Hi Raymond, today i am realizing that the free servo will rotate uncontrollable, because ardupilot knows only to turn a normal servo left 90 degreed, return it to the center and right to 90 degrees. I think the only option is with a 2:1 ratio. Pulley on motor double size than driven pulley which requires a strong motor! The torque is measured in realation to the 2 pulleys. So if motor pulley is 20 cm and wheel 10, we will have half torque on the wheel. Thats not so bad and the wheel will turn 180 left and 180 right which is good. However it’s not the best setup for sure…
As Darell and Sebastian described in previous posts a position sensor and feedback loop will be needed for a continuous rotation motor.
Well! We will find a way to do this !
So you guys got me digging in the depths of my memory and searching the internet for something I don’t need.
I think this is what you are looking for:
I haven’t messed with them so Id recommend you give the MFR a call but I’m pretty sure you can set them up to be controlled via a servo position using the “Follow Digital Positioning Command”
I’d be curious to know if they are what you are looking for! Let me know!
Yeah I’m running Skid steering. I haven’t made a thread for it. It’s kind of a monster.
Ignore the wheels it’s a boat 
Themis
you have to provide the motor force for the boat to sail at considerable speed.
i am think about building a boat like " Aimy 6 hours 20 min test non stop unassisted" ( utube)
he may be another person that can put us in the right direction
Thanks Darrel! That is something that could work if this motors can accept a PMW from pixhawk. If they can be set to rotate for example 5 revolutions left and right instead of 180 degrees a normal servo does that would be working.
Example: pixhawk outputs 1000μs, turn the motor 5 revs left and right ,instead of -90 +90 degrees.
Your ve done a very serious job with your boat! Congratulations. I can see the float cylinders, wheels are for moving it around i guess? You have done a lot of work!
As i am looking the tekniks motor site another idea came on mind. Probably you can tell if its possible or not. What about hacking a 180 degree servo? If we uninstall the potentiometer from the motor box and attach it on the rudder shaft of the boat? In this way the motor will turn the wheel until the pot reads the desired angle on rudder shaft. Actually we will read the rudder shaft instead of the motor shaft! Is that something worth experimenting?
I’m pretty sure that is exactly what it does.
It certainly couldn’t hurt I suppose. Keep in mind that most servos measure their position with a potentiometer whish is a voltage signal. running a long length of wire between the potentiometer and the servo circuit could cause enough voltage drop to offset or lose the position
Today I experimented with a small servo, disassembled the gears so that the pot was not moving as the motor rotated. I connected the servo to a servo tester and gave it a full turn to the right. The motor started spinning continuously, and I started rotating the potentiometer by hand at a random speed simulating a possible rudder movement. As the pot reached the same position as the servo tester output, the motor stopped spinning.
That is very encouraging- possibly a 360 free rotating servo on the wheel with an external potentiometer on the rudder shaft sounds like a possible scenario, so the ardupilot will function the same as with a small RC boat.
No need for DC motors, motor drivers, and Arduino. Well… that’s a theoretical conclusion for the time being. Waiting for the hardware from Aliexpress to proceed…
here is another option:
more DIY style than the clear path controller, no feed back but the price is cheap.