I had a long career serving on all manner of vessels as a Engineer
, I always kept eyes out for ideas that would be suitable on a sailing vessel.
The idea here is nothing new to Ships, but I have never seen the idea applied to small yachts.
The advantage of Rapson slide is a more efficient tiller in that at low Rudder
angles, the mechanism is quicker in response to Autopilot
and at large angles less Pressure is required to your linear actuator.
I did some calcs, and for a given time (15Sec) to hard over ~ 30Deg, the maximum pressure is reduced by 15%, at low angles the Pressure is up a bit but still modest, the response is improved by 9%. (Compared to Whitlock method)
Not much, but given that on a yacht, autopilots consume lots of power, quicker action could reduce the amount of total power consumed, but the main advantage would be less wear and tear as in particular linear drives are more likely broken by the high force at max helm
I think that sailing vessels never went this way as a good helming was part of the fun and sailers were tough, when the first autopilots were produced for sail boats they were a simple retrofit. Believe this idea would improve feel and less likely be overcome by real bad unbalanced helm
A modification to make this work, is not difficult, the tiller can be made with a slider on solid round tiller or my preferred method, a forked tiller, as in the accompanying sketch, I also think a quadrant plate could have such a slide mechanism bolted to it.
Interested in your comments, particularly those that have had broken steering