Abstract: To maintain alignment of a band of fiber tows as it travels between a source of such tows and a fiber placement head in a computer controlled fiber placement machine, a pair of redirect rollers are provided, at least one of which is automatically and drivingly swivelled by an amount related to commanded movement of the fiber placement head relative the source of tows so as to maintain alignment of the fiber band between the source and the fiber placement head such that a vector normal the fiber band and across the width thereof is parallel the longitudinal axis of rotation of the redirect roller as the fiber band passes thereover.

Abstract: To maintain tension on a fiber tow as it travels between a spool of the tow and a fiber placement head in a computer controlled fiber placement machine, closed tension loop servo control tow velocity feed forward is provided to control spool rotation so as to not only provide closed loop tension control but to also cause rotation in anticipation of expected tow movement such as due to tow payout upon commanded movements of the fiber placement head. Gain scheduling based on spool radius is also provided. Additionally, a compliant roller is provided to reduce tension dips and spikes from disturbances on the tow, and an inner velocity loop is included with the closed tension loop to provide more effective control of tow tension. The servo control is reconfigurable into an open or pseudo-closed loop mode with a safety low power supply to slowly reel-up slack tow after tow threading, for example, and to otherwise maintain low tension on the tow to hold it in the machine while allowing servicing thereof.

Abstract: An apparatus and method is disclosed for controlling a motor of a machine to move a member at a predetermined velocity. Specifically, a gain factor included in generating a velocity command signal to the motor is dynamically adjustable in accordance with a relationship between the actual following error of the member and the desired following error at the commanded velocity to thereby compensate for drifts in the drive system electronics. The gain factor for a plurality of members may be similarly dynamically adjusted whereby the path of an application point coupled to all the members is accurately controlled. The invention is also suitable for controlling movement of distal ends of a gantry to eliminate or reduce skewing of the gantry member.

Abstract: An apparatus and method is disclosed for controlling motion of a tape dispensing apparatus or the like in response to both computer change in position signals and proportional and integral tracking error signals to maintain a desired conformal relationship between the tape dispensing apparatus and a contoured surface. The level of responsiveness to computer change in position signals versus tracking error signals is adjustable depending upon the severity of the contour so as to optimize servo tracking where necessary.