Motor port B running forever

[maceron4444]

I've managed to get the Print3rbot up and running with all the required software, but when I run the writer.py code whatever's connected to motor port B will just run indefinitely regardless of what image I try to draw.

Has anyone else had this issue? Does this happen when the svg image doesn't have any paths? I'm most likely missing something simple here.

Thanks.

[cavenel]

Port B should be connected to the motor lifting the pen. It will indeed run indefinitely when started for calibration purpose. It will stop turning when it will be stopped against the red lego piece (http://img.rebrickable.com/img/pieces/elements/4227155.jpg):

self.mot_lift.rotate_forever(speed=-50, regulate='off')
    time.sleep(0.5)
    while(abs(self.mot_lift.speed) > 5):
        time.sleep(0.001)
    self.mot_lift.stop()

Basically: run forever while speed > 5. When speed < 5, stop the motor, reset the position and consider the motor calibrated.

Ports A and C should be connected to the 2 motors (left and right) giving the pen's position.

[maceron4444]

Ahh I see now, how to the arms calibrate themselves? Do they move towards the bottom of what would be the image as every time I run the code now, the arms will contract towards the EV3 brick and try to keep going despite pushing the touch sensors.

I need to adjust the arm length in the code as I don't have all the parts required to build the print3rbot to the exact spec as shown in the instructions.

Thanks for the help so far :)

[cavenel]

I guess I can close this as it has been solved :)