The driver error is a hardware error code issued by axis control modules if an error occurs in the motor driver logic. Oftentimes this hints to a blocked or overloaded axis. This error should only occur for BLDC axes.

Check the robot control log file for extended error information, particularly one of the following codes:

Message	Explanation
No free rotation	Axis could not rotate during alignment; Check for a blocked axis, resistance, misaligned linear rails, heavy load, motor current settings,...
Collision during free rotation check	See "No free rotation"
Velocity error	Axis was commanded to move faster than possible by the motor controller; Check the axis configuration, especially the gear scale value.
Driver low align	Too many failed attempts while aligning; see "No free rotation", check e-stop, fuses, wiring,...
Alignment failed	Check e-stop, missing current, low current settings, blocked axis, resistance, misaligned linear rails,...
Alignment failed [...] due to missing current or current sensors not init'd	Try re-enabling the motors; see "Alignment failed"
unknown error message	Any error that is not understood by the software yet, this may occur with new features. Contact support for more information.

Common Causes =

For BLDC gantries the most common cause is an axis that can not turn because it is overloaded. Usually because linear rails are not aligned correctly, the carriage can not move easily or the tool/object is too heavy. It can also be caused by a motor brake that does not release (check its amp configuration, wiring and whether voltage is applied at the brake output connector at the motor module or the brake relay.

For other BLDC axes, e.g. the igus ReBeL similar issues can occur. Check whether the axis is blocked or overloaded; a mechanical defect can cause the driver error as well.