Very large raw present velocity values from XM430-W350-R Motors

I am using the XM430-W350-R motors, and when receiving the present velocity values using the dynamixel python SDK, I sometimes get very large values (over 10e8). This has occurred in the following scenario: We have a quadruped robot and it’s in stance mode (all motor joints should be locked and not moving and the robot is simply standing). When recording the present velocity values, the values are zero (which should be expected), but I sometimes get these large present velocity values when I push/pull on the quadruped’s leg (I don’t use very much force). The present position values however, are correct and I haven’t seen this issue with the position.

I’ve heard from others that they also sometimes get these strange and very large values on occasion, so I would be inclined to think it’s not an issue with the motors being broken somehow. Is there a way to fix this issue?

Any help would be greatly appreciated,

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Hi Alex,

This is because DYNAMIXEL uses two’s complementary for negative number.

See the ticket raised at github.

It may help,


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