Abstract: A building monitoring system includes a sensor configured to sense a condition and collect sensor data related to the sensed condition. The building monitoring system also includes a server configured to receive the sensor data. The server is configured to analyze the sensor data to detect an undesirable condition and a threat from the undesirable condition within a structure and automatically issue a notification upon detection of the undesirable condition and the threat.

Abstract: Aspects of the present disclosure include a sensor configured to store in memory indications of sensor use information and formulas or indications of formulas for determining the useful life of a sensor from the indications of sensor use information. A monitor connected to the sensor monitors sensor use and stores indications of the use on sensor memory. The monitor and/or sensor compute the useful life of the sensor from the indications of use and the formulas. When the useful life of the sensor is reached, an indication is given to replace the sensor.

Abstract: A sensor processing system includes a plurality of reduction circuits. The plurality of reduction circuits correspond to a plurality of sensors on a one-to-one basis. Each of the plurality of reduction circuits is electrically connected to an output terminal of a corresponding one of the plurality of sensors to reduce a low-frequency component of a sensor output of the corresponding one of the plurality of sensors.

Abstract: A brain-computer interface device includes a plurality of pre-amplifiers are configured to amplify physiological signals corresponding to channels to output amplified signals; a multiplexer is configured to output, according to a control signal and a clock signal, the amplified signals; an analog-to-digital converter is configured to convert, according to the clock signal including clocks, the output of the multiplexer into a digital signal including a plurality of digital values corresponding to the clocks, wherein each of the digital values includes bit values; a memory is configured to store the digital signal; and a processor s configured to: add a header corresponding to one channel to each of the digital values according to the clock signal; and delete bit values of higher bits of each of the digital values corresponding to the same channel that are the same as those of a previous digital value, to output a compressed signal.

Abstract: A system includes a conditioning circuit, resistors connected to pins of the conditioning circuit, and measurement sensors connected to pins of the conditioning circuit. The conditioning circuit is configured to determine resistance values of the resistors and to determine a set of addresses for the measurement sensors based upon a combination of the resistance values of the resistors.

Abstract: A pointer is rotational relative to the screen. A driver unit rotates the pointer. An imaging device detects an image of the pointer sends a signal of the image. A controller receives the signal of the image from the imaging device. The screen indicates a graphic. The controller modifies the graphic according to the signal of the image.

Abstract: A controlling unit and a method of correcting an actual limit value of a sensor signal is described, wherein above or below the limit value a specific state of the sensor is recognized, the method including the steps of determining a new limit value of the sensor, determining a stability criteria to decide whether the actual limit value is corrected with said new limit value and approaching the actual limit value to the new limit value when the conditions are fulfilled to correct the actual limit value for said sensor.

Abstract: An offset cancel circuit includes a first amplifying section, a second amplifying section, a third resistor connected between a non-inverting input terminal of the first amplifying section and a non-inverting input terminal of the second amplifying section, and a current source. In the offset cancel circuit, the current source causes a constant current to flow through the third resistor to cancel an offset voltage from output signals of first and second amplifying sections, the constant current corresponding to the offset voltage contained in first and second output signals output from a bridge resistance type sensor.

Abstract: Methods and systems for calibrating a sensor for measuring an analyte in a patient monitoring system are disclosed. The method includes calculating sensor drift; calibrating the sensor using at least one calibration fluid; and periodically updating the sensor calibration based on the sensor drift calculation. The system adjusts a gas concentration in a fluid. The method in one of several variations includes providing a calibration fluid; setting the analyte concentration in the first fluid to a first concentration with an adjustment mechanism; measuring the first analyte concentration with the sensor; setting the analyte concentration in the first fluid to a second concentration; measuring the second analyte concentration with the sensor; and determining the calibration coefficients for the sensor from the measured first and second analyte concentrations.

Abstract: A pressure detector detecting a pressure of cold or hot water; a temperature detector detecting a temperature of a pressure sensor; correcting equation storage storing, cold water correcting equation information applied when the temperature detected by the temperature detector is included in a cold water temperature range, and hot water correcting equation information applied when the temperature detected by the temperature detector is included in a hot water temperature range; a temperature range determiner determining the temperature range that includes the temperature detected by the temperature detector as either a cold water temperature range or a hot water temperature range; and a correction calculating portion using the correcting equation corresponding to the temperature range determined by the temperature range determiner correcting the detection signal by the pressure detector, and outputting the post-correction signal as a measurement signal.

Abstract: An arrangement and method for providing compensation to a cyclical input signal is disclosed. The arrangement comprises a first detection unit (20) for detecting a first event in a cyclical output signal; a compensation signal generation unit (14) for generating a compensation signal; and a signal combination unit (8) for combining the compensation signal and the cyclical input signal to obtain the cyclical output signal. The compensation signal generation unit (14) is arranged to adjust the compensation signal at an instant which has a determined relationship with the detection of the first event. By adjusting the compensation signal at the right instant in a cycle of the cyclical output signal, the adjustment will not influence the further processing of the cyclical output signal. The method can be used to compensate the offset and sensitivity characteristics of a sensor.

Abstract: An integrated circuit includes a transducer and transducer circuitry and additional elements useful in testing the transducer and transducer circuitry. A first power supply terminal and a second power supply terminal are for being directly connected to an external power supply terminal. A power bus is connected to the first power supply terminal. A logic function is for determining if the second power supply terminal is receiving power and if an automatic calibration test of the transducer and transducer circuitry has been run. An automatic calibration is for running an automatic calibration test on the transducer and transducer circuitry if the logic means determines that the second power supply terminal is receiving power and the automatic calibration test of the transducer and transducer circuitry has not been run.

Abstract: A bias value associated with a sensor, e.g., a time-varying, non-zero value which is output from a sensor when it is motionless, is estimated using at least two, different bias estimating techniques. A resultant combined or selected bias estimate may then be used to compensate the biased output of the sensor in, e.g., a 3D pointing device.

Abstract: Zero and calibration drift errors in a magnetic flow meter can be detected and automatically corrected. A zero error can be detected by measuring an amplifier output when the meter's electromagnet is inactive. Automatic calibration of the span can be done by adding a signal to a measured electrode voltage at an amplifier input, subtracting the expected amplified value of that signal at the output and adjusting the amplifier gain responsive to the difference in signal magnitude.

Abstract: Systems and methods of determining parameter values in a downhole environment are described. An example method of determining a parameter value using calibration information is described. The calibration information corresponding to different parameter ranges in a downhole environment. The method includes determining a parameter range in the downhole environment using a controller and obtaining first calibration information or second calibration information based on the parameter range. The first calibration information associated with a first parameter range and the second calibration information associated with a second parameter range. The method also includes receiving an output signal from a sensor associated with the parameter and using the obtained calibration information to determine the parameter value based on the output signal received.

Abstract: An assembly tool is provided. The assembly tool comprises a body and a gripper mount slidably mounted to the body with a first actuator. The first actuator is configured to slide the gripper mount from a first position to a second position along an axis. The assembly tool also comprises a gripper assembly slidably mounted to the gripper mount with a second actuator. The second actuator is configured to facilitate displacement of the gripper assembly with respect to the gripper mount along the axis. The assembly tool also comprises an encoder configured to indicate a displacement distance between an expected position and an actual position of the gripper assembly with respect to the gripper mount along the axis when the gripper mount is in the second position.

Abstract: An apparatus for improving the procedure for quantifying the volume of liquid dispensed by a liquid-dispensing mechanism of an analytical instrument. The apparatus of this invention comprises (a) at least one weigh cup; (b) at least one standard mass; (c) at least one transducer assembly to convert a value of weight to an electrical response; and (d) at least one electronic circuit for converting the electrical response to a measurement of volume. This invention provides a method for calibrating readings of the volume of liquid dispensed by a liquid-dispensing mechanism of an analytical instruments so that absolute measurements of the volume of liquid dispensed can be obtained.

Abstract: Device for determining an error induced by a high-pass filter in a signal, including a unit (3) for calculating the error according to the formula: E(t)=Ve(t)?Vs(t)=2·?·Fc·??=t0t(Vs(?)? Vs(?))·d?+E(t0) with: E(t) the value of the error induced by the high-pass filter, as a function of the time variable t, ?the trigonometric constant, Fc the cutoff frequency of the high-pass filter, t0 the initial instant, ?integration variable, Ve the signal input to the high-pass filter, Vs the signal output by the high-pass filter, Vs the mean value of the signal Vs. A method of correcting the error induced is also presented and applicable to the error correction of a piezoelectric pressure sensor.

Abstract: A bias value associated with a sensor, e.g., a time-varying, non-zero value which is output from a sensor when it is motionless, is estimated using at least two, different bias estimating techniques. A resultant combined or selected bias estimate may then be used to compensate the biased output of the sensor in, e.g., a 3D pointing device.

Abstract: The present invention relates to a method of detecting non-linear operation of a measuring device comprising an array of transducers and at least one receiver channel portion. The method comprises receiving measured signals through transducers of the array, processing the measured signals from the transducers through the receiver channel portion, combining the processed measured signals to produce a combined measurement signal, and detecting non-linearity of the combined measurement signal and non-linear operation of the measuring device by detecting saturation of the receiver channel portion. In one embodiment, the receiver channel portion comprises an analog-to-digital converter, a threshold is assigned to a digital output of the analog-to-digital converter, and saturation of the receiver channel portion is detected when the digital output of the analog-to-digital converter oversteps the assigned threshold. In one application of the invention, the measuring device is a non-destructive testing device.

Abstract: An indicating instrument for a vehicle includes a step motor including a field winding, a pointer, a stopper device for stopping the pointer, which is rotating in a zero-reset direction, at a stopper position, a detecting device for detecting induced voltage of the field winding at each of detecting points, a control device for performing zero-reset control, whereby a drive signal is controlled to rotate the pointer in the zero-reset direction. In a state of abnormal detection in which the induced voltage larger than a predetermined set value is detected at a zero point; and the induced voltage equal to or smaller than the set value is detected at a next detecting point to the zero point, the control device assumes synchronization loss of the step motor and continues the zero-reset control until an assumptive electrical angle corresponding to a rotational position of the pointer reaches the zero point.

Abstract: An indicating instrument includes a step motor having a field winding, a pointer, a reduction gear mechanism having gears, a stopper device for stopping the pointer at a stopper position, a detecting device for detecting induced voltage of the winding at each of detecting points that include a zero point corresponding to the stopper position, a control device for controlling a drive signal, and an updating device for updating the zero point based on the induced voltage during zero-reset control performed by the control device. The control device performs return control, whereby the pointer rotates to a return point in an indication value increasing direction and then returns to a waiting point in a zero-reset direction to stand by at the waiting point, prior to zero-reset control, whereby the pointer rotates from the waiting point in the zero-reset direction.

Abstract: The present invention relates to a method of detecting non-linear operation of a measuring device comprising an array of transducers and at least one receiver channel portion. The method comprises receiving measured signals through transducers of the array, processing the measured signals from the transducers through the receiver channel portion, combining the processed measured signals to produce a combined measurement signal, and detecting non-linearity of the combined measurement signal and non-linear operation of the measuring device by detecting saturation of the receiver channel portion. In one embodiment, the receiver channel portion comprises an analog-to-digital converter, a threshold is assigned to a digital output of the analog-to-digital converter, and saturation of the receiver channel portion is detected when the digital output of the analog-to-digital converter oversteps the assigned threshold. In one application of the invention, the measuring device is a non-destructive testing device.

Abstract: A system for preventing overflow of a toilet includes a sensor, a processor and an actuator. The sensor senses a parameter caused by fluid dynamics within the toilet during a flush cycle. The parameter may involve vibration, sound, pressure, fluid flow rate or other detectible characteristics of the toilet. The processor uses information regarding the parameter that is gathered by the sensor to evaluate the condition of the flush cycle to determine if an impeded flush condition exists. In the event of an impeded flush condition, the processor directs the actuator to close a valve, which may be the toilet flapper valve in some embodiments. Also disclosed are methods for preventing toilet overflow, detecting an impeded flush condition and calibrating the system.

Abstract: An arrangement and method for providing compensation to a cyclical input signal is disclosed. The arrangement comprises a first detection unit (20) for detecting a first event in a cyclical output signal; a compensation signal generation unit (14) for generating a compensation signal; and a signal combination unit (8) for combining the compensation signal and the cyclical input signal to obtain the cyclical output signal. The compensation signal generation unit (14) is arranged to adjust the compensation signal at an instant which has a determined relationship with the detection of the first event. By adjusting the compensation signal at the right instant in a cycle of the cyclical output signal, the adjustment will not influence the further processing of the cyclical output signal. The method can be used to compensate the offset and sensitivity characteristics of a sensor.

Abstract: A method of calibrating an individual sensor of a particular sensor type whose output varies non-linearly with at least one measured quantity and at least one operating condition. The first step includes producing a set of calibration curves for each sample sensor of the particular sensor type. The resulting sets of calibration curves are then averaged and the results used to produce a generic calibration surface for the particular sensor type showing its variation. Individual calibration measurements are then taken for a number of different values of the measured quantity at a small number of discrete values. The individual calibration readings are then used to map the generic calibration surface to the individual calibration measurements of the individual sensor.

Abstract: A method of calibrating a metabolic analyzer incorporating an oxygen analyzer and a NDIR carbon dioxide analyzer in the field that does not require the use of gas cylinders containing gases of known concentration is described. In calibrating the CO2 detector, at the time of factory setup, the detector output for a gas of a known concentration is measured and stored in the memory of the metabolic analyzer's microprocessor, as is the detector output voltage when the IR source is dimmed by a known percentage. Subsequently, in the field, CO2 levels in ambient air and cell pressure are measured at two different flow rates through the sample chamber and the IR source is again dimmed by the same percentage as had been used at the time of factory setup. Based upon the resulting readings, both the zeroing and span adjustment factors can be computed.

Abstract: For calibrating a humidity sensor, the latter is used to measure the relative humidity (U1, U2) at each of two known gas pressure values (P1, P2), likewise to be measured if necessary. At the same time, other ambient conditions are kept constant. A correction value for correction of the measured values of the humidity sensor to be subtracted from the latter is then obtained from the formula: k=((P1/P2)*U2?U1)/(P1/P2?1). The humidity sensor is thus capable of calibration without measurement of the actual humidity value.

Abstract: A method of increasing consistency between separate parametric measurement readings that are taken with an electron beam imaging tool at different times within a period of time, by correcting drift in the imaging tool at a time frequency that is less than a time period during which the drift is anticipated to be undesirably large.

Abstract: A method for verifying the adjustment of a plurality of measurement instruments includes measuring a first value of an un-verified test value of a parameter with a first measurement instrument; measuring a second value of the same un-verified test value of a parameter with a second measurement instrument; comparing the first value with the second value; and determining an adjustment verification state based on the comparison.

Abstract: A circuit and method for determining the wiper resistance of a potentiometer that includes the step of electrically coupling a sense resistor having a substantially constant sense resistance to the potentiometer third terminal. The potentiometer is electrically energized, and a potentiometer voltage, which is a voltage potential between the potentiometer first and second terminals, is determined. The wiper position is determined based at least in part on the determined potentiometer voltage. The sense resistor is electrically coupled to a potential that causes a wiper current to flow through the wiper and sense resistor. A magnitude of the wiper current is determined, and the wiper resistance is determined based at least in part on the potentiometer resistance, the determined potentiometer position, the determined wiper current magnitude, and the sense resistance.

Abstract: An apparatus including: an optical sensor comprising an optical transmitter and an optical receiver; and a calibration system configured to change calibration of the sensor when a measurement taken at the optical receiver, while the optical transmitter is on and the apparatus is in use, passes a test.

Abstract: A programmable liquid sampler for obtaining and digitally analyzing multiple, sequential samples in real time from an external source of liquid to be analyzed comprises an adaptive feedback algorithm for correcting sample weight measurements occasioned by vacuum delays. A sampling assembly receives and at least temporarily stores a sample drawn by suction through an air port that can also pressurize the chamber. A load cell determines sample mass through a logic controller that implements adaptive feedback by recognizing a desired target sample size, requesting an initial sample, and measuring the initial sample size. A variable scaling factor is derived by comparing the target sample size to said measured sample size and the subsequent requesting size is scaled. Samples can be stored in multiple compartments of a radial table that is indexed by the computer software for proper sample control.

Abstract: A self-diagnostic measurement method to detect microbridge null drift and performance. An ASIC can be designed to include a self-diagnostic feature that automatically occurs at start up or upon command in Normal Operation whereby the temperature compensated microbridge null can be measured in a state of very low thermal energy and allows for the tracking of microbridge null stability versus time. An Airflow Combi-Sensor ASIC (Heimdal) with its strategic partner ZMD can be developed and can be implemented in the form of a self-diagnostic feature that occurs when power is first applied to the ASIC or upon command. When the self-diagnostic is initiated, power is removed and after the electronics have settled, a small power can be applied to the microbridge to measure the bridge null with reduced sensitivity to flow due to self-heating.

Abstract: A sensor incorporates a dual range ASIC (Application Specific Integrated Circuit) for accurately sensing and measuring sensor input over extensive range along with an improved resolution. The sensor can incorporate an ASIC utilizing signals from a MEMS-based piezoresistive Wheatstone bridge. Signals can also come from capacitive pressure measurement sources. The signals can be converted to digital bit counts where calibration coefficients can be implemented to achieve high precision. The calibration coefficients corresponding to bit counts can be compared with transition points that are recorded into ASIC for effectively distinguishing different sensor ranges. The transition points can be stored in an EEPROM fabricated to suit ASIC applications.

Abstract: An electromagnetic flowmeter for giving a magnetic field to a measurement fluid, detecting an electric signal occurring in the measurement fluid according to the magnetic field, and computing a flow quantity value based on the electric signal includes a zero point measurement section for measuring a zero point of the measurement fluid; a storage section for storing the measured zero point measurement value; a determination section for determining whether or not the difference between the preceding zero point measurement value stored in the storage section and the present zero point measurement value is beyond a predetermined value range; and at least either a transmission section for transmitting the determination result or a display section for displaying the determination result when the determination section determines that the difference is beyond the predetermined value range.

Abstract: In a travel angle detection system for a mobile object having a detector installed in the mobile object to produce angular velocity outputs successively, the detector outputs are read and one output is determined as a provisional calibration value indicative of zero-point. Integrated values of differences between the calibration value and successive outputs and output variation width are calculated. When they are within predetermined permissible ranges, the mobile object is determined to be in static condition and the calibration value is corrected by an average value of the integrated values. The travel angle of the mobile object is detected from the calibrated outputs of the detector, thereby achieving accurate calibration of detector output by enabling accurate determination of the static condition.

Abstract: A method of calibrating an individual sensor whose output varies with at least one operating condition. A generic calibration curve is produced for the variation of the sensor reading with the at least one operating condition for the particular sensor type of the individual sensor. Calibration readings are then taken for the individual sensor at just a small number of discrete values for the at least one operating condition which fall within the full range of operating values for the at least one operating condition for which the sensor is to be calibrated. Using the calibration readings, the generic calibration curve is then scaled in order to fit the generic curve to the individual sensor.

Abstract: A method and system for calibrating an analog sensor used in a digital measurement system is provided. The design comprises generating a precise pressure value set at multiple calibration points and supplying said precise pressure value set to an uncalibrated pressure sensor, detecting sensor changes for the uncalibrated pressure sensor based on each precise pressure value generated, polling an actual pressure reading associated with a sensor change for the uncalibrated pressure sensor for each calibration point, and establishing a mathematical relationship between measured value readings and actual pressure for the uncalibrated sensor. Establishing the mathematical relationship converts the uncalibrated sensor to a newly calibrated sensor. A known good sensor may be employed to enhance calibration reliability.

Abstract: A thermally controlled stage is connected within one arm of a bridge of a capillary bridge viscometer so that the bridge can be balanced in situ to provide accurate measurement signals. The thermally controlled stage includes a tuning capillary tubing portion that is wrapped around a thermally conductive core. A resistance heater or a Peltier thermoelectric device is located in close proximity to the capillary tubing portion. The heater or Peltier device and the capillary tubing portion are located within a thermally insulated housing. The heater or Peltier device varies the temperature of the capillary tubing portion to cause a corresponding change in the flow impedance of the tuning capillary tubing portion of the arm of the bridge in which the thermally controlled stage is connected. The temperature of the tuning capillary tubing portion is monitored and adjusted until any pressure differential across the bridge is eliminated, whereby to trim in the balance of the bridge.

Abstract: A method of compensating sensor data and a method of evaluating an interlock of an interlock system, in which an allowable variation between sensors varying depending on a driving time for a set of equipment, an RF time, the number of wafers, etc. is minimized, thereby enhancing detection reliability of a defective wafer.

Abstract: A self-calibrating carbon dioxide sensor that includes a carbon dioxide detector and a carbon dioxide gas generator. In some embodiments, the carbon dioxide gas generator includes a heating element and a carbon dioxide gas releasing solid material in thermal communication with the heating element. The carbon dioxide gas releasing solid material releases carbon dioxide when heated by the heating element. Methods of calibrating a self-calibrating carbon dioxide sensor are also disclosed.

Abstract: An acoustic flowmeter calibration method and sampling system address a variation in acoustic transducer delay time with increasing temperature. In one aspect, calibration of the path length between the sending and receiving transducers and calibration of the transducer delay time over a wide temperature range are optimized. In another aspect, the flowmeter output is temperature compensated based on the exhaust flowmeter gas temperature. These two aspects may be embodied in an ultrasonic flowmeter for exhaust gas measurement individually or in combination in accordance with the invention.

Abstract: A device which includes an acceleration sensor for outputting small differential voltages VIP and VIN using resistance changes, and an output amplifier for amplifying the voltage difference. The output amplifier includes an offset-voltage adjustment circuit and an instrumentation amplifier. The instrumentation amplifier includes a first Op-amp having inputs connected to VIP and offset-voltage input terminals, a second Op-amp having inputs connected to VIN and VCOM input terminals, and a third Op-amp having inputs connected to outputs of the first and second Op-amps via resistors. The reference voltage VCOM of the instrumentation amplifier output is also applied to the second Op-amp.

Abstract: An apparatus for improving the procedure for quantifying the volume of liquid dispensed by a liquid-dispensing mechanism of an analytical instrument. The apparatus of this invention comprises (a) at least one weigh cup; (b) at least one standard mass; (c) at least one transducer assembly to convert a value of weight to an electrical response; and (d) at least one electronic circuit for converting the electrical response to a measurement of volume. This invention provides a method for calibrating readings of the volume of liquid dispensed by a liquid-dispensing mechanism of an analytical instruments so that absolute measurements of the volume of liquid dispensed can be obtained.

Abstract: A physical quantity sensor detecting physical quantity, such as acceleration or angular velocity, is provided and mounted on, for example, a vehicle. The sensor has a physical quantity transducer and the first to third circuits. The transducer senses physical quantity acting in a direction determined with respect to a predetermined detection axis of the transducer to output a detection signal corresponding in level to the physical quantity. The first circuit receives the detection signal and output a first physical quantity signal depending in level on the detection signal. The second circuit produces a second physical quantity signal from the first physical quantity signal, the second physical quantity signal being larger in magnitude the first physical quantity signal. The third circuit receives the first and second physical quantity signals and outputs a signal consisting of the first and second physical quantity signals alternately selected and lined up sequentially in time.

Abstract: A measurement device with a cylindrical housing (2), with a sensor element and with an adjustment element (6) made, for example, as a potentiometer, for setting at least one parameter of the measurement device. The measurement device (1) is especially easily and still accurately and reproducibly settable by there being at least one rotary adjustment ring, the adjustment ring being made as a housing sleeve (7) for setting the parameter.

Abstract: A standard medical or surgical tool's axis is located by attaching to the tool a plurality of a location indicating elements or markers having a known geometric or spatial relationship, and placing the tool in a tool calibrator that supports the tool in a manner that allows tools of different diameters to be rotated while maintaining the tool's axis in a fixed or stable orientation. As the tool is rotated, a marker locating system tracks the positions of the markers on the tool and then extrapolates or determines the axis of rotation with respect to the markers clamped to the tool. The tool calibrator has a second set of position indicating elements or markers with fixed geometric or spatial relationship with one another and with respect to a stop, against which the end or tip of the tool is placed.

Abstract: An output port open control device (65) allows a port (P3) which outputs PWM signals of a Cos+ side to be in a high impedance state in a period in which respective PWM signals of Cos+ and Cos? supplied to a S-phase coil (22) of a stepping motor (2) are in a ground level, induced voltage corresponding to a magnetic flux variation caused in accordance with rotation of a magnet rotor (23) is generated in the S-phase coil (22), a voltage comparator (72) compares the induced voltage with a previously set threshold value and outputs presence or absence of the induced voltage, and a zero-reset judging device (66) determines that a pointer (4) is in the middle of rotation when the induced voltage is detected, and determines that the pointer (4) is in contact with a stopper mechanism (5) when it is not detected.

Abstract: A method of correcting a pointing position of a pointer rotated by a stepper motor includes the steps of: performing a prereset operation in which the pointer is rotated to a reset operation starting position that represents a pointing position of the pointer which is shifted by a predetermined amount in a plus direction of a scale from a reset position where a pin which is rotated in conjunction with a rotation of the pointer abuts against a fixed stopper; after the prereset operation, performing a reset operation in which the pointer is rotated in a minus direction of the scale to the reset position; and after the reset operation, performing a correcting operation in which the pointer is rotated in the plus direction up to a reference pointing position which is indicated by previously stored reference pointing positional information.