Linear motor acceleration control system

Claim 1

A vehicle displacement control system for effecting controlled vehicular travel between two points according to a program of velocities and velocity changes, comprising: a vehicle adapted for displacement along the prescribed route which passes through said point five; at least one controllable propulsion source for said vehicle; first computer means for determining the position of said vehicle between said points and for producing a position signal; means for producing a jerk limit signal; means including an integrator having an input connected to receive said jerk limit signal for producing an acceleration control such that velocity changes are made within a jerk limit; means operatively interconnected with said first computer means for producing command vehicle velocity signals at various positions along said route; means for producing actual vehicle velocity signals; means for producing a vehicle velocity error signal representing the difference between actual vehicle velocity and command vehicle velocity; second computer means connected to receive said command vehicle velocity signal and said actual vehicle velocity signal for producing a jerk control signal whenever the actual vehicle velocity is at least equal to the command vehicle velocity less a predetermined vehicle velocity increment related to said jerk limit; and mode select switch means operating under the control of said jerk control signal for selectively connecting one of said acceleration control signals, said position signal, and said vehicle velocity error signal to said controllable propulsion source for regulating the thrust thereof to produce vehicle velocity changes at predetermined times and positions, but only at such rates as are permitted by said jerk limit signal, whereby said control system operates discretely in either a position-controlled servo loop mode, a velocity-controlled servo loop mode, or an acceleration-controlled servo loop mode, depending upon said program and the condition of said mode select switch.