Patent ID: 8225763

Claim:
A hydraulic actuator control device having a hydraulic actuator operated by supply and discharge of pressurized oil and a control valve that controls the supply and discharge of the pressurized oil to and from the hydraulic actuator, the hydraulic actuator control device controls the hydraulic actuator by outputting a control signal to the control valve, the hydraulic actuator control device comprising: a dead zone determining unit that determines a dead zone in which the hydraulic actuator does not respond to or shows reduced responsiveness to changes in the control signal; a holding value setting unit that sets a value of the control signal when an operating speed of the hydraulic actuator becomes zero as a holding value; a storing unit that stores, as model control characteristics, a changing tendency of responsiveness of the hydraulic actuator to the change in the control signal realized by a virtual model control valve; a correspondence coefficient calculating unit that calculates a correspondence coefficient, which is a ratio of a width of the dead zone to a width of a model dead zone of the model control characteristics, that is used as a coefficient for causing the control valve of the control device and the model control valve to correspond to each other; a model holding-value calculating unit that calculates a model holding value, which is the control signal value when the operating speed of the hydraulic actuator becomes zero in the model control characteristics, wherein the control signal value is calculated by using the correspondence coefficient to correct a deviation between a center value of the dead zone and the holding value; a model control-amount calculating unit that calculates a model control amount, which is a control amount whose reference is the model holding value, based on a deviation between an operating amount and a target operating amount of the hydraulic actuator; an in-dead-zone control amount calculating unit that calculates an in-dead-zone control amount of the control valve by using the correspondence coefficient to correct a model in-dead-zone control amount of the model control amount falling within the model dead zone; an out-of-dead-zone control amount calculating unit that calculates an out-of-dead-zone control amount of the control valve, based on a model out-of-dead-zone control amount of the model control amount that falls outside the model dead zone; and a control signal setting unit that sets a control signal that is output to the control valve, based on the holding value, the in-dead-zone control amount and the out-of-dead-zone control amount.