Abstract: A positioning system includes a plurality of actuators for driving an object to be positioned, a plurality of current output type amplifiers for amplifying drive signals from the actuators and for producing drive currents corresponding to the drive signals, and a plurality of acceleration sensors for detecting acceleration of the object in the neighborhood of the actuators. A feedback circuit negatively feeds back the outputs of the acceleration sensors to input sides of the amplifiers such that the actuators are driven in response to the drive currents.

Abstract: An encoder for indicating a position of a movable member and for generating at least two signals which are offset in phase from one another in accordance with movement of the movable member. The encoder includes a position detector and a presettable counter. The position detector generates a position reference signal indicating at least one reference position during movement of the movable member, and the presettable counter is preset for an absolute position of the encoder during movement of the movable member when the position reference signal is generated. The encoder can be constructed in a small size enabling use in servo systems and in industrial robots.

Abstract: An instrument for forming nanometric features on surfaces of materials having a motor driven support for moving a workpiece on an X-Y-Z axis, a scribing tool of nanometric proportion engagable with the workpiece and a laser system for sensing movement. The tool is mounted on piezoelectric actuating means and the entire system is under the control of a programmed computer processing unit.

Abstract: A system for controlling the locomotion of a biped walking robot having a body and a pair of legs each connected to the body through a hip joint and having a knee joint and an ankle joint and a foot at its distal end in accordance with predetermined locomotion data including a foot landing position of a lifted leg. A 6-dimensional force and torque sensor is provided at the body to detect an external force exerted on the robot. A moment is calculated from the external force and integrated during the external force exists. A coefficient is further determined in accordance with the trajectory of the lifted leg and is multiplied to the integrated moment. The predetermined foot landing position is corrected in response to the product and control values for the associated drive joints are changed such that the lifted leg will land at the corrected position, whereby preventing the robot from losing its stability when the external force exerts on the robot.

Abstract: In a method of controlling activation of a motor, based on a device number (unit address) set value A.sub.d which is determined exclusively for a disk device and a motor activation start time delay T.sub.d which is designated by a host control device, a motor activation start time T.sub.s which corresponds to the physical device number is calculated in the disk device. The motor activation start time delay T.sub.d is set as a command in an interface between the disk device and the host control device. The method also requires that a nonvolatile memory is disposed in the disk device. The motor activation start time delay T.sub.d is stored in the nonvolatile memory when designated. In controlling activation of the motor later, the motor activation start time T.sub.s is calculated from the information which is stored in the nonvolatile memory.

Abstract: The electronic postage meter includes a printing unit which is responsive to a plurality of motors for printing of a postage indicia in response to control circuit. The control circuit is comprised of a programmable microprocessor in bus communication with an accounting means having memory units for accounting for the postage printed by the printing unit responsive to the programming of the microprocessor. An integrated circuit includes an address decoding module means for generating a unique combination of ASIC control signals in response to a respective address placed on the bus by the microprocessor. A timer register is responsive to ones of the control signals from the address decoding module to enable writing of the timer data into the timer registers by the microprocessor. The timer unit is responsive to the timer data for generating one of a plurality of timing signal in accordance with timer data. The data also includes motor data.

Abstract: Multiple motion controllers for controlling servo motors are connected by a digital communications link so that controlled axes of the motion controllers may be slaved together regardless of their physical proximity. A given controller broadcasts position or command signals on the communications link in response to a request report message from any another controller. A second request report message may stop the broadcasting to conserve link capacity. Time shifting implicit in the link messages is corrected by estimating the velocity of the master axis and extrapolating the position to the local axes' time of updating.

Abstract: A control device for servocontrolling an object to a given position includes a motor, a coder connected to the motor, and a rig connected to the coder and the motor, the rig including (a) a counter and a subtractor which generate a position discrepancy signal on the basis of an output of the coder and an external set-point signal input to the subcontractor; (b) circuit paths each having a sampling device which receives the position discrepancy signal and samples this signal at a distinct frequency, each circuit path performing a different degree of differentiation; (c) a summing unit for receiving and summing outputs of each of the circuit paths; and (d) an amplifier for receiving an output of the summing unit and outputting a control signal which controls the motor.

Abstract: A drive system comprising an integrated gearhead motor system that produces relatively high torque output with minimal backlash. The present invention uses two axially mounted electric or air motors and gearhead assemblies integrated into a single unit. The two motor and gearhead assemblies are connected to concentric output drive shafts, and each output shaft mates to a respective gear of a split gear assembly. The split gear assembly is coupled to a drive shaft of a device that is to be driven by the system. A tachometer is coupled between the first motor and a position sensor is coupled to the drive shaft of the device that is to be driven. The tachometer and position sensor are coupled to a controller that is used to control the respective torques provided by the two motors in response to rate and position signals provided thereby.

Abstract: A machine with a movable element, such as a machine tool and its spindle carrier, that is powered by a motive means to move the element is provided with a counterbalancing system having at least two counterforce means operably connected to the movable element for exerting a counterbalance force on the movable element in opposition to the first force and wherein a first one of the counterforce means has a controllable servomotor means. The control means controls the servomotor means so as to cause the counterbalancing system to exert a substantially constant counterbalance force on the movable element in opposition to the first force. The second one of the counterforce means may be a hydraulic means having a hydraulic cylinder operably connected to an accumulator and a hydraulic piston operably disposed in the cylinder and connected to the movable-element.

Abstract: A cooperative differential drive system (20) for use in material handling and flight control and guidance systems, and the like. The drive system (20) may be employed in application that require high resolution task repeatability capabilities and the execution of precise position and force trajectory path following routines. A differential gear system (24) is driven by two servo-controlled actuators (22, 23) under control of a controller (21). The first actuator (22) is regulated at constant speed while the second actuator (23) is modulated at an appropriately varying speed to achieve a desired drive speed of a load. The second actuator (23) is controlled such that it dos not change rotational direction. Ultimate control of the load is achieved by way of the differential gear system (24) that combines the two actuator speeds to achieve the desired load speed. The differential gear system (24) is optionally coupled by way of a clutch system (25) to the load.

Abstract: A multi-shaft driving apparatus includes a plurality of motors each for rotating one of a plurality of shafts to be synchronously rotated, an encoder, provided for each motor, for detecting a rotational state of the shafts, a pulse generator for generating a pulse signal for rotating the shafts, and a motor control circuit, provided for each motor, for inputting the pulse signal generated by the pulse generator for rotating the shafts and a pulse signal detected by the encoder and used as a feedback signal. The motor control circuit has a PLL control section and a rotational angle phasing section so that a rotational angle phasing control loop is generated to perform a rotational angle phasing operation by the rotational angle phasing section so to as place the shafts in position at a driving start and after performing the rotational angle phasing operation, a rising and steady control loop is generated to perform an operation from a rise state to a steady state by the PLL control section.

Abstract: A numerical control apparatus for controlling a numerical lathe has a superimposing Z-axis control function in which, when a work is machined by the control of movement of a tool holder in the Z2- and X2-axis directions driving movement of a spindle in the Z1-axis direction, the variance of the position of the spindle in the Z1-axis direction as detected by a Z1-axis position detector is added to the value derived from a Z2-axis position detector which detects the position of the tool holder in the Z2-axis direction, and the position of the second tool holder in the Z2-axis direction is controlled using the result of the addition as the feedback value of the Z2-axis position of the second tool holder.

Abstract: A spindle rotation control method is provided capable of driving two spindles of a machine at the same speed with the same rotational phase. In response to a synchronizing control command from a numerical control apparatus, speed control is performed based on first and second speed commands calculated by using equations represented as a function of a synchronous speed command and parameters determined by the arrangement of a spindle rotational control system. When rotational speeds of the spindles reach the synchronous (same) rotational speed, first and second position deviation quantities corresponding to the synchronous rotational speed are calculated by using an equation represented as a function of a position control gain, and speed commands are converted into first and second moving commands, so as to perform position control loop processing based on the moving commands and the first and second spindle rotational quantities, and speed control based on a position control loop output.

Abstract: A numerical control apparatus for independently controlling the rotational velocity of a plurality of spindles. One or more spindles and one spindle rotational velocity are designated by NC data outputted by an NC data generating unit (1), the data in memories (3a-3n) corresponding to spindles designated by switching unit (2) is updated by the designated spindle rotational velocity, and motors (6a-6n) of corresponding spindles are controlled to rotate at the spindle rotational velocities stored in the memories (3a-3n).

Abstract: A servo system for controlling locomotion of a biped walking robot to follow up a target angle for each drive predetermined in series with respect to time. The control is stabilized by reducing the load on the on-board computer through the provision of an analog circuit for velocity control which has to be carried out in short control cycle and a digital circuit for positional control which can be carried out in relatively long control cycle. For reducing the control deviation to substantially zero, open-loop control is adopted for the motor angular velocity so as to prevent delay from arising in the joint angle control and position feedback control is conducted only in case where a deviation arises between the target joint angle and the actual joint angle owing to external disturbance or the like.

Abstract: A double spindle synchronous driving apparatus for synchronously driving first and second spindles, including: first and second motors for driving the first and second spindles, respectively; first and second rotational detection members for detecting rotational positions of the first and second motors so as to output first and second detection signals, respectively; first and second deviation counters which outputs first and second deviation signals in response to a position command signal and the first detection signal and in response to the position command signal and the second detection signal, respectively; a correction member which formulates first and second correction signals for the first and second deviation signals, respectively in accordance with a difference between the first and second deviation signals by fuzzy inference; first and second arithmetic members for performing arithmetic operation of the first deviation signal and the first correction signal and of the second deviation signal and t

Abstract: A multi-operation control system includes a plurality of slave computers each controlling its respective operation and forming at least one operating system. Each slave computer has a memory for storing a plurality of sequential movement instructions to be carried out by the slave and the micro-controller. Each slave computer monitors the operation it controls, compares the monitored operation with the current movement instruction and generates a flag signal if the monitored operation and current movement instruction differ by more than a preselected amount. This flag signal is transmitted to all of the slave computers of the operating system of which the slave computer is a part. The slave computers carry out their movement instructions in steps in working time increments. The step of movement to be carried out in a time increment is updated only when no flag signal is received by the slave computers, i.e.

Abstract: A method and apparatus are disclosed for reducing the cross-coupled movement in a member of a CNC machine caused by movement in another member of the machine through the structural dynamics of the machine. The method includes receiving the discrete position commands for a member oriented in one axis of movement for the machine, transforming the discrete position commands to attenuate frequency components that contribute to the movement coupled through the structural dynamics of the machine, and generating velocity commands from the transformed discrete position commands to control the servos that drive the members. The discrete position command transform is preferably a second order filter that implements the transfer functions of a digital notch filter and digital low pass filter. The second order filter that transforms the discrete position commands is implemented in a digital computer by state variable difference equations.

Abstract: A collision detection/drive stoppage method capable of promptly detecting a collision of machine operating parts driven by servomotors with a foreign object, and of promptly stopping drive of the machine operating parts upon detection of a collision, thereby preventing or lessening damage to a machine, etc., caused by the collision. A digital signal processor of an axis controller, forming a software servo system, periodically calculates a velocity deviation (.epsilon.v) in accordance with a command velocity (Vc) calculated based on a command from a main computer and an actual motor velocity (V) from a pulse coder of the servomotor (S2), determines whether the absolute value (.vertline..epsilon.v-.epsilon.v'.vertline.

Abstract: The invention relates to a spindle drive controller for a machine tool such as a numerically controlled lathe of the two spindle type. According to the invention, a drive control unit is enabled to separately control the spindles, or jointly control both spindles simultaneously. A switchover unit controls whether one or both spindles is controlled, and changeover units are provided for selectively feeding back speed and position feedback signals from one or the other of the respective spindles, depending on which spindle is being driven at that time.

Abstract: Disclosed is a cooperative operation system for a numerical control apparatus composed of numerical control apparatuses (CNCs) used in a transfer line. Each of CNCs (10, 20) is provided with a CNC control unit (11, 21), a switching circuit (12, 22) connected to the CNC control unit (11, 21) for switching an I/O signal, a RAM (13, 23) connected to the switching circuit (12, 22) for storing the I/O signal, a programmable machine controller (PMC) (16, 26) connected to the RAM (13, 23), and a serial transfer control circuit (15, 25) connected to the RAM (13, 23) for transferring the I/O signal to the another CNC. The PMC (16) receives or transmits the I/O signal of another CNC (20) through the serial transfer control circuit (15). The CNC (10, 20) can input and output the I/O signal thereof through the transfer control circuit (15, 25) to thereby increase the signal transfer speed, and thus a cooperative operation can be carried out at a high speed.

Abstract: A spindle control command method is provided for controlling a plurality of spindless by a single numerical control device (CNC), and switching between individual control and synchronous control of a plurality of spindles (1, 3) is effected by a program command (9). Namely, whether the spindles (1, 3) should be controlled individually or synchronously is commanded by an NC program (9), and the CNC carries out switching to the individual spindle control or to the synchronous spindle control in accordance with the command given.

Abstract: A synchronizing control apparatus for synchronously rotating master and slave main spindles of a pin grinder, wherein a servomotor for the slave main spindle is rotated at a speed corresponding to a compensated command value while the master main spindle is rotated at a speed corresponding to a noncompensated command value. The compensated command value is calculated based on a synchronizing error between the master and slave main spindles at a predetermined interval longer than the length of instable condition of a servo loop for the slave main spindle. When the synchronizing error is larger than a predetermined limit value, the command value for the slave main spindle is gradually compensated in order to prevent the compensated command value from changing too abruptly.

Abstract: First, second, and third compensation signals are generated from the information on the position and speed of the first servo system having a speed control loop as a minor loop. The speed error of the speed control loop of the second servo system which has the speed control loop as a minor loop and uses a signal obtained by sampling the position detection signal, executing a digital calculation process on the sampled signal to obtain a speed signal and integrating the speed signal as a position command signal or a signal obtained by sampling the position detection signal of the first servo system and executing a digital calculation process on the sampled signal as a position command signal is compensated by the first, second and third compensation signals. Thus, even in cases where the acceleration and deceleration of the first servo system are executed even at constant power, positional synchronizing error is not generated.

Abstract: In a system equipped with a plurality of magnetic disk devices, one magnetic disk device is used as a device (master unit) for generating reference signals for rotating other plurality of devices in synchronism. Other one or more magnetic disk devices (slave units) are rotated in synchronism following the reference signals generated from the master unit. In order to maintain the synchronism of revolution between the master unit and the slave units, the conditions of revolution of the two spindle motors are compared to maintain the synchronism of revolution. Index pulses recorded on the magentic disks of the master unit and the slave units are used as reference signals for maintaining synchronism of revolutions. Index pulses from the master unit and the slave units are compared to find a phase difference signal and a period difference signal, and the rotational speed of the slave units is compensated by using these two signals.

Abstract: A biaxial rotary drive unit drives an antenna Ant on a vehicle for rotation in both azimuthal and elevational directions. A first axis Y represents a vertical axis, and an azimuth turntable 120 is rotatable about the first axis. The second axis X represents a horizontal axis, and the antenna Ant is mounted on the turntable so as to be rotatable about the second axis in the elevational direction. The turntable 120 represents a gear of an increased diameter, which is meshed by a gear 144 of a reduced diameter to be driven thereby for rotation. A cylindrical shaft 116 extends through the center of the larger diameter gear 120. The cylindrical shaft 116 carries a ring gear meshing with a pinion gear 154, which serves driving the cylindrical shaft 116 up and down. The vertical movement of the cylindrical shaft 116 is transmitted through a link 115 to drive the antenna Ant for rotation in the elevational direction.

Abstract: Printed elastic bands are made by piercing, evacuating and flattening an elastic tubing and washing and scrubbing and drying the upper surface of the tubing, aligning a tubing on a conveyor and moving the tubing upward toward a printing head and quickly downward away from the printing head while maintaining the tubing flattened. The printing is devolatilized and cured while the tubing continues to move to the cutoff point. Nip rollers drive a tubing onto a cutoff platen, a final roller near the edge of the platen has a higher surface speed than the nip rollers to flatten the tubing. Printing on the tubing is sensed and rotating knives are sensed and the speed of the nip rollers is controlled to cut the tubing between the printed areas. Severed printed bands are removed by vacuum and are discharged from a cyclone separator.

Abstract: A motor control apparatus according to this invention is for setting control parameters which correspond to a motor model in a case where machine tools controlled by a numerical control unit or the like employ a large variety of motor models, with control parameters corresponding to these motor models being set and changed externally. Accidents due to erroneous setting of the control parameters is reliably prevented. The apparatus includes registering means (22) in which a specific model code representing the control parameters of a respective motor model is registered in advance, and memory means (21) for temporarily storing the set control parameters as well as a model code transferred along with the control parameters. The model code registered in the registering means (22) is compared with the transferred model code to identify the motor model.

Abstract: An apparatus for measurement of absolute position of a movable machine member is provided. The machine member is moved by a motor and reduction device producing rotation of the machine member in proportion to relative rotation of the motor rotor and motor stator. Two angular position measuring devices provide output signals representing relative positions related to the machine member position and differentiated one from another.

Abstract: A bi-axial synchronous driving apparatus which includes: a set of motors for respectively driving two axes; rotation detecting devices for detecting rotational positions of the respective motors; a set of deviation counters to which a common position instruction signal and detection signals of the respective rotation detecting devices are applied; a correcting unit to which deviation signals outputted from the respective deviation counters are applied, so as to form correction signals with respect to the respective deviation signals based on an integration of a difference between each one of the deviation signals and the other corresponding deviation signal; a set of adding devices for adding the deviation signals outputted from the respective deviation counters to the correction signals; and a set of driving devices for driving the respective motors based on control signals outputted from said respective adding devices.

Abstract: In a method for performing a synchronized superposed operation of two servomotors, controllers for the servomotors perform the control for achieving the synchronized superposed operation by: calculating, for each of the servomotors, the difference, or differences, between the ideal speed and/or position deviations obtained from a control command and the actual speed and/or position deviations obtained from the rotation of the servomotor; calculating a speed correction quantity, or a speed correction quantity and a current correction quantity, from the discrepancy, or discrepancies, between the differences calculated for both of the servomotors; and adding the correction quantity, or quantities, to a speed command, or to a speed command and a current command, given to the subsidiary shaft side. Thus, a synchronized superposed operation of servomotors in which speeds and responses of the main shaft and the subsidiary shaft are well balanced therebetween can be achieved.

Abstract: A spindle drive system of a machine tool, wherein a control mode changeover section of a control unit selects one of both a speed control mode for controlling a rotational speed of a spindle through negative feedback of the rotational speed of the spindle and a position control mode for controlling a rotational position of the spindle through negative feedback of the rotational position of the spindle, and a gain changeover section changes speed loop and position loop gains to a greater value during cutting operation than during non-cutting rapid feed operation when the position control mode has been selected.

Abstract: A toroid turns counter for a toroid with at least one winding with turns to be counted by electric counting device connected to said winding having a test winding with an opening for receiving the toroid, a movable contact arm for electrically closing the opening after the toroid has been received in the opening, an activating arrangement which is coupled to the contact arm, and controls coupled to the activating arrangement for controlling the closure of the contact arm.

Abstract: During synchronous control, a first servo motor controls a position of a first spindle system and a second spindle system having a second servo motor makes calculations for estimating the torque required for the second servo motor and gives a command, so that, when a rotational phase difference between the two servo motors exceeds a predetermined value, the rotational phase difference is made equal to zero by a rotational phase difference signal. A torque command to the first servo motor, an inertia ratio between the first and second servo motors, the rotational resistance of the two spindle systems and so on are input to a torque estimator which makes calculations for estimating the torque required for the second servo motor. The estimated torque is used to control the second servo motor. The two servo motors thus generate the appropriate torque when a work held between the two spindle systems is processed. It is therefore possible to significantly reduce the torsional torque applied to the work.

Abstract: A multi-spindle synchronous drive unit for synchronously driving a plurality of spindles, includes a plurality of motors for respectively driving the spindles, a plurality of encoders for respectively detecting rotational positions of the motors, a plurality of phase locked loop control units for respectively controlling a drive of the motors and for receiving as feedback signals detection signals respectively output by the encoders, a reference pulse oscillator for outputting a pulse signal, and a plurality of multipliers for multiplying the pulse signal by multiplication factors respectively corresponding to rotational speed ratios of the spindles and for respectively outputting speed command pulse signals to the phase locked loop control unit.

Abstract: Disclosed is a synchronous control system for effecting a synchronous and superimposed operation among different channels of a multi-channel-control machine tool. A follow-up error amount (.epsilon.3) of a servomotor responsive to a superimposing instruction is simulated, a difference is determined by subtracting the follow-up error amount (.epsilon.3) to the superimposing instruction from a follow-up error amount (.epsilon.2) of a servomotor for a superimposed operation axis (Z2) and the difference is compared with a follow-up error amount (.epsilon.1) of a servomotor for a synchronous operation axis (Z1) to produce an alarm when the comparison indicates the operation of the servomotors is synchronized and superimposed.With this arrangement, a synchronous error can be checked when a superimposed operation of the servomotors is effected.

Abstract: A control device for controlling displacement of a magnetically supported moving member according to a command. A feedback circuit detects the displacement of the moving member to servo-control the same to thereby ensure stability and robustness of magnetic supporting. A feedforward circuit has an input terminal receptive of a command and an output terminal connected to the feedback circuit, and cooperates with the feedback circuit while not disturbing the stability and robustness of the magnetic suppporting for controlling the displacement of the moving member according to the command.

Abstract: A numerical control apparatus for controlling a multiple-axis and multiple-channel machine tool by controlling multiple axes through multiple channels. A main processor (1) for executing data processings other than servo system processing, and an operator interface module (2), etc. are connected to a first bus (7). A plurality of servo command generating processors (10, 20, 30) for processing input data and producing a servo command for each channel are connected to the first bus (7) and a second bus (41). The second bus (41), which is connected to a plurality of servo control processors (42-45), transfers only servo command data and the first bus (7) transfers all other data. Accordingly, servo commands can be produced at a high speed, and thus a high-speed control of a multiple-axis and multiple-channel machine tool can be effected.

Abstract: A band pass filter multiplies an input waveform with first trigonometric functions at a plurality of frequencies and then filters the products. Furthermore, with that filtering step, the products are multiplied, or their phase is changed by a predetermined value, and the results are multiplied by the inverse of the trigonometric functions.The sum of this, for all frequencies, generated a filtered output waveform. Where the input waveform has two components, the corresponding outputs can be obtained from the read and imaginary components of the output waveform. In practice the trigonometric functions are produced by sine and cosine components at each frequency. In this way a band pass filter device is formed which is suitable for use in the control system of an apparatus which must be controlled continuously, such as a control system for a rotor.

Abstract: A numerical control device for a multi-axis lathe which is capable of controlling movements of a plurality of tools simultaneously. With the numerical control device, the movement of a first tool in a Z-axis direction is controlled according to the movement of a workpiece to be machined and the other movement of remaining tools in the Z-axis direction are controlled taking the Z-axis movement of the first tool into consideration, so that the different machining operations using different tools can be attained simultaneously or successively.

Abstract: A motor drive method is provided which is capable of preventing suspension of operation of an industrial robot, and preventing deviation of the track of movement from a command track, attributable to an overload state of a motor. Output torque command values for motors for various axes of the robot are detected (S1). When any one of the detected values exceeds a predetermined value, which is determined in accordance with the maximum output torque of each corresponding one of the motors for the various axes, an amount of move command per unit time, for every one of the axes, is reduced. The amount of move command per unit time is reduced by using the torque command values thus increased, the product of an override value and a coefficient obtained in accordance with the differential of the torque command values (S3, S6 and S14), whereby the overload state of the motor is prevented.

Abstract: A numerical control apparatus according to the invention has a mode designating interface for deciding a control mode and an interface which receives position and velocity commands, these interfaces being interposed between the apparatus and a servo-processor. A mode for controlling the servomotor is automatically decided internally of the numerical control apparatus. Changeover is possible in which the servomotor is used as a motor for positional control or in order to control rotational velocity in the manner of a spindle motor to achieve continuous rotation.

Abstract: The motor controller system controls the respective motors of a plurality of cooperative apparatus associated with a article processing system, the article processing system for performing a plurality of functions upon an article traversing the article processing system and comprises a motor driver board having a plurality of input channels and a plurality of respective output channels. The motors are in line communication with a respective one of the output channels of the motor driver board. A programmable microprocessor is in bus communication with the driver board's input channels. A plurality of sensors are respectively mounted to each of the apparatus and in bus communication with the programmable microprocessor, the sensors being strategically located on the apparatus to provide such information to the microprocessor as article size, position and velocity information and to provide apparatus operation information.

Abstract: A multiple-articulated robot control apparatus eliminates robot arm vibration by feedback-compensating disturbance due to interference torque when the robot arms are driven. The apparatus includes an arithmetic circuit (8) for computing mutual interference torque values for respective ones of the arms, a status observing circuit (2) for reproducing a status variable from a torque command and actual velocity of each servomotor, a conversion circuit (4) for converting an output of the status observing means into a corrective value of torque produced by disturbance acting upon the servomotor, and a correcting circuit (9) for correcting an error signal of the torque command of the servomotor by the converted corrective value and the interference torque value. Disturbance of each arm with regard to driving torque is eliminated. The apparatus is adapted to correct estimated disturbance torque.

Abstract: The multiple channel servo system engages in bus communication with a micro-controller, motor driver for driving a plurality of motors and motor servo for providing servo information for selected ones of the motors. The micro-controller generates respective motion command profile information for each of the selected motors. RAM is provided for receiving and storing the motion command profile information from the micro-controller for the selected motors. The servo system sequentially compares the respective servo information with the respective motor command information and generating respective motor control information for the respective motor for causing the motor driver to cause the respective motor to closely track the respective motor command profile. RAM memory is also provided for receiving and storing microcode for each of the selected motors.

Abstract: A step motor which, in addition to an exciter system for step-by-step movement, is provided with an axial exciter system. As a result of the direct or indirect influence of the magnetic field generated by the secondary exciter system on the rotor which is supported, so as to be able to move in an axial direction with respect to the stator, the rotor can be induced to move in a direction perpendicular to its step-by-step rotary motion, as well. Both exciter systems can be energized independently of one another, so that step-by-step rotary movement can be performed at any axial position of the rotor and the rotor can be made to move in an axial direction during its rotary movement as well as when it is at rest.

Abstract: An original drum and a recording drum are driven independently by individual synchronous motors. Encoders output respective rotation timing pulses (P.sub.a, P.sub.b) at every rotation of the recording drum and the original drum. If an interval separating the timing pulses (P.sub.a, P.sub.b) becomes smaller than a prescribed value, a scanning line deviation control circuit generates a motor control signal (T.sub.b) which interrupts the delivery of electrical power to the faster moving motor for a limited period such as to restore a correct relationship between the timing pulses.

Abstract: A rotation control system for preventing unbalance vibrations and synchronous disturbance vibrations of a rotary member suspended by a magnetic bearing. This system includes a vibration detector which detects radial vibration of the rotary member. On the basis of the detected radial vibration, a compensating signal which has the same amplitude and cycle as the vibration component having the rotational frequency is generated. The difference between the detected vibration and the compensating signal is obtained and used for controlling the radial position of the magnetic bearing.

Abstract: In a method for numerical position control of motordriven shafts whose rotations are to be synchronous with one another under a certain transmission ratio a control loop is provided for each shaft. A speed setpoint, weighted with the corresponding transmission ratio, is applied as a position setpoint per unit of time simultaneously to the control loops of the respective shafts. If the actual speeds of the shafts differ from one another due to a disturbance within the controlled system, the difference between these actual speeds is used to readjust the speed and the position within the speed controlled section of one of the control loops.