I have an AR3 built about a year ago. I noticed a lot of nosiy readings from the encoders. After I jog the robot around for a while, the control software will show 'inconsistent encoder value error' and the encoder values drift slightly from time to time. Could this be a shielding problem? I am using unshielded CAT6 cables connecting the robot to the control box and the cables inside the control box are also unshielded. Thanks.
To follow up, it seems the above only happens when I use a 5V external power supply (which is needed to control servos). If I power the encoder and limit switches with teensy +5V, everything works fine when stepper motors are enabled; If I power a servo with external +5V and common ground to teensy, the encoder values keep increasing. Does anyone use an external +5V power supply for servos? Do you get good encoder readings? Thanks.
I also found out that the Arduino and Teensy share a common ground since both are connected to the PC. Could this be an issue? I think according to the manual these two microcontrollers should NOT share a common ground.
The external power supply on the AR3 is just to power the 8 channel relay board. I wanted the controller to have the ability to control multiple relays but I dont think many people are using more than one or two relays so in the AR4 drawings I only show the installation of one relay and a nano board. That being said I would not power the encoders from the 5v supply and only from the teensy and do not have the teensy share a common ground with the other board or power supply. I hope this helps and let me know if you have any other questions.
