Abstract: An electrohydraulic servo control system responsive to a load acceleration or velocity command input signal wherein the input command signal is integrated and compared with position feedback from the valve actuator and load to obtain an error signal which controls the actuator. The velocity command input may be multiplied by an exponential factor to compensate for system following error. Another modification contemplates resetting of command signals to compensate for following error and to eliminate dead time upon change of direction of the load by the operator.

Abstract: An improved apparatus and process for sensing a test object by means of a switching sensor which is movable relative to the test object, in which the relative position between the test object and the switching sensor is measured by a measuring instrument. The switching sensor generates a switching signal at the moment of contact with the test object in order to cause the instantaneously prevailing measuring value of the measuring instrument to be retained. Such measuring values commonly are characterized by sensing errors as a function of the sensing speed and/or the material pairing between the switching sensor and the test object.

Abstract: A servomotor controller provides high speed servomotor positioning be means of an on line adaptive state-feedback control algorithm. Servomotor position and velocity are the feedback states and each has an associated gain selected by means of a servomotor characterization scheme. The mechanical break frequency is used to select optimum gains and a high speed estimation technique is used to determine the mechanical break frequency. Position step change may also be used to select optimum gains. Gain tables are produced by an off-line simulation technique.

Abstract: A slot detecting apparatus comprises a sensor for detecting a slot of a workpiece, comparators, and a discriminating circuit. The sensor moves over the workpiece so as to traverse the slot and produce an output having a waveform which is substantially an M-shape. The comparators compare the level of the output of the sensor with a plurality of threshold levels which are mutually different, and each produce a comparison result for each of the plurality of threshold levels. The discriminating circuit discriminates the position of the slot based on a comparison result which indicates that the output of the sensor has a waveform which is substantially an M-shape, from among a plurality of comparison results which are obtained from the comparators for the plurality of threshold levels.

Abstract: A sensor is provided in a hospital bed having a bed-mat made of movable particles. This sensor is to detect an excessive bead temperature in the case of a controller malfunction and to control the operation of a cooler. In the sensor, the circuit is so designed that an air compressor runs intermittently with the aid of timers while the sensor performs its functions at a temperature above the predetermined temperature level. The sensor also enables the compressor to run again when the temperature of the mat lowers to a level where a normal operation is possible to assure temperature control of the bed-mat even in the case of controller malfunctions.

Abstract: In a control apparatus for a multi-jointed arm mechanism having a plurality of arm elements in order to enhance the operating speed of each arm element, a true control error between a fore end of the arm element and a target position therefor, resulting from a movement of the arm element, and a predicted control error thereof have their difference evaluated, and the arm element is controlled so as to make the difference zero.

Abstract: X-Y position measurement apparatus is employed with feedback controlled X-Y positioning apparatus for positioning a workpiece stage at a desired X-Y coordinate position in response to signals indicative of the actual position and the desired position of the workpiece stage. A normalization circuit is employed for gain correction of the signals indicative of the actual position of the workpiece stage.

Abstract: In a numerical control system, a machine tool with an automatic tool changer is provided with an origin detector for generating an origin signal when an NC drive axis for effecting relative movement between a spindle head and a work table in an axial direction of a tool spindle is returned to a machine origin. A numerical controller is connected to the NC dirve axis, the tool changer and when operated in accordance with a numerical control program, controls them so that a series of machinings can be selectively performed on a workpiece on the work table. The numerical controller executes an emergency returning control program when a manual switch is depressed to instruct the returning of the NC drive axis to the machine origin.

Abstract: A control system for driving a variable speed AC motor employing a fixed frequency AC power source, combines pulses representative of a desired slip frequency with pulses of a frequency proportional to the speed of the motor. The combined pulses are employed with a speed command signal to set a threshold which determines the fraction of each cycle of the AC primary power which is fed to the motor. In addition, the speed and slip pulses are employed to direct the AC power to specific ones of the windings of the motor to thereby create a rotating magnetic field in the induction motor. An array of silicon-controlled rectifiers does the actual gating and an SCR protect circuit ensures that transfer of control from one SCR to another is inhibited until all current ceases to flow in an SCR being extinguished. A forced commutation circuit forces the extinction of all current remaining in the last conducting SCR feeding a motor winding at the transfer time from that motor winding to the next.

Abstract: An open loop controller for the stepper motor of a disk drive actuator is programmed to supply pulse width modulated drive voltages for energizing and de-energizing successive phases of the stepper motor at controlled rates during the initial and final phases of each actuator seek, thereby controlling the acceleration and deceleration profiles of the actuator to reduce its mid-frequency resonance, settling time and position hysterysis.

Abstract: A method and a device for inputting the coordinates of a robot acts so that the coordinates are input accurately by scanning the working area of the robot and inputting, as coordinates of the working position, positional data when a sensor has detected the working position. A movement data calculator (138) receives target position data from a preteaching data area (146), operates a pulse register (130) and drive circuits (152), (154), (156), and makes the sensor positional data in a position register (130) coincide with the target positional data. It then receives positional vector data from a plane scanning data area (148) and a vertical scanning data area (150) and scans the sensor over the working area.

Abstract: A system and method are disclosed for precisely positioning a movable member to a desired fine position after a selected coarse position is reached. In a preferred embodiment of the invention a processor-controlled typewheel servo control system is responsive to a command signal for a selected coarse position for selectively utilizing from a memory circuit preselected stored adjustment information for the selected coarse position comprised of an associated coarse position count and quadrant information related to the sinusoids generated by an optical encoder in order to make a precise fine position adjustment in the position of a typewheel after the selected coarse position is reached for that typewheel.

Abstract: Described herein is a steering amplifier for use in the steering systems of watercraft. Potentiometers are mounted within the helm unit and the feedback unit of the craft and these potentiometers are used to determine the various helm and rudder positions. Circuitry is provided to determine the difference or error between the helm position and the rudder position and to energize solenoid valves which cause the rudder to move in the appropriate direction to correct the error.

Abstract: The capability of compensating automatically for a failure in an actuator and the associated drive circuit is enhanced by providing a dual channel actuator, each channel having a drive coil and a position sensor tracking the position of the actuator output shaft. A separate circuit is provided for each actuator channel to detect drive loop failures and hydraulic failures. When the drive loop of one channel fails, it is disengaged, and the gain in the remaining drive loop is doubled to maintain authority. In an embodiment, the remaining drive loop cannot disengage when certain criteria, relating to the failure of associated actuators, are met. The invention is particularly useful for aerospace applications.

Abstract: A speed monitoring circuit is disclosed for an automatic positioning system. This speed monitoring circuit composes a measurement of the actually present speed determined from measurement signals generated by an incremental position measuring device with the desired speed commanded by the positioning system. The difference between the actual and commanded speed is detected and, in the event of an excessive deviation, a warning or an automatic termination of operation of the positioning system is provided. In the disclosed system, the desired speed is determined by a controller in which a digital computer calculates the difference between the instantaneous position of one relatively movable machine component and the desired position of the movable component as established by programmed data.

Abstract: An adjustable servo-system for controlling the operating condition of its servo-motor adjustably includes an indicator unit capable of indicating a new optimum operating time to be used. The operator can set the new optimum operating time in the servo-system just by looking at the indicator.

Abstract: In order to permit manual operation under a condition where the axial direction of a tool and the direction of a hole to be machined in a workpiece are held in agreement, the tool of a radius .gamma. is rotated by .theta. in the vertical rotational direction and by .rho. in the horizontal rotational direction in a orthogonal coordinate system and in a spherical coordinate system the origins of which coincide with the center of rotation of the tool. Upon doing so, in the orthogonal coordinates, the position of the front end of the tool becomes X.sub.0 =.gamma. sin .theta..multidot.cos .rho., Y.sub.0 =.gamma. sin .theta..multidot.sin .rho. and Z.sub.0 =.gamma. cos .theta.. Therefore, a train of pulses (Hp) from a manual pulse generator are distributed as X-, Y- and Z-axial components in the proportion to the above values by a manual pulse distribution circuit, and motors for the respective axes are driven through servo circuits by the pulses.

Abstract: A multiplex control system including a plurality of controllers, the main controller being arranged by hardware, while the subsidiary controller being accomplished by software. Each of the controllers has a PID operator for calculating the proportional, differential and integral components of process data, and the difference of the integral components of both PID operators is processed through a first-order time lag operator and the result is used to correct the error of the output from the PID operator of the subsidiary controller. In the occurrence of abnormality, control of the control object is switched from the main controller to the subsidiary controller using the first-order time lag element attached to the switch unit thereby preventing the tracking of control data.

Abstract: An electric servo system has an electrical drive and a controllable object driven by the electrical drive whereby an error between an actual amount of actuation of the controllable object and a target value toward which the object is controlled is applied to the electrical drive to control the same so that the amount of actuation of the controllable object coincides with the target value. A compensator is provided on the input side of the electrical drive, for compensating the load characteristics of the controllable object such that the output of the electrical drive does not have apparent dependency on torque of the load.

Abstract: A two axis joystick controller (14) produces at least one output signal in relation to pivotal displacement of a member (32) with respect to an intersection of the two axes. The member (32) is pivotally movable on a support (42) with respect to the two axes. The support (42) has a centrally disposed aperture (46). A light source (34) is mounted on the pivotally movable member (32) above the aperture (46) to direct light (47) through the aperture. A light sensor (48) is mounted below the aperture (46) in the support (42) at the intersection of the two axes to receive the light (47) from the light source (34) directed through the aperture (46). The light sensor (48) produces at least one output signal related to a location on the sensor (48) at which the light (47) from the light source strikes the sensor (48). The two axis controller (14) is small enough in size to be mounted on another, hand-operated X-Y controller (10) for thumb operation by a hand positioned to operate the other X-Y controller (10).