Roland -180° turn blocked !

[primus]

No feedback.

Maybe the motor tunred.....maybe not?

The correct signal was sent for movement, but did it actually happen??

The Roland would not know. It only knows where it is during home position.

 

[zero_zero]

If this is the motor type you are talking about maybe it can be done:
Stepper motors enable precise positioning without needing sensors to measure motor position. Each pulse to a stepper motor turns its shaft one step which for many steppers is 3.6 degrees. One hundered pulses will turn a 3.6 degree stepper exactly one revolution.

If the software calculate the pulses to control the position of the clamp then why not use it to avoid collision or just stop the machine?

The Roland mill is using Nema 14, 200 steps/rev steppers ( 1.8 deg resolution ),looking at the drive elecronics and reduction gears I believe that they're avoiding any microstepping to maximize torque...
You're right about step counting to know the position at any given moment, hovever if the clamp is obstructed the stepper motor will stall, the firmware will keep sending the pulses not knowing that the rotor isn't turning at all...that's when you get the axis position lost error... With this design the only way to detect an obstruction is to monitor the drive current. ..I don't think that the drive circuit would support that...meaning that a firmware upgrade won't solve this issue.

 

[EGE]

Glenn wrote:"the short term solution is nesting to avoid falling chunks. Long term, lets see what can be done to improve the design so falling chunks are less of an issue." The DWX-50 has some limitations.
Instead of trying to change the machine because you have a problem with material falling in the tray, why don't you try to find a solution so that material do not fall ?

Marcus wrote: "Check and double check your nesting. If pieces are falling out and breaking burs/zirconia framework. Its a user error.
Zero wrote: "Shouldn't be any pieces left unsupported

You did not answer the question about what CAM you are using, but if you use GO2dental, then there are no parts of your block will fall. No need to check the nesting, no need to simulate, no user errors : GO2dental cares for this, it will machine automatically any part of the nesting that is not supported by a sprue.