초록 ▼

A positioning system for moving a member between positions in time optimal fashion employs concurrent “feedforward”and “feedback”control. The feedforward control system provides major control and the feedback control system provides minor control to correct for deviations between the actual and a no

A positioning system for moving a member between positions in time optimal fashion employs concurrent “feedforward”and “feedback”control. The feedforward control system provides major control and the feedback control system provides minor control to correct for deviations between the actual and a nominal system. The feedback loop may thus be of low bandwidth permitting desensitization to high frequency disturbances or the employment of inherently low bandwidth controlled variables. The “feedforward”control function includes successive portions of opposite polarity corresponding to acceleration and deceleration of the member and also includes a subtractive velocity related component. This function represents the approximate current input to an electromagnetic coil actuator of a nominal system required to move such a member between positions in time optimal fashion.

대표청구항 ▼

A position control system for moving a member with time optimal motion between a current position and a target position in response to a single input command which defines the distance between said positions, comprising in combination: (a) an electromagnetic actuator coupled to said member and havin

A position control system for moving a member with time optimal motion between a current position and a target position in response to a single input command which defines the distance between said positions, comprising in combination: (a) an electromagnetic actuator coupled to said member and having a load acceleration characteristic which is proportional to the input current supplied thereto for accelerating and decelerating said member with said time optimal motion in response to an electric drive signal applied to the input circuit of said actuator; (b) means including a power source and a first summing junction connected to said actuator for providing to said actuator said drive signal to cause said member to tend to follow a predetermined acceleration and deceleration profile for said distance to be moved specified by said single input command; (c) a first generator for supplying to said first summing junction a first time varying signal corresponding to the profile of the actuator current required to move said member the distance specified by said input command with time optimal motion in an ideal system; (d) an error amplifier connected to supply an error signal to said first summing junction concurrently with said first time varying signal and having means for limiting the value of its output to no more than 15% of the value of said current drive signal; (e) a second order position control system in which position is the controlled variable and acceleration is the manipulated variable for providing to said error amplifier an error signal representing the difference in the instantaneous position of said member in said actual system and said ideal system, said error signal varying the instantaneous acceleration and deceleration of said member in a direction tending to reduce said instantaneous position error, and further including a position transducer connected thereto for providing a signal to said second order position control system corresponding to the instantaneous actual position of said member during said time optimal motion; and (f) means for controlling the operation of said first generator in response to the operation of said second order position control system to cause the respective signals generated thereby to be supplied concurrently to said first summing junction to achieve time optimal movement of said member.