A device for the production of a tachometry signal of infinite resolution and without ripple from an inductive position sensor. The sensor is fed by a sinusoidal reference signal and supplies two phase signals. A resistance-capacitance circuit tuned to the frequency of the reference signal is fed by the two phase signals of the sensor and supplies a sinusoidal signal whose phase angle is proportional to the rotation of the sensor. This signal is then digitized and processed by digital phase comparators and low-pass filters before differentiation. This includes the use of particular digital phase comparators, each associated with a particular return to zero detector, to produce by a storage flip-flop and an electronic switch, the outgoing tachometry signal with the aid of a single differentiator with a device for elimination of discontinuities.
Jitter attenuators (100) with a phase detector (104) to control a crystal oscillator to remove jitter wherein the phase detector includes both a sequential phase/frequency detector (200) of low transistor count and an arrangement of two sequential phase/frequency detectors (198 and 200) to increase gain and two drivers for the crystal oscillator.
An auxiliary resolver position tracking (RPT) system for an industrial robot includes a resolver excitation and monitoring system which is powered by an uninterruptable power supply which includes a battery. The RPT system generates trapezoidal excitation pulses for the resolvers in the robot when no external excitation signal is applied, for example when the robot is shut down. Since there is relatively little motion to be detected in these instances, the RPT system switches between a slow position sampling rate, when no motion is detected, and a fast sampling rate when motion is detected. When operating on battery power, the RPT only switches to the fast sampling rate when motion is detected. To ensure that no motion data is lost when the system switches back to the slow sampling rate, the high sampling rate is maintained for a time sufficient to capture any residual motion of the robot. In addition, the RPT includes circuitry to detect when the external excitation signal is absent, to detect when individual invalid position samples may be taken and to distinguish between valid motion and a jitter condition in which the sensed resolver position oscillates between two quadrants.
An auxiliary resolver position tracking (RPT) system for an industrial robot includes a resolver excitation and monitoring system which is powered by an uninterruptable power supply which includes a battery. The RPT system generates trapezoidal excitation pulses for the resolvers in the robot when no external excitation signal is applied, for example when the robot is shut down. Since there is relatively little motion to be detected in these instances, the RPT system switches between a slow position sampling rate, when no motion is detected, and a fast sampling rate when motion is detected. When operating on battery power, the RPT only switches to the fast sampling rate when motion is detected. To ensure that no motion data is lost when the system switches back to the slow sampling rate, the high sampling rate is maintained for a time sufficient to capture any residual motion of the robot. In addition, the RPT includes circuitry to detect when the external excitation signal is absent, to detect when individual invalid position samples may be taken and to distinguish between valid motion and a jitter condition in which the sensed resolver position oscillates between two quadrants.
An auxiliary resolver position tracking (RPT) system for an industrial robot includes a resolver excitation and monitoring system which is powered by an uninterruptable power supply which includes a battery. The RPT system generates trapezoidal excitation pulses for the resolvers in the robot when no external excitation signal is applied, for example when the robot is shut down. Since there is relatively little motion to be detected in these instances, the RPT system switches between a slow position sampling rate, when no motion is detected, and a fast sampling rate when motion is detected. When operating on battery power, the RPT only switches to the fast sampling rate when motion is detected. To ensure that no motion data is lost when the system switches back to the slow sampling rate, the high sampling rate is maintained for a time sufficient to capture any residual motion of the robot. In addition, the RPT includes circuitry to detect when the external excitation signal is absent, to detect when individual invalid position samples may be taken and to distinguish between valid motion and a jitter condition in which the sensed resolver position oscillates between two quadrants.
An auxiliary resolver position tracking (RPT) system for an industrial robot includes a resolver excitation and monitoring system which is powered by an uninterruptable power supply which includes a battery. The RPT system generates trapezoidal excitation pulses for the resolvers in the robot when no external excitation signal is applied, for example when the robot is shut down. Since there is relatively little motion to be detected in these instances, the RPT system switches between a slow position sampling rate, when no motion is detected, and a fast sampling rate when motion is detected. When operating on battery power, the RPT only switches to the fast sampling rate when motion is detected. To ensure that no motion data is lost when the system switches back to the slow sampling rate, the high sampling rate is maintained for a time sufficient to capture any residual motion of the robot. In addition, the RPT includes circuitry to detect when the external excitation signal is absent, to detect when individual invalid position samples may be taken and to distinguish between valid motion and a jitter condition in which the sensed resolver position oscillates between two quadrants.
