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
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0
100
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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