Abstract:
A servomotor control method utilizing conventional linear control techniques, which permits easy introduction of sliding mode control. The phase surface of the sliding mode is made to be equivalent to a mode of obtaining a torque command by a conventional linear control, and a switching input (.tau.1) is added to the torque command (.tau.0) obtained by the linear control, thereby further obtaining a corrected torque command (.tau.). The switching input (.tau.1) is determined in accordance with the positive or negative sign of the torque command (.tau.0) and the signs of various values such as a position deviation (.epsilon.), a speed loop integral, etc., which are obtained during the calculation of the torque command (.tau.0).
Abstract:
A sliding mode including a process of feeding back an amount of twist for controlling a servo loop is controlled by reading the position of a servomotor and the position of a mechanical actuator drivable by the servomotor (SP1), calculating an amount of twist which is an error (SP2), calculating a switching surface Suf with a value produced by filtering the amount of twist (SP3), and selecting a switching input with the produced value (SP4, SP5, SP6). The amount of twist is filtered by a filter which has a numerator and a denominator which are of a first order. The filter allows a system to be realized which suffers less vibration and is robust against inertia fluctuations.
Abstract:
A robot control method based on an acceleration/deceleration time constant wherein the acceleration/deceleration time constant of a servomotor is set for an optimum value for each block, to thereby control the operation of the robot. A reaching speed (Vu) is determined from an amount of movement (X) of a block, and based on the reaching speed, a maximum torque (Tmax) of the servomotor is determined and then a static load torque (T.sub.wn) is subtracted from the maximum torque (Tmax) to determine an acceleration torque (Ta.sub.n). Thereafter, based on the acceleration torque (Ta.sub.n) and the load inertia of the servomotor, an acceleration (a.sub.n) is determined and an acceleration/deceleration time constant (.tau.) is determined from the acceleration (a.sub.n), and accordingly, an optimum acceleration/deceleration time constant is determined.
Abstract:
A sliding mode control method with a feedforward compensation function achieves a control response characteristic adapted to varying system parameters and properly maintains a manipulated variable affecting a controlled object. A position deviation (.epsilon.), speed deviation (.epsilon.), predicted maximum and minimum inertias (Jmax, J0), predicted maximum and minimum gravity loads (GRmax, GRmin), switching variable (s), integral element (.intg.(.epsilon.+C.multidot..epsilon.)), second differential (.theta.r) of the command position, and actual speed (.theta.) are periodically calculated on the basis of a command position (.theta.r), actual position (.theta.), inertia data, and gravity load data (100-102, 104, 107, 110, 114, 117, 120, 123, 127). Even when a nonlinear system parameter such as inertia varies, a proper torque command (T) is periodically calculated, as a manipulated variable, on the basis of a switching amount (T1) obtained by adding together five terms calculated in accordance with respective positive or negative signs of the switching variable, position deviation, integral element, second differential, and actual speed (105, 106, 108, 109, 111-113, 115, 116, 118, 119, 121, 122, 124 to 126, 128-131).