Arneson surface drives are extremely efficient and durable.
When used in a diesel application it is important to adjust the drive trim angle to obtain the proper load on the engine.
The most common solution for this used on most boats is an old school cable & rheostat setup, The cables have a lifespan and in saltwater must be replaced frequently. And they are not very reliable or accurate. As there is no tiller arm or physical connection for steering the same setup is used for rudder position and autopilot feedback.
Until recently there was no reliable or cost effective way to solve this problem. We recently developed a retrofit for existing cylinders that puts an inductive position sensor inside the cylinder itself. It is completely isolated from the water and provides a 0-5v signal with a position accuracy of 1%. This signal is exactly what most autopilots need. There are also digital and LED position indicators compatible with this signal or it can be converted to NMEA 2000 to dispaly trim snd rudder positonon on a MFD