Abstract: A motor control apparatus includes a sub-controller including a two-degree-of-freedom repetitive compensator and a shaping filter. The two-degree-of-freedom repetitive compensator includes a forward delay placed in a forward route of a loop and a feedback delay placed in a feedback route thereof and is configured so that a total delay time provided by the forward delay and the feedback delay is equal to the cycle of a target command or a disturbance. The shaping filter is configured so that the product of the pulse transfer function of the two-degree-of-freedom repetitive compensator and the complementary sensitivity function of a general-purpose control system has a low-pass characteristic.

Abstract: A motor controller, comprising a first simulation control unit (8) and a second simulation control unit (9) as a feed forward control means for inputting a command to an actual control unit (10) performing a feedback control, wherein the control parameter of the first simulation control unit (8) is set so that the high-speed property of a control response is increased, and the control parameter of the second simulation control unit (9) is set so that the stability of the control response is increased, whereby an entire feed forward control means can be designed so as to meet the requirements for the high-speed property and high stability of the control response.

Abstract: An impact tool control method and apparatus and an impact tool using the same. Pulses of torque applied to a fastener by the impact tool are measured. The duration and magnitude of the torque pulse are subtracted from a torque signal and the resulting difference is integrated over time to obtain a fastener angular velocity signal. The angular velocity signal is integrated over time to obtain a displacement signal which can be converted to a torque signal. The impact tool can be controlled based on the value of the torque signal.

Abstract: An amplifier for bidirectionally driving a motor includes circuitry for enabling the amplifier to operate with a bipolar input signal while employing a single power supply. The amplifier includes an input section which receives the bipolar input signal and provides a unipolar output voltage. The operational amplifier drives a bridge drive network to provide a drive current to output bridge transistor in one of two directions. The bridge network includes control circuitry for causing all of the transistors of the drive bridge to be operated in their active regions, thereby improving the power dissipation characteristics of the network. The output bridge transistors are also controlled to operate in their active regions. In addition, circuitry is included for providing negative feedback for the amplifier despite the fact that the output current is always a positive current.

Abstract: A servo-system includes a high-gain direct-coupled direct current (dc) differential amplifier to which a dc input signal is fed. An adder adds the dc amplifier output to a comparison voltage, and the adder output is applied through a filter circuit to a second input of the differential dc amplifier. A servo-amplifier drives a servo-motor in accordance with the dc amplifier output. Means are provided for zero-balancing the dc amplifier output while varying the comparison voltage by the servo-motor.

Abstract: A servo-system is provided for self-balancing systems using an ac servomotor capable of maintaining loop gain substantially constant irrespective of span adjustment and without capacitor coupling. It includes a direct-coupling dc amplifier for comparing input and comparison signals and amplifying the result, a servo amplifier having a differential direct-coupling amplifier with inverting and non-inverting input terminals, with feedback from its output to the inverting input terminal and a switch to the non-inverting input terminal operating at the same frequency as the ac power source for the servomotor, to maintain the loop gain constant irrespective of span adjustment, and means causing the ac servomotor to move a slide resistor to bring the compared signal into balance with the input signal.Provision is also made for receiving input signals from thermoelectric or resistance thermometers and balancing the system using these signals.

Abstract: A process controller for diameter control in drawing optical fibre preforms consists essentially of the parallel arrangement of two output amplifiers, one providing low gain at low .+-. input voltages, while the other has high gain at high .+-. input voltages and effectively zero gain at low .+-. input voltages.