Abstract: A servomotor velocity control system according to the present invention control velocity by using an observer for obtaining a sensed value of velocity while estimating motor load torque. When resolution of a rotary encoder is a problem in a region of low motor velocities, this is compensated for to improve the velocity sensing precision in the low-velocity region. In a region of high motor velocities, velocity processing is executed based on the output of the rotary encoder considering the processing time of a CPU. Use or non-use of the observer for obtaining the estimated value of velocity is selected in dependence upon the velocity of the motor.

Abstract: Servoed accelerometer with isolated voltage torquing having first and second grounds, a servoed accelerometer having a torque coil, and an amplifier for driving said torque coil. The amplifier has inverting and non-inverting junctions. The second ground is coupled to the non-inverting junction of the amplifier. A torque signal supply is coupled to the first ground. A transformer is provided for coupling the torque signal supply to the non-inverting junction of the amplifier and serves to isolate the torque signal supply from the non-inverting input of the amplifier so that the amplifier and polarity of the torque signal are preserved.

Abstract: In a speed correcting device for use in a speed command system such as a numerical controller or a tracer controller in which a movable machine part is driven at a speed corresponding to a speed command value, an error in the moving speed of the movable machine part is removed by detecting the moving speed corresponding to the speed command value being zero and by adding to the speed command value a moving speed correction amount that cancels the detected moving speed.

Abstract: In an acceleration/deceleration control system of a servo motor, an acceleration/deceleration control section (5) has a low-pass filter (4) of second or higher order when an exponential acceleration/deceleration system is used, and the acceleration/deceleration section (5) has a linear acceleration/deceleration section (3) and the low-pass filter (4) of second or higher order connected to the output of the linear acceleration/deceleration section (3) when a linear acceleration/deceleration system is used. A position instruction (Pa) is filtered through the low-pass filter (4) of second or higher order, and a filtered signal is supplied to a servo control section (6), thereby driving the servo motor (M).

Abstract: A servomotor speed control system includes a ROM table which stores a minimum distance suited for each motor speed. When the minimum distance corresponding to the current motor speed becomes shorter than the current distance from the current motor position to a positioning target point, the instructed speed is reduced to decelerate the servomotor rotation. In a preferred form, the unit of the distance is identical with an interval of a position indicating signal developed from a rotary encoder associated with the servomotor.

Abstract: A device for driving a motor-operated closure part for an opening, especially on a motor vehicle, having a protective circuit for interrupting the closing movement when there is an indication that an object may be obstructing closure of the opening. A speed transmitting means exists that detects the adjusting speed of the closing part on at least one range of the adjusting path of the closure part that is critical with respect to the engagement of an obstruction. In addition, an evaluating stage is provided that responds to the speed signal and/or its rate of change with respect to time, for producing an obstruction signal that activates a control means of the circuit to interrupt the closing movement.

Abstract: The motor control system for an electric motor having no mechanical means integral therewith for commutating current provides the ability to control position, velocity and torque of such a motor to the degree achievable with DC motors having mechanical commutators. Such a result is achieved by maintaining a desired spatial relationship between the resultant magnetic field created by the stationary member and the movable member of the electric motor. The control system includes detecting apparatus for detecting parameters of the motor that dictate, in part, the desired spatial relationship within the motor and command apparatus for creating a motor command signal which, when generated in the motor, causes the desired spatial relationship to be established. The present invention also permits maintenance of an optimal spatial relation--a spatial relationship that causes the motor to produce desired torque with a minimum excitation.

Abstract: A position control system of closed-loop configuration in which a position detector is provided on a motor-driven machine element for sensing the position thereof and a rotary encoder is provided on the motor shaft for detecting the rotational speed thereof by producing pulses of a frequency proportional to the rotational speed. The system includes a device for controlling position based on a position detection signal from the position detector and a motor position signal from the rotary encoder, and a device for controlling speed based on a rotational speed signal from the rotary encoder and an output from the position control device.

Abstract: Each of some automatic machines, such as an industrial robot of the type having a servo-amplifier (4) controlled by a central processing unit (1) through a servo-control (3), has a plurality of control modes for moving a movable part (50), for example, teaching and playback modes. In the specified control mode, for example, the teaching mode, the velocity or driving force of the movable part (50) is restrained directly via a man-machine interface (7) by controlling either or both of the servo-amplifier (4) and a power source (5) to regulate driving energy supplied by a servo-motor (8) to the movable part (50) so as to mitigate danger to a person who is near the movable part.

Abstract: An improved control apparatus and method for servo system control is disclosed wherein a generally increasing or decreasing control signal is supplied to a source of energy when a desired parameter of interest produced by said source of energy is not equal to a desired value, and a constant control signal when the parameter of interest does equal the desired value. The constant control signal is determined by the previous constant control signal plus the product of the difference between the peak value of the generally increasing or decreasing control signal and the previous constant control signal multiplied by a constant.

Abstract: An apparatus and method for position control by a DC servomotor having improved stiffness. An electric current (i.sub.R) of the servomotor is interpreted anew and defined as follows: ##EQU1## where .theta. is an observed rotation angle of the load (L), .theta..sub.c is a precommanded value, K.sub.F is a feedback coefficient, and K.sub.V is a velocity coefficient. After normalizing the above equation, stiffness (S) can be increased by incorporating a limiter into the control system, thus providing prompt response and smooth covergence of .theta. to .theta..sub.c with a high degree of stiffness maintained at the precommanded angle (.theta..sub.c).

Abstract: A motor compensation network for use with a two-degree of freedom velocity servo controller includes first and second compensation means. The first compensation means receives a signal representing a difference between a velocity command signal and a velocity feedback signal and provides a modified output signal. The second compensation means receives the velocity feedback signal and provides a modified output signal. Bandwidth adjustment means are coupled to the first and second compensation means. Damping factor adjustment means are coupled to the second compensation means. The transfer function of the first compensation means has characteristics of an integrator. The transfer function of the second compensation means has a first and a second component. The first component has characteristics of a differentiator, while the second component has characteristics of a proportionality or a gain constant.

Abstract: A method of adaptive control for use in a controlled system having an adjustable forward loop gain and a control system apparatus for carrying out the method are disclosed. The control system measures the value of a parameter which is to be controlled and generates an error signal by comparing the measured valve of the parameter with a desired valve. The error signal is squared and the time derivative of the squared error signal is obtained. The control system compares the length of time that the derivative so obtained has a positive value to the time it has a negative value to obtain a gain control signal, and applies the gain control signal to the forward loop gain. The gain control signal reduces the adjustable forward loop gain until a preselected margin of stability in the controlled system is obtained.

Abstract: A closed loop servo operated digital control system in which a dynamically operable moveable member can be effectively and accurately controlled during movement from an initial position to a command position by compensating for both velocity error and for position error. A differential between a present measured position of the moveable member and a command position provides a position error signal. Present velocity is determined by computing position differential as a function of time. A velocity error signal is obtained by subtracting the determined velocity from a velocity command which is stored as a velocity command profile. The total error is the resultant sum of the position error and a velocity error and this sum is converted to an analog signal in order to power an amplifier/motor which, in turn, provides power for the control system.

Abstract: Real time servo control in a nonlinear, cyclical dynamic system adjusts the energy applied to a prime mover from a source of the energy as a linear function of an error between the measured load characteristics and modeled load characteristics. The modeled load characteristics are linearized as a function of the initial conditions of the load at the beginning of each cycle.

Abstract: Apparatus for controlling the angular velocity of a motor shaft comprising a memory for storing digital data equivalent to a desired angular velocity curve for the motor shaft, means for determining the actual angular velocity of the shaft, means coupled to the memory and the means for determining the actual angular velocity of the shaft for comparing the actual angular velocity of the shaft with the desired angular velocity according to said curve and a computer coupled to the comparing means and the motor for adjusting the current to the motor whereby the velocity thereof is adjusted according to the comparison to cause said motor to have a velocity corresponding to said curve.

Abstract: An improved electronic control system employs a primary servomechanism loop which includes an error signalling difference node and a stability compensating forward gain/drive element intermediate an input command signal source and a controlled output element. A second, similar image feed back loop is operative upon a simulated representation of the controlled output element or plant, and is exercised by the input command source. The error node in the second image loop generates a loop error signal responsive to the difference between the input command and the simulated, predicted response for the controlled element.In accordance with the present invention, the two error signals produced by the actual and image feed back loops are compared and generate a supplementary feed back signal which is summed with the plant-driving signal applied to the controlled element.

Abstract: Electronic compensation apparatus for a drive system associated with a torque motor of an electrohydraulic servovalve. The apparatus includes means to define an open loop transfer function characteristic of the drive system, wherein the transfer function corresponds to a notch filter. Further included are means to provide the open loop characteristic with a closure rate of approximately no more than 6 db/octave with respect to a function 1/.beta.=1-G.sub.cl (s), where G.sub.cl (s) corresponds to a closed loop transfer function of the drive system. In particular, the notch filter may be realized in a drive system that includes a series resistive-capacitive circuit connected in parallel with the torque motor. The 6 db/octave closure rate is provided by a variation of the impedance of the series resistive-capacitive circuit.

Abstract: An auxiliary channel coupled to a selected loop in a plurality of process control loops included in a direct digital control system, the channel serving to expand the frequency response of the selected loop. The system is provided with a digital computer acting as an electronic controller common to all loops, each loop including a transducer sensing a particular process variable to produce a corresponding analog input signal which is digitized and compared in the computer with a set point signal to yield, after conversion, an analog output signal for operating a final control element in the loop to correct for process variations. The analog input signals from the respective loops are sequentially fed into the computer through a multiplexer at a relatively slow sampling rate whereby the loops are normally responsive only to the low-frequency component in the sampled process variables representing slow changes.

Abstract: The disclosure describes a digital servo control circuit to actuate an analog servo motor smoothly from an actual present position to a new desired servo position in response to digital information from a computer. The control circuit described receives from a computer digital information representative of a new position desired at a predetermined velocity rate. Such information normally is pre-timed to correspond with a preselected timing rate in the digital computer. A position signal generator is responsive to such pre-timed digital information to generate a predetermined number of position signals intermediate of the pre-timed digital information to achieve the desired smooth operation of the servo motor.

Abstract: A method and apparatus for controlling the deceleration of a motor driven body in which deceleration is controlled as a function of the difference between the output energy of the driving motor and the kinetic energy of the driven body.

Abstract: An electronic circuit controls a non-linear electromechanical valve in order that the temperature of approximately 25 gallons of coolant water within a reservoir may be maintained within +2.8.degree. C. to -0.0.degree. C. of a set point temperature from 35.degree. F. to 100.degree. F. The valve regulates circulation of such coolant within a secondary cooling loop incorporating a non-linear heat exchanger for thermal exchange with building water flowing from 20 to 30 gallons per minute. The reservoir coolant water is subject to an essentially instantaneously variable thermal load of 0 to 20 kilowatts due to circulation through logic modules in a primary coolant loop. The electromechanical valve control circuit receives an external set point temperature signal, and a reservoir coolant temperature signal which is offset in conversion from degrees Kelvin to degrees Centigrade.

Abstract: A speed limiting indicating device for an internal combustion engine having an engine speed sensor providing a first signal indicative of engine speed, means responsive to said first signal for providing a speed limit signal indicative of said engine speed exceeding a predetermined speed limit, said speed limit signal means including a logic gate having its input connected to said first signal for providing said speed limit signal at said predetermined limit speed.

Abstract: A record player is described having a turntable which is rotated by a pulsed motor energized from a motor drive circuit. The motor driving circuit includes a negative feedback servo loop which includes means for detecting vibration of the arm. Means is further provided for generating an output in response to the vibration of said tone arm. A high-pass filter is provided having a cut-off frequency which is the same or lower than the resonance frequency of the tone arm. The motor is controlled by an output of the servo loop in proportion to an accelerated velocity of the tone arm when said tone arm is vibrating at less than the cut-off frequency.

Abstract: A separately excited D.C. motor employs an analog servo control responsive to a speed control input signal that controls the derivation of a compensating signal for the motor back emf. The speed control and compensating signals are combined to control the motor speed via an analog regulator. A digital shaft encoder responsive to the motor position supplies a pulsed signal to a comparator that is also responsive to a desired position signal that is derived from the speed control signal. The comparator derives an integrated error signal that is supplied to the analog regulator. Application of the speed control signal to the regulator is delayed if a thermal simulator for the motor characteristics indicates motor overheating. In response to the compensated, desired speed indicating signal indicating that the motor has been ordered to stop, the error signal is decoupled from the analog regulator.

Abstract: In a closed loop servo system in which the input signal is inaccessible and not available for measurement, but the error signal and output signal are both accessible and measurable, a filter configuration is provided which can be inserted into the error signal path of the system to reduce the undesirable effects of noise or other unwanted signals without appreciably affecting the closed loop dynamics of the overall system. In the generalized system a filter having the characteristics g(s) in LaPlace notation is inserted into the error signal path of the system to filter selected components of the error signal. A second filter having the characteristics h(s) which satisfies the equation g(s)+h(s)=1, is coupled between the output signal and the output of the filter having the characteristics g(s).

Abstract: In carrying out location control of a control object by decelerating a driving source for the control object over a suitable number of stages, this invention is based on the conception that inertia and strain occur in the control object, the driving source keeping such output as to allow a uniform motion of the control object and transmission mechanisms connecting them due to the uniform motion of the control object in a preceeding stage, and they exert significant influences over the location accuracy of the control object and wearing of the machine. In the present invention, therefore, the driving source of the control object is brought under deceleration control at such a timing where the strain occurring in the control object and its associated mechanisms becomes minimum.

Abstract: The disclosure relates in general terms to a sequence of automatic operations, with which a control loop is associated. By momentarily substituting a monitoring loop for this control loop, free-frequency auto-oscillation is set up in the sequence of automatic operations, and, since the monitoring loop comprises not only a gain amplifier but also a pure phase shifter, this setting-up of auto-oscillation is repeated successively at different frequencies. The device is applicable to the monitoring of any industrial plant for the purpose of regulating it.

Abstract: Load actuating servomechanism apparatus includes dynamic regeneration and a mechanically damped motor-load coupling to equalize and overcome a frequency-varying load/load drive train mechanical resonance. The drive circuitry comprises a per se conventional primary motor speed controlling rate feedback loop including a cascaded rate signal command source, summing error-signal producing node, and loop frequency response shaping filter and driver amplifier for exciting a load driving motor, and a rate tachometer signal feedback element connecting a measure of the motor output speed to a subtractive input of the summing node.To broaden the response band of the primary feedback circuit and accommodate a mechanical resonance otherwise interfering therewith, a secondary, positive feedback path supplements the input rate command with a signal dependent upon motor current, and thus upon motor load.

Abstract: An improved alternating current prime mover control system and method for, for example, the control of a valve position or other physical variable whose state can be sensed or calculated wherein the state of the physical variable is compared with a reference variable to generate, in conjunction with a waveform generator, a fixed amplitude signal that has variable time duration which feeds a part of the control system that drives the alternating current prime mover source in more than one direction.

Abstract: This invention relates to devices for damping oscillations in electromechanical and automatic control systems comprising actuators, various drives and flexible members providing mechanical coupling between the actuators and drive motors.In the general case the hereinproposed device furnishes a corrective signal being in phase opposition with respect to the a-c component of the signal taken from a moment or force transducer. This signal is applied to the input of the controlled drive, thereby damping mechanical oscillations. The device, according to the invention, may comprise several channels, each channel having such series-connected components as a fundamental-frequency sine-wave signal generation unit, a differentiating unit, a net time lag tuning unit, and an amplitude tuning unit.

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: The effective sensor width of a path following vehicle guidance system is enlarged by having a first gain control amplifier for amplifying the sum of the path sensor signals, a second gain control amplifier for amplifying the difference of the path sensor signals and a third amplifier, in tandem with the second amplifier for amplifying the output of the second amplifier once the second amplifier's output has peaked out. All three amplifiers are gain-controlled by the same negative feedback signal. The outputs of the first and third amplifiers are synchronously detected to provide an error signal for an electromechanical steering servo for the vehicle.

Abstract: A servo amplifier system for an accelerometer includes a torque coil. A torque coil is included in the output circuit of a first amplifier. A position sensor circuit develops a signal corresponding to the position of the coil which is applied to the input circuit of the first amplifier. An element, which may be a resistor, senses the current through to the coil and produces a voltage which is applied to a second amplifier having a low impedance output circuit. The output signal from the second amplifier is fed back to the input circuit of the first amplifier. Means are associated with the second amplifier to comply with the scaling and bandwidth requirements of the system.

Abstract: The stiffness of a second-order damped servo system with position and velocity feedback circuits is increased without affecting the command response, damping factor, or natural frequency of the system by adding an acceleration feedback circuit and maintaining a specified relationship between the effective gain of the acceleration feedback circuit and the effective gain of the servo driver.

Abstract: A servo system incorporating an attenuator for reducing the error signal an amount proportional to the magnitude of the error signal so as to minimize overshoot without affecting the stability in the system.

Abstract: A damping system is provided which is a self-adaptive damping system with an energy balance characteristic. The system has a conventional control chain and feedback loop which includes a detection means, an optional corrector, and a controllable damping device. In addition the system further includes an adaptation loop which is at least partly in parallel with the feedback loop and is coupled to and utilizes the information delivered by the detection device. The adaptation loop is coupled to and effects control of the damping device. The adaptation loop includes a comparator, an integrator and two parallel circuits furnishing to the comparator one signal which is a function of the energy of the slow mode of the system to be regulated in the occurrence of the process mode and a second signal which is a function of the product of the energy of the rapid mode and of the relation of the logarithmic decrements of these two modes.

Abstract: A control system using a duty cycle converter to convert an analog input into both a second order or velocity squared feedback as well as a set of clockwise and counterclockwise pulse trains the frequency of which is dependent upon the amplitude of the input signal. The velocity squared feedback is augmented by a position feedback from a stepper motor to provide optimum operation. To obtain optimum performance from a stepper motor, the rate of change of input pulses must not exceed a predetermined value for starting or stopping or the motor will react improperly to some of the pulses. The present system provides a linear increase in the step rate to a maximum and then a linear decrease in the step rate such that there is no overshoot beyond the requested analog input signal.