A method for controlling a stroker actuator, that includes measuring a piston extension length, calculating a piston buckling threshold based on the piston extension length, measuring a piston force, making a determination that the piston force exceeds the piston buckling threshold, and based on the determination, shortening the piston extension length.

Virtual slots are provided to coordinate traffic flow in an independent cart system. Multiple virtual slots are defined along a length of a track for the independent cart system. The track includes multiple track segments, and the independent cart system includes a linear drive system to propel movers along the track. Each of the virtual slots are controlled to travel along the length of the track. The virtual slots are spaced apart at a first distance and are controlled to travel synchronously at a desired speed. Each of the movers is controlled to travel within one of the virtual slots at the desired speed, and each of the movers has a minimum stopping distance greater than the first distance when travelling at the desired speed.

A linear motor system includes a track and at least one movable member coupled to the track and configured to move along the track. The at least one movable member includes a first element, a second element relatively movable with respect to the first element, and at least one movement detector configured to transmit a movement signal. A processing unit is configured to calculate a movement of the movable member, the second element and/or the first element as a function of the movement signal received from the movement detector.

A controller for a linear drive system includes compensation of a reference signal as the mover approaches a commanded position along a track. The compensation value is added once as the vehicle approaches the commanded position, adjusting the reference signal. This compensation allows the controller to resolve to a zero reference signal at the same time the vehicle reaches the commanded position. The amount of compensation required may be automatically determined for a particular vehicle to reduce or eliminate overshoot as the vehicle approaches a station. Initially, no compensation is provided and the controller monitors settling error as the vehicle approaches a station. The compensation value is then incremented and the controller again monitors settling error as the vehicle approaches a station. The controller compares the new settling error to the prior settling error and adjusts the compensation value accordingly.

A method for controlling a stroker actuator, that includes measuring a piston extension length, calculating a piston buckling threshold based on the piston extension length, measuring a piston force, making a determination that the piston force exceeds the piston buckling threshold, and based on the determination, shortening the piston extension length.