I am facing an issue in regards to a router with 3 axys - X, Y, Z, while Y gantry has a further slave - A.
All motors have absolute encoders.
The system is Delta - the controller (NC300), the drives (Asda A2) and the motors.
My issue is that even though the gantry is quite rigid (steel, about 100kg), when the system is stopped, the gantry can be moved by hand, and the Y and A get out of sync.
If I move by hand the X axis, the absolute encoder will know the position even after restart, as it is normal. But even if this is the case for Y sometime, in some cases the Y motor turns more than the A motor when moving the gantry by hand, and I will get an error when starting the system.
In my view the A (slave) axis should reposition itself in sync with the Y axis automatically of the system detects this.
I opted for absolute encoders to have this benefit of no needing to go through a homing procedure.
One option I consider it to have on the Y and A axis motors with brakes, so when stopped the gantry cannot be moved. Of course that will not come cheap, but not having to do the homing is a great benefit.
I would appreciate inputs from anyone having a similar setup, and how it handles the situation of accidental moving of the gantry and a desyncronization of the master-slave motors (and encoders).
Using home switches defeats the purpose of absolute encoders.
Also, important to know that X and Y axis must be squared, and this procedure is very time consuming
Marius