Corrected from:
- Library: L_MC4P_RoboticHandling (FAST Motion) V03.12.00.85
(contained in PLC Designer V03.12.00.177 and higher)
Response of the new version:
Position overflows are handled correctly and there are no more erratic speed characteristics that may lead to a response of the monitoring functions.
What happens?
Incorrect handling of position overflows via the positions […, -900°, -540°, -180°, 180°, 540°; 900°, …] with speeds >2°/PLC cycle for rotary ACS axes of axis groups.
This leads to an incorrect setpoint calculation in the following cycle, as a result of which the following error monitoring function or the maximum speed monitoring function may respond and the axis may be decelerated to standstill.
When does this behaviour occur?
The behaviour occurs when using an axis group from the L_MC4P_RoboticHandling library.
During a movement (MC_MoveLinear... ,MC_MoveCircular... or, TM Pick&Place), a rotary ACS axis of an axis group overtravels one of the following positions: […, -900°, -540°, -180°, 180°, 540°; 900°, …].
When overtravelling the position, the axis speed is > 2° / PLC cycle (e.g. >2000°/s with a cycle time of 1ms)
Which products are affected?
- Library: L_MC4P_RoboticHandling (FAST Motion)
(contained in the PLC Designer)
Short-term measures:
General axis groups:
Avoid axis speeds >2°/cycle, when overtravelling the positions +-180°, +-540°, etc..
Belt kinematics axis group:
Reduce the gearbox ratio in the axes e.g. by a factor of 10 (after this, the gearbox output will virtually turn slower by the set factor).
Eliminate the factor again via the feed constant of the 'Beltkin' axis group (factor 1/10). In this way, the error limit can be shifted to axis speeds that are not used in the application.
Evaluation/recommendations: