Cheap radio control car low frequency PWM Arduino control proof of concept (part 2)

This is my second video showing my litle hack in action. When I did the last video the only thing that I had implemented was the forward direction. Now with little effort I've also added the backwards direction and the steering control.

The PWM frequency is 10 Hz approx. I've tried rising it to 20 Hz but the response becomes very poor and I think that is because of the low transmission rate the controller uses.

At 10 Hz the PWM works great for back and forth movement and I can get different speeds fom the car but the steering control behaves in a binary fashion and it is not possible to have the wheels in a fixed direction other than full turn to the right and full turn to the left.

I think the problem here is the heavy damping and the low viscous friction of the steering mechanism and I don't see a easy way of solving this, maybe dust will someday do the trick.

Now the next thing I will try to do is to control the machine from a different computer than the one that has the arduino attached. Also I'll release some lines of code soon to help anyone interested in building something like this.

Category:

Science & Technology

Tags:

• arduino
• toy
• rc
• car
• remote
• control

[cornboy3]

How do you go from the arduino operating voltage to the 9v motors without a signifigant power decrease or using relays?

[Minipimmer]

@cornboy3: No, as I told johved, what I did was to control the remote controller through the arduino, tha car was not modified. The voltage levels on the remote controller where TTL and it's ground was connected to the arduino ground.

No one should ever try to power a motor directly from the microcontroller pins. Also relays from my point of view are not an option (durability etc). If I needed to do that I'd use a transistor H-bridge (4-Q operation) or at least a single transistor bridge (1-Q).

[Minipimmer]

No, as I told johved, what I did was to control the remote controller through the arduino, tha car was not modified. The voltage levels on the remote controller where TTL and it's ground was connected to the arduino ground. No one should ever try to power a motor directly from the microcontroller pins. Also relays from my point of view are not an option (durability). If I needed to do that I'd use a transistor H-bridge (4-Q operation) or at least a single transistor bridge (1-Q).

[johved]

did you hook up the remote controller to the arduino or do you have a custom radio transmitter thingy

[Minipimmer]

The remote controller has digital on/off controls, so I connected cables to each controller switch and I force these signals from the arduino.

[jlspma]

nice