WheelChair/Howard Community College/fall2012/p3-503-SMVS

Problem Statement

Fix and re-assemble the individual components of the wheelchair, thereby allowing us to gain control of the wheelchair's drive functions, which opens up the possibility of controlling the wheelchair through a computer connection or an Arduino. Reverse engineer to find out why the right motor does not work. Bend brake handle back into place.

Team Members

Cale
Broemmelsiek
Onzere
Smith

Summary

For the first portion of this project, we recreated what the previous team did and made a tutorial on how to charge the wheel chair batteries. We moved on to documenting the orientation of the wires on the wheelchair and how the motor controller works and made a diagram of it. Then, we fixed the right motor and tested both motors by timing there rotation insuring the wheel chair would go strait. We then documented the connection between the joystick and the motor controller. For this project's next steps we recommend concentrating on making a working joystick or a replacement of the joystick- motor controller combination.

Poster

Story

11/15/12

We split the group into 3 groups to work on each part of the wheelchair independently.

1. Victor: Wheelchair motor

2. Steven Cale: Battery charging and joystick control

3. Marc: motor control

4. Stephanie: Supervisor,troubleshooter, photo documentation and design

11/20/12

We charged the battery correctly and wrote a tutorial on how to charge it safely using the Thunder AC6 charger | shown here]. We found someone who has a wheelchair being controlled with a logic controller and we plan on recreating what he has done shown here. We also found and documented the electronic controller that the joystick uses to signal the motor and controls. The controller is called a MKIV Quad Pulse(see link below) [| MKVI Quad pulse documention]

This is the picture that the manual provides for the MKIV Quad Pulse controller, you can see the three inputs that match up with the actual pictures

These are the various inputs that the electronic controller receives from the joystick controller

11/29/12

We have diagrammed and documented all the connections that we need to make on the wheelchair [| shown here]. The last obstacle in running the wheelchair lies in the right motor, which is broken. We have begun to open up and explore the right motor, and our team is also focusing on the joystick control to allow the motors to move correctly. we also made an inventory of the joysticks that were donated to us listed below and began to look into using the connector from the existing wheelchair joystick and replacing it with another because our existing joystick is broken, there are some pictures below of the insides of the joysticks. it has been difficult finding information on what the wires do at the connection because they go directly to a an unlabeled circuit board, making the transfer of connectors difficult.

This is what I found the wire combination to be, there is no wire attached to the middle plug.

this is the wires coming from the original circuit board, we need to find where the connections come from and replicate them from another working joystick controller.

12/6/12

we opened up the right motor and looked at all the major components of the wheelchair in order to find the problem with the motor and documented it | here]. We started by opening the gear box and seeing if there were any dibree in between the gears and did not find anything and looked at the connection between the actual motor and the gear box and could spin the gear box on its own so we know the gearbox is working. after confirming the actual motor was the problem we opened up the back and saw how the brake worked and opened up until we saw the coil of wires which is the crank shaft of the motor and we found a broken connection between the brushes and we soldered the connection and put the motor back together. We have gotten the right motor to successfully work again and connected both motors back to the wheelchair. Then, we plugged both 12 volt batteries back into the frame of the wheelchair and also reconnected the chair back to the frame of the wheelchair. we documented the connection the joystick made with the motor controller and the color coded wires.

The diagram I made of how the wheelchair connections work

Here we can get a good look at the internal system of the right motor

This is the opened gearbox of the motor.

Decision List

List all formal decisions made with links to their documentation such as a decision tree or decision matrix.

Material List

| Joystick inventory]

arduino

Software List

Arduino IDE

Time

27 hours 57 minutes

Tutorials

| Battery charging tutorial]

| Opening the motor]

Previous work on wheel chair

[| MKVI Quad pulse documention]

[| Wire diagram of wheel chair]

Next Steps

Make a decision on what rout to take on controlling the wheel chair i.e faking the joystick with the arduino or bypassing the brain straight to the motors with a motor shield to control the wheel chair.

1. Make a replacement joystick that uses the existing electronic controller

2. Bypass the controller and use an Arduino or computer to run the motors

3. Begin creating arduino programs that will drive the wheelchair's motors