of the construction process whereby the planner can move to any location and view the progress and space usage from any viewpoint. 3.5.3 Information Flow Figure 22 highlights the information flow through the SpaceVis system. Input information into the simulator is derived from geometric and temporal information stored in the VIRCON database and from the geometry created from PlantMan. All of the geometry generated in VRML is based on a weekly take off of activities and space. The 4D VRML simulator is platform and software independent however in order to view the 3D VRML objects a VRML plug in is required. These plug-ins such as Cortona VRML Client and Cosmo Player are free to download from the World Wide Web. The SpaceVis tool has been developed using Visual Basic Programming Language and utilises class tools developed by EM7 to allow the dynamic generation of VRML code from user input. Once the geometric information is read into the SpaceVis tool, VRML objects are generated to depict the status of the project in each week. The process required in order to generate the VRML components can be seen in detail in Figure 23.

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Figure 22: SpaceVis Information flow

VIRCON Database Geometry Exported from PlantMan

Weekly VRML Files

Space Object attribute Files

Generate VRML Files for building product and space objects

Assign datum levels to Building Floors

Generate associated attributes files for VRML space objects

Assign number of Building Floors

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Link VRML objects with attribute files to create intelligent objects

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Figure 23: VRML Generation Process

Determine Start and End date of the week.

Create an empty shell of the weekly VRML file.

Query produces geometry

Get Geometric information for each object.

Generate shape and geometry using the resulting coordinates.

Add the shape to the main VRML grouping node.

Add the main VRML grouping node to the Weekly VRML file.

Calculated new Start and end dates for the next week.

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Add the space template objects to the Weekly VRML file

Query the database for Building Product geometry of objects under construction in Week

Generate space objects using information from AreaMan and SpaceMan

Query to determine if Plant objects exist in

Week

Query to determine if AreaMan spaces exist

in week

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During the process of VRML generation, attribute files are created to store specific information about the Plant Space objects that are located on the site in any week. These attribute files are linked to the objects by using the Anchor node in VRML and clicking on a space object will open the attribute file to allow the planner to view its information. Geometric information relating to the spaces generated by AreaMan and SpaceMan is also directly read from the VIRCN database. The Spatial overload of each of the generated spaces is converted into a colour sequence so the any overloads of workspaces can be easily identified. The output of the tool is an interactive 4D real time simulation of the construction sequence that will allow the user to view and query the spatial load of the construction site during any given week. 3.5.4 User Interface and User Interactions On initialising the program, the user is presented with the option to load the VIRCON database. Once loaded this stores all of the information pertaining to the project into the SpaceVis program, for example the number of levels in the building, the datum levels for each of the floors, the start date and the end date of the project. The building levels are used to determine the height of the available workspaces generated by AreaMan and SpaceMan (North, 2001). The next stage of SpaceVis is the generation of the VRML files. For each week in the project a virtual reality environment is generated ad these are linked together in order to view the 4D simulation. Prior to the generation of the VRML files, the ability is presented for the planner to create an animated flight path around the project. Navigation of a virtual reality environment can be delicate and so the ability to draw a predetermined path in 2D will assist the planner in ensuring that all required detail is seen. If the planner wishes to generate an animated path, whiteboard is presented with a 2D plan of the construction site drawn. The planner can simply click the locations of the points he would like to visit. The dialogue boxes for the animated path creation can be seen in Figure 24.

Figure 24: Animated path generation

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Once all of the VRML objects have been generated, the user can view the simulation by opening the 4D VR simulation window. This window enables viewing, navigation and interaction with the virtual construction site. Various options are presented to the planner, through the radio buttons on the interface. The user can view the building, the collisions that were detected by ClashMan, the plant space usage generated by PlantMan (this also includes the dynamic objects representing the object moving on specified route paths) and the static spaces generated by SpaceMan. These static workspaces are generated with varying colours to depict the percentage overload of the space. The percentage overloads are categorised in bands of 20% and the redder the space object the higher the overload.

Figure 25: Selection of monitoring date for 4D Simulation

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Figure 26: 4D VRML view of construction products

Figure 27: 4D VRML View of Plant Spaces assigned using PlantMan

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Figure 28: Plant Space attributes shown in 4D information window

Once a monitoring date has been selected, the date can be increased or decreased by 1 week by using the ‘video style’ buttons on the control panel (See Figure 30). Additionally the double arrow buttons run the simulation automatically by increasing or decreasing the week on a preset time so that the simulation can be viewed automatically on a week-by-week basis.

Figure 29: 4D Simulation Control Panel

A final feature of SpaceVis is the ability to open the Microsoft Project file from within the software application (See Figure 31). This facility enables the viewing of the project schedule whilst the simulation is being undertaken presenting a comprehensive view of the construction process.

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Figure 30: Microsoft Project viewing Window

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4.0 INTEGRATION WITH VIRCON SOFTWARE 4.1 Overview Each of the tools described above form a section of the VIRCON software suite. Each of the prototypes developed require the VIRCON database to operate. Additionally the input and output of each of the prototypes developed forms input to another software prototype developed for example AreaMan. Therefore the integration of the developed tools with both each other and with other VIRCON tools is of vital importance. 4.2 Software Integration The four tools developed integrate with each other through the reading of database information. In addition to each of the tools reading information directly from the VIRCON database, subsidiary information is passed between the applications using Microsoft Access 2000 database formats.

Figure 31: Software integration The seamless integration of each of these tools is vital to ensure that information is also passed correctly to other applications in the VIRCON software suite. Additionally errors in the distribution of information between PlantMan and the 4D simulator could result in errors occurring in the simulation, leading to false results. Additional temporary databases are generated in the directory where applications are stored. Using this storage method ensures that information is not lost in directories that are specific to certain computers. Additionally VRML files generated by SpaceVis are stored in the program directory of the 4D visualisation module ensuring all files can be located during the simulation process.

ResourceMan PlantMan ClashMan

SpaceVis

Libraries stored as Microsoft Access 2000 database

Access database read as inputusing Data Access Objects (DAO) 3.6

Geometry stored as database information (MS Access 2000)

Access database read as input using Data Access Objects (DAO) 3.6

Geometry stored as database information (MS Access 2000). Read using DAO 3.6

Geometry stored as database information (MS Access 2000). Read using DAO 3.6

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4.3 VIRCON System Integration In order for the software to work effectively, seamless integration is required between the other tools in the VIRCON software suite. Information flow is critical between the various prototype systems and each of the software packages described in this report interacts with other VIRCON prototypes and proprietary software both directly and indirectly. Figure 33 highlights the interactions that take place between ResourceMan and PlantMan and other systems. ResourceMan generates a library of resources that is saved as a Microsoft Access 2000 file. This file is read by Microsoft Project and forms the resource library in MS Project. The data stored in the library is also read by PlantMan as discussed in Section 4.2. PlantMan reads geometric information in the form of a Microsoft access 2000 file directly from the VIRCON database. This is achieved by the use of Data Access Object 3.6. During the generation of weekly site layout plans in dxf format, PlantMan makes use of the AutoDesk AutoCAD object model. The generation of the dxf files is undertaken by using AutoCAD 2000 as a medium and the dxf files are stored in release 2000 format. During testing this transfer from PlantMan to AreaMan has resulted in no data loss by AreaMan.

Figure 32: VIRCON System information flow (Winch et al., 2002)

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Figure 34 demonstrates the integration of SpaceVis with the VIRCON database and other aspects of the VIRCON Software during the analysis phase. Spaces analysed by SpaceMan are uploaded into the VIRCON database and these are read by SpaceVis and displayed in the 4D simulation. The geometry and analysis information produced by SpaceMan is queried by SpaceVis using Structure Query Language (SQL) and read into the simulation engine using DAO 3.6

Figure 33: VIRCON Analysis configuration

(Winch et al., 2002)

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5.0 CONCLUSIONS 5.1 Overview This research Task has produced 4 prototypes software applications that are used to generate a more robust spatial analysis of the construction site. The prototype systems build on previous research in the field by: Allowing the generation of a generic library of plant and resource objects along with their spatial requirements Allowing a more robust spatial analysis of the construction site in 4D by enabling the inclusion of Plant objects in the 4D simulation. These plant objects are read by AreaMan as occupied spaces and cannot therefore by misconstrued with space available for work to be executed. Providing the ability to view dynamic path routes in 4D dimensions. Previous 4D simulations have presented the construction site in a static nature and have not demonstrated how moving objects such as plant can affect workspaces. Generating an interactive 4D simulation. The SpaceVis tool generates intelligent space objects that will present the user with information about them on request. Providing the ability to detect potential conflicts in 3 dimensions between temporary works objects and plant and constructed products that make up the building. Providing a visual output for critical space analysis. Within the 4D simulation occupied spaces can be viewed and their percentage capacity can be seen in a visual context that can be related to the construction site as a whole. 5.2 Limitations Each of the tools developed has limitations both in their programming and the final output. The following section presents a review of the known limitations of each of the developed prototypes. 5.2.1 ResrouceMan Entries into the Resource Library have to be input manually by the user. Each resource has to be included and there is no provision for plant objects to be copied between libraries. All resource spaces for plant are rectangular in shape. Each of the plant resources included has length, width and height dimensions. Very often it is the case that plant resources (for example a crane) are not rectangular. These objects have to be simplified in order to be input into the library.

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5.2.2 PlantMan As with the ResourceMan library, PlantMan can only assign rectangular objects to the site layout. This limitation is inherent of the limitations of ResourceMan. The drag and drop is limited to 2D plans generated by PlantMan. Each of the objects can only be placed in 2 dimensions on the floor layout. Therefore no account can be made of potential space that may be available underneath or above a plant objects. The weekly layout plans show all objects that are related to a specific task. For example if the task is construct inner leaf walls, the layout plan displays the entire array of inner leaf walls for that week. In reality during the first week of the activity half of the walls may be erected whilst no work is carried out on the other half. On the plans this information is not displayed and it appears as though all walls are being worked on for both weeks. At present the ability to add dynamic paths to the weekly layout is limited to two points. Obviously route paths are more complex than this and could include objects moving around objects requiring building products. The frequency of the objects moving along the path is constant for all objects thus meaning that the paths observed in the 4D simulation are generic and can be used for visualisation purposes only. For example the time interval (frequency) of paths could be different for an excavator constantly working than for an access path required for trucks. 5.2.3 ClashMan Currently ClashMan detects conflicts only between products that are in place and temporary works / plan objects. No account is taken of objects that are currently under construction. ClashMan only reports the number of conflicts detected in any given week and does not provide a categorisation of the conflicts for the planner. By categorising the type of conflict the planner could resolve the most serious first. The Collision detection algorithm used by ClashMan uses the raw method of clash detection. This method tests each vertex of two objects to identify if a collision exists between the objects. This method is relatively slow and requires more processing power than other techniques such as the Space Subdivision Method (Sinjur, 2001). 5.2.4 SpaceVis The visualisation of objects is constrained to simple rectangular boxes and the geometry of products stored in the database are depicted by their bounding box. Objects in SpaceVis simulation are recognised and identified by colour only. No textures are used to present a more photo-realistic simulation. The frequency of path objects is also a constraint on the simulation developed by SpaceVis. This is inherent of how the paths are generated in PlantMan.

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5.3 Recommendations for future development In order to improve the functionality of the prototype systems the following recommendations are made for future developments: The improvement of the drag and drop objects. These could be made available in a 3D format and so allow exact positioning of the object on the site layout. These drag and drop objects could be made available in the Virtual Reality environment thus enabling the planner to add and record the objects directly into the 4D simulation. Further to the above point as the introduction of Industry Foundation Classes and web technologies the possibility exists for plant objects to be stores in a Web environment. This would mean that remote libraries could be established containing plant and temporary works objects. These objects could possibly be available direct from manufacturers and could be dragged in 3D into the 4D simulation. The 4D Virtual Reality simulations could be greatly enhanced through the use of photo realistic textures. The use of these textures, both on the constructed produce objects and on the plant / temporary works libraries would increase the realism. The creation of high-end graphic displays and a fully immersive PlantMan system. The PlantMan prototype could be further developed to enable a 3D interactive environment whereby the user could stand inside the site boundary and place objects from the library using haptic devices. The geometry stored in the database to represent the building products could be increased thus allowing a more realistic depiction of the simulation. Further development of PlantMan, ClashMan and SpaceVis to allow the level of detail of the 4D simulation to be varied according to the user. At present the simulation can be viewed on a weekly basis, however for some operations this time scale cold be to much and so some detail could be overlooked. The ability to select the level of the temporal dimension would increase the ability of the 4D visualisation to be used by any construction project.

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6.0 REFERENCES Aalami, F. (1998). Using Method Models to Generate 4D Production Models. Ph.D. Thesis, Civil Engineering. Stanford University. Akinci, B., Fischer, M., Levitt, R. and Carlson, R. (2000) Formalisation and Automation of Time-Space Conflict analysis. Working Paper #59. CIFE, Stanford. Akinci, B., Fischer, M., Levitt, R. and Carlson, R. (2000) Automated Generation of Work Spaces Required by Construction Activities. Working Paper #58. CIFE, Stanford. Barrett, P. (2000) Construction Management pull for 4D CAD. Construction Congress VI, ASCE, Orlando, Florida, February 2000. Eds Walsh, K.D. pp. 977-983 Dawood et al. (2001) VIRCON Project: Data Capture and Database Development. University of Teesside, 2001 Dawood, N., Hobbs, B., Akinsola, A., Mallasi, Z., Mahdjoubi, L., Heesom, D., Winch, G., Penn, A., Kelsey, J., Edkins, A. and North. S. (2000) The Virtual Construction Site: A Decision Support System for Construction Planning (VIRCON). Conference on Construction Applications of virtual Reality: Current Initiatives and future challenges. Teesside, UK. Edwards, R. and Zeng, B. (1997) A Case Study: 4D modelling and simulation for the modernisation of Logan International Airport. Conference on Airport modelling and simulation, ASCE. Eds Mumayiz, S.A. and Schonfield, P. Arligton, Virginia. pp 8-27 Fischer, M. (2000) Benefits of 4D models for Facility Owners and AEC Service Providers. Construction Congress VI, ASCE, Orlando, Florida, February 2000. Eds Walsh, K.D. pp. 990-995 Fischer, M. (2001) Frontiers of Virtual Building. Workshop on Virtual Construction. The European Network of Construction Companies for Research and Development (ENCORD). Essesn, Germany. 26-27 November 2001 Goldstein, H. (2001a) 4D: Science Fiction or Virtual Reality? Construction.com Features, April 16, 2001. <http://construction.com/NewsCenter/it/features/01-20010416.jsp> (accessed 20 April 2001) Goldstein, H. (2001b) 4D: Maestros of Design and Construction Render a Virtual Masterpiece Construction.com Features, May 2, 2001. <http://construction.com/NewsCenter/it/features/01-20010502.jsp> (accessed 6 May 2001) Heesom, D. and Mahdjoubi, L. (2002a) Technology Opportunities and Potential for the Virtual Construction Site: Emerging Research Initiatives. School of Engineering and the Built Environment, University of Wolverhampton. ISBN: 1-86162-001-2

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Heesom, D. and Mahdjoubi, L. (2002b) Technology Opportunities and Potential for the Virtual Construction Site: Existing Technology and Potential. School of Engineering and the Built Environment, University of Wolverhampton. ISBN: 1-86162-003-9 Jenkins, B. L. (1998) Virtual Manufacturing: The new frontier. Computer Graphics World, March 1998, pp23-24 Kelsey, J., Winch, G. and Penn, A. (2001) Understanding the Project Planning Process: Requirements Capture for the Virtual Construction Site. Bartlett Research, Paper No. 15. University College London, UK. Koo, B., Hung, W., Long, S. and Wiederhold R. (1998) Using 4D CAD to Evaluate the Executability of a Construction Schedule. Mcwhinney Project, June 1998 <http://www.stanford.edu/~bonsang/4Dslide/bonsang-main3.htm> (accessed 10 July 2001) Korves, B., Duffill, A. W. and Williams, G. W. (1996) Virtual Manufacturing; The implementation of virtual reality in the manufacturing environment. Second annual symposium of postgraduate research. University of Birmingham, April 1996. pp 9-13 McKinney, K., and Fischer, M. (1998) Generating, evaluating and visualizing construction schedules with 4D-CAD tools. Automation in Construction, 7(6), pp433-447. McKinney, K., Kim, J., Fischer, M. and Howard, C. (1996) Interactive 4D CAD. Proc. Of the Third Congress in Computing in Civil Engineering, ASCE, Anaheim, CA, pp 383-389. North, S. (2001) SpaceMan: developing a critical space analysis prototype. Task 5: VIRCON Technical Report, University College London, 2001. Retik, A. (1995) VR system prototype for visual simulation of the construction process. EPSRC conference, Salford, United Kingdom. pp90-93 Retik, A. (2000) VR-based planning of construction site activities. Automation in construction, Vol. 8 pp 671 – 680. Riley, D. (2000) The Role of Four-Dimensional (4D) Modeling in Trade Sequencing and Production Planning. Construction Congress VI, ASCE, Orlando, Florida, February 2000. Eds Walsh, K.D. pp. 1029-1034 Riley, D., (1998). 4D Modeling Specifications for Construction Work Spaces. Proceedings 5th ASCE Congress on Computing in Civil Engineering, 1998, Boston, MA. Sinjur, S. (2001) Collision Detection between moving objects using uniform space subdivision.

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Tommelein, I. D. (2000) Impact of Variability and Uncertainty on Product and Process Development. Construction Congress VI, ASCE, Orlando, Florida, February 2000. Eds Walsh, K.D. pp. 969-976 Vaugn, F. (1996) 3D and 4D CAD Modeling on Commercial Design-Build Projects. Computing in Civil engineering Congress 3. Anaheim, California. June 1996. Eds Vanegas, J and Chinowsky, P. pp 390-396 Winch et al. (2002) VIRCON Conceptual diagrams. Output from VIRCON Technical Meeting. January, 2002. World Wide Web Reference <http://www.infinity-technologies.com> Accessed 20 December 2000 World Wide Web Reference <http://www.virtualstep.com> Accessed 20 December 2000 World Wide Web Reference: <http://www.bentley.com> Accessed 20 December 2000 World Wide Web Reference: <http://www.intergraph.com/visualization> Accessed 20 February 2001

School of Engineering and the Built Environment University of Wolverhampton ISBN: 1-86162-004-7