Abstract: Methods, apparatus, systems and articles of manufacture to increase resolver-to-digital converter accuracy are disclosed.

Abstract: In a position detection device of a type that omits a secondary coil, various inconveniences arising from the use of a voltage-dividing resistance (fixed resistor) are eliminated. At least two pairs of coils are provided. A magnetism-responsive member are placed so as to effect relative displacement in relation to the coils, the relative position of the member in relation to the coils varies with a position of a detection object, and impedance of each coil is varied with the relative position. The impedance changes of two coils constituting each one of coil pairs present characteristics of mutually opposite phase characteristics. For each coil pair, the two coils constituting the pair are connected in series with each other, and from a connection point thereof, a voltage-divided output voltage according to the impedance of the two coils is taken out as a detection output signal for the pair.

Abstract: A resolver to digital converter system comprises a resolver and a controller. The resolver has a reference winding attached to a rotor, and first and second output windings attached to a stator and coupled to the reference winding. The reference winding is configured to be driven with a reference AC signal having a known frequency and induces first and second output signals from the first and second output windings in response to the reference AC signal. The controller circuit is configured to compare the first and second output signals to first and second linear signals respectively, ascertain first and second time intervals between first and second determined start time points and first and second stop time points where magnitudes of the first and second output signals are substantially equal to magnitudes of the first and second linear signals, respectfully. The controller circuit is further configured to calculate a rotating angle of the resolver based on the first and second time intervals.

Abstract: A method for sensing a position of a lead wire during winding of a wire on a coil form to form a precision coil is provided. The method includes acquiring data representative of at least a portion of the precision coil, identifying portions of the acquired data that represent the wire in the precision coil, and determining a position of the lead wire on the coil form from the identified portions of the acquired data.

Abstract: A method for detecting a position of a movable element of a drive apparatus by means of a position detection apparatus comprising at least one field coil and at least one secondary coil associated with the field coil, wherein an electrical excitation pulse is applied to the field coil in order to induce an electrical voltage in the secondary coil, a secondary coil voltage is measured and the position of the movable element is determined on the basis of the measured secondary coil voltage. The invention also relates to a position detection apparatus and/or a drive apparatus.

Abstract: Apparatus for controlling the voltage supplied to a load, comprising: a multi-phase transformer having a primary and a secondary winding for each phase, each secondary being connected in series between an input line and an output directed to the load; and the primary is configurable by switches such that the phase of the voltage of the secondary is different from the line to which it is connected by a phase different from 0 and 180 degrees.

Abstract: A method for providing electrical energy to an actuator is disclosed. In at least one embodiment, the method includes having a first voltage (UBUS) from a data bus; ii) converting the electric current to a current having a second voltage that is higher than the first voltage; iii) storing electrical energy of the second electric current; and discharging the stored electrical energy to an actuator. A device is also disclosed for providing electrical energy to an actuator.

Abstract: A system compatible for different types of signals relates to a motor includes a differential amplifier, a comparator, and a transmitting device. The differential amplifier is configured to receive one of a differential digital pulse signals pair and a differential analog signals pair. The differential digital pulse signals pair is converted to a first digital signal, and the differential analog signals pair is converted to an analog signal by the differential amplifier. The comparator is configured to convert the analog signal into a second digital signal. The first digital signal is received and outputted by the comparator. The transmitting device is configured to convert a data signals pair to a binary code, and convert differential reference digital signals pairs to reference digital signals. The reference digital signals, the first and second digital signals are received by an external computing device.

Abstract: The invention relates to a device and a method for estimating the rotational speed ? of an electric motor when freewheeling, the method being carried out in a variable speed drive for controlling the motor by generating reference alternating voltages Va, Vb. The method comprises a step for measuring the measured flux and torque currents Id and Iq of the motor in an orthogonal two-phase marker d, q, a step for determining said reference voltages Va, Vb, by carrying out a current regulation on the basis of said measured currents, and on the basis of zero reference currents Idref and Iqref in said marker d, q, and a step for calculating the rotational speed ? by evaluating the angle of rotation of the voltage vector, the components of which are said voltages Va, Vb in a fixed orthogonal two-phase marker a, b.

Abstract: A system compatible for different types of signals relates to a motor includes a differential amplifier, a comparator, and a transmitting device. The differential amplifier is configured to receive one of a differential digital pulse signals pair and a differential analog signals pair. The differential digital pulse signals pair is converted to a first digital signal, and the differential analog signals pair is converted to an analog signal by the differential amplifier. The comparator is configured to convert the analog signal into a second digital signal. The first digital signal is received and outputted by the comparator. The transmitting device is configured to convert a data signals pair to a binary code, and convert differential reference digital signals pairs to reference digital signals. The reference digital signals, the first and second digital signals are received by an external computing device.

Abstract: A control apparatus for a machine that can be operated at high precision in a stable control state is provided by driving a movable body with control parameters suited to the mechanical state. A control parameter calculation circuit is provided to obtain control parameters for a drive apparatus control circuit for driving actuators in accordance with the conditions of actuator rotational velocity, the orientation of the movable body, and the position of the movable body, and a control parameter K for the drive apparatus control circuit is varied.

Abstract: A magnetic flux produced by the current of a motor is detected by means of a Hall element, and an infinitesimal current proportional to the actual current of the motor is outputted. The outputted infinitesimal current is run through a resistor, and a potential difference across the resistor is detected by a ?? modulator circuit. The motor is subjected to feedback control based on the potential difference detected by the ?? modulator circuit.

Abstract: In an industrial robot having a plurality of arms, each arm is coupled with other elements, such as a mounting base, another arm, a robotic hand, and revolved by a motion of the revolvable joint. The revolvable joint has a rotary electric connecting structure such as a slip ring or a rotary transformer which can be rotated endlessly. Electric powers for driving motors by which the arms are revolved and control signals for controlling the driving of the motors are supplied or transmitted through the rotary electric connecting structure, so that the arms can be rotated endlessly without twisting or breaking of electric cables.

Abstract: The invention relates to an arrangement for automatically influencing a mains supply. A voltage transformer is provided as a pilot transformer which detects the real value of the voltage which is to be adjusted and which transmits said value to a motor drive via an individual electric measuring circuit in which means are provided for comparing said real value to a set point value and for producing an adjustment command which is dependent upon said comparison. The invention also relates to a correspondingly equipped motor drive provided with an additional control module which directly actuates an electric motor independently from the direction of rotation when required. Said electric motor drives a step-switching mechanism on the variable-voltage transformer, whereby the voltage is adjusted, thereby influencing the mains supply.

Abstract: A current transducer includes a current transformer in which the conductor carrying the current to be monitored constitutes the primary. The transformer secondary is wound on a toroidal core. The transformer is operated below its cut-off frequency such that the output from the secondary is proportional to the differential of the current in the primary. The secondary output is integrated by an integrator to provide a measure of current in the primary and the integrator is initialized at predetermined intervals. A current measuring device for an electric machine, for example a reluctance machine, includes at least one of the current transducers.

Abstract: A position control and monitoring circuitry is provided for an electric motor having a plurality of coils and a movable element. A drive circuit generates a square wave drive signal of variable mark/space ratio to drive the coils to position the movable element. A monitoring circuit modulates square wave transitions at a sub-harmnonic of the drive signal frequency and generates a monitoring signal for injection into the coils. A sensor senses the monitoring signal from the coils to determine the position of the movable element. A difference circuit drives the drive circuit with a difference between an input signal and an output signal of the sensor.

Abstract: A displacement detector for enabling a precise detection of a displaced quantity of the core. The displacement detector is provided with a displaceable core, a detecting coil the inductance of which varies in response to a displaced quantity and a reference resistor, wherein a transient response voltage in case of a pulse voltage being applied to the inductance and the reference resistor is detected to enable detection of the absolute value of the inductance and thereby the change in the inductance which corresponds to the displaced quantity is detected independently of the peak value or the frequency of the pulse voltage. The displacement detector is preferably used in a torque sensor for an electric powered steering system, wherein the core of the displacement detector is formed of nonmagnetic metal material, the structure is simple, and a sensitive detection of a displaced quantity of the steering torque is possible.

Abstract: Two A.C. output signals amplitude-modulated in accordance with two function values (sine and cosine) differing from each other in correspondence to a position-to-be-detected are received from a position sensor such as a resolver. By performing an addition or subtraction between a signal derived by shifting the electric phase of one of the received A.C. output signals by a predetermined angle, and the other received signal, two electric A.C. signals (sin(.omega.t .+-.d.+-..theta.), sin(.omega.t.+-.d-.theta.)) are electrically synthesized which have electric phase angles (.theta.) corresponding to the position-to-be-detected and are phase-shifted in opposite directions. ".+-.d" here represents phase variation error caused by factors, other than the position-to-be-detected, such as temperature change. In the synthesized two signals, the phase variation errors (.+-.d) appear in the same direction, while the phase differences (.theta.

Abstract: A waveform generator for a resolver transducer or the like is described. Such generator forms two 3-level waveforms which approximate sinusoidal waveforms for the excitation and/or output detection of such a resolver. Each of the sinusoidal waveforms is formed by combining a pair of digitally programmed bi-state signals which have their phases shifted relative to one another by an amount proportional to an angular input variable. The result is that the amplitude of these sinusoidal waveforms which are formed are representative of the sine and cosine of such variable.

Abstract: A method and system for exploiting the signals of linear inductive sensors, which system is adaptable for different sensor structures. The system is formed of a linear inductive displacement sensor provided with a primary coil and two identical symmetrical secondary coils which are in series and in antiphase. A mobile core and an alternative voltage source are mounted between the terminals of the primary coil wherein the amplitude of the voltage at the primary coil terminals is greater than the maximum amplitude of the voltage that can be taken at the secondary coil terminals. The method has the steps of forming the sum of the two alternative voltages present at the primary and secondary coils. These voltages are rectified by means of full wave rectifying and deriving the difference between the sum of recitified voltages. A continuous means valve corresponding to the difference is also derived.

Abstract: A linear, analog, synchro control differential transmitter for implementing he common synchro CDX function whereby a scaled linear analog voltage is used as input instead of a mechanical shaft angular displacement. Alternate synchro functions of CT and CX that the invention implements are also disclosed.

Abstract: For enabling a resolver to have absolute position sensing over a wide displacement range while still obtaining the resolution, accuracy and precision obtainable by operation in an incremental mode, the resolver is provided with a number of terminals for providing offset pitch phase indications as a function of position. A microcomputer is programmed to execute a decoding procedure for reading the offset pitch phase indications and from them computing the absolute position. This method is applicable to linear as well as rotary position sensing. By using multiplexing, digital signal processing and large-scale circuit integration for interfacing the resolver to the microcomputer, the method can achieve absolute position sensing with high reliability and low cost. The offset pitch phase indications are readily provided by inductive coupling between a multiplicity of windings, including a set of offset pitch windings connected to the terminals.

Abstract: An apparatus for generating phase modulated angular positional signals in digital form. A phase tracking loop receives a phase modulated signal from the rotor of a resolver whose stator windings are excited in quadrature. The phase output of the resolver is proportional to the angular displacement of the rotor. Signals for exciting the stator windings of the resolver are applied in phase quadrature to a phase detector to develop an analog error signal when combined with the rotor output signal. The analog phase error signal provides an output indicative of the angular displacement of the rotor. The error signal is applied to a voltage controlled oscillator, converted to digital form, and combined with the excitation signals in a closed loop to force the error signal to a null, whereupon the indicated digital output angle is in coincidence with the angular displacement of the rotor shaft.

Abstract: Phase information in a multiple-coil indictive displacement sensor is retained by summing the excitation signal with each of the secondary signals to provide augmented secondary signals which may then be converted to a digital format. A signal processor may then be employed to extract both the magnitude and phase information from the augmented secondary signals by subtracting the magnitude of the primary excitation signal from each of the augmented secondary signals. The resulting signals retain both phase and magnitude information.

Abstract: An azimuth data stabilization system for a shipborne mechanically scanned arch-track system. A unitary package is provided mounted on the roll and pitch stabilized search-track system platform. The package includes a gyro stabilized turntable with the axis of rotation thereof aligned parallel to the axis of rotation of the search-track system. A gyro-torquer loop is provided to inertially stabilize the turntable and a synchro or resolver chain is provided to align the turntable with an azimuth reference. Corrected ships heading signals, derived from the angular position of the turntable, are either coupled directly to appropriate data processing equipment or are combined differentially as compensating signals with the azimuth data signals from the search-track system to provide a true azimuth data output.

Abstract: A control for a profiling machining tool, and a method for controlling such a tool. The machine tool includes a sensing head which moves along a template or pattern to produce a signal that causes motors relatively to shift a cutting tool and a workpiece so as to duplicate in the workpiece the profile of the template or pattern. Two sinusoidal signals are generated as a consequence of stylus deflection along orthogonal axes. They are combined to form a single sinusoidal signal which is then variously processed to produce an error signal which causes the motors to operate in directions which tend to reduce the error signal, and to cause the stylus automatically to move along the profile while doing so.

Abstract: A numerical control system is provided for a table having a relatively stationary member, a relatively movable member and a position transducer, such as an inductosyn, operatively positioned between them. The numerical control system comprises a high frequency clock which generates a pair of sinusoidal waves to the inductosyn at a lower frequency and the phase of the output signal from the inductosyn is representative of the position of the movable and stationary members. A direction and speed control circuit generates an output signal the frequency and polarity of which is indicative of the desired speed and direction of movement of the movable member, respectively, and this output signal is combined with the high frequency signal from the clock by a signal combiner.

Abstract: A solid state synchro torque receiver driver that uses unfiltered AC as the power source and push-pull regulating transistors operating in the linear mode to drive the torque receiver stator loads. A feedback amplifier compares the push-pull outputted AC signal against an inputted AC data reference (i.e. the desired stator excitation amplitude) and thus closes the loop forcing the output to follow the input. The synchro torque receiver operates in a closed loop and thus has realizable potential of near infinite resolution and high accuracy.

Abstract: A tracer unit for use with measuring machines is described.The main feature of this tracer unit is to comprise a plurality of tracer tools, each of which is provided with a rod arranged to come into contact with a surface to be scanned, a movable body connected to said rod, a fixed body, first means which supply a first signal either when said movable body leaves the position of equilibrium relative to said fixed body or when said movable body passes through a determined position relative to said fixed body, and second means arranged to indicate from which of the various tracer tools said first signal is originated.

Abstract: A phase-sensitive transducer apparatus comprises first and second relatively movable members, the first relatively movable member having a plurality of windings and the second relatively movable member having a winding. Means are included for applying a first input signal to one of the windings of the first relatively movable member and a second input signal to another of the windings of the first relatively movable member. An output signal is developed on the winding of the second relatively movable member. The first and second input signals are sinusoidal in nature of substantially identical frequency and peak amplitude and are phase-displaced by a predetermined amount, and the output signal is substantially constant in peak amplitude and variable in phase during relative movement of the first and second relatively movable members.

Abstract: A remote magnetic instrument, such as a compass, and a heading indicator, such as a heading gyro, are time shared in a dual channel gyro slaving amplifier with slaving and boot strap circuitry. The amplifier is a two function electronic device wherein the slaving circuit accepts heading error data from a heading gyro and provides separate channels of amplified information to slave drive the heading gyro. The second function of the amplifier is an electronic boot strap circuit to extract information from the heading gyro to drive a remote magnetic instrument. Each of the two functions shares equal time by operation of a time sharing switch with a timing signal provided from a ripple counter. The amplified information providing during the first function of the amplifier is a slaving signal representing heading correction generated by the slaving circuit responding to a heading error signal from the heading indicator.

Abstract: A system for sensing the air gap between a cutting tool and a work piece mounted on a machine for the purpose of controlling the traverse feed rate of the machine as contiguity approaches. A drive coil is mounted on the machine. A search coil surrounds the cutting tool in proximity to the air gap and is mutually coupled (M.sub.1) to the drive coil. A mutual inductor has first and second coils arranged so that their mutual inductance M.sub.2 is variable; these coils are connected in common at one end to a variable inductionless resistor r. The first coil is connected series aiding with the drive coil, while the second coil is connected in series opposition with the search coil. An a.c. source is connected across the drive coil, first coil and inductionless resistor. The induced voltage across the series combination of search coil, second coil, and inductionless resistor provides an output which is initially nulled by adjusting M.sub.2 and r for a selected datum displacement between cutting tool and work piece.

Abstract: A mechanical-electrical transducer for the simultaneous contact-free and reaction free determination of a plurality of translatory and/or rotary components of the motion or position of an object coupled to the transducer, with a computer circuit which generates signals corresponding in sign and magnitude to the components of the deviation of the object from a predetermined initial position.