pic: 221 Robotic Systems Swerve Demo Bot Steering Feedback

[Gdeaver]

I noticed that the sprocket on the steering drive is not the same diameter as the sprockets on the pivot modules. That combined with the dead band of the potentiometer would lead to some tough programing problems. I don't see any indexing on the steering system. So I want to know how are you guy's handling these problems? We used the window motors also. We have one for each module. Our steering sprockets are 1:1, so the value from the sensor always matches wheel orientation though 360 degrees. As to absolute rotary position sensors, I have not found any company that makes a classical potentiometer that has 360 degree mechanical and electrical ratings. The US Digital MA3's mentioned would be good for this application. We used the Cherry AN8 series. The Cherry AN8's are IP67 and automotive qualified. By being Automotive qualified you gain reverse polarity protection and higher ESD protection. Some teams have had problems with MA3's and ESD. They also are 0 to 5 volt and the out put is sloppy at the rails. The AN8's are 0.5 to 4.5 volts and have a sharp saw tooth slope.