This Hall-effect throttle works just like the spring-loaded throttle on a motorcycle. It's ideal for use on electric scooters and Go-karts, etc.

Last month’s DC Motor Speed Controller was designed to work from a joystick or a potentiometer that is normally centred. This has the virtue of simplicity but having the motor speed and direction under the control of a single potentiometer can be a problem in some applications. Therefore, this companion design was produced to allow a potentiometer to control only the motor speed while the motor direction is controlled by a forward/reverse toggle switch.

Furthermore, the potentiometer can be substituted with a spring-loaded motorcycle-style throttle control which
could be just the ideal solution for applications like electric scooters, Go-karts, etc. This throttle control is shown in the photographs in this article.

The motorcycle-style throttle is based on a magnet and a Hall-effect IC to derive a control voltage. The more you rotate the throttle against its spring tension, the higher the control voltage fed to the input of the Throttle Interface circuit.