proposed approach

the solution.the solution.

Localization technologies:• Off-board track1

• Dead reckoning• Optical imaging

Obstacle detection technologies:• Ultrasonic2

• Infrared3

• Laser

User interface technologies:• LCD4

• Keypad5

Motor control technologies:• Custom DAC• Standard DAC

Microcontroller technologies:• Axiom CMD-5656

• Handyboard Denotes selected technology

• Single-level floorplan• Typical hallway environments• Obstacle detection in forward direction• Single, predefined destination

assumptions limitations

design objectives

• Primary: hospital staff• Secondary: cognitively disabled

wheelchair passenger

Prototype design & implementation:• User-selectable starting points and

destinations• Track-guided navigation using

photodetectors• Microprocessor-controlled operation

and interfacing using LabVIEW• Obstacle and drop-off detection

• Indoor setting with typical hospital floor type such as tile, hardwood or short carpet• Single-level floorplan, not designed for elevator transport

Dr. Nicola Elia

unassisted transportation for the cognitively disabled.unassisted transportation for the cognitively disabled.

Many people live with cognitive disabilities that cause them to be confined to a wheelchair and to depend on someone else for movement. Especially in hospital environments, these persons need to move frequently between exam rooms and departments. In the absence of family or friends, the assistance required adds a burden to the already hectic schedules of the hospital staff. The system proposed for this project is a wheelchair that has the ability to navigate autonomously through a hospital while detecting obstacles and stairs. Using a microprocessor programmed with LabVIEW Embedded 8.2, the wheelchair will obtain the user’s desired route and travel to the destination autonomously.

Background:• Hospital patients often need to relocate

between departments and exam rooms• Patients confined to wheelchairs

present extra burden on hospital staff

Task:• Develop an autonomously-controlled

wheelchair with obstacle detection

abstract

what is the purpose?what is the purpose? problem statement

who can use it?who can use it? intended users

where can it be used?where can it be used? operating environment

what are the constraints?what are the constraints?

what are the requirements?what are the requirements?

• Simple user interface• All-in-one design with minimal

alternations to operating environment• Safe for passenger and bystanders

The design executed in this project requires the implementation of several complex technologies including motor control, sonar and photodetector arrays, a navigation system, embedded programming, and user interfacing. The resultant prototype will highlight the key considerations for autonomous wheelchair navigation.

the design.the design. technology and testing considerations

the summary.the summary. closing material

• Indianola Home Medical – donation of replacement motor control box and joystick• National Instruments – technical support for LabVIEW Embedded 8.2

who has provided assistance?who has provided assistance? acknowledgements

what are the deliverables?what are the deliverables? expected end-product

Brennen Beavers - CprE Margaret Shangle - EE John Volkens - CprEVee Shinatrakool - CprE Tara Spoden - EE Brian Yauk - EE

National Instruments (Austin, TX)Andrew Dove

the timetable.the timetable. project schedule and measurable milestones

the resources.the resources. estimated resources

134

276237

284256 266

0

100

200

300

Hou

rs

Brennen Vee Margaret Tara John Brian

proposed solution

intended uses

• Patient transport between hospital departments and exam rooms

• Demonstration of LabVIEW Embedded

functional requirements

• User-selectable destinations• LabVIEW controlled operation• Obstacle and drop-off detection• Path calculation and recognition

• Motorized wheelchair provided• Unobstructed wheelchair mobility• Uninhibited passenger accommodation• Controlled by LabVIEW Embedded 8.2

• Conceptual prototype, not designed for commercial reproduction

• LabVIEW Embedded-controlled autonomous operation

• Track-guided navigation• Obstacle and drop-off detection

Other deliverables:• Project Plan• Design Report• Final Report• Poster• IRP Presentation

• Familiarize with wheelchair motor control and LabVIEW development

• Research compatible technologies• Purchase or custom-build components• Test and evaluate component

functionalities• Modularly design and test software

functions• Implement and test full system

prototype

Item Description: Cost

Sensors $477

Interface hardware $135

Poster $25

Labor at $10.50/hr:  

Brennen Beavers $1,407

Vee Shinatrakool $2,898

Margaret Shangle $2,489

Tara Spoden $2,982

John Volkens $2,688

Brian Yauk $2,793

Total: $15,894

* Microcontroller and LabVIEW provided by National Instruments** Wheelchair provided by Senior Design

Photodetectors - $225Sonar Sensors - $125Compass - $52IR Sensor - $15LCD - $35Keypad - $25Poster - $25Interface Hardware - $135

Figure 4. Financial requirements (excluding labor)

• Sonar imaging• RFID• GPS

• Imaging• Mechanical

Testing considerations:• Functionality testing• Modular subsystem testing• Full system testing in controlled environment by:

• Team members (alpha testing)• Outside volunteers (beta testing)• Advisor• Client

• Touchscreen• Audio

Figure 2. Simplified full system interface

DAC

DAC

24V Battery

12Vreg

JOYSTICKCONTROLLER

MOTOR CONTROL

BOXPHOTODECTOR

ARRAYS

COMPASS

IR SENSOR

LCDDISPLAY

KEYPAD

SONAR ARRAY

5Vreg

Control Output

User Interface

Processing

Sensors

ADC[0:14]

ADC

ADC[0:4]

ADCUSB USB

[0:7]

[0:7]

DB15

• Mini-ITX

Figure 3. Simplified program flow

NOTIFY USER

No

Yes

Yes

No

NoYes

No

Yes

No

Yes

No

No

CHANGE SPEEDOR DIRECTION

IDLE

START

KEYPRESSED?

GET INPUT &CALCULATE

PATH

SCANENVIROMENT

CRITICALOBJECT?

STOP CHAIR &SOUND ALERT

CHECKTRACK

SENSORS

INTERSECTIONDETECTED?

TURNNEEDED?

MOVE FORWARD

DESTINATIONREACHED?

CHAIRON TRACK?

1

3

5

2

4

6

Figure 5. Personnel requirements

student membersstudent members clientclient faculty advisorfaculty advisor

Figure 1. Component mounting diagram

1. LCD & keypad2. Microcontroller3. Modified joystick4. Motor control box

5. Batteries6. Photodetector arrays7. Sonar array8. IR sensor

1

2

4

5

3

6a

6b

8

7