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how to make a microcontroller potentiometer control a servo and motors on my rc lorry for rear wheel steer? Answered

Hi Guys,

Im a keen modeller and build rc 1:14 scale trucks, I'm trying to build a trailer as many have done that uses a potentiometer which is turned when the lorry turns and the trailer follows through the tow pin, this then turns a servo that makes the rear wheels of the trailer steer creating rear wheel steering. the servo doesn't start turning till the pin is turned about 5 degrees either way, allowing the lorry to reverse easier as the rear steering won't work if not turning past the 5 degrees.

On the trailer it has a detachable neck that is driven by a motor.

Another servo or small motor to lower and raise the loading ramps

Another motor that raises and lowers the legs to support the trailer when disconnected from the lorry.

All of this I would like to be able to control separate from the lorry, so i can press a button and the legs will lower and lorry can drive away without wires going from one to the other.

Ive attached some videos to give you some idea of what I'm trying to achieve

This video has a circuit board that they refer to as E.T.S. Module (electronic trailer steering) This has been made by a fellow member but wants big money for them, it controls the rear wheel steer and neck detach motor, sorry its a long video.


This next video you can see the movement pause, roughly 5 degrees each way.


Im trying to achieve one board that can control the items above and be somehow wireless or link in with my rc gear, Hope you guys can help.

Many thanks


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5 years ago

This simple circuit is used to work a servo motor.