Disclosed herein is a motor driver circuit including a logic circuit that generates a second code which changes linearly with a slope “a” with respect to a first code based on a position command for a linear motor to be driven and that can switch the slope “a,” a D/A converter that converts the second code into an analog control signal, and a driver that drives the linear motor such that a current detection signal indicating a drive current of the linear motor approaches a target value that changes linearly with a slope “g” with respect to the control signal, the driver being configured to switch the slope “g.” The motor driver circuit is switchable between a first state in which g=g.sub.1 and a=a.sub.1 and a second state in which g=g.sub.2 (where |g.sub.2|>|g.sub.1|) and a=a.sub.2=a.sub.1×(g.sub.1/g.sub.2).

Disclosed herein is a motor driver circuit including a logic circuit that generates a second code which changes linearly with a slope “a” with respect to a first code based on a position command for a linear motor to be driven and that can switch the slope “a,” a D/A converter that converts the second code into an analog control signal, and a driver that drives the linear motor such that a current detection signal indicating a drive current of the linear motor approaches a target value that changes linearly with a slope “g” with respect to the control signal, the driver being configured to switch the slope “g.” The motor driver circuit is switchable between a first state in which g=g.sub.1 and a=a.sub.1 and a second state in which g=g.sub.2 (where |g.sub.2|>|g.sub.1|) and a=a.sub.2=a.sub.1×(g.sub.1/g.sub.2).

A motor driver circuit includes: an error detection amplifier configured to receive a current feedback signal indicating a drive current of a motor as an object to be driven and an analog command signal indicating a target amount of the drive current, and generate an analog error signal indicating an error between the drive current and the target amount of the drive current; an A/D converter configured to convert the analog error signal generated by the error detection amplifier into a digital error signal; a digital compensator configured to generate a digital control amount based on the digital error signal output by the A/D converter; a D/A converter configured to convert the digital control amount into an analog control signal; and an output stage configured to supply a drive signal according to the analog control signal to the motor.

A motor driver circuit includes: an error detection amplifier configured to receive a current feedback signal indicating a drive current of a motor as an object to be driven and an analog command signal indicating a target amount of the drive current, and generate an analog error signal indicating an error between the drive current and the target amount of the drive current; an A/D converter configured to convert the analog error signal generated by the error detection amplifier into a digital error signal; a digital compensator configured to generate a digital control amount based on the digital error signal output by the A/D converter; a D/A converter configured to convert the digital control amount into an analog control signal; and an output stage configured to supply a drive signal according to the analog control signal to the motor.

A prismatic actuator for imparting a hopping motion to a supported load such as a leg of robot. The apparatus includes a direct drive motor, such as a voice coil, operable to provide translational motion. The apparatus includes a spring element and a prismatic guide assembly. The guide assembly is configured to support the direct drive motor to constrain the translational motion to be along a drive axis and support the spring element to constrain compression and expansion of the spring element along a longitudinal axis parallel to the drive axis. The apparatus includes a controller that: (1) first controls the direct drive motor to compress the spring element during a first time period beginning when the apparatus initially contacts a surface; and (2) second controls the direct drive motor to expand the spring element when the apparatus has zero velocity while contacting the surface.

A prismatic actuator for imparting a hopping motion to a supported load such as a leg of robot. The apparatus includes a direct drive motor, such as a voice coil, operable to provide translational motion. The apparatus includes a spring element and a prismatic guide assembly. The guide assembly is configured to support the direct drive motor to constrain the translational motion to be along a drive axis and support the spring element to constrain compression and expansion of the spring element along a longitudinal axis parallel to the drive axis. The apparatus includes a controller that: (1) first controls the direct drive motor to compress the spring element during a first time period beginning when the apparatus initially contacts a surface; and (2) second controls the direct drive motor to expand the spring element when the apparatus has zero velocity while contacting the surface.

A drive circuit, which is mounted on an electronic apparatus having a voice coil motor and drives the voice coil motor, includes: an interface circuit configured to receive a first signal indicating a target position of the voice coil motor and a second signal related to a posture of the electronic apparatus; a control circuit configured to generate a current command value of a drive current in response to the first signal and the second signal; and a current driver configured to generate the drive current in response to the current command value and supply the drive current to the voice coil motor.

A drive circuit, which is mounted on an electronic apparatus having a voice coil motor and drives the voice coil motor, includes: an interface circuit configured to receive a first signal indicating a target position of the voice coil motor and a second signal related to a posture of the electronic apparatus; a control circuit configured to generate a current command value of a drive current in response to the first signal and the second signal; and a current driver configured to generate the drive current in response to the current command value and supply the drive current to the voice coil motor.

Robotic drummers include voice coil actuators that are coupled to linear-to-rotary motion convertors to produce drumstick rotations so as to strike a drum head. Such rotations can be triggered via a microprocessor using stored performance data, by a user with a mouse, trackpad, joystick, or other user input device. Performances are enhanced by driving the VCA with drive signals have random variations associated with strike timing, amplitude, location, and speed. Multiple strikes are provided by reducing, eliminating, or reversing drumstick rotation with a corresponding drive signal upon detection of drumstick contact with the drum head.

Robotic drummers include voice coil actuators that are coupled to linear-to-rotary motion convertors to produce drumstick rotations so as to strike a drum head. Such rotations can be triggered via a microprocessor using stored performance data, by a user with a mouse, trackpad, joystick, or other user input device. Performances are enhanced by driving the VCA with drive signals have random variations associated with strike timing, amplitude, location, and speed. Multiple strikes are provided by reducing, eliminating, or reversing drumstick rotation with a corresponding drive signal upon detection of drumstick contact with the drum head.