Changing Speed of Motors?

Simple question: Is there any way to change the speed of the motors (revs per min)? Is it defined in the sanguino sketch or is it defined by the pi talking to the stage?


When you connect to the sangaboard via a serial connection you can set it with the according commands.

“min_step_delay” and “ramp_time”. They are written to the EEPROM and loaded when the board boots up. So if you set it once, your board then should run the motors at a different speed.

I don’t know if it can be set from the OFM frontend software or if is overwritten. I couldn’t find any of those commands in the openflexure_microscope_server repository tho.

Ah okay! Thanks a lot, I’ll give this a go :slight_smile:

If you put in faster settings, do check that the motors do not miss steps. The motor has to reach its new position for each step before the next step, otherwise it will be pulled back instead of forward, or just stay where it is. The motor controller has no way of knowing whether the motor actually moved, so missed steps end up with the stage not reaching the position the software thought it was sent to.
The default settings are about as fast as the usual little steppers can reliably move.

If anything I need them to move a little slower, so this shouldn’t be an issue. Thanks for the heads up though.

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