needing help to connect a 2-pin rc-car steering motor to an adafruit pwm i2c controller

So I saw a neat project on a magazine about controlling an rc-car wirelessly through a raspberry pi, using pwm.

I ordered everything I needed, mainly an i2c controller, and I started working on it. i am using a clone of the adafruit controller instead of a real one, because it was a lot cheaper, though the functionality remains the same.

Now, I have a problem. The article says that I need to connect the steering motor to the 3 pins on the adafruit controller, which are labeled power, ground, and PWM, but my motor only has two wires, so I have no idea what they do, or what to do next.

I do not have another rc-car to do this on. How do I connect the motor to the controller? do I need to get a different motor?

Thank you for your help!

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beacon_dave over 7 years ago

Not sure from the photo if your steering is actually a DC motor or a spring loaded solenoid. Does the steering spring back to centre if the wheels are pushed and let go ?

You will also likely have problems with your speed motor as the way you have shown it connected it will result in 'max speed' in one direction.

It looks like you may need a different controller or add a dual H-bridge motor driver to your PWM controller.

The existing Adafruit controller is designed for controlling servo motors or dimming LED's using a PWM signal.

You can use the PWM output however to drive the enable pin on an H-bridge driver like the L293D which will give you motor speed control and then use four GPIO pins to control the direction of each motor independently for forward/reverse and left/right

https://learn.adafruit.com/adafruit-raspberry-pi-lesson-9-controlling-a-dc-motor/lm293d
https://learn.adafruit.com/adafruit-arduino-lesson-15-dc-motor-reversing/an-experiment
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tlucas756 over 7 years ago in reply to beacon_dave

Thank ypu for responding!

the motor might be a DC motor, because it does not spring back when I push the wheels.

Also, I have to find a quick solution to this, as I have to show this to my electronics teacher next week, and I can't get any new components in time.

Also, I still have the original controller chip that came with the car when it was new - It's a Realtek RX2C A5081 35T, but in order to make my project work, I can't add that chip in.
What I was thinking was to get one of those cheap arduino servos (that have 3 pins) and replace the one in my rc-car, though I'm not sure if that would work.
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tlucas756 over 7 years ago in reply to tlucas756

one of these:
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