toolbars and attributedata input forms. Aparent map was created in ArcGIS and all necessaryelements including asset layers,symbology, background mappingetc. were output to the Leica Zeno15 GIS data collector by means ofthe ESRI AXF format.

Workflow chainThe collected data consisted of geospatial and attribute data relating to assets. The data wastransferred using the ESRI AXF format via the Leica Zeno DockingStation. Once collected, the datawas checked into ESRI ArcMap for storage, display and analysis.

Accuracy EvaluationA separate geospatial accuracyevaluation was carried out basedon accuracy achieved using both

The project was to create asystem for the collection andstorage of asset inventory databased upon ESRI ArcGIS andthe Leica Zeno 15 GIS handheld,and evaluate with respect toease of use and geospatialaccuracy.

The completion of an MSc inGeospatial and Mapping Sciencesat the University of Glasgow wasthe main driving force behind thisproject. It seemed sensible to baseit on the creation and evaluationof a system which could be bene-ficial to Estates Technical SurveyorColin Bradford’s employer NorthAyrshire Council.After investigation into existingdata standards and user requirements, Leica Zeno Fielddata capure software customisationwas carried out with respect to

CompanyNorth Ayrshire Council

ChallengeCreate a pilot project for the creationof a GIS based asset inventory including road infrastructure

ObjectiveA system providing asset location to OSNational Grid coordinates by collectingall required data including attributes inreal-time without post processing

Project period2010-2011

LocationIrvine, Scotland

DeliverableGIS based asset inventory representingall required road assets in the form ofgeo location and related attribute data,e.g. lighting columns, gullies, manholes,traffic signals and road signs.

Hardware and Software� Surveying hardware and software- Leica Zeno 15 GIS Data Collector- Leica Zeno Field Onboard Software- Leica SmartNet Reference Station

Network

� Office software- ESRI ArcGIS- ESRI ArcPad Studio- ESRI Arcpad Toolbar Manager

Leica Geosystems TruStoryLeica Zeno 15 for Asset Inventory

Leica SmartNet and SBAS (EGNOS)RTK systems. This was based upontwo main criteria. These were asfollows:

Accuracy relative to OrdnanceSurvey Mastermap TopographyLayer achieved using SBAS andLeica SmartNet via OSTN02 trans-formation. This involved collectingdata with the Leica Zeno 15 GIShandheld using normal workingmethods, i.e. holding the deviceabove a feature. A large sample ofwell defined OS map features wereselected and positions were measured using the Leica ZenoField Software to collect GPSobservations. Horizontal displacementerror from the relative map pointswas recorded and the abbreviatedresults were as follows:

(GNSS: GPS only; Conditions: open sky)

This evaluation may also indicateother factors relating to errors inthe OS mappimg in addition to theevaluation of the Zeno GNSS performance.

Absolute accuracy achievedusing SBAS and Leica SmartNet.The basis for this evaluation wasten defined control points established using dual frequency,post processed static GPS. Thesepoints were then each measuredtwice using the Leica Zeno 15 /Zeno Field with a fixed antenna/tripod assembly using both SBASand Leica SmartNet RTK. Thisresulted in a sample size of twentyfor both RTK methods. Colin’sevaluation of the absolute accura-cy achieved using Leica Zeno withboth RTK methods was as follows:

(GNSS: GPS only; Conditions: open sky)

Benefits- Leica Zeno 15 GIS Data Collector pro

vides a user friendly interface, and enables standardised data collection through customisation and procedures

- Use of Zeno Field software enables theoperator to take all required ESRI ArcMapelements into the field for editing

- Use of the GNSS antenna enables theaccurate geo location of assets to a standard which more than meets the needs of a GIS regardless of RTK correction method

- Location can be obtained from Leica DISTO measurements relative to background map features, should satellites be hidden

After the accuracy evaluation, ColinBradford came to the conclusionthat Leica SmartNet providedaccuracy which was more than sufficient for the representation ofthe data. Should SmartNet beunavailable due to GSM/GPRS signalloss, then SBAS would provide asatisfactory backup.

ConclusionThe creation of an accurate inventoryenabled effective asset manage-ment. A pre requisite to efficientmanagement was accurate, reliabledata relating to all relevant assetswhich enabled better planning andresource management based on datarelating to condition, asset type,location etc. GIS provides the perfect platform upon which tostore this data.

The Leica Zeno 15 provides a userfriendly interface, and enables standardised data collection throughefficient customisation and procedures.The use of Zeno Field softwareenables the operator to take allrequired ESRI ArcMap elements intothe field for maximum efficiency.

Leica Geosystems AGHeinrich-Wild-Strasse CH-9435 Heerbrugg Switzerland Phone +41 71 727 31 31

www.leica-geosystems.com

RTK correction

system

Mean hori-

zontal distance

error (m)

RMSE of

horizontal

distance

errors (m)

SBAS (EGNOS) 0.98 1.01

Leica SmartNet 0.48 0.54

RTK correction

system

Mean hori-

zontal distance

error (m)

RMSE of

horizontal

distance

errors (m)

SBAS (EGNOS) 0.77 0.81

Leica SmartNet 0.20 0.22