Introduction: WSU GoBabyGo Modification - 12V Jeep With Big Mac Switch

About: Students at Wichita State University run a program that modifies off-the-shelf ride-on toy cars for kids with disabilities. Our cars feature more technical builds with joysticks and arduinos. We post our instr…

Fall 2018

Step 1: Materials Needed

Some or all of these materials may differ to some degree from what we initially specify here. Nevertheless they are very similar and will perform the job with some minor differences in installation.

● Car-Best choice Products 12V Kids ride on truck

https://www.walmart.com/ip/Best-Choice-Products-12...

Remote-Control-3-Speeds-Spring-Suspension-LED-Lights-AUX-Pink/119258024

● Big Red Twist Switch ”Big MAC BUTTON” -

https://www.amazon.com/AbleNet-Big-Red-Twist-Switc...

○ This is the method of actuation. Rather than utilizing the traditional car pedal, this switch will be installed on the steering wheel to implement acceleration.

● Single Throw Toggle Switch(SPST) -

https://www.amazon.com/SPST-Single-Throw-Toggle-Sw...

○ This is the emergency stop switch that will cut off the power source.

● Single Pole Double Throw Relay -

https://www.amazon.com/ONLINE-LED-STORE-Pack-Inter...

○ The Big big red twist switch button is rated for 0.5 A while the vehicle is rated for 10 A. The relay is rated for 40 A. This will help to prevent any fire hazards.

● Hip Support -

https://www.amazon.com/VIAHART-Yellow-Adult-Swimmi...

○ We will alter and install a kickboard in order to make the seat more ergonomically suitable during the vehicles operation

● Lap Belt -

https://www.amazon.com/dp/B07H9SHKXC/ref=cm_sw_r_c...

○ This belt will replace the manufacturer installed belt. It is structurally better

Step 2: Assembling the Vehicle

Before you assemble the vehicle, it is advised that you read all directions in the Instruction manual that come with it. After the assembly is completed, the biggest thing is to make sure that the car is fully operational and working as you expected it to. The process below will be specific to our vehicle.

Hints

  • After/while reading the directions ensure that you have all the materials needed for assemble before you begin.
  • We held off on installing the windscreen and side mirrors till after all alterations to the ride on vehicle was complete to avoid scratches/damage to their delicate parts.

Step 3: Installing Emergency Stop

This switch is a power switch. It will either allow power to flow to the motor or cut off all power to the motor.

1. Decide on a location that will be most logical for the emergency switch to be placed.

2. Mark and drill a hole through that part of the car.

3. Connect the live and ground (on and off) wires to the respective places on the switch.

4. Connect the live and ground wires from the switch to the live and ground from the battery.

5. Cover any open wire with electrical tape and secure the wires along the inside of the car.

6. Run the switch through the hole and screw on the cover that comes attached.

7. On the outside of the car, make sure there is a visual indication of on/off.

Step 4: Install "Big Mac" Switch on Steering Wheel

This will be the biggest modification that is done on the vehicle. The specifications of the

use of the car require actuation by hands thus the manufacturer installed pedal will be

discarded. The Big Red switch(well yellow in this case) will be attached to the steering

wheel.

Disassemble the existing steering wheel.

1. By disassembling the steering wheel, you now can remove the front cover of it by

removing a couple more screws.

2. Measure the big red button and make sure it can fit securely into the steering

wheel.

3. Trace the button and make a cut out (this can be done via dremel tool).

4. Try fitting the button into the steering wheel, if this does not work, you can always

cut off more material but be careful when cutting material because if you cut too

much, the button will not be secured.

5. Assemble the front cover and back side of the steering wheel back together.

6. Reattach the steering wheel to the car.

N.B. The button is rated for 0.5A while the car is rated for 10A. This is an issue because if you just allow the full power to go across the button, it will create some overheating and may cause the wires to catch fire and that is a hazard that should obviously be avoided. However, depending on the vehicle selected, it may have a built in relay (as does in our case).

Step 5: Wiring Big Mac Button

The Big Mac button will need to be wired into circuit.

1. Cut the wires previously running to the foot pedal. Strip the ends of the wire to allow connection to the wires from the Big Mac button.

2. Strip ends of Big Mac button and twist together with ends of the wires stated in step 1.

3. Secure connection with twist on wire connector.

4. Test secure connection of wires by tugging on them. Make sure the connection is tight so it doesn't come lose over the years of use.

Step 6: Customize Fit

Main support to fulfill design specifications is for the lower body

1. With measurements, decide on a place to install a lap belt.

2. Cut out the holes from the plastic and slot the belt through the back or just re-position it from preexisting holes.

3. On the back side, secure the belt in such a way so that it will be structurally stable. How our belt was secured was by screwing the belt into the car. This was shown to be sufficient.

4. Depending on your client, support modifications will be different. For us, we have to make support for the back.The way this was achieved was by using a pillow that we stuffed and structured using PVC pipe. The PVC gave it firmness while the pillow itself was cushioning.

5. We wanted the support to be adjustable rather than permanent. We achieved that through the usage of Velcro. Two strips were added down the side of the chair and the other side of the Velcro was attached to the support. This allowed for the support to move up and down freely.

Step 7: Customize the Car (Optional)

Before delivering the car to our client, Faith, the final step in designing the car will be customizing the car to fit her own personal style. After meeting with Faith, her family, and receiving some details from her physical therapist, Faith was described as a very girly girl. So the cosmetic changes being made to the car will be the addition of Frozen and princess stickers, changing the color of the Big Mac Switch from red to yellow, and a customized license plate (instructions below)

1. Measure dimensions for license plate.

2. Design license plate in CAD design program. For us we did our clients name, Faith.

3. Using an Epilog Helix Laser Machine, 50 Watt, the engraving is made for the license plate.

4. Mark and drill holes in the ideal spot on the car for the license plate placement. Secure license plate by using screws and and hex nuts.

Step 8: Delivery Day

The final step in the process is delivery of the completed car to the client, Faith. Needed back support modification was necessary for our team on delivery day. When Faith was placed in the car she sat too far away from the big mac button (image 1 in this section). A kick board was added to back of the seat.

1. After measuring kick board cut to fit the dimensions of the seat.

2. Two strips of Velcro were added to both the front and to the back of the kick board. We added the Velcro to allow for the removal of the additional shift forward as our client grows over the years since she is already very tall for her age and will be using this car for the next several years.

3. The kick board was attached to the seat and the back support was reattached to the Velcro on the front of the kick board. This still allows for the freely adjustable feature of our back support.

Step 9: Installing Relay (Situational)

Tentative Steps

This step was not required for us personally but you will need a relay if your car does not have one pre-installed.

1. Decide on a location that will be most logical for the emergency switch to be placed.

2. Mark and drill a hole through that part of the car.

3. Connect the live and ground (on and off) wires to the respective places on the switch.

4. Connect the live and ground wires from the switch to the live and ground from the battery.

5. Cover any open wire with electrical tape and secure the wires along the inside of the car.

6. Run the switch through the hole and screw on the cover that comes attached.

7. On the outside of the car, make sure there is a visual indication of on/off.