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I own an iRobot create2 on which I am planning to implement a control algorithm. After playing with the different drive commands, I noticed that changing the desired velocity values marginally doesn't seem to do anything.

Even the Drive PWM command that ranges from -255 to 255 seems to have an internal granularity that is bigger than 1.

In this video the create seems to change its driving direction nearly seamlessly, which I am not able to reproduce with the described behavior.

Does anyone have any suggestions?

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    $\begingroup$ Can you describe in more detail the behavior you are seeing? Can you post a video? Can you post your code, or some simple test code that demonstrates the issue? $\endgroup$ – Ben Jun 21 '16 at 13:12
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In my brief stint working with the Create 2, I noticed the same thing. Specifying very low velocities doesn't work very well, and small increases don't seem to do anything up to a certain point. This non-linearity in the response of the motors to the inputs can likely be explained by resistance (stiction) of the motors, which must be sufficiently overcome.

To get past the resistance, you could try supplying large jerk initially, then decreasing acceleration until the desired velocity is achieved.

I cannot speak to the velocities or controls used in the video, but I will point out that whenever the velocity (linear or angular) changes, there appears to be a rapid acceleration, which is what I have suggested.

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