JP2005121437A - Calibration device for angle sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance the reliability of a calibration work for an angle sensor, in a calibration device for the angle sensor. <P>SOLUTION: This device comprises the angle sensors 21b, 21a for detecting turning angles of a boom 4b and an arm 4a, a storage device 12 for storing a design output characteristic indicating a relation between output values xb, xa of the angle sensors and detection angles yb, ya corresponding to the output values, cylinders 7b, 7a for turning the boom 4b and the arm 4a to the first posture and second posture. The design output characteristics are corrected in response to deviations ΔIb, ΔIa between design values Ib, Ia settled on the basis of the design output characteristic in the first posture and the sensor output values xb, xa corresponding to the design values, and in response to deviations ΔHb, ΔHa between a boom height Hb and an arm height Ha determined on the basis of the design output characteristic in the second posture and observed values Hbm, Ham of the heights. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an angle sensor calibration device that detects the angle of a rotating member such as a boom or an arm.

  Conventionally, a working machine having a boom and an arm is provided with an angle sensor such as a potentiometer, and a boom angle and an arm angle are obtained based on an output signal of the angle sensor and output characteristics of a predetermined angle sensor. In this case, the output of the sensor includes errors due to variations in the sensor mounting position and the sensor itself. Therefore, if the design output characteristics of the sensor described in the catalog etc. are used as they are, the boom angle etc. cannot be obtained accurately, and in order to improve the accuracy of the angle detection value, calibration of the angle sensor is generally required. Become.

  As a calibration device for this type of angle sensor, an angle sensor output at both stroke ends of a work implement is actually measured, and a boom angle or the like is obtained based on output characteristics obtained by connecting these two points with a straight line. (See, for example, Patent Document 1).

Japanese Patent Publication No.7-116723

  However, in the apparatus described in Patent Document 1, the sensor output characteristics are obtained only by the actual sensor output values at both stroke ends without considering the design output characteristics of the angle sensor. It is not possible to recognize how far it is from. For example, when the sensor is defective, the difference between the sensor output and the design value becomes large. If the output characteristics of the sensor are obtained only from the actual measured sensor output, the reliability of the angle detection value is sufficiently secured. Can not.

The calibration of the angle sensor according to the present invention is provided in a rotatable rotating member, an angle sensor for detecting the rotating angle of the rotating member, an output signal of the angle sensor, and a detection angle corresponding to the output signal, Storage means for storing a design output characteristic indicating the relationship between the first and second rotation means, a rotation means for rotating the rotation member to the first attitude and the second attitude, and a first position determined based on the design output characteristic in the first attitude. And a second reference value determined based on the design output characteristics in the second posture and a second actual value corresponding to the reference value, and the second actual value corresponding to the reference value. And a correction means for correcting the design output characteristic according to the deviation.
The design output characteristic is offset in accordance with the deviation between the first reference value and the first actual measurement value in the first posture, and in accordance with the deviation between the second reference value and the second actual measurement value in the second posture. The correcting means may be configured to change the gain of the output characteristic after the offset.
It is preferable that the maximum rotation position of the rotation member be in the first position and the arbitrary rotation position of the rotation member be in the second position.
An alarm means for generating an alarm when the deviation exceeds a predetermined value can be provided, and an instruction means for instructing a calibration work procedure can be provided.

  According to the present invention, the first reference value in the first posture and the second reference value in the second posture determined based on the design output characteristics of the angle sensor, and the first reference value corresponding to each of these reference values. The design output characteristic is corrected according to the deviation between the actual measurement value and the second actual measurement value. As a result, the angle sensor can be calibrated in consideration of the design output characteristics, and the reliability of the detection value of the sensor is increased.

Hereinafter, an embodiment of a calibration apparatus for an angle sensor according to the present invention will be described with reference to FIGS.
FIG. 1 is an external side view of a hydraulic excavator 1 having an angle sensor calibration device according to an embodiment of the present invention. The excavator 1 includes a traveling body 2, a revolving body 3 provided on the traveling body 2 so as to be turnable, and a front attachment 4 provided on the revolving body 3 so as to be turnable. The front attachment 4 is supported by the boom cylinder 7b so as to be rotatable on the revolving body 3 with the pivot shaft 5b as a fulcrum, and supported by the arm cylinder 7a with the pivot shaft 5a at the tip of the boom as a fulcrum. And a bucket 4c that is rotatably supported via a bucket cylinder 7c with a pivot shaft 5c at the tip of the arm as a fulcrum. In the figure, H5b is the height of the boom base end with respect to the reference planes (ground) G0, G1 where the lower traveling body 2 is located, Hb is the height of the boom tip position 6b, and Ha is the height of the arm tip position 6a. Respectively.

  An angle sensor 21b that detects the rotation angle of the boom 4b relative to the revolving structure 3 is mounted on the rotation shaft 5b, and an angle sensor 21a that detects the rotation angle of the arm 4a relative to the boom 4b is mounted on the rotation shaft 5a. It is installed. The angle sensors 21b and 21a are composed of potentiometers, and output electric signals proportional to the rotation amounts of the boom 4b and the arm 4a.

  FIG. 2 is a block diagram of the calibration apparatus according to the present embodiment. Angle sensors 21 b and 21 a and a terminal device 20 are connected to the controller 10. The controller 10 stores a program used for a predetermined calculation in the controller 10 and various constants used for the calculation (such as body part dimensions, design values and correction values of output characteristics of the sensors 21b and 21a), and the like. And a CPU 11 that executes a predetermined calculation according to a program stored in the storage device. A signal from the terminal device 20 is input to and output from the storage device 12. The terminal device 20 includes a signal input unit such as a keyboard and a display unit such as a monitor, and is detachable from the controller 10. The calibration work start switch 22 is a switch for instructing the start of the calibration work.

  The output signals xb and xa of the angle sensors 21b and 21a are input to the boom angle conversion unit 31b and the arm angle conversion unit 31a of the CPU 11, respectively. The boom angle conversion unit 31b converts the output value xb into the boom angle yb based on the output characteristics of the angle sensor 21b stored in the storage device 12. The arm angle conversion unit 31 a converts the output value xa into the arm angle ya based on the output characteristics of the angle sensor 21 a stored in the storage device 12.

  In the attitude calculation unit 32, processing described later is performed based on signals from the boom angle conversion unit 31b, the arm angle conversion unit 31a, the storage device 12, the terminal device 20, and the calibration work start switch 22, and the angle sensors 21b and 21a have unique processing. While calculating | requiring an output characteristic, the attitude | position of the front attachment 4 is calculated using the output characteristic. The sensor-specific output characteristics obtained by the posture calculation unit 32 are stored in the storage device 12. The signal from the attitude calculation unit 32 is also output to the display unit of the terminal device 20 and the monitor of the operation panel.

  The vehicle body control unit 33 performs various calculations for controlling the vehicle body based on the attitude of the front attachment 4 calculated by the attitude calculation unit 32. For example, when front trajectory control is performed, a control signal is calculated so that the front posture calculated by the posture calculation unit 32 is the target posture. In addition, when overload prevention control is performed, a control signal that suppresses the work radius calculated by the posture calculation unit 32 within the limit work radius is calculated. The control signal calculated by the vehicle body control unit 33 is output to various actuators such as the boom cylinder 7b and the arm cylinder 7a, but is not shown in the figure.

Next, an outline of the calibration method of the angle sensors 21b and 21a according to the present embodiment will be described. A characteristic 91 in FIG. 3 is a design value (design output characteristic) of the output characteristic indicating the relationship between the output value x of the sensors 21b and 21a described in the catalog and the rotation angle detection value y. This characteristic 91 is a linear expression that is uniquely determined by an offset (intercept) and a gain (tilt), and the rotation angle y can be calculated by the following expression (I).
y = A × (x−I) + J (I)
However, A is the gain of the output characteristic, and I and J are the rotation angle J when the output value x = I, which corresponds to the offset of the output characteristic. These A, I, and J are design values (constants) and are stored in the storage device 12 in advance.

Here, the gain A is mainly affected by the accuracy in manufacturing the sensor, and the offsets I and J are affected by an error in mounting the sensor. Accordingly, the output characteristic unique to the sensor is deviated from the design value characteristic 91 as shown in the characteristic 93, for example. In order to obtain the rotation angle y from the output value x with high accuracy, It is necessary to correct. Assuming that the gain correction value is ΔA and the offset correction value at the rotation angle J is ΔI, the corrected arithmetic expression is the following expression (II).
y = (A−ΔA) × (x− (I−ΔI)) + J (II)

  In order to obtain the correction value, in this embodiment, first, the front attachment 4 is set to the first posture (y = J) by the operator's operation, and the output value x1 of the sensors 21b and 21a is designed in this state. The deviation of the value I (correction value ΔI) is calculated (characteristic 91 → characteristic 92). Next, the front attachment 4 is set in the second posture, the boom height and the arm height in the second posture are measured, and the output values x2 and output characteristics of the sensors 21b and 21a in the second posture are measured. Use to calculate the boom angle and arm angle. Then, the gain is automatically adjusted in a state where ΔI is fixed so that the deviation between the actually measured value and the calculated value of the angle is small, and the correction value ΔA is calculated (characteristic 92 → characteristic 93).

  In the present embodiment, for example, as shown in FIG. 7, the state in which the boom cylinder 7b and the arm cylinder 7a are respectively extended to the maximum is the first posture, and the boom cylinder 7b and the arm cylinder 7a are moved as shown in FIG. The state that is arbitrarily degenerated is defined as the second posture. The storage device 12 stores design values (I and J in FIG. 3) of sensor output in the first posture. The first posture is a reference posture in which the cylinders 7b and 7a are expanded and contracted to the stroke end, and the actually measured values of the boom angle and the arm angle in this reference posture are substantially equal to the design values.

  The calculation described above is executed by the attitude calculation unit 32. 4 to 6 are flowcharts showing an example of processing related to the calibration of the sensors 21b and 21a executed by the attitude calculation unit 32. FIG. First, in step S1 of FIG. 4, it is determined whether or not the calibration work start switch 22 is turned on. If step S1 is affirmed, the process proceeds to step S2, and if denied, the process is terminated. In step S <b> 2, it is determined whether or not the terminal device 20 is connected to the controller 10. If step S2 is negative, the process proceeds to step S3, a message to connect the terminal device 20 is output to the monitor, and the process returns to step S2.

  When step S2 is affirmed, the process proceeds to step S4, and a message to set the front attachment 4 to the first posture is output to the monitor. Next, in step S5, it is determined whether or not the first posture set is completed. This determination is made based on whether or not the worker has performed a predetermined key operation of the terminal device 20 after the completion of the first posture setting. The first posture may be detected by a limit switch or the like, and the completion of the first posture set may be automatically determined. Step S5 is repeated until affirmative. If step S5 is affirmed, the process proceeds to step S6, and the deviations ΔIb, ΔIa between the output values xb, xa (actually measured values) of the angle sensors 21b, 21a and the design values Ib, Ia stored in the storage device 12 are calculated.

  Next, in step S7, it is determined whether or not the absolute values of the deviations ΔIb and ΔIa are smaller than predetermined limit values LΔIb and LΔIa. If step S7 is negative, the process proceeds to step S8. In this case, since the deviation between the output values xb, xa and the design values Ib, Ia is large, there is a high possibility that the sensors 21b, 21a are defective, and there is a problem in the reliability of the sensor output. Therefore, since it is not preferable to continue the work as it is, a warning message is output to the monitor in step S8, and the work is terminated. If step S7 is affirmed, the process proceeds to step S9, the deviations ΔIb and ΔIa of step S6 are stored in the storage device 12, and the process proceeds to step 11 in FIG.

  In step S11, a message to set the front attachment 4 to the second posture is output to the monitor. Next, in step S12, it is determined whether or not the second posture set is completed. This determination is made based on whether or not the worker has performed a predetermined key operation on the terminal device 20 after the completion of the second posture setting. Step S12 is repeated until affirmative. When step S12 is affirmed, the process proceeds to step S13, and a message is output to the monitor to measure the height of the boom tip. The boom tip height can be measured using, for example, a measure or the like, but may be measured by other methods. Next, in step S14, it is determined whether or not the actual measured value Hbm of the boom tip height is input by a key operation of the terminal device 20. Step S14 is repeated until affirmative.

  If step S14 is affirmed, the process proceeds to step S15, and ΔIb stored in step S9 is substituted for ΔI in the above equation (II), and the output value xb of the angle sensor 21b is substituted for x in the above equation (II). yb is calculated. In this case, an initial value (for example, ΔAb = 0) is substituted for ΔA. Then, the boom height Hb is calculated from the calculated boom angle yb, the boom length stored in advance, and the boom base end height H5b. In the next step S16, a deviation ΔHb between the boom height detection value Hb and the actual measurement value Hbm is obtained.

  Next, in step S17, it is determined whether or not the boom height deviation ΔHb (absolute value) is smaller than a predetermined limit value LΔHb. Here, the limit value LΔHb is a limit value of the gain adjustment amount. When the deviation ΔHb is greater than or equal to the limit value LΔHb due to a failure of the sensor 21b or the like, the gain adjustment amount increases remarkably and there is a problem with the reliability of the sensor 21b. Therefore, in this case, it is not preferable to continue the work as it is, so that a warning message is output to the monitor in step S18 and the work is terminated.

  On the other hand, if it is determined that the deviation ΔHb (absolute value) is smaller than the limit value LΔHb, the process proceeds to step S19, and it is determined whether the deviation ΔHb (absolute value) is smaller than a predetermined allowable value Eb. If step S19 is negative, the process proceeds to step S20, and the correction value ΔAb of the boom angle sensor 21b is increased or decreased by a predetermined value. In this case, when ΔHb is positive (when the detection value Hb is larger than the actual measurement value Hbm), the correction value ΔAb is increased by a predetermined value, and when ΔHb is negative (when the detection value Hb is smaller than the actual measurement value Hbm), correction is performed. The value ΔAb is decreased by a predetermined value.

  Next, in step S21, the boom angle yb is calculated by substituting the correction value ΔAb in step S20 for ΔA in the above equation (II), and the boom height Hb is calculated using the boom angle yb. In step S22, a deviation ΔHb between the boom height detection value Hb and the actual measurement value Hbm is obtained, and the process returns to step S19. Steps S19 to S22 are repeated until step S19 is positive. If step S19 is affirmed, the process proceeds to step S23, the correction value ΔAb is stored in the storage device 12, and the process proceeds to step S31 in FIG.

  In step S31, a message that the height of the arm tip is actually measured in the second posture is output to the monitor. The arm tip height can be measured using, for example, a measure or the like, but may be measured by other methods. Next, in step S <b> 32, it is determined whether or not an actual arm Ham height value Ham is input by a key operation of the terminal device 20. Step S32 is repeated until affirmative.

  If step S32 is affirmed, the process proceeds to step S33, and ΔIa stored in step S9 is substituted for ΔI of the above equation (II), and the output value xa of the angle sensor 21a is substituted for x of the above equation (II). ya is calculated. In this case, an initial value (for example, ΔAa = 0) is substituted for ΔA. Then, using the boom height detection value Hbm that satisfies the condition that the deviation ΔHb (absolute value) is smaller than the allowable value Eb, the calculated arm angle ya, and the arm length stored in advance, an arm as a detection value is obtained. The height Ha is calculated.

  Next, in step S34, a deviation ΔHa between the arm height detection value Ha and the actual measurement value Ham is obtained. In step S35, it is determined whether or not the deviation ΔHa (absolute value) is smaller than a predetermined limit value LΔHa. Here, the limit value LΔHa is a limit value of the gain adjustment amount. When the deviation ΔHa is greater than or equal to the limit value LΔHa due to a sensor failure or the like, the gain adjustment amount increases remarkably, and there is a problem in the reliability of the sensor 21a. Therefore, in this case, it is not preferable to continue the work as it is, so that a warning message is output to the monitor in step S36 and the work is terminated.

  On the other hand, if it is determined that the deviation ΔHa (absolute value) is smaller than the limit value LΔHa, the process proceeds to step S37, where it is determined whether the deviation ΔHa (absolute value) is smaller than a predetermined allowable value Ea. If step S37 is negative, the process proceeds to step S38, and similarly to step S20, the correction value ΔAa of the arm angle sensor 21a is increased or decreased by a predetermined value according to the sign of ΔHa. Next, in step S39, the arm angle ya is calculated by substituting the correction value ΔAb in step S38 for ΔA in the above equation (II), and the arm height Ha is calculated using this arm angle ya. In step S40, a deviation ΔHa between the arm height detection value Ha and the actual measurement value Ham is obtained, and the process returns to step S37. Steps S37 to S40 are repeated until step S37 is positive. When step S37 is affirmed, the process proceeds to step S41, the correction value ΔAa is stored in the storage device 12, and the process ends. Through the above processing, the output characteristics unique to the sensor are stored in the storage device 12.

Next, a calibration method for the angle sensors 21a and 21b using the calibration apparatus according to the present embodiment will be described.
In performing calibration work of the sensors 21a and 21b, first, a terminal device is connected to the controller 20, and the calibration work start switch 22 is turned on. As a result, the operator's monitor is instructed to set the front attachment 4 to the first posture (step S4), and the operator operates the operation lever in accordance with this instruction, so that the front attachment 4 is brought to the first posture of FIG. set. When the setting to the first posture is completed, the posture calculation unit 32 outputs the output values xb, xa (first measured values) of the angle sensors 21b, 21a and the design values Ib, Ia (first reference) in the first posture. Deviations ΔIb and ΔIa (offset values) from the values (step S6). If the deviations ΔIb, ΔIa are smaller than the limit values LΔIb, LΔIa, the deviation ΔIb, ΔIa is stored and the calibration operation is continued. If the deviations ΔIb, ΔIa are greater than the limit values LΔIb, LΔIa, a warning is generated and the calibration The work is finished (step S9, step S8). Thereby, the worker can recognize the malfunction of the sensor itself, and can ensure the accuracy of the sensors 21b and 21a mounted on the work machine.

  When the deviation is stored in the first position, the operator's monitor is instructed to set the front attachment 4 to the second position (step S11), and the worker follows the instruction to move the front attachment 4 to the second position in FIG. Set to posture. Then, the operator actually measures the boom height and the arm height according to instructions from the monitor, and inputs the actual measurement values Hbm and Ham by key operation of the terminal device 20. The second posture may be an arbitrary posture, but in order to make the actual measurement of the height easy, it is preferable that the second posture is a state in which the boom height and the arm height are made as low as possible.

  When the actual boom height value Hbm is input, the posture calculation unit 32 adjusts the gain of the angle sensor 21b. That is, the gain is corrected so that the deviation ΔHb between the boom height detection value Hb (second reference value) obtained from the sensor output value xb and the actual measurement value Hbm (second actual measurement value) is smaller than the allowable value Eb. The value ΔAb is automatically adjusted (steps S19 to S22). In this case, gain adjustment is performed only when the deviation ΔHb is smaller than the limit value LΔHb, and when the deviation ΔHb is greater than or equal to the limit value LΔHb, a warning is generated and the operation is terminated (step S18). As a result, the gain adjustment amount is limited, and only a highly reliable sensor can be used.

  In addition, when the actual arm height value Ham is input, the posture calculation unit 32 adjusts the gain of the angle sensor 21a. That is, the gain is corrected so that the deviation ΔHa between the arm height detection value Ha (second reference value) obtained from the sensor output value xa and the actual measurement value Ham (second actual measurement value) is smaller than the allowable value Ea. The value ΔAa is automatically adjusted (steps S37 to S40). In this case, gain adjustment is performed only when the deviation ΔHa is smaller than the limit value LΔHa, and when the deviation ΔHa is greater than or equal to the limit value LΔHa, a warning is generated and the operation is terminated (step S36). As a result, the gain adjustment amount is limited, and only a highly reliable sensor can be used.

  Through the above calibration work, output characteristic correction values ΔI and ΔA are stored in the storage device 12. Thereafter, the posture calculation unit 32 obtains the detected values of the boom angle yb and the arm angle ya based on the stored output characteristics. Thereby, the boom angle yb and the arm angle ya can be obtained with high accuracy. Therefore, the vehicle body control unit 33 can satisfactorily perform trajectory control, overload prevention control, and the like.

According to the present embodiment, the following effects can be achieved.
(1) Based on the design output characteristics of the sensors 21a and 21b, the design values Ia and Ib of the sensor output in the first posture are set, and the design values Ia and Ib (first reference values) and the sensor output value xb , xa (first measured value) and deviations ΔIa and ΔIb are obtained. Further, the boom height and the arm height in the second posture are detected based on the outputs of the sensors 21a, 21b and the design output characteristics, and the detected values Hbm, Ham (second reference value) and measured values Hb, Ha ( Deviation from the second measured value) was obtained. The design output characteristics are corrected based on these deviations. Thus, the angle sensors 21b and 21a can be calibrated in consideration of the design output characteristics, and the reliability of the detection values of the sensors 21a and 21b is increased.

(2) Focusing on the fact that the design output characteristic is uniquely determined from the offset and gain, the offset correction amount ΔI of the design output characteristic is calculated in the first posture, and the gain correction amount ΔA is calculated in the second posture. Therefore, the design output characteristics can be easily corrected.
(3) Limit values LΔIb, LΔIa, LΔHb, LΔHa of deviations ΔIb, ΔIa in the first posture and deviations ΔHb, ΔHa in the second posture are set, and the calibration operation is continued only when the deviation is smaller than the limit value, Since an alarm is generated when the deviation is greater than or equal to the limit value, it is possible to easily grasp a sensor failure or the like.
(4) Since the state where the cylinders 7b and 7a are expanded and contracted to the stroke end is the first posture, the design values Ia and Ib of the sensor output corresponding to the known angles are obtained without actually measuring the boom angle and the arm angle. It can be obtained and calibration work is easy.
(5) Since the boom height Hbm and the arm height Ham are actually measured in the second posture, the state where the cylinders 7b and 7a are arbitrarily expanded and contracted can be set as the second posture. Therefore, it is not necessary to extend and retract the cylinders 7b and 7a to the stroke ends on both sides, and the calibration work can be performed without being restricted by the work place.
(6) Since the deviation between the boom height and the arm height is obtained in the second posture, it is easier and more accurate to measure the boom height and the arm height than to measure the boom angle and the arm angle. Yes, the output characteristics can be corrected with high accuracy.
(7) Since the procedure of the calibration work is displayed on the monitor, the operator only needs to perform the work according to the instruction of the monitor, and the calibration work can be performed easily and accurately.
(8) Since the terminal device 20 detachably attached to the controller 10 is provided and the calibration work is performed by the input from the terminal device 20, the terminal device 20 is removed during the normal operation, and the sensors 21a and 21b are mistakenly connected. Calibration is never performed.
(9) At the time of the calibration processing in the posture calculation unit 32, the boom angle sensor 21b is first calibrated (FIG. 5), and the arm angle sensor 21a is calibrated using this correction result (FIG. 6). The sensors 21b and 21a can be calibrated efficiently.

  In the above embodiment, the state in which the cylinders 7b and 7a are expanded and contracted to the stroke end is the first posture. However, the design values Ib and Sb of the sensors 21b and 21a corresponding to the known boom angle and arm angle are used. Any posture other than those described above may be used as the first posture as long as Ia can be grasped. That is, the state in which the cylinders 7b and 7a are arbitrarily expanded and contracted is defined as the first posture, the boom angle and the arm angle are measured in the first posture, and the sensor output design value Ib, Ia may be obtained from the design output characteristics, and the deviation between the output values xb, xa of the sensors 21b, 21a and the design values Ib, Ia may be obtained.

  In the first posture, deviations ΔIb and ΔIa between the output values xb and xa of the sensors 21b and 21a and the design values Ib and Ia are obtained, and in the second posture, the deviations ΔHb and ΔHa are obtained with respect to the boom height and the arm height. However, if the design output characteristics are corrected according to the deviation between the reference values in the first attitude and the second attitude determined based on the design output characteristics and the actually measured values corresponding to the reference values. For example, the physical quantity of the reference value is not limited to that described above. For example, the deviation between the reference value and the actual measurement value may be obtained for the boom angle and the arm angle or the boom radius and the arm radius, and the design output characteristics may be corrected according to the deviation. That is, the processing in the posture calculation unit 32 as the correction unit is not limited to the above.

  In the above description, the front attachment 4 is rotated by the cylinders 7b and 7a, but may be rotated by other rotating means. As the storage device 12 as the storage means, a RAM, a flash memory, a small hard disk, a nonvolatile memory such as an EEPROM, or the like can be used. An alarm message is output from the monitor when the deviations ΔIb, ΔIa, ΔHb, ΔHa are equal to or greater than a predetermined value. However, the type of alarm as alarm means is not limited to this. Although the work procedure is instructed from the monitor during the configuration work, the work procedure may be instructed by voice or the like. That is, the configuration as the instruction unit is not limited to the above.

  In the above description, the calibration of the angle sensors 21b and 21a attached to the base ends of the boom 4b and the arm 4a has been described. However, the calibration of the angle sensors provided on the other rotating members can be similarly performed. Further, the present invention can be applied to other working machines other than the boom working machine. That is, the present invention is not limited to the calibration apparatus according to the embodiment as long as the features and functions of the present invention can be realized.

1 is an external side view of a hydraulic excavator to which the present invention is applied. 1 is a block diagram of a calibration apparatus according to an embodiment of the present invention. The figure which shows the relationship between the design output characteristic of an angle sensor, and its correction value. The flowchart which shows an example of the process regarding calibration of the angle sensor in the attitude | position calculating part of FIG. Continuation of the flowchart of FIG. Continuation of the flowchart of FIG. The figure which shows the 1st attitude | position of a working machine at the time of calibrating an angle sensor. The figure which shows the 2nd attitude | position of a working machine at the time of calibrating an angle sensor.

Explanation of symbols

4 Front Attachment 4b Boom 4a Arm 7b Boom Cylinder 7a Arm Cylinder 10 Controller 12 Storage Device 20 Terminal Device 21b Boom Angle Sensor 21a Arm Angle Sensor 31b Boom Angle Conversion Unit 31a Arm Angle Conversion Unit 32 Attitude Calculation Unit

Claims (5)

An angle sensor that is provided on a rotatable rotation member and detects a rotation angle of the rotation member;
Storage means for storing design output characteristics indicating a relationship between an output signal of the angle sensor and a detection angle corresponding to the output signal;
Rotating means for rotating the rotating member to a first attitude and a second attitude;
Deviation between the first reference value determined based on the design output characteristic in the first posture and the first measured value corresponding to the reference value, and determined based on the design output characteristic in the second posture. A correction device for an angle sensor, comprising: correction means for correcting the design output characteristic according to a deviation between a second reference value and a second actual measurement value corresponding to the reference value. The angle sensor calibration device according to claim 1,
The correction means offsets the design output characteristic according to a deviation between the first reference value and the first actually measured value in the first attitude, and the second reference value in the second attitude A calibration device for an angle sensor, wherein the gain of the output characteristic after the offset is changed in accordance with a deviation from the second actual measurement value. In the angle sensor calibration device according to claim 1 or 2,
The first attitude corresponds to a maximum rotation position of the rotation member, and the second attitude corresponds to an arbitrary rotation position of the rotation member. . In the angle sensor calibration device according to claim 1 or 2,
An angle sensor calibration apparatus, further comprising alarm means for generating an alarm when the deviation exceeds a predetermined value. In the calibration apparatus of the angle sensor of any one of Claims 1-4,
An angle sensor calibration apparatus, further comprising instruction means for instructing a procedure of calibration work.

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