Abstract: In an angular velocity sensor including two oscillators, the oscillators are balanced in weight precisely, thus providing improved output characteristics. In the sensor, at least one of the two oscillators has a notch having a surface roughness of not higher than 2 ?m on an edge thereof.

Abstract: To reduce the outlay needed to calibrate a combination sensor having at least one rate-of-rotation sensor component and at least one acceleration sensor component, the combination sensor is subjected to a defined rotation about its rate-of-rotation sensitivity axis and, in the process, the combination sensor is positioned in such a way that the centrifugal force occurring in response to this rotation acts along its acceleration sensitivity axis.

Abstract: A sensor comprises a semiconductor pellet (10) including a working portion (11) adapted to undergo action of a force, a fixed portion (13) fixed on the sensor body, and a flexible portion (13) having flexibility formed therebetween, a working body (20) for transmitting an exterted force to the working portion, and detector means (60-63) for transforming a mechanical deformation produced in the semiconductor pellet to an electric signal to thereby detect a force exerted on the working body as an electric signal. A signal processing circuit is applied to the sensor. This circuit uses analog multipliers (101-109) and analog adders/subtracters (111-113), and has a function to cancel interference produced in different directions. Within the sensor, two portions (E3, E4-E8) located at positions opposite to each other and producing a displacement therebetween by action of a force are determined. By exerting a coulomb force between both the portions, the test of the sensor is carried out.

Abstract: A method of factory calibrating a police radar/laser detector including a controller, an accelerometer, and a memory, by manipulating the detector to rotate the accelerometer, measuring and feeding real time measurements from the accelerometer to a Least Squares Elliptical Fit algorithm executed by the controller, applying the Least Squares Elliptical Fit algorithm to the real time measurements to find the equation of an ellipse formed by the measurements, storing the coefficients of the ellipse in the memory. The coefficients are then recalled from the memory to thereby calibrate the accelerometer.

Abstract: The present invention describes a method to calibrate an angular measurement device using acceleration measurement device. The angular rate measurement device includes at least one angular measurement sensor, wherein the acceleration measurement device is able to distinguish the direction and strength of gravity. By performing the calibration method the scale factor(s) of the angular measurement device and the strength and direction of gravity can be obtained and/or corrected. An embodiment according to the method of the present invention describes optional use of a communication network to perform necessary evaluation and calculation steps at a remote device.

Abstract: Quadrature error occurs in vibrating gyroscopes because of manufacturing flaws that permit the sensing element (proof mass) to oscillate about an axis that is not orthogonal to the output axis. This creates an oscillation about the output axis that has a component of the sensing element's vibration acceleration. This output axis oscillation, which is in phase with the driven acceleration of the sensing element, is called quadrature torque since it is ninety degrees out of phase with the angular rate induced acceleration. In order to eliminate this output axis oscillation, the present invention generates sinusoidal forces on the dither mass by applying dc voltages on the dither mass pickoff electrodes. These forces create a counter dither motion about the output axis that cancels the output axis oscillation generated by the non-orthogonal dither axis.

Abstract: A method of factory calibrating a police radar/laser detector including a controller, an accelerometer, and a memory, by manipulating the detector to rotate the accelerometer, measuring and feeding real time measurements from the accelerometer to a Least Squares Elliptical Fit algorithm executed by the controller, applying the Least Squares Elliptical Fit algorithm to the real time measurements to find the equation of an ellipse formed by the measurements, storing the coefficients of the ellipse in the memory. The coefficients are then recalled from the memory to thereby calibrate the accelerometer.

Abstract: A test circuit and method provide testing of a capacitive type microsensor. The method includes applying a first signal having a first voltage potential to an input of a microsensor during a non-test operating mode. The method also includes applying a second voltage signal having a second voltage potential different than the first voltage potential during a test mode. The second voltage potential induces a net differential electrostatic force in the microsensor. The method further includes the steps of monitoring an output signal of the microsensor, comparing the output signal to an expected value when the microsensor is in the test mode, and determining if the microsensor is functioning properly as a function of the comparison.

Abstract: The present invention aims to present an angular velocity sensor having a self diagnosis function.

Abstract: In an implementation in rate gyro mode, the method comprises the steps of exciting the vibrating member by means of a combination of control signals comprising an amplitude control signal at the resonant frequency of the vibrating member or at a frequency twice the resonant frequency, a precession control signal at a frequency twice the resonant frequency, and a quadrature control signal at DC, at the resonant frequency, or at a frequency twice the resonant frequency. In free gyro mode, the method includes the steps of applying a combination of signals to common electrodes 5 and of applying said combination in alternation to main electrodes 5.1 and 5.2 and to secondary electrodes 7.1 and 7.2 interleaved between the main electrodes.

Abstract: A method of checking the functional reliability of a pressure sensor is described, the air pressure being detected inside a vehicle body part, the vehicle having at least one additional pressure sensor for detecting the air pressure.

Abstract: A speed sensor for a marine vessel includes a correction circuit to correct any sensor non-linearities so that the sensor produces an output with a pulse stream having a constant pulse rate, and reduces the pulse-to-pulse variations of the pulse stream. The circuit can standardize the pulse stream to have a frequency corresponding to a standard rate.

Abstract: In an angular velocity sensor including two oscillators, the oscillators are balanced in weight precisely, thus providing improved output characteristics. In the sensor, at least one of the two oscillators has a notch having a surface roughness of not higher than 2 &mgr;m on an edge thereof.

Abstract: A drive unit for calibrating an indicator/meter of a vehicle is provided in which a pointer in an indicator for a vehicle can point immediately after an ignition switch is turned ON, and the frequency of seeing motion of the pointer in an initializing operation by a car driver is reduced. A sensing mechanism (8a-3) is provided to sense an open/close operation of a door. Correspondingly to the sensing of the sensing mechanism (8a-3), a drive-start mechanism (8a-4) starts rotation of a stepping motor using a drive mechanism (8a-1) for initialization. The drive mechanism (8a-1) during initialization rotates the stepping motor to move a driven member toward a stopper.

Abstract: Inertial measurement systems for measuring accelerations and angular speeds are currently widely used in vehicles where they serve as sensors for safety devices and navigation systems. The required reliability and precision, however, can be obtained only with extremely accurate sensors and precise finishing. The invention therefore provides for a method according to which an inertial measurement system comprising economical, mass-produced sensors is first gauged overall in a testing device in one calibration operation. During gauging any offset, mounting position and scaling errors are detected as coefficients of coupling matrices of the sensors and converted into compensation values which are then used to improved the accuracy of the sensors' measurement values when the measurement system is in operation. The above method is suitable for inertial measurement systems in land, air and water craft.

Abstract: A system and method of calibrating a vehicle odometer (12) includes a controller (18) receiving signals from the odometer (12) indicative of movement of the vehicle (10) and a receiver (26) indicative of distance traveled. The controller (18) obtains information indicative of movement of the vehicle (10) in response to travel at a constant speed. The receiver (26) provides signals indicative of the distance traveled to the controller (18). The controller (18) determines an average number of signals relative to distance and compares the average number to a current number of signals relative to distance. Odometer calibration updates if the average and current number of signals relative to distance differs by a predetermined amount. The number of signals relative to the distance is only recorded when the vehicle (10) is traveling at a constant speed, eliminating aberrant data from odometer calibration.

Abstract: The present invention aims to present an angular velocity sensor having a self diagnosis function. An angular velocity sensor of the present invention includes a driving part for stably vibrating a driving part of a sensor element having a driver part and a detector part for detecting an angular velocity and detection means for detecting the angular velocity of the sensor element and obtains a self diagnosis signal for a malfunction by detecting a mechanical coupling signal obtained at the detection means.

Abstract: Bias error is reduced in a vibrating structure sensor having primary and secondary pick-offs separated by a fixed angular amount (45°) with respect to the vibrating structure by summing a proportion of the primary pick-off output signal into the secondary pick-off output signal or subtracting a proportion of the primary pick-off output signal from the secondary pick-off output signal effectively to reduce or increase the angular separation of the secondary pick-off from the primary driver by an amount sufficient to set the rate output signal from the vibrating structure to zero and thereby minimize bias error.

Abstract: An acceleration measuring apparatus capable of calibrating its output with a zero-point in the state of no acceleration applied as well as sensitivity is disclosed. An acceleration measuring apparatus an acceleration sensor that detects each component of an acceleration and creates an output based on each of the detected component in each direction of at least two mutually perpendicular axes of orthogonal coordinates for acceleration sensor; a holding means that holds the acceleration sensor at at least two different positions, in which the acceleration sensor axes at one position each is at a different angle with the gravitational acceleration direction from the other; and a processing circuit.

Abstract: An acceleration detection device for detecting an acceleration applied in a certain direction based on detection signals corresponding to the acceleration, is provided with a waveform detection part detecting waveforms of the detection signals and an acceleration determination part determining whether to make valid or invalid the acceleration based on the waveforms detected in the waveform detection part.

Abstract: The present invention provides cavitation detection systems and methods employing a classifier for detecting, diagnosing and/or classifying cavitation in a pumping system. The classifier can be integral to tie cavitation detection system and/or operatively coupled to the cavitation system via a controller, diagnostic device and/or computer. Parameters such as flow, pressure and motor speed arc measured and/or estimated, and then provided to a classifier system Such systems include Bayesian, Fuzzy Set, nonlinear regression, neural networks and other training systems, for example The classifier system provides a signal indicative of the existence and extent of cavitation. An exemplary classification system is presented that delineates cavitation extent into one or more of the following categories: 0 (no cavitation), 1 (incipient cavitation), 2 (medium cavitation), 3 (fill cavitation) and 4 (surging cavitation).

Abstract: A method for determining a scale factor of an accelerometer. The scale factor is used to precisely convert the electrical output of the accelerometer into units of acceleration. The accelerometer to be calibrated is mounted on a turntable mechanism. The turntable is configured so that the axis of rotation of the turntable is tilted with respect to the local gravity vector. The turntable is then spun around the axis of rotation at an angular velocity, such that the accelerometer experiences a time varying component of the local gravity vector. The output of the accelerometer is logged as the accelerometer experiences the time varying component of the local gravity vector. The logged output of the accelerometer is compared to a predicted output of the accelerometer, wherein the predicted output is based on the tilt angle of the turntable and the angular velocity of the turntable and on the value of gravitational acceleration at the location of calibration.

Abstract: In an exemplary embodiment, a MEMS sensor using a passive temperature compensation technique may provide an uncompensated sense output. Additionally, a circuit coupled to the MEMS sensor may include a diode having a voltage drop. A compensated sense output may be formed by combining the uncompensated sense output with a diode output that is proportional to the voltage drop across the diode.

Abstract: Quadrature error occurs in vibrating gyroscopes because of manufacturing flaws that permit the sensing element (proof mass) to oscillate about an axis that is not orthogonal to the output axis. This creates an oscillation about the output axis that has a component of the sensing element's vibration acceleration. This output axis oscillation, which is in phase with the driven acceleration of the sensing element, is called quadrature torque since it is ninety degrees out of phase with the angular rate induced acceleration. In order to eliminate this output axis oscillation, the present invention generates sinusoidal forces on the dither mass by applying dc voltages on the dither mass pickoff electrodes. These forces create a counter dither motion about the output axis that cancels the output axis oscillation generated by the non-orthogonal dither axis.

Abstract: Disclosed is a malfunction method and system for an output shaft rpm sensor of a transmission. The method comprises the steps of: detecting output shaft rpm of a transmission by the output shaft rpm sensor, and detecting vehicle speed by a vehicle speed sensor; determining whether malfunction conditions, which indicate a malfunction in the output shaft rpm sensor, are satisfied based on the output shaft rpm and the vehicle speed; performing stand-by for a predetermined stand-by time if the malfunction conditions are satisfied; determining whether there is a malfunction in the output shaft rpm sensor using the detected output shaft rpm; and generating malfunction codes if it is determined that there is a malfunction in the output shaft rpm sensor. The system comprises a vehicle state detector for performing detection of various drive states and operations of elements of a vehicle, and outputting corresponding signals, and an ECU for performing the method.

Abstract: To reduce the outlay needed to calibrate a combination sensor having at least one rate-of-rotation sensor component and at least one acceleration sensor component, the combination sensor is subjected to a defined rotation about its rate-of-rotation sensitivity axis and, in the process, the combination sensor is positioned in such a way that the centrifugal force occurring in response to this rotation acts along its acceleration sensitivity axis.

Abstract: A method is described for balancing the phase-locked loop (10) of an electronic analyzing device (8) which analyzes the output signal of a sensor device (3), a yaw rate sensor in particular using the Coriolis effect having an oscillating mass which undergoes a deflection (&Dgr;x) under the effect of an external yaw rate on the sensor device and the output signal representing a yaw rate signal, the electronic analyzing device (8) having in addition to the phase-locked loop (10), a control loop (20), a quadrature control loop in particular, and the control loop is provided with a controller (22) having an input and an output as well as with a modulator or mixer (23) having an input which has a first electrical connection with the output of the controller (22).

Abstract: The present invention describes a method to calibrate an angular measurement device using acceleration measurement device. The angular rate measurement device includes at least one angular measurement sensor, wherein the acceleration measurement device is able to distinguish the direction and strength of gravity. By performing the calibration method the scale factor(s) of the angular measurement device and the strength and direction of gravity can be obtained and/or corrected. An embodiment according to the method of the present invention describes optional use of a communication network to perform necessary evaluation and calculation steps at a remote device.

Abstract: A method is provided to process system test data to determine certification parameters of the system based on the test data. For a torpedo launch system, the velocity data is generated by a Pressure/Velocity/Displacement housing interfaced with a computer based data acquisition system and known launch system and test parameters, such as sample rate, muzzle exit length, time of acquisition, decimation factor and low pass cutoff frequency are provided as inputs. The method forces assigns a value of zero to any data less than a predetermined threshold in order to eliminate non-zero levels contributed by ambient noise. The method then passes the data through a filter chosen to agree with hand fit smoothing methods, so as to obtain a smoothed velocity profile. The smoothed data is processed to obtain and display an acceleration profile and a displacement profile, as well as data points for peak acceleration, time at peak, acceleration pulse width, muzzle exit velocity and time at exit.

Abstract: The invention provides a method and system for calibrating an instrument pointer driven by an electric motor against a mechanical stop without using feedback control. According to the invention, the system for calibrating said instrument pointer comprises a pointer (8) engageable with the electric motor (2) including an intermediate gear (3) for driving the pointer (8). A stop means (5) is positioned at a desired reference point where, in a first powered state, the motor (2) is accelerated at a maximum torque for a first predetermined radial distance to move said pointer (8) towards a position whereat said stop means (5) is engaged. The motor (2) is then re-accelerated at a reduced torque for a second predetermined radial distance, whereby the pointer (3) is caused to be moved and held against the stop means (5).

Abstract: Dynamic balancing reduces quadrature bias in microfabricated vibrating instruments such as tuning fork gyros so that a purity of motion is achieved in the absence of any angular rate input. Balancing is achieved by ablating (74) or depositing (72) onto support structure (62) for a tuning fork gyroscope rather than the proof mass (60) itself by melting and moving material on a tuning fork beam (62). Such adjusting is advantageously done during actual operation of the gyro by laser beam application through an encapsulating transparent cover which can be either part of the chip die or an external package.

Abstract: A control system for a plurality of motor vehicle chassis subsystems comprises a reference model, a state estimator, a feedforward controller, and a feedback controller. The reference model computes desired states of the chassis subsystems. The state estimator estimates actual states of the vehicle. The feedforward controller computes a control value based on input from the reference model, and the feedback controller computes a control value by comparing the estimates of actual states with the desired states.

Abstract: The invention relates to a calibration method for a system with at least two accelerometers (5), comprising the steps of arranging said accelerometers fixed on a vehicle (1), connecting said accelerometers (5) to a control unit and providing said vehicle (1) on a reference plane (11). The reference plane (11) has a known propagation angle to be used as a reference relative to which an offset value of each accelerometer (5) is established. Said offset value of each accelerometer is stored in said control unit. The invention also relates to a calibrated accelerometer system and a vehicle (1) provided with said system.

Abstract: An electronic speedometer calibration device includes a microcontroller and an entry device. The microcontroller receives an electrical speed signal from the speed sensor. The microcontroller is instructed to change the frequency of the electrical speed signal by some multiplication factor. The multiplication factor may be entered through a keypad, a computer download, or through any other suitable device. The multiplication factor is preferably shown on a display device. The multiplication factor may be greater than or less than one. The microcontroller will output an electrical speed signal to the electronic speedometer with a frequency which has been modified by the multiplication factor. The speedometer will display the corrected speed. A second embodiment of the electronic speedometer calibration device includes a digital frequency multiplier and a digital frequency divider.

Abstract: A meter such as a speedometer for use in an automobile instrument panel includes a pointer driven by a stepping motor. A pulse voltage having a wider pulse width is supplied to the stepping motor to obtain a higher induced voltage to be compared with a threshold voltage for detecting the pointer-zero-position. After the pointer-zero-position is detected, the stepping motor is driven by a pulse voltage having a narrower pulse width to obtain a quicker response of the pointer. In this manner, the pointer-zero-position is accurately adjusted without sacrificing the quick response of the meter pointer.

Abstract: Inertial rate sensor and method in which a drive signal consisting initially of a square wave and thereafter a sine wave is applied to a vibratory rate sensing element, a pickup circuit is coupled to the rate sensing element for providing an output signal corresponding to movement of the rate sensing element, the magnitude of the drive signals is adjusted to set a scale factor which determines the sensitivity to movement of the rate sensing element, and a signal in the drive circuit is monitored to detect a failure.

Abstract: A sensor comprises a semiconductor pellet (10) including a working portion (11) adapted to undergo action of a force, a fixed portion (13) fixed on the sensor body, and a flexible portion (13) having flexibility formed therebetween, a working body (20) for transmitting an exterted force to the working portion, and detector means (60-63) for transforming a mechanical deformation produced in the semiconductor pellet to an electric signal to thereby detect a force exerted on the working body as an electric signal. A signal processing circuit is applied to the sensor. This. circuit uses analog multipliers (101-109) and analog adders/subtracters (111-113), and has a function to cancel interference produced in different directions. Within the sensor, two portions (E3, E4-E8) located at positions opposite to each other and producing a displacement therebetween by action of a force are determined. By exerting a coulomb force between both the portions, the test of the sensor is carried out.

Abstract: A method for visualizing and indicating characteristics of vibration measurement data for a rotating or vibrating object. Specific components are removed from the measurement data or are minimized therein. After removing or minimizing the specific component, the measurement data is indicated in a Campbell diagram.

Abstract: An apparatus for determining a rotation rate has an oscillatory body 11 on which a plurality of electromechanical converters A, A′, B, B′, C, C′, D, D′ are mounted. At least a first converter A, A′ is caused to oscillate mechanically by an electric driver signal UF,O generated in a first circuit arrangement 12. Further, at least a second converter D, D′ is caused to oscillate mechanically by an electric damping signal UF, D generated in a second circuit arrangement 13. At least a third converter C, C′ emits an electric sensor damping signal US, D which corresponds to the oscillation of the body 11 in the location where the at least third converter D, D′ is mounted. The damping sensor signal US, D is fed back to the input of the second circuit arrangement 13. A voltage divider 31 is provided, by means of which the signal UF, D generated in the second circuit arrangement 13 can be reduced.

Abstract: A method for calibrating an orthogonal sensor suite includes the steps of imparting on the sensor suite a series of known accelerations at orientations known relative to each other, while recording readings from the sensors from each acceleration at each orientation. This data is used to create a transformation matrix which removes offsets from each sensor and removes any cross-coupling of the sensors.

Abstract: A coordinate measuring machine (CMM) carries a probe and is controlled by a controller to drive the probe to take measurements on a workpiece. In order to reduce the effects of acceleration-induced deflections of the probe on the measurements made by the machine, accelerometers are provided to measure the accelerations of the probe and to produce signals indicative thereof. The acceleration signals (45) are passed to the controller (FIG. 2) where they are integrated (46) and filtered (48) before being passed as velocity signals (49) to a summing junction (50) from which they are fed to a velocity feedback control loop[ (34, 35, 36, 37) which reduces any changes in the velocity (and hence deflection) of the probe due to the accelerations.

Abstract: A method for testing a Coriolis transducer having a mass adapted vibrate along a vibratory direction in a resonant structure and undergo a displacement along a sensitive axis, perpendicular to the vibration, in response to an angular rate about a mutually perpendicular rate sensing axis. In the absence of an angular rate about the rate sensing axis, forces, FTEST VIBRATORY and FTEST SENSITIVE, are applied on the mass along the direction of vibration and along the sensitive axis, respectively, in a predetermined ratio, N. The output VOUT TEST of the transducer is measured in response to the forces, FTEST VIBRATORY and FTEST SENSITIVE. With such method, a known test input angular rate &OHgr;IN TEST SIM is simulated, such rate, &OHgr;IN TEST SIM, being a known function of a measured characteristic frequency, for example the resonant bandwidth, BW, of the resonant structure.

Abstract: An apparatus is provided for testing and calibrating a sensor of a complex machine tool while the sensor is completely separated from the machine tool. The sensor, which is typically a gear tooth sensor, can typically comprise a sensing head and a printed circuit board which contains an electronic circuit designed to manipulate signals received from the sensing head. A movable target, such as a gear tooth wheel, is driven by an air motor, and the sensing head is attached to a support structure with the operative surface of the sensing head being located a preselected distance from the discontinuities of the target simulator. A signal receiver, such as oscilloscope is easily connected in signal communication with the printed circuit board so that an operator can adjust the amplitude and offset of the signals as the target simulator is operated.

Abstract: An eccentric error corrector for a rotary-type acceleration generating apparatus. The eccentric error corrector includes a large-diameter turntable and a small-diameter turntable. The large-diameter turntable is rotated by a first servo motor. The small-diameter turntable is mounted on the outer periphery portion of the large-diameter turntable and rotatable by a second servo motor, in which an acceleration sensor is attachable to the small-diameter turntable. The eccentric error corrector includes a DC-component remover removing only the DC component from an output signal of the acceleration sensor attached on the small-diameter turntable.

Abstract: The subject invention is directed to methods, processes and decisions on test outcomes for testing for faulty, therefor dangerous, performance of zero speed indicators that are used to control the opening of barriers guarding moving machine components. The indicators may be tested by removing them from the components during operation without shutting down production or in certain situations the indicators may be tested during the run down phase of the components caused by machine stop initiations. The tests allow to anticipate and hence prevent hazardous opening of barriers due to a faulty zero speed indication. Additionally, the invention is directed to testing of the insertion of motion interference devices in conjunction with zero speed indicators, both of which must perform correctly in order to permit the unlocking and opening of the protective barrier. There are included various exemplary devices for effecting the testing function.

Abstract: When a person wearing the wristwatch device (11) on his or her dominant arm has struck a blow, an acceleration sensor (12) senses acceleration at regular intervals of time, extracts accelerations x1 to x20 sensed at 20 points in front of the hit point H at which the sensed acceleration changes from positive to negative, and stores them in a RAM (20). The impulse force is calculated by multiplying the accelerations x1 to x20 at the 20 points in front of the hit point H by the weighting coefficients determined on the basis of the accelerations sensed in a trial performance and the actually measured impulse force and stored in a ROM (19). Therefore, the impulse force can be estimated accurately without actually striking a secured object.

Abstract: The subject invention is directed to methods, processes and decisions on test outcomes for testing for faulty, therefor dangerous, performance of zero speed indicators that are used to control the opening of barriers guarding moving machine components. The indicators may be tested by removing them from the components during operation without shutting down production or in certain situations the indicators may be tested during the run down phase of the components caused by machine stop initiations. The tests allow to anticipate and hence prevent hazardous opening of barriers due to a faulty zero speed indication. Additionally, the invention is directed to testing of the insertion of motion interference devices in conjunction with zero speed indicators, both of which must perform correctly in order to permit the unlocking and opening of the protective barrier. There are included various exemplary devices for effecting the testing function.

Abstract: An angular rate sensor comprises a determination circuit (30) for inputting an output signal of a full-wave rectifier circuit (22) and an output signal after amplified by a charge amplifier (25), and making a determination of abnormality, and an output clamping circuit (32) activated by an output signal of the determination circuit (30), if it makes a determination of abnormality, for clamping an output signal of a sensor output terminal at a level close to a power supply voltage or a grounding voltage.

Abstract: Disclosed is a method of correcting quadrature error in a dynamically decoupled micro-gyro (100, 200) having a drive mass (110, 210) that is vibrated relative to a drive axis (Y, Z) and a sense mass (111, 211) that responds to the drive mass (110, 210) in the presence of an angular rate and associated coriolis force by vibrating relative to a sense axis (X, Y). The method includes the steps of providing a first static force element (121, 221) for applying a first steady-state force to a first region of the drive mass (110, 210); providing a second static force element (122, 222) for applying a second steady-state force to a second region of the drive mass (210), and applying a corrective steady-state force to the drive mass (110, 210) with the first and second static force elements (121, 122; 221, 222), the corrective steady-state force making the drive axis (Y, Z) of the drive mass (110, 210) orthogonal to the sense axis (X, Y) of the sense mass (111, 211).

Abstract: A meter such as a speedometer for use in an automobile instrument panel includes a pointer driven by a stepping motor. A pulse voltage having a wider pulse width is supplied to the stepping motor to obtain a higher induced voltage to be compared with a threshold voltage for detecting the pointer-zero-position. After the pointer-zero-position is detected, the stepping motor is driven by a pulse voltage having a narrower pulse width to obtain a quicker response of the pointer. In this manner, the pointer-zero-position is accurately adjusted without sacrificing the quick response of the meter pointer.