synthetos / TinyG

Affordable Industrial Grade Motion Control
https://github.com/synthetos/TinyG/wiki
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G28.2 move starts, stops, and then continues #270

Open natd89 opened 3 years ago

natd89 commented 3 years ago

When I run the homing command the axis moves ~5cm pauses and then resumes the motion. If I click the limit switch between when it first starts moving and initially pauses, the motor stops turning and then resumes motion before I let go of the limit switch. When I let go of the limit switch the motor stops and the board is not homed when I check $home.

If I wait long enough after the G28.2 command is sent, the motor will start running, pause for a little after moving a short distance and then resume motion. If I press the limit switch after it resumes motion the axis homes correctly.

My concern with this is that if I try homing the machine with the carriage too close to the limit switch the machine will crash because there isn't enough space for the axis to start moving, pause, and then resume/start the homing sequence. Any idea why this is happening?

duchonic commented 1 year ago

We use the TinyG for the Liteplacer.com project. We had the same effect and i think it's because the Max Switch is On. If the Max Switch is On the Axis will move out of the Max Switch before homing with the Min Switch.

Our problem was that the Max Switch was not wired correctly (wrong logic with normaly closed). You can also try to disable the Max Switch for homing.