Abstract: A method for correcting deflection intended to easily determine displacement of an endpoint of the robot caused by deflection of the robot, or the like, as well as to make accurate correction according to a respective configuration of the robot on the basis of deflection angles of individual axes of the robot. In this method, joint torques acting on the axes (W axis, U axis, . . . ) of the robot 1 are first determined, and the deflection angles of the axes are then determined on the basis of the joint torques. Command values for the axes are corrected on the basis of the deflection angle of each axis, whereby the endpoint position of the robot is accurately corrected to a command position Xd0. Further, on the basis of determined deflection angles of the individual axes, the robot 1 is made to recognize the actual position Xd1 of its deflected endpoint.

Abstract: A Stirling-cycle cryogenic cooler that employs a vibration control procedure based on adaptive feedforward principles. The vibration control procedure is particularly adapted for use as a spacecraft cryogenic cooler, and may be used to cool a detector array or other sensor located on the spacecraft. The vibration control procedure suppresses vibrational forces that occur during operation of the cooler. The cooler comprises an expander module and a compressor module. The expander and compressor modules employ separate motors that respectively drive an expander piston and a compressor piston, and a balancer piston is employed to dynamically balance the respective expander and compressor pistons. In the control procedure, current command signals are injected into a selected motor drive of either the compressor or expander module. The injected current command signals comprise higher-order harmonics with adaptively determined phases and amplitudes that provide for complete force cancellation in the cooler.

Abstract: An improved electromechanical actuator controller or system, counteracting the control stability degradation caused by motor interaction with the load dynamics (actuator compliance), having decreased sensor noise sensitivity responses and minimal compensation implementation requirements. The controller includes a motor rate sensor and an actuator position sensor, whose signal outputs are combined in a complimentary filter to blend the dissimilar sensor signals to achieve the desired control signal. The complementary filter time constant is chosen to result in a stabilizing quadratic phase lead which allows the controller bandwidth to be increased to provide the desired faster electromechanical actuator controller time responses.

Abstract: The invention fulfills new goals for redundancy resolution based on manipulator dynamics and end-effector characteristics. These goals are accomplished by employing the recently developed configuration control approach. Redundancy resolution is achieved by controlling the joint inertia matrix or the end-effector mass matrix that affect the inertial torques, or by reducing the joint torques due to gravity loading and payload. The manipulator mechanical-advantage and velocity-ratio are also used as performance measures to be improved by proper utilization of redundancy. Furthermore, end-effector compliance, sensitivity, and impulsive force at impact are introduced as redundancy resolution criteria. The new goals for redundancy resolution allow a more efficient utilization of the redundant joints based on the desired task requirements.

Abstract: An apparatus is disclosed which controls the speed of a motor driving a load. A speed controller finds the difference between a command speed value of the motor and a detected speed value of the motor and generates a command current value of the motor on the basis of the difference. A current controller controls current in the motor on the basis of a difference between a command current value received from the speed controller and a detected current value. A torque detector is mounted on the shaft, whereby the motor is connected to the load, for detecting torque acting on the shaft, and an adder adds the detected torque signal detected by the torque detector to the command current value received from the speed controller, the torque detection signal being a correction signal for controlling acceleration torque of the motor.

Abstract: An actuator for a joint comprises a bladder-shaped chamber 5 whose one end is secured to an arm 2 by a mounting 6, whilst a bundle of fibres 7 extend from the other end of the chamber member 5 to a junction 8 on another arm 3. The rear wall 9 of the chamber member 5 is formed from woven bi-directional fibres 10 whilst the outer wall is defined by an array of high tensile fibres 11, at least some of which extend from the fibre bundle 7. The fibres 7, 10 and 11 are embedded in elastic material. When a pneumatic or hydraulic fluid is pumped through an inlet 12 to the chamber member 5, the latter expands and the fibres 11 bow outwardly, thus pulling on the fibres 7 and raising the arm 3, with the respect to the arm 2, to lift a weight 13.

Abstract: A five degree-of-freedom positioning device includes a manipulator shaft for manipulating an object to a desired position and orientation. Two sets of stator permanent magnets are spaced along an axis of the manipulator and arranged in parallel planes transverse to the manipulator axis so as to provide therebetween magnetic fields substantially extending along the axis. Interposed between the sets of permanent magnets are axially spaced sets of electrically energizable coils also arranged in parallel transverse planes. The coils are energized to produce coil fields that interact with the magnetic fields of the permanent magnets for generating the Lorentz force which acts on the manipulator shaft to effect two translational movements of the manipulator shaft along two mutually orthogonal axes perpendicular to the manipulator shaft axis and three rotational movements about the three mutually orthogonal axes including the manipulator shaft axis.

Abstract: A control for a DC motor coupled to a user interface to provide a counterforce which simulates a weight stack in an exercise machine. The control includes a position transducer coupled to the motor to provide a signal proportional to the displacement of the user interface. In one embodiment a circuit is provided to generate a control signal which follows the displacement signal when it is less than a maximum torque signal, the control voltage following maximum torque signal when it is less than the displacement signal. In a second embodiment a microprocessor control unit is responsive to the displacement signal to provide a control signal for the motor which starts increasing from a first value when the user interface is displaced an initial amount and which continues gradually increasing to a maximum value as the user interface is moved through a given displacement from the initial displacement.

Abstract: A system (11) for monitoring and controlling the movement of a mass (12) along a predetermined path (14) by a motor-driven flexible member (20) is provided to modulate the motor drive output so that the actual velocity of the mass corresponds more closely to the desired target velocity profile. The system preferably employs a dual loop servo system wherein an outer servo loop uses conventional linear encoding techniques and is supplemented by an inner servo loop utilizing a sensor (27) that detects a physical characteristic of the flexible member representative of the relative velocity of the mass. Relative velocity transducers utilizing magnetic circuits and operating according to variable reluctance principles for generating relative mass velocity signals directly are disclosed.

Abstract: A controller for a fine positioning device constructed of planar structural units connected symmetrically and equipped individually with planar flexible beams arranged in an opposing relation between two rigid members and actuators for applying forces between the two rigid members includes displacement detection devices, displacement setting devices, sensor devices for determining the degree of each translational displacement and the degree of each angular displacement, and control devices for controlling the voltages to be applied to the respective actuators.

Abstract: A method and apparatus to control a robot or manipulator configuration over the entire motion based on augmentation of the manipulator forward kinematics. A set of kinematic functions is defined in Cartesian or joint space to reflect the desirable configuration that will be achieved in addition to the specified end-effector motion. The user-defined kinematic functions and the end-effector Cartesian coordinates are combined to form a set of task-related configuration variables as generalized coordinates for the manipulator. A task-based adaptive scheme is then utilized to directly control the configuration variables so as to achieve tracking of some desired reference trajectories throughout the robot motion. This accomplishes the basic task of desired end-effector motion, while utilizing the redundancy to achieve any additional task through the desired time variation of the kinematic functions.

Abstract: A fine positioning device is formed of a rigid support member; a first set of radial flexible-beam displacement mechanisms provided symmetrically to each other on the support member to produce angular displacements about a first axis; a second set of radial flexible-beam displacement mechanisms provided symmetrically to each other on the support member to produce angular displacements about a second axis which is perpendicular to the first axis; a third set of radial flexible-beam displacement mechanisms connected to either one of the sets of radial flexible-beam displacement mechanisms to produce angular diaplacements about a third axis which is perpendicular to both the first and second axes; and a fine motion table fixed on the radial flexible-beam displacement mechanisms which are other than those connected to the radial flexible-beam displacement mechanisms for producing angular displacements about the third axis.

Abstract: A fail-safe arrangement for an electrical power steering system is directed to providing a control arrangement for a power steering motor which will prevent abnormal operation from having adverse impact. The control system detects the welding or sticking together of closed relay contacs and functions to prevent such a situation by monitoring the motor terminal voltage so as to cut off power above a predetermined value regardless of position of the relay contacts.

Abstract: A motion controller for the head carriage of an ink jet printer comprises a target signal generator providing constant velocity reference input to a servo loop controller. Also, two levels of current are applied to the drive motor during direction reversal, a lower one during deceleration of the carriage, and a higher one during acceleration of the carriage. The timing of the two current levels is determined by inputting a rectified velocity signal into a slope detector. A comparator converts the output of the slope detector into a binary signal for controlling the motor current level.

Abstract: A headrest control system for a motor vehicle equipped with a driver's seat and rear seats having adjustable headrests mounted thereon is disclosed which includes a driving motor for moving the headrest of the rear seat between an operative position for use and an inoperative retracted position, a first switch provided for actuating the driving motor, a second switch for actuating the driving motor, a memory for storing data of an optimum operative position of the headrest, and a sensor for detecting whether the rear seat is occupied by a passenger or not.

Abstract: A supporting device including a first member which supports a springy means for resiliently supporting a second member. The supporting device includes a detection for detecting displacements of the springy with respect to the first member in accordance with the movement of the second member and a biasing which applies a force to the springy from the same direction as or from a direction opposite to that of the displacement for changing the elasticity of the springy in accordance with the movement of the second member.

Abstract: A method for controlling the noise and vibration of machine tools in correspondence with environmental control standards includes determining a first level of noise and vibration generated by the machine tool during its operation, selecting a desired level of noise and vibration generated by said machine tool during its operation, and controlling the operation of said machine tool so that said machine tool operates at a second level of noise and vibration, wherein said second level of noise and vibration is below said desired level of noise and vibration. In a specific embodiment the stroke speed of the stroke section of a plate processing machine is controlled.

Abstract: The motor-driven power steering unit according to the first aspect of the present invention is able to decrease the amount of current being applied to the motor if the steering force exceeds a predetermined level. The motor-driven power steering unit according to the second aspect of the present invention is able to decrease the amount of current being applied to the motor when the steering speed is less than a predetermined level.

Abstract: A control topology for a servo motor carriage drive includes a strain gauge coupling the carriage to a motor-driven belt to provide a signal representative of the flexure of the belt. A velocity signal is taken from a linear encoder on the carriage. These signals are used in inner and outer feedback loops for controlling the velocity of the carriage as it travels along a predetermined path.

Abstract: A torsion transducer for providing electrical position and angular velocity signals for a device driven in a bidirectional partial rotational mode, such as commonly found in the rotary actuator arm of a disc drive for rotating computer memories. The torsion transducer comprises a torsion bar in the form of a wire, with one end attached to the rotating element of the actuator arm and the other to a piezoelectric transducer operating in the shear mode, which is anchored to the stationary frame of the device. As the torsion bar is twisted by the angular motion of the rotary element, torque is applied to the piezoelectric transducer, which then generates an electrical signal that can be processed to represent position and angular velocity of the rotary elements of the actuator arm.

Abstract: In an automatic lathe, a touch trigger probe (4) is calibrated (datumed) against an item (6) having a known reference dimension, instead of against the lathe chuck (2) or against a surface machined in a workpiece. The calibrated probe is then used to touch two diametrically opposed points of a feature (11) centered with respect to the axis of rotation of the chuck (2). From the mean of the co-ordinates of the two points touched, there is calculated an offset related to the difference between the assumed axis of rotation and the actual axis of rotation. This calibrates the machine to compensate for any drift between the actual axis of rotation and the machine's measurement origin.

Abstract: A fine positioning device is formed of a central rigid portion, a first set of outwardly-extending portions extending symmetrically along a first axis from the central rigid portion, a second set of outwardly-extending portions extending symmetrically from the central rigid portion along a second axis which is perpendicular to the first axis, a first set of parallel flexible-beam displacement mechanisms provided symmetrically to each other with the first set of outwardly-extending portions respectively to produce translational displacements along the second axis, and a second set of parallel flexible-beam displacement mechanisms provided symmetrically to each other with the second set of outwardly-extending portions respectively to produce translational displacements along the first axis. Three set of radial flexible-beam displacement mechanisms are provided to produce angular displacements about three axes.

Abstract: An electronic tractor hitch control system in which the position of an implement hitch relative to a tractor can be set using a main control operable by a tractor operator from his normal location on the tractor and can also be set using a secondary control located at a location remote from the normal operator's location, such as on the rear of the tractor fenders. The system is arranged so that any implement position signal set using the secondary control is opposed by a smaller hitch positioning signal generated within the system so that the speed of movement of the hitch in response to hitch positions set using the secondary control is moderated. The system also includes circuitry for detecting short circuits in parts of the system located in vulnerable locations.

Abstract: This application deals with apparatus for calibrating an automated machining apparatus. The calibration apparatus comprises a tool probe and a system accuracy check gauge rigidly fixed to the workpiece loading mechanism of the machining apparatus. This arrangement allows variations in the locations of the cutting edges of the tools used in the machining apparatus to be taken into account in the machining operation and also allows checking of the dimensional and positional accuracy of the machining apparatus against a precisely known reference.

Abstract: A position servo system is described for positioning a member mounted on a spring. The spring provides a force opposing the motion of the member from an initial position. A position actuator, for example a motor, applies a force in response to a position request signal for moving the member to a desired position. A portion of the position feedback signal is applied from a position sensor to the motor as a positive feedback signal to compensate for the force of the spring. A steady state position error of the servo system is thereby substantially reduced to zero. A circuit and method for calibrating the positive feedback signal are also described.

Abstract: A machining control method for an electrical discharge machine compensates for the lagging of the wire electrode as the electrode is advanced from a straight line portion to a change of direction portion of the outline to be machined. The wire electrode is advanced from the straight line portion of the outline until it reaches the change of direction point of the outline and is then halted until the wire electrode lag is corrected. During the halt, machining takes place under a different set of conditions. When the lag is corrected, the wire electrode is advanced along the change of direction portion under a third set of machining conditions. When the wire electrode reaches another straight line portion, the outline machining of the workpiece is resumed under the first set of machining conditions. Also disclosed is a method of controlling the positioning of a workpiece by trial positioning a large number of workpieces having a variety of weights under a variety of load conditions of the control motor.

Abstract: A system is provided for adaptively limiting the feed rate of a milling machine's positioning axes during a milling operation. Normal operation of the milling machine is controlled by a numerical control system (26). The invention utilizes strain gauges (18, 20) which sense loading force on the cutting tool during milling. A computer (24) is operatively connected to the strain gauges (18, 20). The computer is programmed to receive signals from the strain gauges and to use such signals to automatically override the programmed feed rate in the numerical control system (20), to maintain a specified peak side load on the cutting tool.

Abstract: A multi-layered tactile sensing skin is provided for a robotic arm or the like. The skin includes adjacent layers of electrically insulative film having opposed contiguous surfaces. An electrically conductive carbon based compound is applied uniformly to one of the surfaces, while the other surface is selectively coated with silver oxide to form a series of pairs of first and second electrically conductive regions separated from one another by a dielectric gap. The carbon based conductor bridges the gap betwen the conductive regions in each pair, permitting flow of electrical current between the regions. The current flow increases with an increase in pressure over the interface between the layers of film, and the amperage increase can be utilized to trigger a signal to the robot power supply, to decelerate, stop or reverse arm movement.

Abstract: A fine positioning device is constructed of a parallel flexible-beam displacement mechanism and/or a radial flexible-beam displacement mechanism. The former displacement mechanism comprises a first rigid portion rigid against forces, a second rigid portion rigid against forces, plural parallel flexible beams connecting the first and second rigid portions together, and a first actuator adapted to have the plural flexible beams undergo bending deformation. The latter displacement mechanism comprises a third rigid portion rigid against torques, a fourth rigid portion rigid against torques, plural radial flexible beams connecting the third and fourth rigid portions together, and a second actuator adapted to have the plural flexible beams undergo bending deformation. The fine positioning device can obtain fine linear displacements and/or fine angular displacement with good accuracy. This invention also facilitates the construction of multi-axis positioning devices.

Abstract: A power torque servo system (100) for roller swaging (122), including a servomotor (132) having a gear box (134) with a drive shaft (138). The motor is supported on two members (150, 152) on opposite sides of the drive shaft (138) and a third member (146) on which the motor may pivot. Strain gages (154, 156, 158, 160) are mounted on the members (150, 152) to measure servodrive reaction torque in the shaft when the shaft is rotated by the motor to function as a swage drive or in another torquing operation. There are switches (236) to set a final torque value to be obtained in the servo system and an electrical servo system for receiving the strain gage measurement signals to provide a smooth low speed approach to a final torque value (182) in the shaft (138) and to eliminate any dynamic torque overshoot in the shaft.

Abstract: Control force errors are automatically eliminated in aircraft, especially licopters. Such errors may occur because of disturbing forces that act on a control stick (1) for the elevator and/or rotor blade adjustment. The following features are combined. A main control drive (3) for the adjusting of the elevators and/or rotor blades is connected through a control linkage (2) with the control stick (1). A spring box (5) with a pretensioned spring (17) is connected through a control rod (14) to the control stick (2) and to one end of the spring box (5). A trimming rod (15) of a trimming motor (4) is operatively connected to the other end of the spring box (5). To compensate the disturbing forces caused by the inertial mass forces acting upon the control stick (1) as much as possible there are further provided two displacement pickups (6) and (7) or a single displacement difference forming pickup (16). A first summing circuit (8) receives the output signals from the two pickups (6, 7).

Abstract: A capacitance article density monitor which is adjusted to have a zero voltage output when no articles are positioned adjacent a sensor and wherein the output of the circuit may be utilized directly to control a variable speed drive for a machine to which articles are being directed depending upon the density of such articles in a conveying area in advance of the machine. This abstract forms no part of the specification of this application and is not to be construed as limiting the claims of the application.

Abstract: An automatic machining apparatus includes means of sensing or measuring displacements of a work model, manual operation means for manually operating said sensing means, a displacement determining device for measuring the pressure difference responsive to the displacement measured by said sensing means, means for conversion of said pressure difference into electric signals and transmission of said signals, means for memorizing said signals transmitted from the signal transmitting means and storing the information in response to said transmitted signals, including means for computing the positional difference or disagreement between the sensing means and the work model, means for displacing machining means for machining a work piece in accordance with the necessary information provided from the memory stored in the memorizing means, means for slidably, rotatably or withdrawably mounting the sensing means nearby the machining means, means for holding the work model or work piece, means of controlling the holding

Abstract: A "mode switch" is used for smoothly switching a servovalve controlled device such as an SMC press, in particular, from control under one parameter to control by another. The mode switch provides a very smooth transfer of control from displacement control between two relatively movable parts to force control to provide for controlling the force exerted by actuators acting between the two parts. The mode switch electronically tracks the signals so that when the switching is made the signals are precisely equal to prevent abrupt changes in the control signals. This smooth transfer is achieved even under active control, that is when both control signals are changing in value.

Abstract: A driver for positioning the postage amount handles of a postage meter, the driver including motors which, in response to control signals from a postage computer, axially displace shafts along paths generally parallel to the paths of the postage meter handles. The shafts support actuator fingers which couple the shaft movement to the respective handles. An optical interruptor for each shaft senses various shaft positions and provides signals to the postage computer which are used in part to develop the control signals.

Abstract: A program controlled workpiece manipulator has a load cell supported between the manipulator clamp and the positioning elements which generate signals proportional to the various components of the forces exerted on the workholder by external instrumentalities. To generate a desired control program for the manipulator the outputs of the load cell and of the position transducers for the manipulator drive servos are used to generate command signals for the drive servos which urge motion of the clamp to reduce the externally imposed forces. The clamp is then manually grasped and urged toward the desired motion and the outputs of the position sensors are recorded during the motion to create a control program which may be replaced to control the manipulator to duplicate the motion.

Abstract: A voice coil type linear motor controls the movement and positioning of a transducer which cooperates with a spinning disk. The motor is feedback controlled for separate speed (seek) and positioning modes in which respectively the transducer is moved across the disk towards a different track and is held centered above that track. In order to offset the effect of a tilted axis of carriage movement, the control condition in the positioning mode representing a correct transducer position in which it is held by the motor, is continuously sampled and held during a period when the transducer is moved to another track to be applied as correction for the control moving the transducer towards another track. This correction signal is also used in the initial phases of holding the transducer above the newly selected track, until sampling and positioning control proper takes over.

Abstract: A servo system includes a servo loop incorporating an articulated mechanical arm or other controllable element, resolved motion rate control apparatus or other coordinate transformation apparatus, and an accommodation branch. The transfer characteristics may be readily adjusted to constrain the controllable element to accomplish a desired task, and the accommodation branch transfer characteristics may be readily modified to accomplish the performance of many different tasks without modifications to other portions of the system.

Abstract: A process and apparatus for producing sections of accurate weight or volume which includes the providing of a computer which receives various signals including the length, weight and density of a sheared off section and in response to such conditions varies the position of a length stop to insure that sections of accurate weight and volume are continuously obtained. The length stop mechanism is regulated by controlling the movement of a plurality of clamping devices which operate in conjunction with the axial movement of the material to be severed. The clamping devices are hydraulically operated.

Abstract: A servo system includes a servo loop incorporating an articulated mechanical arm or other controllable element, resolved motion rate control apparatus or other coordinate transformation apparatus, and an accommodation branch. The transfer characteristics may be readily adjusted to constrain the controllable element to accomplish a desired task, and the accommodation branch transfer characteristics may be readily modified to accomplish the performance of many different tasks without modifications to other portions of the system.

Abstract: A hybrid stepping motor unit includes a stepper-type primary motor and a secondary motor. The rotor shafts of the stepper-type primary motor and the secondary motor are connected to a common output shaft. The stepper-type primary motor is energized in response to an electrical command signal from an external source, such as a computer. When the stepper-type primary motor is energized, the stepper-type primary motor produces torque and attempts to drive the load combination of the interconnected rotor shafts, the common output shaft, and any mechanical load on the common output shaft, such as a machine tool component. This produces a reaction torque on the stepper-type primary motor. A transducer converts the reaction torque into an electrical control signal. The secondary motor is energized in response to the electrical control signal from the transducer.

Abstract: A synchronous rotary electric machine has a stationary superconducting D.C. field winding, a rotatable mechanical torque transmission shaft which carries normally conducting polyphase windings for providing a rotating field when A.C. currents circulate therein, and stationary auxiliary D.C. windings constructed to deliver a magnetic field. The currents in the auxiliary windings are adjusted for maintaining the torque and axial force tending to move the field winding under a predetermined value.