Abstract: A voice coil actuator having a capacitive sensor. A magnetic housing contains at least one magnet, and has a wall that defines a first cavity. A magnetic core is coupled to the magnetic housing and extend from an interior surface of the magnetic housing in a direction of a center axis of the wall of the magnetic housing. A coil assembly has a wall defining a second cavity that at least partly envelops the magnetic core, disposed at least partly inside the first cavity, and adapted to move linearly with respect to the magnetic housing. The coil assembly forms a capacitive sensor with the magnetic core, the capacitive sensor adapted to measure at least one of position, velocity and acceleration of the coil assembly with respect to the magnetic housing.

Abstract: A digital incremental encoder for generating an output signal indicative of an angular position, a direction of rotation, and a speed of rotation of a shaft. A counter receives a PWM signal indicative of the angular position of the shaft and a clock signal from an angular position sensor, and generates a multi-bit output. A latch latches the multi-bit output, a first bit and a second bit of which are used to generate the output signals that include the first bit. The first bit and the second bit may be XOR'd together to generate an XOR output included in the output signals. A direction of rotation may be derived from a quadrature phase relationship between the first bit and the XOR output. The angular position sensor may be an NCAPS or MT-NCAPS. A linear position sensor may be used instead of an angular position sensor to generate the PWM signal.

Abstract: A multi-turn pulse width modulation (PWM) generator for generating a PWM output corresponding to multiple 360 degree turns. A counter receives a reference signal, and counts a number of cycles of the reference signal to generate a binary output corresponding to the number of cycles counted. A frequency divider receives a sensor output signal, and divides the frequency of the sensor output signal by the number of turns in the multiple turns to generate a frequency divided signal. The sensor output signal has substantially the same frequency as the reference signal, but can be offset in phase from the reference signal. A demultiplexer receives the binary output, and generates a plurality of turn indicator signals, each corresponding to one of the multiple turns. A multiplexer receives the turn indicator signals and a mechanical turn indication signal, and selects one of the turn indicator signals that corresponds to the mechanical turn indication signal.

Abstract: A radial movement capacitive torque sensor includes a pair of concentric capacitor plate rings lying in a common plane, a capacitor plate ring facing the pair of concentric capacitor plate rings, and a paddle assembly disposed between the pair of concentric capacitor plate rings and the capacitor plate ring. The paddle assembly includes a first rotor having a circular opening and having at least one pair of spaced apart bearings mounted thereon, a second rotor having a circular opening and having at least one pivot point located thereon, and at least one paddle having a dielectric head, a curved neck and a body. The curved neck is disposed between a corresponding one of said at least one pair of spaced bearings, and the body is pivotally coupled to a corresponding one of said at least one pivot point.

Abstract: A differential capacitive torque sensor for a continuously rotating shaft such as the steering column of an automobile provides an apertured metal cage shielding a dielectric rotor. They are respectively mounted on opposite sides of a split shaft connected by a torsion bar. The relative rotation of the apertured conductive plates and the rotor change the overall differential capacitance of the system to proportionally indicate clockwise or counter-clockwise torque.

Abstract: A vertical movement capacitive torque sensor for a rotating shaft such as the steering column of an automobile includes dielectric vanes interposed between capacitor plates which are moveable proportional to the angular displacement of two shaft portions which are linked by a torsion bar or concentric inner and outer shaft portions, the vanes move in a radial direction perpendicular to the shaft axis. Concentric capacitor rings are provided so that a bridge circuit can easily indicate differential capacitance which is proportional to clockwise or counter-clockwise torque.

Abstract: A digitally programmable pulse-width-modulation (PWM) converter changes a 0% to 100% duty cycle input signal to any desired start and stop duty cycle range; for example, 5% to 95%. This is achieved by the difference in start and stop duty cycles forming a ratio which determines a pair of clock frequencies for modifying the PWM signal to provide the new start and stop duty cycle parameters.

Abstract: A non contacting angular differential displacement torque sensor utilizes a split shaft with a connecting torsion bar with a pair of receive disks each with an intervening coupler disk carrying a conductive attenuating pattern where the inductive coupling between transmit and receive disks is individually attenuated in accordance with the angular position of the shaft on which the disks are mounted. The pair of receive disks which receive signals from a common transmitter have their angular difference taken and this is the actual torque on the shaft.

Abstract: A vertical movement capacitive torque sensor for a rotating shaft such as the steering column of an automobile includes dielectric vanes interposed between capacitor plates which are moveable proportional to the angular displacement of two shaft portions which are linked by a torsion bar or concentric inner and outer shaft portions, the vanes move in a radial direction perpendicular to the shaft axis. Concentric capacitor rings are provided so that a bridge circuit can easily indicate differential capacitance which is proportional to clockwise or counter-clockwise torque.

Abstract: A non-contact linear position center has juxtaposed transmit and receive sections with a coupler or slider section interposed therebetween carrying a symmetrical attenuating conductive pattern. The inductive coupling of coils on the transmitter and receive sections is attenuated in accordance with the linear position of the pattern on the coupler. A unique sinusoidal signal is generated whose phase is indicative of the linear position of the coupler.

Abstract: A non contacting angular differential displacement torque sensor utilizes a split shaft with a connecting torsion bar with a pair of receive disks each with an intervening coupler disk carrying a conductive attenuating pattern where the inductive coupling between transmit and receive disks is individually attenuated in accordance with the angular position of the shaft on which the disks are mounted. The pair of receive disks which receive signals from a common transmitter have their angular difference taken and this is the actual torque on the shaft.

Abstract: A non-contact angular position sensor has juxtaposed transmit and receive disks with a coupler disk, carrying a conductive attenuating pattern interposed therebetween. A pattern of inductive coils, which completely encircle both the transmit and receive disks have their inductive coupling individually attenuated in accordance with the angular position of the symmetrical conductive pattern on the intermediate coupling disk. The transmit disk is driven by a signal source which when received and demodulated by the receive coils and summed together provides a unique sinusoidal signal whose phase is indicative of the angular position of the intermediate coupler. The conductive pattern on the coupler is designed to provide a linear output.

Abstract: A non-contact linear position center has juxtaposed transmit and receive sections with a coupler or slider section interposed therebetween carrying a symmetrical attenuating conductive pattern. The inductive coupling of coils on the transmitter and receive sections is attenuated in accordance with the linear position of the pattern on the coupler. A unique sinusoidal signal is generated whose phase is indicative of the linear position of the coupler.

Abstract: A high efficiency fuzzy logic based Stirling cycle cryogenic cooler has increased efficiency by driving the system in the demand mode (near the desired set point cooling temperature) by a more efficient sinusoidal waveform. The compressor pistons of the Stirling compressor are driven by a voice coil actuator between compressing the coolant gas and then releasing and being driven against an opposing return spring. Since a square wave provides faster cool-down, this is utilized during that mode. In addition, to utilize the rebound effect of both the ambient gas pressure and the return springs, the voice coil actuator drive is turned off during one-quarter cycle rebound portions of the cooling cycle.