Automatic tuning and control of a linear drive based independent cart system with initial value compensation

A method for controlling operation of at least one mover in an independent cart system, the method comprising the steps of:

• identifying a desired position at which the at least one mover is to be located with a controller;
• generating an active command with the controller for the at least one mover to travel to the desired position along a track for the independent cart system;
• receiving an active feedback signal at the controller, the active feedback signal corresponding to the active command;
• determining an error signal as a difference between the active command and the active feedback signal with the controller;
• providing the error signal to a control loop within the controller;
• generating a reference signal with the control loop as a function of the error signal;
• generating a position feedback signal, corresponding to a present location of the at least one mover, with a position feedback system mounted to the track;
• reading the position feedback signal with the controller;
• comparing the position feedback signal to the desired position with the controller;
• indicating the at least one mover is at the desired position;
• reading a compensation value from a memory in communication with the controller, wherein the compensation value is neither a function of the active command nor a function of the active feedback signal;
• adding the compensation value to the reference signal one time to generate a modified reference signal when the at least one mover is at the desired position;
• and
• using the modified reference signal to control operation of the at least one mover.

A method for controlling operation of at least one mover in an independent cart system, the method comprising the steps of:

• reading a position feedback signal with a controller from a position feedback system mounted to the track, wherein the position feedback system is configured to generate the position feedback signal corresponding to a present location of the at least one mover;
• comparing the position feedback signal to a desired location;
• indicating the at least one mover arrived at the desired location;
• adding a compensation value to a reference signal one time within the controller for the at least one mover when the at least one mover arrives at the desired location along a track of the independent cart system in response to a motion command;
• determining a maximum amplitude of a settling error for the at least one mover arriving at the desired location with the controller;
• comparing the maximum amplitude of the settling error to a stored amplitude of the settling error with the controller;
• when the maximum amplitude is greater than the stored amplitude adjusting the compensation value to a new compensation value;
• and
• adding the new compensation value to the reference signal one time within the controller for the at least one mover when the at least one mover next arrives at the desired location.