Create an RC Vehicle
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Overview
Theory
An android device is loaded with an app that communicates with RC vehicle via bluetooth.
The vehicle has an atmega (arduino) processor which reads the bluetooth command and sends pwm
pulses to the h-bridge.
A adjustable step-down power supply converts the 8V input to 5V output needed by the atmega controller.
The 8V is also passed to the h-bridge so that it has the maximum power possible to drive the motors.
Parts List
- 4 wheels with motors ($10): http://www.banggood.com/4Pcs-DIY-Car-Model-TT-Mot...
- 8 inch by 10 inch sheet of acetate 0.09 thickness ($4). Found at Menards
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Slide Switch ($0.75) http://www.ebay.com/itm/5x-Black-Mini-Miniature-5...
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Some wire (about 4 foot, 22 gauge is fine)
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Bluetooth control module https://www.instructables.com/id/Bluetooth-RC-vehi... from paulware@hotmail.com
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Hot Glue (about 1 stick)
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Battery holder case for 2x18650 batteries with wire lead($0.75): http://www.ebay.com/itm/BATTERY-HOLDER-CASE-FOR-2...
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2 x 18650 batteries ($2.36) http://www.ebay.com/itm/3-7V-6000mAh-18650-Li-ion...
Total parts cost (about) $36
Tools list
- Electric Dril
- Drill bit for plastic/glass (Available in Home Depot)
- Soldering Iron, solder
- Hot glue gun
- Battery charger for 18650 lithium ion battery
- Voltmeter to adjust the voltage
- Small flat edge screwdriver to adjust voltage
- An android device
Steps
- Drill holes in the sheet of acetate per photo
- Wire the motors in "parallel", don't worry about color of wires.
- Hot Glue the motors to the acetate sheet.
- Screw the battery holder into the acetate holes (use 6/32 screws) , and glue in the switch.
- Feed Motor wires through the holes.
- Connect the power supply to the battery and adjust the voltage output.
- Connect the other controller components
- Load the mit app inventor 2 program "jeneral".
- Create or acquire a bluetooth controller. See this instructable: https://www.instructables.com/id/Bluetooth-Control...
- Pair with the bluetooth controller (password=1234)
- Run the jeneral android app
- Drive the vehicle.
Downloads
Drill Holes in the Acetate Sheet
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Drill holes in the sheet of acetate per photo
Wire the Motors
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Wire the motors in "parallel", don't worry about color of wires.
Place a bit of hot glue at each solder joint to protect this weak spot
Hot Glue the Motors to the Acetate Sheet.
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Hot Glue the motors to the acetate sheet and push the glue through the holes, this creates a very strong bond.
Screw in the Battery Holder
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Screw the battery holder into the acetate holes (use 6/32 screws) , and glue in the switch.
Careful: The switch may pop out before the glue dries.
Feed the Motor Wires Through the Holes
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The order should be (from left to right):
Lower Right, Upper Right, Lower Left, Upper Left
Following this order will ensure that the car responds properly to the bluetooth controller
Connect the Power Supply to the Battery
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Connect the power supply to the battery and adjust the voltage output, this will require a small screwdriver
and a voltmeter. The output of the power supply should be 4.95V - 5V
Connect the Other Controller Components
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Connect the bluetooth controller according to this instructable:
https://www.instructables.com/id/Bluetooth-RC-vehic...
You can also order one from paulware@hotmail.com
Note the jumper wire from + Battery pole to h-bridge input
Load the mit app inventor 2 program "jeneral".
From this instructable:
https://www.instructables.com/id/Bluetooth-Control-RC-Tank-Android-Arduino/
Pair your android device with the bluetooth receiver (password=1234)
Run the jeneral android app to drive the vehicle