Output value correction device for acceleration sensor, output value correction method for acceleration sensor, optical axis control device for vehicle lamp, and vehicle lamp system

Abstract

The present invention corrects an offset in the output value of an acceleration sensor with a simple configuration.　This output value correction device for an acceleration sensor includes a controller and a memory. The memory stores a data group of pairs of a first acceleration and a second acceleration acquired from an acceleration sensor at a plurality of timings when the acceleration sensor is stationary. The controller: acquires first data comprising a pair of the first acceleration and the second acceleration from the acceleration sensor; extracts, from the data group stored in the memory, second data in which the magnitude of the second acceleration is substantially the same as that of the first data but the sign of the first acceleration is opposite; determines an intermediate value between the first acceleration of the first data and the first acceleration of the second data; and corrects the value of the first acceleration output from the acceleration sensor by using the intermediate value as a correction value.

Description

Acceleration sensor output value correction device, acceleration sensor output value correction method, vehicle lamp optical axis control device, and vehicle lamp system

[0001] The present disclosure relates to an acceleration sensor output value correction device, an acceleration sensor output value correction method, a vehicle lamp optical axis control device, and a vehicle lamp system.

[0002] Japanese Patent No. 6873347 (Patent Document 1) describes an optical axis control device that measures a first road surface tilt angle by integrating the amount of change in the horizontal plane tilt angle while the vehicle is stopped, and measures a second road surface tilt angle based on the ratio of the amount of change in acceleration in the up-down direction to the amount of change in acceleration in the forward-backward direction while the vehicle is moving, derives a regression line in an orthogonal coordinate system having a first axis corresponding to the first road surface tilt angle and a second axis corresponding to the second road surface tilt angle, and corrects the first road surface tilt angle so as to cancel the offset amount of the regression line.

[0003] The above-mentioned prior art has room for improvement in that it takes a relatively long time to accumulate data to obtain a regression line, and the calculations required to obtain the regression line consume a large amount of hardware and software resources.

[0004] Patent No. 6873347

[0005] One object of a specific aspect of the present disclosure is to provide a technique capable of correcting the output value of an acceleration sensor with a simple configuration.

[0006] [1] An output value correction device for an acceleration sensor according to one aspect of the present disclosure is a device for correcting acceleration output from an acceleration sensor capable of detecting accelerations corresponding to a first axis and a second axis that are orthogonal to each other, the device including: a controller; and a memory connected to the controller, wherein the memory stores a data group of pairs of the accelerations obtained from the acceleration sensor at multiple times while the acceleration sensor is stationary, the data group being a first acceleration corresponding to the first axis and a second acceleration corresponding to the second axis, the first acceleration and the second acceleration being obtained at multiple times while the acceleration sensor is stationary, the controller: obtains first data which is a pair of the first acceleration and the second acceleration from the acceleration sensor, extracts second data from the data group stored in the memory, the second data having substantially the same magnitude as the first data and the second acceleration but having an opposite sign to the first acceleration, determines an intermediate value between the first acceleration of the first data and the first acceleration of the second data, and corrects the value of the first acceleration output from the acceleration sensor using the intermediate value as a correction value. [2] An acceleration sensor output value correction device according to one aspect of the present disclosure is a device for correcting acceleration output from an acceleration sensor capable of detecting accelerations corresponding to a first axis and a second axis that are orthogonal to each other, the device including: a controller; and a memory connected to the controller, wherein the memory stores a data group of pairs of accelerations obtained from the acceleration sensor at multiple times while the acceleration sensor is stationary, the data group being a first acceleration corresponding to the first axis and a second acceleration corresponding to the second axis, the first acceleration being the first acceleration and the second acceleration being the second axis, and the controller extracts, from the data group stored in the memory, first data and second data in which the magnitude of the second acceleration is substantially the same and the signs of the first acceleration are opposite to each other, calculates an intermediate value between the first acceleration of the first data and the first acceleration of the second data, and corrects the value of the first acceleration output from the acceleration sensor using the intermediate value as a correction value.[3] A vehicle lamp optical axis control device according to one aspect of the present disclosure is a vehicle lamp optical axis control device including: the acceleration sensor output value correction device according to 1 or 2, the acceleration sensor, and an optical axis control unit that variably sets the optical axis of the vehicle lamp using the acceleration of the acceleration sensor corrected by the output value correction device. [4] A vehicle lamp system according to one aspect of the present disclosure is a vehicle lamp system that includes: the optical axis control device according to 3, and a vehicle lamp whose optical axis is set by the optical axis control device. [5] A method for correcting an output value of an acceleration sensor according to one aspect of the present disclosure is a method executed using a controller and a memory to correct an acceleration output from an acceleration sensor capable of detecting accelerations corresponding to a first axis and a second axis that are orthogonal to each other, wherein the memory stores a data group of pairs of accelerations obtained from the acceleration sensor at multiple times while the acceleration sensor is stationary, the data group being a first acceleration corresponding to the first axis and a second acceleration corresponding to the second axis, and the controller performs the following operations: obtains first data which is a pair of the first acceleration and the second acceleration from the acceleration sensor; extracts second data from the data group stored in the memory, the second data having the same magnitude as the first data and the second acceleration but having an opposite sign to the first acceleration; calculates an intermediate value between the first acceleration of the first data and the first acceleration of the second data; and corrects the value of the first acceleration output from the acceleration sensor using the intermediate value as a correction value.[6] An acceleration sensor output value correction method according to one aspect of the present disclosure is a method executed using a controller and a memory to correct accelerations output from an acceleration sensor capable of detecting accelerations corresponding to a first axis and a second axis that are orthogonal to each other, wherein the memory stores a data group of pairs of accelerations obtained from the acceleration sensor at multiple times while the acceleration sensor is stationary, the data group being a first acceleration corresponding to the first axis and a second acceleration corresponding to the second axis, and the controller executes the following operations: extracting, from the data group stored in the memory, first data and second data in which the magnitude of the second acceleration is the same and the signs of the first acceleration are opposite to each other; determining an intermediate value between the first acceleration of the first data and the first acceleration of the second data; and correcting the value of the first acceleration output from the acceleration sensor using the intermediate value as a correction value.

[0007] According to the above configuration, a technique is provided that can correct the output value of the acceleration sensor with a simple configuration.

[0008] Fig. 1(A) is a diagram showing the configuration of a vehicle lighting system according to an embodiment. Fig. 1(B) is a diagram showing an example of the configuration of a computer system. Fig. 2 is a diagram showing a schematic configuration example of a headlamp. Fig. 3 is a diagram showing the detection state of an acceleration sensor in an ideal state in which the origin does not move. Fig. 4 is a diagram showing the detection state of an acceleration sensor in a state in which the origin moves. Fig. 5 is a flowchart showing the operation procedure of the vehicle lighting system.

[0009] 1(A) is a diagram showing the configuration of a vehicle lighting system according to one embodiment. The vehicle lighting system shown in the figure is mounted on a vehicle, which is an example of a moving body, and includes a light axis control device 1 and a headlamp 2 connected to the light axis control device 1. Information indicating the vehicle speed (vehicle speed information 3) detected by a vehicle speed sensor (not shown) provided on the vehicle is input to the light axis control device 1.

[0010] The optical axis control device 1 controls the variably setting of the illumination state and optical axis of the light emitted by the headlamp 2, and is configured to include a vehicle stop detection unit 10, an acceleration sensor 11, a controller 12, and a storage unit 13. The controller 12 is connected to each of the vehicle stop detection unit 10, the acceleration sensor 11, and the storage unit 13. In this embodiment, an "acceleration sensor output value correction device" is configured to include at least the controller 12 and the storage unit 13.

[0011] The vehicle stop detection unit 10 detects whether the vehicle is stopped or moving. For example, based on vehicle speed information, the vehicle stop detection unit 10 detects that the vehicle is stopped when the vehicle speed is 0, and detects that the vehicle is moving when the vehicle speed is greater than 0. In this embodiment, the vehicle being stopped corresponds to the "acceleration sensor being stationary."

[0012] The acceleration sensor 11 is a sensor configured to be able to detect acceleration in, for example, three mutually orthogonal axial directions, and is installed inside the vehicle. In this embodiment, the acceleration sensor 11 is arranged such that one of the three axes, an X-axis (first axis), corresponds to the longitudinal direction of the vehicle, and the other, a Y-axis (second axis), corresponds to the vertical direction of the vehicle. That is, the Y-axis is arranged to correspond to the vertical direction when the vehicle is not tilted, and the X-axis is arranged to correspond to the horizontal direction (a direction perpendicular to the vertical direction) when the vehicle is not tilted.

[0013] It should be noted that the term "arranged in correspondence" here does not necessarily mean that the X-axis and Y-axis are strictly aligned with the longitudinal or vertical directions of the vehicle. It means that even if there is a misalignment between the X-axis and Y-axis and the longitudinal or vertical directions of the vehicle, the misalignment can be corrected on the controller 12 side, and as a result, the acceleration in the longitudinal or vertical directions of the vehicle can be detected based on the output of the X-axis and Y-axis of the acceleration sensor 11.

[0014] The controller 12 controls the light irradiation by the headlamp 2 and the optical axis at that time. The controller 12 can be configured using a computer system including a processor (CPU: Central Processing Unit) 201, a ROM (Read Only Memory) 202, a RAM (Random Access Memory) 203, a storage device 204 such as a flash memory, an input / output interface (I / F) 205, and the like, as shown in Fig. 1(B) for example.

[0015] The controller 12 includes an offset calculation unit (offset calculation function) 20, a data update unit (data update function) 21, and a control signal generation unit (control signal generation function) 22, which are functions realized when the program 206 stored in the storage device 204 is read and executed by the processor 201.

[0016] The offset calculation unit 20 calculates an offset value, which is a correction value for offsetting the amount of movement when the origin of the three axes of the acceleration sensor 11 moves from its original position due to aging, etc. A specific method for calculating the offset value will be described later.

[0017] The data update unit 21 acquires the X-axis acceleration and the Y-axis acceleration output from the acceleration sensor 11 at multiple times while the vehicle is stopped, and writes and stores data pairs including the X-axis acceleration and the Y-axis acceleration in the storage unit 13. The X-axis acceleration and the Y-axis acceleration of the acceleration sensor 11 are acquired, for example, every 100 milliseconds, and written as data pairs in the storage unit 13. A data group including multiple data pairs written and accumulated in the storage unit 13 in this manner is referred to as a "past log" in this specification. The data update unit 21 also acquires an offset value calculated by the offset calculation unit 20, and writes and stores the offset value in the storage unit 13. The offset value stored in the storage unit 13 is rewritten by the data update unit 21 each time a new offset value is calculated by the offset calculation unit 20.

[0018] The control signal generation unit (optical axis control unit) 22 calculates an attitude angle based on the output values ​​(output data) of the X-axis acceleration and the Y-axis acceleration output from the acceleration sensor 11, generates a control signal for controlling the optical axis of the light emitted by the headlamp 2 according to this attitude angle, and supplies (outputs) it to the headlamp 2. The control signal generation unit 22 of this embodiment has a function of correcting the acceleration obtained from the acceleration sensor 11 using the offset value calculated by the offset calculation unit 20 and stored in the storage unit 13, and calculates the attitude angle using the corrected acceleration. The control signal generation unit 22 also generates a control signal for controlling the operation of the light source 31 of the headlamp 2, and supplies (outputs) it to the light source 31.

[0019] The storage unit 13 is a non-volatile memory such as a flash memory, and stores data sets and offset values ​​required for information processing in the controller 12. The data sets stored in the storage unit 13 are rewritten as appropriate by a data update unit 21 of the controller 12.

[0020] The headlamp 2 is attached to the front of the vehicle and emits light such as high beam and low beam ahead of the vehicle. The headlamp 2 includes a light source 31 that emits light and a drive mechanism 32 that adjusts the optical axis of the light emitted by the light source 31.

[0021] 2 is a diagram schematically illustrating an example configuration of a headlamp 2. The headlamp 2 of this embodiment, as an example, includes a light source 31, a drive mechanism 32, a housing 33 that houses the light source 31, and a lens 34 that is disposed in front of the light source 31 (in the direction in which light is emitted) and fixed to the housing 33. The inner surface of the housing 33 is provided with a reflective surface that reflects light from the light source 31 forward.

[0022] The drive mechanism (actuator) 32 is connected to a housing 33 that houses the light source 31, and changes the attitude of this housing 33. This makes it possible to variably set the optical axis a of the light from the light source 31. For example, when the rear of the vehicle is relatively lowered, the optical axis a is controlled to point downward, and when the front of the vehicle is relatively lowered, the optical axis a is controlled to point upward. In this case, the degree to which the optical axis a points downward or upward is set according to the attitude angle.

[0023] 3 is a diagram showing the detection state of the acceleration sensor in an ideal state where the origin does not move. However, consider the case where the vehicle is stopped. In the following, the vehicle attitude angle (body angle) is defined as θ. Regarding the sign of the attitude angle θ, a value when the vehicle is in a forward-leaning attitude (a state in which the front side is relatively lowered) is defined as positive, and a value when the vehicle is in a backward-leaning attitude (a state in which the rear side is relatively lowered) is defined as negative.

[0024] In this case, if the gravitational acceleration is G, the X-axis acceleration of the acceleration sensor 11 is X, and the Y-axis acceleration is Y, then these can be expressed as follows: X=G sin(θ) or X sin(-θ) Y=G cos(θ)

[0025] Therefore, θ can be calculated as follows: atan represents the arc tangent. θ = atan(X / Y)

[0026] Based on the above relational expression, the attitude angle can be obtained using the X-axis acceleration and Y-axis acceleration of the acceleration sensor 11.

[0027] 4 is a diagram showing the detection state of the acceleration sensor when the origin is shifted. However, consider the case where the vehicle is stopped. In this case, the origin has shifted by α in the X-axis direction and by β in the Y-axis direction from the position in the ideal state. Therefore, if the acceleration output from the acceleration sensor 11 is used as is, the attitude angle θ cannot be calculated accurately.

[0028] Here, when the Y-axis acceleration is a certain value while the vehicle is stopped (i.e., while the acceleration sensor 11 is stationary), the attitude angle θ that can be taken on for this Y-axis acceleration value has the same absolute value and is either a positive value or a negative value. In this case, if the X-axis acceleration corresponding to a positive value of the attitude angle θ is X1 and the X-axis acceleration corresponding to a negative value of the attitude angle θ is X2, the midpoint between X1 and X2, (X1 + X2) / 2, corresponds to the movement amount α in the X-axis direction. Therefore, this movement amount α can be used as an offset value and subtracted from the X-axis acceleration output from the acceleration sensor 11 to correct the movement amount α.

[0029] Specifically, the movement amount α can be calculated as follows: (X1+X2) / 2=((Gsinθ+α)+(Gsin(−θ)+α)) / 2=α

[0030] Therefore, in this embodiment, an offset value corresponding to the movement amount α is calculated by using a "past log," which is a group of acceleration data from the acceleration sensor 11 stored in advance in the storage unit 13, and calculating the midpoint between the X-axis accelerations using two pieces of data in which the Y-axis accelerations are equal and the X-axis accelerations have opposite signs but the same absolute value. The calculated offset value is stored in the storage unit 13. Next, when a new offset value is obtained, the data update unit 21 updates the offset value stored in the storage unit 13. Then, when the attitude angle θ is calculated by the control signal generation unit 22, a correction is made by subtracting the offset value from the X-axis acceleration output from the acceleration sensor, and the attitude angle θ is calculated using the corrected acceleration, thereby improving the calculation accuracy of the attitude angle θ and achieving high-precision optical axis control.

[0031] 5 is a flowchart showing the operation procedure of the vehicle lighting system. Here, the operation procedure for calculating and updating the offset value is explained. It is assumed that the past logs are accumulated in advance and stored in the memory unit 13. The order of the processes shown here can be changed as long as no contradictions or inconsistencies occur in the results of the information processing, and other processes not explicitly shown here can also be added.

[0032] When the vehicle stop detection unit 10 detects that the vehicle is stopped (step S11; YES), the offset calculation unit 20 of the controller 12 acquires a pair of X-axis acceleration and Y-axis acceleration (first data) output from the acceleration sensor 11 (step S12).

[0033] Next, the offset calculation unit 20 searches the past logs, which are a group of data stored in the memory unit 13, and if there is a data pair (second data) that includes a Y-axis acceleration that is equal to (substantially the same in magnitude as) the Y-axis acceleration of the first data acquired in step S12 (step S13; YES), it extracts the X-axis acceleration included in the second data.

[0034] Note that here, the Y-axis acceleration may be strictly equal, or may be substantially equal within a certain tolerance range. That is, if the difference between the acquired Y-axis acceleration and the Y-axis acceleration retrieved from the past log is within ±2 mG, the Y-axis accelerations may be considered to be substantially equal within the tolerance range.

[0035] If the sign of the X-axis acceleration of the extracted second data is different from the sign of the X-axis acceleration of the first data acquired in step S11, i.e., if both a positive X-axis acceleration and a negative X-axis acceleration are obtained (step S14), the offset calculation unit 20 calculates the midpoint using those X-axis accelerations (corresponding to the above-mentioned X1 and X2) (step S15). This calculated midpoint corresponds to the above-mentioned movement amount α, i.e., the offset value.

[0036] The data updating unit 21 writes the determined offset value into the storage unit 13, i.e., performs an offset value update process (step S16). Since the offset value is updated as needed in this manner, the control signal generating unit 22 calculates the attitude angle θ using the acceleration corrected using the offset value stored in the storage unit 13, thereby improving the accuracy of the attitude angle θ and thus improving the accuracy of the optical axis control.

[0037] If the vehicle is not stopped (step S11; NO), if there is no data pair in the past log that contains a Y-axis acceleration value equal to the Y-axis acceleration obtained in step S12 (step S13; NO), or if an X-axis acceleration with a different sign has not been obtained (step S14; NO), the offset value is not updated and the process returns to step S11.

[0038] According to the above-described embodiment, a technique is provided that can correct the output value of the acceleration sensor with a simple configuration. Furthermore, by using the corrected acceleration, the accuracy of calculating the vehicle attitude angle can be improved, thereby improving the accuracy of optical axis control.

[0039] The present disclosure is not limited to the above-described embodiment, and various modifications can be made within the scope of the gist of the present disclosure. For example, in the above-described embodiment, the offset value is calculated using the Y-axis acceleration acquired at a certain time while the vehicle is stopped and the Y-axis acceleration and the past log. However, the timing of calculating the offset value is not limited to this. For example, at an appropriate time while the vehicle is stopped, data pairs having the same Y-axis acceleration but different signs for the X-axis acceleration may be extracted from the past logs accumulated up to that point, and the offset value may be calculated using the X-axis acceleration of the data pairs.

[0040] In the above-described embodiment, the optical axis control device for a vehicle lamp and the vehicle lamp system including the same were described as examples to which the acceleration sensor output value correction device according to the present disclosure can be applied. However, the scope of application of the acceleration sensor output value correction device according to the present disclosure is not limited thereto. The acceleration sensor output value correction device according to the present disclosure can be applied to any device, equipment, or system that incorporates an acceleration sensor and whose posture can change (i.e., any moving object). Various application examples are conceivable, such as drive recorders, portable game devices, navigation devices, and smartphones.

[0041] The present disclosure has the following features: (Supplementary Note 1) An apparatus for correcting acceleration output from an acceleration sensor capable of detecting accelerations corresponding to a first axis and a second axis that are orthogonal to each other, comprising: a controller; and a memory connected to the controller, wherein the memory stores a data group of pairs of the accelerations obtained from the acceleration sensor at multiple times while the acceleration sensor is stationary, the data group being a first acceleration corresponding to the first axis and a second acceleration corresponding to the second axis, the first acceleration and the second acceleration being paired, the controller obtains first data of the pair of the first acceleration and the second acceleration from the data group stored in the memory, extracts second data of the first acceleration and the second acceleration having substantially the same magnitude but opposite in sign to the first acceleration, determines an intermediate value between the first acceleration of the first data and the first acceleration of the second data, and corrects the value of the first acceleration output from the acceleration sensor using the intermediate value as a correction value. (Supplementary Note 2) An apparatus for correcting acceleration output from an acceleration sensor capable of detecting accelerations corresponding to first and second axes orthogonal to each other, comprising: a controller; and a memory connected to the controller, wherein the memory stores a data group of pairs of accelerations obtained from the acceleration sensor at multiple times while the acceleration sensor is stationary, each pair comprising a first acceleration corresponding to the first axis and a second acceleration corresponding to the second axis, the pair of accelerations being the first acceleration and the second acceleration, the first acceleration being substantially the same in magnitude and opposite in sign to each other, from the data group stored in the memory, calculates an intermediate value between the first acceleration of the first data and the first acceleration of the second data, and corrects the value of the first acceleration output from the acceleration sensor using the intermediate value as a correction value. (Supplementary Note 3) The apparatus for correcting output values ​​of an acceleration sensor according to Supplementary Note 1 or 2, wherein the controller stores the correction value in the memory.(Supplementary Note 4) The output value correction device for an acceleration sensor according to any of Supplements 1 to 3, wherein the controller updates the correction value stored in the memory when a new correction value is obtained. (Supplementary Note 5) The output value correction device for an acceleration sensor according to any of Supplements 1 to 4, wherein the acceleration sensor is installed on a moving body, and the first axis is arranged to correspond to a direction perpendicular to a vertical direction when the moving body is not tilted, and the second axis is arranged to correspond to the vertical direction. (Supplementary Note 6) The output value correction device for an acceleration sensor according to any of Supplements 1 to 5, wherein the moving body is a vehicle. (Supplementary Note 7) A beam axis control device for a vehicle lamp, comprising: the output value correction device for an acceleration sensor according to any of Supplements 1 to 6, an acceleration sensor, and a beam axis control unit that variably sets the beam axis of a vehicle lamp using the acceleration of the acceleration sensor corrected by the output value correction device. (Supplementary Note 8) A vehicle lighting system comprising: the optical axis control device according to Supplementary Note 7; and a vehicle lighting device in which the optical axis is set by the optical axis control device. (Supplementary Note 9) A method executed using a controller and a memory for correcting the acceleration output from an acceleration sensor capable of detecting accelerations corresponding to each of a first axis and a second axis which are orthogonal to each other, wherein the memory stores a data group of pairs of a first acceleration corresponding to the first axis and a second acceleration corresponding to the second axis, the accelerations being acquired from the acceleration sensor at multiple times while the acceleration sensor is stationary, and the controller executes the following operations: acquire first data which is a pair of the first acceleration and the second acceleration from the acceleration sensor; extract second data which has the same magnitude as the first data and the second acceleration but has an opposite sign to the first acceleration from the data group stored in the memory; determine an intermediate value between the first acceleration of the first data and the first acceleration of the second data; and correct the value of the first acceleration output from the acceleration sensor using the intermediate value.(Supplementary Note 10) A method executed using a controller and a memory for correcting acceleration output from an acceleration sensor capable of detecting accelerations corresponding to a first axis and a second axis which are orthogonal to each other, wherein the memory stores a data group of pairs of a first acceleration corresponding to the first axis and a second acceleration corresponding to the second axis, the pair of accelerations being acquired from the acceleration sensor at multiple times while the acceleration sensor is stationary, and the controller executes the following steps: extracting, from the data group stored in the memory, first data and second data in which the magnitude of the second acceleration is the same and the signs of the first acceleration are opposite to each other; determining an intermediate value between the first acceleration of the first data and the first acceleration of the second data; and correcting the value of the first acceleration output from the acceleration sensor using the intermediate value as a correction value.

[0042] 1: Optical axis control device, 2: Headlight, 3: Vehicle speed information, 10: Vehicle stop detection unit, 11: Acceleration sensor, 12: Controller, 13: Storage unit, 20: Offset calculation unit, 21: Data update unit, 22: Control signal generation unit

Claims

1. An apparatus for correcting the acceleration output from an acceleration sensor capable of detecting the acceleration corresponding to each of the orthogonal first axis and second axis, comprising: a controller; and a memory connected to the controller, wherein the memory stores a data group of pairs of a first acceleration corresponding to the first axis and a second acceleration corresponding to the second axis, which are the accelerations acquired from the acceleration sensor at a plurality of timings during the rest of the acceleration sensor, and the controller acquires first data which is a pair of the first acceleration and the second acceleration from the acceleration sensor, extracts second data from the data group stored in the memory, wherein the magnitude of the second acceleration is substantially the same as that of the first data and the sign of the first acceleration is opposite, obtains a median value between the first acceleration of the first data and the first acceleration of the second data, and corrects the value of the first acceleration output from the acceleration sensor using the median value as a correction value. An acceleration sensor output value correction apparatus.

2. An apparatus for correcting the acceleration output from an acceleration sensor capable of detecting the acceleration corresponding to each of the orthogonal first axis and second axis, comprising: a controller; and a memory connected to the controller, wherein the memory stores a data group of pairs of a first acceleration corresponding to the first axis and a second acceleration corresponding to the second axis, which are the accelerations acquired from the acceleration sensor at a plurality of timings during the rest of the acceleration sensor, and the controller extracts first data and second data from the data group stored in the memory, wherein the magnitude of the second acceleration is substantially the same and the signs of the first accelerations are opposite to each other, obtains a median value between the first acceleration of the first data and the first acceleration of the second data, and corrects the value of the first acceleration output from the acceleration sensor using the median value as a correction value. An acceleration sensor output value correction apparatus.

3. The acceleration sensor output value correction apparatus according to claim 1 or 2, wherein the controller stores the correction value in the memory.

4. The acceleration sensor output value correction apparatus according to claim 1 or 2, wherein the controller updates the correction value stored in the memory when the correction value is newly obtained.

5. The acceleration sensor is installed in a moving body, and the first axis is arranged corresponding to a direction orthogonal to the vertical direction when the moving body is in a non-tilted state, and the second axis is arranged corresponding to the vertical direction. An output value correction device for the acceleration sensor according to claim 1 or 2.

6. The moving body is a vehicle. An output value correction device for the acceleration sensor according to claim 1 or 2.

7. An optical axis control device for a vehicle lamp, comprising: the output value correction device for the acceleration sensor according to claim 1 or 2; an acceleration sensor; and an optical axis control unit that variably sets the optical axis of the vehicle lamp using the acceleration of the acceleration sensor corrected by the output value correction device.

8. A vehicle lamp system, comprising: the optical axis control device according to claim 7; and a vehicle lamp whose optical axis is set by the optical axis control device.

9. A method executed using a controller and a memory to correct the acceleration output from an acceleration sensor capable of detecting the acceleration corresponding to each of the orthogonal first axis and second axis, wherein the memory stores a data group of pairs of a first acceleration corresponding to the first axis and a second acceleration corresponding to the second axis, which are the accelerations obtained from the acceleration sensor at a plurality of timings during the rest of the acceleration sensor, and the controller: obtains first data, which is a pair of the first acceleration and the second acceleration, from the acceleration sensor; extracts second data from the data group stored in the memory, wherein the magnitude of the second acceleration is the same as that of the first data and the sign of the first acceleration is opposite; obtains an intermediate value between the first acceleration of the first data and the first acceleration of the second data; and corrects the value of the first acceleration output from the acceleration sensor using the intermediate value as a correction value. An output value correction method for an acceleration sensor.

10. A method executed using a controller and a memory to correct the acceleration output from an acceleration sensor capable of detecting the acceleration corresponding to each of the orthogonal first axis and second axis, wherein the memory stores a data group of pairs of a first acceleration corresponding to the first axis and a second acceleration corresponding to the second axis, which are the accelerations acquired from the acceleration sensor at a plurality of timings during the rest of the acceleration sensor, and the controller extracts first data and second data from the data group stored in the memory, wherein the magnitudes of the second accelerations are the same and the signs of the first accelerations are opposite to each other, obtains a median value between the first acceleration of the first data and the first acceleration of the second data, and corrects the value of the first acceleration output from the acceleration sensor using the median value as a correction value. An acceleration sensor output value correction method for performing the above steps.

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