Absolute zero position for Dynamixel XM430-W350-R: How to change it?

[jcarlos]

I have recently started working with Dynamixel XM430-W350-R servo motors. In 'position mode' the motor offers an accuracy of 4096 points for a full 360º rotation (with an absolute encoder).

Therefore, in order to arrive at a specific position, a value between 0 and 4095 must be indicated. However, if for example I am at 1, and I want to get to "-1" (by the shortest route) I can not. Instead the servo motor should move up to 4095 making a turn of almost 360 degrees. I mean, it looks like zero ("0") can't be crossed. True?

My question is: Is it possible to "move" the zero position to an arbitrary position (by means of a calibration procedure, reset...)? How?

If it is not possible (!), what is the right approach?

Thanks!

JC

[jwatte]

The documentation for Dynamixel protocol 2 (used by the XM430) talks about this. There is, for example, a "multi turn" mode. Or you can turn on "wheel mode," move forward, and then turn back on "joint mode." (That's what you had to do in the version 1 protocol, at least for certain versions)

If you read through the protocol description, you will find the options they have for this case: http://emanual.robotis.com/docs/en/d...of-eeprom-area

[jcarlos]

Thank you so much for responding so quickly, jwatte . Yes, theses solutions you propose are feasible, but I don't really need more than 360 degrees. The Homing position parameter has turned out to be just what I was looking for.

JC