Thrust monitoring in a linear drive for independent cart system

A system for monitoring thrust in a linear drive system, comprising:

• a track including a plurality of drive coils for the linear drive system;
• a mover including a drive member for the linear drive system, wherein the drive member on the mover causes the mover to travel along the track responsive to a series of electromagnetic fields generated by each of the plurality of drive coils;
• at least one position sensor mounted along the track, wherein the at least one position sensor is operative to generate an analog feedback signal as the mover travels past the at least one position sensor;
• a controller configured to:
• receive the analog feedback signal from the at least one position sensor;
• sample a plurality of values of the analog feedback signal as the mover travels past the at least one position sensor, wherein:
• each of the plurality of values corresponds to a different position of the mover, and
• the plurality of values of the analog feedback signal plotted with respect to the corresponding different position of the mover define a curve;
• determine a value of thrust generated by the linear drive system as the mover travels between a first position and a second position proximate the at least one position sensor as a function of the curve;
• and
• adapt operation of the linear drive system responsive to the value of thrust exceeding a predefined threshold.

A method for monitoring thrust in a linear drive system, comprising the steps of:

• receiving an analog feedback signal at a controller from a position sensor mounted along a track for the linear drive system, wherein:
• the analog feedback signal varies as a function of a position of a mover traveling along the track,
• the controller receives the analog feedback signal as the mover travels between a first position and a second position proximate the position sensor, and
• an amplitude of the analog feedback signal varies as the mover travels between the first position and the second position defining a waveform for the analog feedback signal;
• detecting a change in the analog feedback signal from a nominal value of the waveform for the analog feedback signal as the mover travels between the first position and the second position, wherein:
• the nominal value of the waveform is stored in memory of the controller, and
• the waveform received from the position sensor is compared to the nominal value stored in memory;
• and
• adapting operation of the linear drive system when the change in the analog feedback signal exceeds a predefined threshold.