I have almost finished building one of Model Slipway's Rescue Boats which is going to my 6 year old Grandson for Christmas. It is currently powered by a 385 motor on 6 volts. I have a feeling that this may be too much for my Grandson, especially as we need to moderate the speed of fast boats to avoid upsetting the Angling organisation who control the lake. His transmitter does not have EPA so rather than buy a Servo Morph from Action, I decided to build my own Arduino version.
The first photo shows the development on the breadboard. The second two show the final version on an Arduino Nano and small piece of stripboard. As this is only required to limit maximum speed, the Sketch is quite simple. I have ordered an ATTiny 85 controller which should have enough capacity for this and is even smaller.
Barrie