Vehicle control device

Abstract

To suppress deviation of optical axis control of a head lamp, even when an output value of an acceleration sensor is influenced by deflection of a vehicle by a live load, in a control device for the vehicle for performing the optical axis control of the head lamp by using the acceleration sensor.SOLUTION: The vehicular control apparatus 1 is a vehicular control apparatus having the control section 2a for performing the optical axis control of the headlamp in the vehicle 10 based on the acceleration sensor value outputted from the acceleration sensor 4 mounted in the vehicle 10, wherein the acceleration sensor 4 is mounted at a position where the acceleration sensor value is affected by the deflection due to the movable load, and the control section 2a performs the optical axis control of the headlamp in the vehicle 10 by adding the compensation value A in which the deflection due to the movable load is taken into consideration.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a vehicle control device that controls the optical axes of vehicle headlamps based on an output value from an acceleration sensor mounted on the vehicle. [Background technology]

[0002] Conventionally, there is an auto-leveling control that automatically adjusts the tilt angle of the headlamp optical axis according to the vehicle's inclination angle to prevent dazzling oncoming vehicles. For example, a vehicle lighting control device described in Patent Document 1 derives the sum of the road surface angle and the vehicle's inclination angle based on the output value of an acceleration sensor mounted on the vehicle. Here, the amount of change in the sum while the vehicle is stopped is estimated as the amount of change in the vehicle's inclination angle, and the headlamp optical axis is automatically adjusted according to this amount of change. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-94643 Summary of the Invention [Problem to be solved by the invention]

[0004] In the auto-leveling control using an acceleration sensor as disclosed in Patent Document 1, a change in the vehicle's tilt angle is calculated using the gravity-direction component of the acceleration sensor's detected value. In this case, if the vehicle is loaded with luggage or the like and the part of the vehicle body on which the acceleration sensor is mounted is deflected, the amount of change in the gravity-direction component of the acceleration sensor will include a change due to the actual change in the vehicle's pitch angle and a change due to the deflection of the vehicle body part. As a result, the deflection of the vehicle body will result in an error when calculating the vehicle's tilt angle, which can cause a problem in that the control angle of the headlamp's optical axis will deviate from the angle that should be adjusted.

[0005] One way to mitigate the effects of such bending of the vehicle body is to reinforce the part of the vehicle where the acceleration sensor is mounted to prevent bending. However, changing to a stronger material would increase costs, and changing the thickness of the same material would not only increase costs but also weight.

[0006] Therefore, the present invention aims to realize a vehicle control device that uses an acceleration sensor to control the optical axis of headlights, and that can suppress deviations in the optical axis control of headlights even when the output value of the acceleration sensor is affected by the deflection of the vehicle due to the load, and to realize the vehicle control device with an inexpensive configuration. [Means for solving the problem]

[0007] (1) The vehicle control device of the present invention, which is provided to solve the above-mentioned problems, is a vehicle control device having an optical axis control unit that controls the optical axis of the vehicle's headlamps based on an acceleration sensor value output from an acceleration sensor mounted on the vehicle, wherein the acceleration sensor is mounted at a location where the acceleration sensor value is affected by deflection due to the load, and the optical axis control unit controls the optical axis of the vehicle's headlamps by adding a correction value that takes into account the deflection due to the load.

[0008] In the vehicle control device of the present invention, the optical axis control unit controls the optical axes of the vehicle's headlamps by adding a correction value that takes into account deflection due to the load. In this way, when the optical axis control unit performs headlamp optical axis control, the vehicle control device of the present invention can suppress deviations in optical axis control that occur when the acceleration sensor value is affected by deflection of the vehicle. Furthermore, the vehicle control device of the present invention suppresses deviations in the optical axis during optical axis control even when deflection occurs in the vehicle due to the load, so there is no need to change the material of the portion where deflection occurs to a stronger material or change the thickness to suppress the deviation. Therefore, the vehicle control device of the present invention can suppress deviations in headlamp optical axis control that are caused by the load without increasing costs or vehicle weight. Furthermore, the vehicle control device of the present invention is not restricted to a location where deflection due to the load does not occur, thereby improving the flexibility of the acceleration sensor mounting location.

[0009] (2) The correction value may be set to increase as the pitch angle of the vehicle increases.

[0010] It is assumed that the relationship between the live load and the pitch angle (inclination angle) of the vehicle, and the relationship between the live load and the deflection of the vehicle are both approximately proportional. If this is assumed, when the vehicle pitch angle is small, the vehicle deflection is also small, so the correction value needs to be small. On the other hand, when the pitch angle is large, the vehicle deflection is also large, so the correction value needs to be large. Therefore, the vehicle control device of the present invention further improves the accuracy of light axis control by setting the correction value to increase as the vehicle pitch angle increases.

[0011] (3) The correction value may be set in accordance with the mounting position of the acceleration sensor.

[0012] The deflection of a vehicle due to a load varies depending on the part of the vehicle. Therefore, the vehicle control device of the present invention sets a correction value according to the mounting position of the acceleration sensor, thereby making it possible to perform optical axis control using an appropriate correction value according to the mounting position of the acceleration sensor. This also further improves the accuracy of optical axis control in the vehicle control device of the present invention.

[0013] (4) The correction value may be set to a larger value when the acceleration sensor is mounted on the rear side of the vehicle than when the acceleration sensor is mounted on the front side of the vehicle.

[0014] In this way, the vehicle control device of the present invention can control the headlamp optical axis using more accurate correction values ​​for a vehicle in which the amount of deflection due to load is greater at the rear side than at the front side.

[0015] (5) The acceleration sensor may be mounted directly or indirectly on the floor of the vehicle.

[0016] In this way, the vehicle control device of the present invention can control the optical axis of the headlamp by taking into account a correction value that takes into account the deflection of the vehicle floor.

[0017] The vehicle control device of the present invention may include a vehicle tilt angle deriving unit that derives the vehicle tilt angle. In such a configuration, there is a concern that the vehicle tilt angle derived by the vehicle tilt angle deriving unit may include an error caused by the acceleration sensor value being affected by deflection due to the load, relative to the actual pitch angle of the vehicle.

[0018] (6) Based on the above findings, the vehicle control device of the present invention includes a vehicle tilt angle derivation unit that derives a vehicle tilt angle based on the acceleration sensor value output from the acceleration sensor, the vehicle tilt angle including an error that occurs when the acceleration sensor value is affected by deflection due to a load relative to the actual pitch angle of the vehicle, the correction value corrects the error due to the deflection, and the light axis control unit controls the light axis of the vehicle's headlamp based on the vehicle tilt angle derived by the vehicle tilt angle derivation unit and the correction value.

[0019] By configuring the vehicle control device of the present invention as described above in (6), the vehicle tilt angle derived based on the acceleration sensor value is corrected by the correction value for correcting the error caused by the deflection as described above, and then the vehicle control device of the present invention can perform headlamp optical axis control. In this way, the vehicle control device of the present invention can suppress deviations in optical axis control that occur when the headlamp optical axis control is performed assuming that the vehicle tilt angle derived based on the acceleration sensor value is the actual vehicle pitch angle.

[0020] (7) The vehicle inclination angle derivation unit derives the vehicle inclination angle on the condition that at least the vehicle is stopped, and the light axis control unit controls the light axis of the headlamp based on the vehicle inclination angle derived by the vehicle inclination angle derivation unit and the correction value.

[0021] If the acceleration sensor value changes while the vehicle is moving, it can be assumed that the change is due to a change in road surface angle or a change in vehicle acceleration. On the other hand, if the acceleration sensor value changes while the vehicle is stopped, it can be assumed that the change is due to a change in vehicle inclination angle. Based on this knowledge, the vehicle control device of the present invention derives the vehicle inclination angle under the condition that at least the vehicle is stopped. As a result, when a change occurs in the derived vehicle inclination angle, the vehicle control device of the present invention can control the headlamp beam axis by assuming that the change is due to a change in the vehicle inclination angle. In this way, the vehicle control device of the present invention can derive the vehicle inclination angle without being affected by changes in road surface angle or vehicle acceleration, thereby enabling accurate headlamp beam axis control.

[0022] (8) The condition may further include that the vehicle is stationary and stable.

[0023] Immediately after the vehicle stops, the acceleration sensor value changes due to vehicle vibrations, etc. Therefore, the vehicle tilt angle deriving unit derives the vehicle tilt angle on the condition that the vehicle is stopped in a stable state. In this way, the vehicle control device of the present invention can more accurately control the headlamp beam axis. [Effects of the Invention]

[0024] According to the present invention, in a vehicle control device that uses an acceleration sensor to control the optical axis of a headlamp, a vehicle control device is realized that can suppress deviations in the optical axis control of the headlamp even when the output value of the acceleration sensor is affected by the deflection of the vehicle due to the load, and the vehicle control device can be realized with an inexpensive configuration. [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a block diagram of a vehicle control device according to an embodiment of the present invention; [Figure 2]10A and 10B are diagrams for explaining the difference in the vehicle tilt angle calculated based on the acceleration sensor value when the vehicle is deflected and when the vehicle is not deflected due to a live load. [Figure 3] 10 is a diagram showing a vehicle tilt angle derived from an output value of an acceleration sensor and a control angle of an optical axis at the vehicle tilt angle; FIG. [Figure 4] 10 is a diagram showing the relationship between the vehicle tilt angle calculated based on the output value of the acceleration sensor affected by deflection due to the live load and the actual vehicle tilt angle. FIG. [Figure 5] 4 is a flowchart illustrating an example of an optical axis control process according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0026] Hereinafter, a vehicle control device 1 according to one embodiment of the present invention will be described in detail with reference to the drawings.

[0027] The vehicle control device 1 of this embodiment automatically adjusts (controls) the optical axis of a headlamp according to the tilt angle (pitch angle) of a vehicle 10. The vehicle control device 1 includes an optical axis control ECU 2, a wheel speed sensor 3, an acceleration sensor 4, and a headlamp optical axis adjustment unit 5.

[0028] The wheel speed sensor 3 detects the wheel speed of each wheel of the vehicle 10. The wheel speed sensor 3 outputs the detected wheel speed value to the optical axis control ECU 2.

[0029] The acceleration sensor 4 is, for example, a three-axis acceleration sensor that detects acceleration in the front-rear direction (direction parallel to the traveling direction), left-right direction (vehicle width direction), and up-down direction of the vehicle 10. The acceleration sensor 4 outputs an output value X in the front-rear direction of the vehicle 10 and an output value Z in the up-down direction to the light axis control ECU 2. The acceleration sensor 4 is mounted at a location where the output values ​​X and Z are affected by deflection due to the load of luggage or the like carried on the vehicle 10. For example, in this embodiment, the acceleration sensor 4 is mounted directly or indirectly on the floor (floor panel, etc.) of the vehicle. The acceleration sensor 4 is not limited to a three-axis sensor, and a one-axis or two-axis acceleration sensor can also be used.

[0030] The headlamp optical axis adjusting unit 5 adjusts the optical axis of the headlamp of the vehicle 10 based on a control signal from an optical axis control ECU 2, which will be described later.

[0031] The light axis control ECU 2 derives the tilt angle of the vehicle 10 (vehicle tilt angle) and calculates the control angle when controlling the light axis of the headlamp. The light axis control ECU 2 includes a control unit 2a, a calculation unit 2b, and a storage unit 2c.

[0032] The calculation unit 2b calculates the inclination angle θ of the vehicle 10 with respect to the road surface based on the speed of each wheel of the vehicle 10 output from the wheel speed sensor 3 and the output value output from the acceleration sensor 4. v (vehicle inclination angle), and the inclination angle θ of the road surface on which the vehicle 10 is traveling with respect to the horizontal plane r (Road surface angle) is derived.

[0033] The tilt angle θ of the vehicle 10 calculated by the calculation unit 2b v and the inclination angle θ of the road surface r The calculation of the inclination angle θ of the vehicle 10 can be performed using the techniques described in, for example, Japanese Patent Application Laid-Open Nos. 2023-104163, 2023-154744, 2023-154745, and 2023-101092. v and the inclination angle θ of the road surface r are angles in the pitch direction of the vehicle 10.

[0034] In this embodiment, the calculation unit 2b calculates the inclination angle θ v This is based on the following idea: The forward illumination range of the headlamp is calculated based on the inclination angle θ of the vehicle 10 with respect to the road surface. v Therefore, the headlamp beam axis control aims to adjust for this change and maintain an optimal illumination range. Therefore, the adjustment (control) of the headlamp beam axis is performed based on the change in the inclination angle θ of the vehicle 10. v It is desirable to carry out this process when the inclination angle θ of the vehicle 10 changes. v rarely changes while the vehicle 10 is traveling. Therefore, in this embodiment, the calculation unit 2b calculates the inclination angle θ v Calculate the inclination angle θ v Based on the change in the light axis of the headlamp, the control unit 2a controls the light axis of the headlamp.

[0035] The storage unit 2c stores a control program related to the control of the control unit 2a and various data required for optical axis control.

[0036] The control unit 2a calculates the tilt angle θ of the vehicle 10 calculated by the calculation unit 2b. v The control unit 2a controls the optical axis of the headlamp based on the inclination angle θ of the vehicle 10 calculated by the calculation unit 2b. v Based on this, the control unit 2a calculates the control angle from the initial position of the headlamp optical axis, and transmits a control signal to the headlamp optical axis adjustment unit 5 to change the headlamp optical axis to the calculated control angle. Upon receiving this signal, the headlamp optical axis adjustment unit 5 adjusts the headlamp optical axis to the control angle. In this way, the control unit 2a controls the headlamp optical axis.

[0037] The initial position of the headlamp's optical axis is set under a predetermined environment (e.g., when the vehicle 10 is placed on a horizontal surface, when the vehicle 10 is stopped, etc.) at a vehicle manufacturing factory or the like, and the initial position is stored in the vehicle 10.

[0038] The tilt angle θ of the vehicle 10 calculated by the calculation unit 2bv When the angle θ of the vehicle 10 changes, the control unit 2a calculates the control angle (control angle from the initial position) of the headlamp optical axis according to the changed angle, and similarly transmits a control signal to the headlamp optical axis adjustment unit 5 to perform headlamp optical axis control (optical axis adjustment: auto-leveling control). Note that in this embodiment, the control unit 2a takes into account the calculation error of the calculation unit 2b (inclination angle θ of the vehicle 10) that occurs when the floor of the vehicle 10 is deflected by the load when controlling the headlamp optical axis. v The optical axis control is performed after correcting the calculation error of the optical axis. This correction will be described later.

[0039] The control unit 2a and the calculation unit 2b are configured with a CPU (Central Processing Unit). The storage unit 2c is configured with a ROM (Read Only Memory) and a RAM (Random Access Memory). In this embodiment, the control unit 2a and the calculation unit 2b are configured with a single CPU, but they can also be configured with separate CPUs.

[0040] The configuration of the vehicle control device 1 of this embodiment has been described above. Next, the headlamp optical axis control of the vehicle 10 executed by the optical axis control ECU 2 and the like will be described in detail with reference to Fig. 2 and Fig. 4. In describing the headlamp optical axis control below, first, the error in the vehicle inclination angle calculated by the calculation unit 2b of the optical axis control ECU 2 will be described with reference to Fig. 2. Next, the headlamp optical axis control will be described while explaining a method for correcting the error with reference to Fig. 4.

[0041] 2(a) shows a state in which the vehicle 10 is stopped on a flat road (road surface angle = 0 degrees) with no load. At this time, the vehicle 10 is not inclined relative to the road surface, and the inclination angle θ v will be "0".

[0042] When a heavy object such as luggage is loaded onto the vehicle 10 in the state shown in Fig. 2(a), the vehicle 10 will tilt relative to the road surface. Fig. 2(b) shows a state in which the vehicle 10 is tilted due to luggage being loaded at the rear of the vehicle 10 in the state shown in Fig. 2(a). The calculation unit 2b calculates the tilt angle θ of the vehicle 10 based on the acceleration of the vehicle 10 calculated based on the wheel speed output from the wheel speed sensor 3 in the state shown in Fig. 2(b) and the output value Z output from the acceleration sensor 4. v and the inclination angle θ of the road surface r It is possible to calculate:

[0043] While FIG. 2(b) illustrates a case where the floor of the vehicle 10 does not flex due to the load, as shown in FIG. 2(c), it is also possible that the floor of the vehicle 10 flexes due to the load. In this case, the output value Z of the acceleration sensor 4 changes due to the flexure of the floor of the vehicle 10. Therefore, the tilt angle θ of the vehicle 10 calculated by the calculation unit 2b v The floor deflection also affects the floor.

[0044] For example, as shown in FIG. 2B, when no deflection occurs in the floor of the vehicle 10, the inclination angle θ of the vehicle 10 calculated by the calculation unit 2b is v On the other hand, when the floor of the vehicle 10 is bent as shown in FIG. 2(c), the original inclination angle of the vehicle 10 is v Although the inclination angle θ of the vehicle 10 calculated by the calculation unit 2b is θa, v In other words, the inclination angle θb of the vehicle 10 calculated by the calculation unit 2b in the state of FIG. 2(c) includes an error (|θb-θa|) due to the deflection of the floor of the vehicle 10. Therefore, in FIG. 2(c), the inclination angle θ v If the headlamp optical axis is controlled using θb, the headlamp optical axis will deviate from the angle at which it should be adjusted. Therefore, in this embodiment, the control unit 2a controls the headlamp optical axis by adding a correction value A that takes into account the deflection of the vehicle 10 due to the load.

[0045] (Vehicle tilt angle correction) The pitch angle of the vehicle 10 (inclination angle of the vehicle 10 relative to the road surface) is proportional to the load of luggage and the like carried on the vehicle 10. The amount of deflection of the floor of the vehicle 10 is also proportional to the load. Here, if the inclination angle of the vehicle 10 calculated based on the output value Z of the acceleration sensor 4 is taken as the vertical axis and the actual inclination angle of the vehicle 10 (inclination angle relative to the road surface: pitch angle) is taken as the horizontal axis, the result will be as shown in FIG. 4. In FIG. 4, the inclination angle of the vehicle 10 (G sensor recognized angle) on the vertical axis is proportional to the inclination angle θ of the vehicle 10 calculated by the calculation unit 2b based on the output value Z of the acceleration sensor 4. v On the other hand, the vehicle pitch angle on the horizontal axis is the actual tilt angle of the vehicle 10 measured using a jig or the like.

[0046] 4 shows the ideal relationship between the tilt angle (vertical axis) of the vehicle 10 calculated by the calculation unit 2b when no deflection occurs in the floor of the vehicle 10 and the actual tilt angle (horizontal axis) of the vehicle 10. In other words, since it is ideal for the tilt angle of the vehicle 10 calculated by the calculation unit 2b and the actual tilt angle of the vehicle 10 (pitch angle of the vehicle 10) to be the same, the solid line in FIG. 4 is a straight line with a slope of 1.

[0047] On the other hand, when the floor of the vehicle 10 is bent, the inclination angle θ of the vehicle 10 calculated by the calculation unit 2b is v Since the above-mentioned errors are included in the line, there is a deviation from the solid line in Figure 4. The deviation is shown by the dashed line and the dashed-dotted line in Figure 4.

[0048] For example, the broken line indicates the case where the acceleration sensor 4 is mounted on the front side of the floor of the vehicle 10. Here, each black circle indicates one of the following six loading patterns. That is, the six black circles are arranged in order from the smallest vehicle pitch angle on the horizontal axis: (i) A pattern in which no one is in the vehicle 10 and no luggage is loaded. (ii) A pattern in which only the driver's seat is occupied and no luggage is loaded. (iii) A pattern in which only the front seats (driver's seat and passenger seat) are occupied and no luggage is loaded. (iv) All seats are occupied, and no luggage is loaded. (v) All seats are occupied and 25 kg of luggage is loaded in the trunk. (vi) A pattern in which only the driver's seat is occupied and 250 kg of luggage is loaded in the trunk. For example, the black circle with the largest vehicle pitch angle corresponds to the loading pattern (vi), and the tilt angle θ of the vehicle 10 calculated based on the output value Z output from the acceleration sensor 4 in this loading pattern is v (vertical axis) and the actual vehicle pitch angle (horizontal axis).

[0049] The loading patterns are in the order of (i) to (vi), with increasing load. Therefore, if an approximation line is calculated based on each black circle using, for example, the least squares method, the approximation line will slope upward to the right due to the proportional relationship described above. The approximation line (dashed line) has a slope of, for example, α (α>1). The slope α is a deviation from the ideal slope of 1, and can be considered a calculation error in the tilt angle of the vehicle 10 resulting from deflection of the floor of the vehicle 10 due to the load.

[0050] Therefore, the control unit 2a calculates the tilt angle θ of the vehicle 10 calculated by the calculation unit 2b. v is corrected based on the inclination α. v When the inclination angle θ of the vehicle 10 calculated by the calculation unit 2b is changed, the control unit 2a changes (controls) the optical axis by the same angle as the amount of change. v The correction value A is applied to the control angle calculated based on the above formula to calculate the corrected control angle. Specifically, the tilt angle of the vehicle 10 calculated by the calculation unit 2b is calculated as θ v The control angle calculated based on L The corrected control angle is then revisedθ L In this case, the control unit 2a calculates the revised θ L =θ L× correction value A(1 / α) (Equation (1) to be described later). As a result, the vehicle control device 1 corrects the control angle of the optical axis based on the error that occurs when the output value Z of the acceleration sensor 4 is affected by the deflection of the floor of the vehicle 10, that is, the inclination angle θ of the vehicle 10 calculated by the calculation unit 2b. v and the actual pitch angle of the vehicle 10 can be corrected.

[0051] The dashed line in Fig. 4 indicates the case where the acceleration sensor 4 is mounted on the rear side of the floor of the vehicle 10. Here, like the black circles, the white circles correspond to the loading patterns (i) to (vi) in ascending order of the vehicle pitch angle on the horizontal axis, and the tilt angle θ of the vehicle 10 calculated by the calculation unit 2b for each loading pattern is v The graph shows the relationship between the vehicle tilt angle (vertical axis) and the actual vehicle pitch angle (horizontal axis). If an approximate line is calculated based on each white circle using, for example, the least squares method, the approximate line will slope upward to the right due to the proportional relationship described above. Furthermore, the approximate line (dash-dotted line) has a slope of, for example, β (β<1). The slope β is a deviation from the ideal slope of 1, and can be considered as a calculation error in the tilt angle of the vehicle 10 caused by deflection of the floor of the vehicle 10 due to the load.

[0052] Therefore, when the acceleration sensor 4 is mounted on the rear side of the floor of the vehicle 10, the control unit 2a adjusts the control angle of the headlamp optical axis by the revised θ L =θ L Correction is performed based on the formula: × correction value A(1 / β).

[0053] The information about the correction value A is stored in advance in the storage unit 2c of the optical axis control ECU 2.

[0054] (Optical axis control processing) Next, an example of the optical axis control process of this embodiment will be described with reference to FIGS.

[0055] First, in step S1, the light axis control ECU 2 determines whether or not the vehicle 10 is stopped. This determination can be made, for example, by the control unit 2a of the light axis control ECU 2. In this case, the control unit 2a can determine whether or not the vehicle 10 is stopped based on the output value acquired from the wheel speed sensor 3.

[0056] If it is determined in step S1 that the vehicle 10 is stopped (YES in step S1), the beam axis control ECU 2 determines whether the stopped state of the vehicle 10 is stable (step S2). This determination can also be made, for example, by the control unit 2a. In this case, the control unit 2a determines whether the stopped state of the vehicle 10 is stable based on the output values ​​X and Z acquired from the acceleration sensor 4. Specifically, the control unit 2a can determine whether the stopped state of the vehicle 10 is stable based on whether the output values ​​X and Z acquired from the acceleration sensor 4 are within a predetermined range.

[0057] In step S1, if it is determined that the vehicle 10 is not stopped (NO in step S1), the process ends.

[0058] Returning to step S2, if it is determined in step S2 that the stopped state of the vehicle 10 is stable (YES in step S2), the beam axis control ECU 2 determines whether or not it was determined in the previous step S1 that the vehicle 10 was not stopped (NO in step S1) (step S3). This determination can be made, for example, by the control unit 2a of the beam axis control ECU 2. In order to make this determination, for example, a storage area for storing a previous stop flag (previous stop flag storage area) is provided in the storage unit 2c of the beam axis control ECU 2. Here, when it is determined in step S1 that the vehicle 10 is stopped, the control unit 2a sets the previous stop flag to ON. On the other hand, when it is determined in step S1 that the vehicle 10 is not stopped, the control unit 2a sets the previous stop flag to OFF. In this way, in step S3, the control unit 2a can determine whether or not the previous determination was that the vehicle was traveling by checking the ON / OFF state of the previous stop flag.

[0059] In step S2, if it is determined that the stopped state of the vehicle 10 is stable (NO in step S2), the process is terminated. Note that the reason for terminating the process when the stopped state of the vehicle 10 is not stable is that if the stopped state of the vehicle 10 is not stable, the output value of the acceleration sensor 4 will not be stable, and the tilt angle θ of the vehicle 10 is not accurately determined. v It should be noted that the vehicle control device 1 of the present invention can omit this step.

[0060] In step S3, if the control unit 2a determines that the vehicle 10 is currently moving (YES in step S3), that is, if it determines that the vehicle 10 is stopped for the first time, the calculation unit 2b calculates the tilt angle θ of the vehicle 10. v (= T θ s 3) (step S4). T θ s is stored in the storage unit 2c as the inclination angle of the vehicle 10 that serves as the reference.

[0061] When the process of step S4 is completed, the control unit 2a calculates the inclination angle of the vehicle 10 as a reference. T θ s Based on this, the control angle of the headlamp optical axis P T θ L (Reference control angle: see Figure 3) is determined, and the control angle is T θ L is stored in the storage unit 2c (step S5), and the process ends.

[0062] In step S3, if the control unit 2a determines that the vehicle 10 is not currently moving, that is, if the control unit 2a determines that the vehicle 10 is not currently stopped for the first time (NO in step S3), the calculation unit 2b calculates the tilt angle θ of the vehicle 10 currently stopped. v (=θs) is calculated (step S6).

[0063] Following step S6, the control unit 2a calculates the inclination angle of the vehicle 10 as a reference stored in the memory unit 2c. T θ s and the reference control angle T θ L and the calculated inclination angle θ of the vehicle 10. s Based on this, the control angle θ of the optical axis P of the headlamp L At this time, the control unit 2a calculates the control angle θ using the following equation (1) (step S7). L Calculate. θ L = T θ L +θ s - T θ s ...Equation (1) According to this formula, the inclination angle θ of the vehicle 10 calculated by the calculation unit 2b s is the inclination angle of the reference vehicle 10 T θ s If the angle does not change from θ L = T θ L That is, in step S7, the inclination angle θs of the vehicle 10 calculated by the calculation unit 2b is equal to the inclination angle θs of the vehicle 10 at the initial time. T θ s This is a step for calculating the control angle of the optical axis P when the angle is changed from .

[0064] The control angle of the optical axis P, which is the reference angle in step S5, T θ L and the control angle θ of the optical axis P calculated in step S7. L contains an error due to the deflection of the floor of the vehicle 10. Therefore, the control unit 2a calculates the control angle θ of the optical axis P calculated in step S7. L is corrected by a correction value A that takes into account the deflection of the floor of the vehicle 10 (step S8). At this time, the control unit 2a calculates the corrected control angle as revisedθ L In this case, the corrected control angle of the optical axis is revised θ L Calculate. revisedθ L =θ L ×A...Equation (2) Here, when the acceleration sensor 4 is mounted on the front side of the floor of the vehicle 10, as shown by the dashed line in FIG. 4, the correction value A=1 / α.

[0065] Subsequently, in step S9, the control unit 2a calculates the corrected control angle revised θ of the optical axis P. L The optical axis of the headlamp is controlled based on the above, and the process ends.

[0066] (Action and effect) The above is one embodiment of the vehicle control device 1 of the present invention. Next, the effects achieved by the vehicle control device 1 of this embodiment will be described below.

[0067] The above-described vehicle control device 1 has the following characteristic configuration: Therefore, the vehicle control device 1 can achieve the following unique effects that cannot be achieved by conventional techniques.

[0068] (a) The vehicle control device 1 of the present invention is a vehicle control device 1 having an optical axis control unit (control unit 2a) that controls the optical axis of the headlamps of the vehicle 10 based on an acceleration sensor value output from an acceleration sensor 4 mounted on the vehicle 10, the acceleration sensor 4 being mounted at a location where the acceleration sensor value is affected by deflection due to the load, and the optical axis control unit (control unit 2a) controls the optical axis of the headlamps of the vehicle 10 by taking into account a correction value A that takes into account the deflection due to the load.

[0069] In the vehicle control device 1 of the present invention, the optical axis control unit (control unit 2a) controls the optical axes of the headlamps of the vehicle 10 by taking into account a correction value A that takes into account deflection due to the load. In this way, when the optical axis control unit (control unit 2a) controls the optical axes of the headlamps, the vehicle control device 1 of the present invention can suppress deviations in the optical axis control that occur when the acceleration sensor value is affected by deflection of the vehicle 10. Furthermore, the vehicle control device 1 of the present invention suppresses deviations in the optical axis during optical axis control even when deflection occurs in the vehicle 10 due to the load. Therefore, it is not necessary to change the material of the portion where deflection occurs to a stronger material or change the thickness to suppress the deviation. Therefore, the vehicle control device 1 of the present invention can suppress deviations in the optical axis control that occur due to the load without increasing costs or the weight of the vehicle. Furthermore, the vehicle control device 1 of the present invention is not restricted to a location where deflection due to the load does not occur, thereby improving the degree of freedom in the location where the acceleration sensor 4 is installed.

[0070] (b) The correction value may be set to increase as the pitch angle of the vehicle increases.

[0071] As described above, it is assumed that the relationship between the live load and the pitch angle (inclination angle) of the vehicle 10, and the relationship between the live load and the deflection of the vehicle 10 are both approximately proportional. If this is assumed, the deflection of the vehicle 10 is small when the pitch angle of the vehicle 10 is small, so the correction value A needs to be small. On the other hand, the deflection of the vehicle 10 is large when the pitch angle is large, so the correction value A needs to be large. Therefore, in the vehicle control device 1 of the present invention, the control angle θ of the headlamp optical axis before correction is set to L The corrected control angle of the optical axis is obtained by multiplying the value by a correction value A (for example, 1 / α). L In this way, the control angle θ of the optical axis before correction was calculated. L By setting the correction amount to increase as the value of the correction amount increases, the accuracy of the headlamp optical axis control is further improved.

[0072] In the present invention, even when the pitch angle of the vehicle 10 is small, i.e., when the load is small, the control angle of the light axis is always corrected by the correction value A. In this case, the control angle of the light axis of the headlamp is corrected even when the output value of the acceleration sensor 4 is hardly affected by the deflection of the floor of the vehicle 10, so there are concerns about the effect on the accuracy of the light axis control. However, in the vehicle control device 1 of the present invention, when the pitch angle of the vehicle 10 is small, the correction amount is also set small, so it is thought that there is almost no effect on the accuracy of the light axis control.

[0073] (c) The correction value A may be set in accordance with the mounting position of the acceleration sensor 4.

[0074] The deflection of the vehicle 10 due to the load varies depending on the thickness and material of the floor of the vehicle 10, the mounting structure of the floor, the location of luggage or the like in the vehicle 10, and the position of the seat rail to which the load is applied. Therefore, the influence of the output value Z of the acceleration sensor 4 also varies depending on the mounting position of the acceleration sensor 4. Therefore, in the above-described embodiment, as shown in FIG. 4 , a correction value A (1 / α) when the acceleration sensor 4 is mounted on the front side of the floor of the vehicle 10 and a correction value A (1 / β) when the acceleration sensor 4 is mounted on the rear side of the floor of the vehicle 10 are calculated, and the control angle of the optical axis can be corrected depending on each mounting position. In this way, the vehicle control device 1 of the present invention is configured to set the correction value A depending on the mounting position of the acceleration sensor 4, thereby performing optical axis control using an appropriate correction value A depending on the mounting position of the acceleration sensor 4. Furthermore, this further improves the accuracy of headlamp optical axis control by the vehicle control device of the present invention. Furthermore, since the vehicle 10 is long in the front-to-rear direction, it is considered that the influence of the mounting position of the acceleration sensor 4 on the output value Z of the acceleration sensor 4 is greater in the front-to-rear direction than in the left-to-right direction (vehicle width direction) of the vehicle 10. Therefore, the vehicle control device 1 of the present invention can effectively set the correction value A by setting the correction value A separately depending on whether the acceleration sensor 4 is mounted on the front side or the rear side of the floor.

[0075] (d) The correction value A may be set to a larger value when the acceleration sensor 4 is mounted on the rear side of the vehicle 10 than when the acceleration sensor 4 is mounted on the front side.

[0076] In this way, the vehicle control device 1 of the present invention can perform optical axis control using a more accurate correction value A for a vehicle 10 in which the amount of deflection due to the load is greater on the rear side than on the front side.

[0077] (e) The acceleration sensor 4 may be mounted directly or indirectly on the floor of the vehicle 10 .

[0078] In this way, the vehicle control device 1 of the present invention can control the optical axis of the headlamp by taking into account the correction value A that takes into account the deflection of the floor of the vehicle 10.

[0079] Here, the vehicle control device 1 of the present invention described above is configured to detect the vehicle tilt angle θ v In this configuration, the vehicle tilt angle θ derived by the vehicle tilt angle deriving unit (calculation unit 2b) can be calculated. v There is a concern that the actual pitch angle of the vehicle 10 may include an error caused by the acceleration sensor value being affected by deflection due to the load.

[0080] (f) Based on the above findings, the vehicle control device 1 of the present invention calculates the vehicle tilt angle θ based on the acceleration sensor value output from the acceleration sensor 4. v The vehicle tilt angle deriving unit (calculation unit 2b) is provided to derive the vehicle tilt angle θ v includes an error (|θb-θa|) that occurs when the acceleration sensor value is affected by deflection due to a load relative to the actual pitch angle of the vehicle 10, and the correction value A corrects the error (|θb-θa|) due to the deflection, and the optical axis control unit (control unit 2a) corrects the vehicle tilt angle θ derived by the vehicle tilt angle derivation unit (calculation unit 2b). vand the correction value A, the optical axis of the headlamp of the vehicle 10 may be controlled.

[0081] By adopting the configuration as described above in (f), the vehicle control device 1 of the present invention can accurately detect the vehicle tilt angle θ calculated based on the acceleration sensor value. v The control angle θ derived from L is corrected by the correction value A, and then the headlamp optical axis control is performed. In this way, the vehicle control device 1 of the present invention can correct the vehicle tilt angle θ v This makes it possible to suppress deviations in optical axis control that occur when controlling the optical axis of the headlamp assuming that the actual pitch angle of the vehicle is the actual vehicle pitch angle.

[0082] (g) The vehicle tilt angle derivation unit (calculation unit 2b) calculates the vehicle tilt angle θ under the condition that the vehicle 10 is at a standstill. v The optical axis control unit (control unit 2a) calculates the vehicle tilt angle θ derived by the vehicle tilt angle derivation unit (calculation unit 2b). v and the correction value A, the optical axis of the headlamp may be controlled.

[0083] If the acceleration sensor value changes while the vehicle 10 is traveling, it can be assumed that the change is due to a change in the road surface angle or a change in the acceleration of the vehicle 10. On the other hand, if the acceleration sensor value changes while the vehicle 10 is stopped, it can be assumed that the change is due to a change in the inclination angle of the vehicle 10. Based on this knowledge, the vehicle control device 1 of the present invention calculates the vehicle inclination angle θ on the condition that at least the vehicle 10 is stopped. v As a result, the vehicle control device 1 of the present invention calculates the vehicle tilt angle θ v When a change occurs in the vehicle tilt angle θ v In this way, the vehicle control device 1 of the present invention can perform headlamp optical axis control by detecting the change in the vehicle inclination angle θ when the road surface angle and the acceleration of the vehicle 10 are not changed. v Therefore, the optical axis of the headlamp can be controlled with high accuracy.

[0084] (h) The condition may further include that the vehicle 10 is in a stable stopped state.

[0085] Immediately after the vehicle 10 stops, the acceleration sensor value changes due to vibration of the vehicle 10, etc. Therefore, if the inclination angle of the vehicle 10 is calculated based on the acceleration sensor value, the accuracy of the headlamp optical axis control will decrease. Therefore, the vehicle inclination angle derivation unit (calculation unit) 2b calculates the vehicle inclination angle θ v In this way, the vehicle control device 1 of the present invention can control the optical axes of the headlamps with even greater precision.

[0086] The above are the effects of the vehicle control device 1 according to the embodiment of the present invention, but the vehicle control device 1 of the present invention is not limited to the above embodiment and can be modified in various ways. That is, the above-described vehicle control device 1 merely illustrates one embodiment of the present invention, and the configuration can be appropriately changed, omitted, or added as long as it does not deviate from the spirit of the present invention. That is, the vehicle control device 1 can be one that does not include some or all of the configurations according to (a) to (h) above, one that includes other configurations, or one that realizes the configurations according to (a) to (h) above differently from those exemplified in the above embodiment, within the spirit of the present invention.

[0087] For example, in the above-described embodiment, as shown in FIG. 4, the pitch angle of the vehicle 10 in the loading patterns (i) to (vi) and the tilt angle θ of the vehicle 10 calculated by the calculation unit 2b based on the output value Z of the acceleration sensor 4 are vThe relationship between the load pattern (i) and the load pattern (vi) is plotted, an approximate line is calculated by the least squares method, and the slope is derived. However, the method of deriving the slope to derive the correction value A is not limited to this. For example, the correction value A may be calculated based on the slope of a line passing through two specific plot points among the loading patterns (i) to (vi), such as a line passing through two points between the plot of the loading pattern (i) with the lightest load and the plot of the loading pattern (vi) with the heaviest load. Furthermore, the slope to derive the correction value A may be calculated by the least squares method from some of the plots of the loading patterns (i) to (vi). Even in this case, the vehicle control device 1 of the present invention can control the headlamp beam axis of the vehicle 10 by taking into account the correction value A that takes into account deflection due to the load.

[0088] Furthermore, in the above-described embodiment, the value of the vertical axis (tilt angle θv of the vehicle 10) in Fig. 4 is determined based on the output value Z (actual measurement value) output from the acceleration sensor 4, but, for example, a configuration may be adopted in which the theoretical amount of deflection of the floor of the vehicle 10 in each of the loading patterns (i) to (vi) is calculated and plotted. Even in this case, the vehicle control device 1 of the present invention can control the optical axis of the headlamp of the vehicle 10 by taking into account the correction value A that takes into account the deflection due to the load.

[0089] Furthermore, in the above embodiment, the acceleration sensor 4 is directly or indirectly mounted on the floor of the vehicle 10, but the mounting location of the acceleration sensor 4 is not limited to this. That is, the mounting location of the acceleration sensor 4 on the vehicle 10 can be changed as appropriate as long as the output value Z of the acceleration sensor 4 is affected by deflection caused by the live load. In this case, it is advisable to set the correction value A in advance according to the location.

[0090] The above are embodiments and variations of the vehicle control device 1 according to the present invention, but the present invention is not limited to the above-described embodiments and variations, and it will be easily understood by those skilled in the art that other embodiments are possible within the scope of the claims based on the teachings and spirit of the present invention. [Industrial Applicability]

[0091] The present invention can be suitably used in general vehicle control devices that control the optical axes of vehicle headlamps based on output values ​​from an acceleration sensor mounted on the vehicle. [Explanation of symbols]

[0092] 1: Vehicle control device 2a: Control unit (optical axis control unit) 2b: Arithmetic unit (vehicle oblique angle derivation unit) 4: Acceleration sensor 10: Vehicle

Claims

1. A vehicle control device having a light axis control unit that controls the light axes of headlamps of a vehicle based on an acceleration sensor value output from an acceleration sensor mounted on the vehicle, The acceleration sensor is mounted at a location where the acceleration sensor value is affected by deflection due to a load, The vehicle control device is characterized in that the optical axis control unit controls the optical axis of the headlamp of the vehicle by taking into account a correction value that takes into account deflection due to a load.

2. 2. The vehicle control device according to claim 1, wherein the correction value is set to increase as the pitch angle of the vehicle increases.

3. 3. The vehicle control device according to claim 1, wherein the correction value is set in accordance with a mounting position of the acceleration sensor.

4. a vehicle tilt angle derivation unit that derives a vehicle tilt angle based on the acceleration sensor value output from the acceleration sensor, The vehicle tilt angle includes an error caused by an influence of the acceleration sensor value on an actual pitch angle of the vehicle due to deflection caused by a live load, the correction value corrects the error due to the deflection, 3. The vehicle control device according to claim 1, wherein the optical axis control unit controls the optical axes of the headlamps of the vehicle based on the vehicle inclination angle derived by the vehicle inclination angle derivation unit and the correction value.

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