JP6554212B2 - Control device for vehicle lamp - Google Patents

Description

  The present invention relates to a control device for a vehicle lamp, a vehicle lamp system, and a control method for a vehicle lamp, and more particularly, to a control device for a vehicle lamp used for an automobile etc., a vehicle lamp system, and a control method for a vehicle lamp. It is about.

  2. Description of the Related Art Conventionally, there is known auto-leveling control in which an optical axis position of a vehicular headlamp is automatically adjusted according to a tilt angle in a pitch direction of the vehicle to change an irradiation direction. Generally, in auto-leveling control, a vehicle height sensor is used as a vehicle inclination detection device, and an optical axis position of a headlight is adjusted based on a pitch angle of the vehicle detected by the vehicle height sensor. On the other hand, Patent Document 1 discloses a configuration using a gravity sensor as an inclination detection device. Patent Document 2 discloses a configuration using a three-dimensional gyro sensor that detects an inclination angle with respect to a horizontal plane as an inclination detection device. Patent Document 3 discloses a configuration using an inclinometer that detects an inclination angle with respect to the direction of gravity of a vehicle as an inclination detection device. Further, Patent Document 4 discloses a configuration using an acceleration sensor that detects a gravitational acceleration as a tilt detection device.

  When an acceleration sensor including a gravity sensor or a three-dimensional gyro sensor is used as a vehicle tilt detection device, the auto leveling system can be made cheaper and lighter than when a vehicle height sensor is used. You can also

JP 2000-085459 A JP 2004-314856 A JP 2001-341578 A JP 2009-126268 A

  In the automatic leveling control using the acceleration sensor, the inclination angle detected by the acceleration sensor is the inclination angle of the vehicle with respect to the horizontal plane, including the inclination angle of the road surface with respect to the horizontal plane and the inclination angle of the vehicle with respect to the road surface. On the other hand, the vehicle inclination angle necessary for the automatic leveling control is the vehicle inclination angle with respect to the road surface. Therefore, in the auto leveling control using an acceleration sensor, it is necessary to extract information on the inclination angle of the vehicle with respect to the road surface from the inclination angle of the vehicle with respect to the horizontal plane obtained by the acceleration sensor. On the other hand, the present inventors have come up with a new method for extracting information about the inclination angle of the vehicle with respect to the road surface from the inclination angle of the vehicle with respect to the horizontal plane obtained from the detection value of the acceleration sensor.

  The present invention has been made based on such recognition by the inventors, and the purpose thereof is an inclination angle of the vehicle with respect to the road surface from a detection value of the acceleration sensor in an auto leveling control of a vehicle lamp using the acceleration sensor. It is to provide a new technique for extracting the information.

  In order to solve the above-described problems, an aspect of the present invention is a control device for a vehicular lamp, and the control device detects an acceleration that can be detected by an acceleration sensor and that can derive an acceleration in the vehicle longitudinal direction and the vehicle vertical direction. A vehicle lamp based on a change in a ratio between a time change amount of acceleration in the longitudinal direction of the vehicle and a time change amount of acceleration in the vertical direction of the vehicle in at least one of a reception unit for receiving and acceleration and deceleration of the vehicle And a transmission unit for transmitting the control signal to the optical axis adjustment unit of the vehicle lamp.

  According to this aspect, it is possible to provide a new technique for extracting information on the inclination angle of the vehicle with respect to the road surface from the detection value of the acceleration sensor in the auto-leveling control of the vehicle lamp using the acceleration sensor.

  In the above aspect, the control unit sets the acceleration in the longitudinal direction of the vehicle to the first axis and sets the acceleration in the vertical direction of the vehicle to the second axis, and detects the acceleration sensor at at least one of acceleration and deceleration of the vehicle. The values may be plotted over time, and the straight line or vector slope obtained from at least two points may be used as the ratio.

  In the above aspect, the control unit includes a detection value of the acceleration sensor when the acceleration of the vehicle is within a predetermined range, and a detection value of the acceleration sensor when the deceleration of the vehicle is within the predetermined range. The slope of the straight line or vector obtained from the above may be the ratio.

  In the above aspect, when the inclination angle of the vehicle with respect to the horizontal plane is called a total angle, the total angle includes a first angle that is an inclination angle of the road surface with respect to the horizontal plane and a second angle that is an inclination angle of the vehicle with respect to the road surface. The total angle can be obtained from the detected value of the acceleration sensor, and the control unit holds the reference value of the first angle and the reference value of the second angle, and when the total angle changes while the vehicle is stopped, The control signal is generated using the second angle obtained from the detected value of the acceleration sensor and the reference value of the first angle, the obtained second angle is held as a new reference value, and the total angle changes while the vehicle is traveling In this case, a control signal for instructing to avoid generation of the control signal or maintaining the optical axis position is generated, and the first angle obtained from the detected value of the acceleration sensor and the reference value of the second angle when the vehicle is stopped is newly set. Hold as reference value, ratio If There has changed, it may be corrected optical axis position of the vehicle lamp based on the change in the ratio. According to this aspect, it can be avoided that the detection error of the acceleration sensor is accumulated due to repeated rewriting of the reference values of the first angle and the second angle, and the accuracy of the auto leveling control is reduced, or The reduction in accuracy of the auto leveling control can be reduced.

  In the above aspect, the control unit may derive a difference between the reference value of the second angle and the second angle derived from the ratio, and correct the reference value of the second angle so that the difference becomes small. . The control unit may correct the reference value of the second angle by a correction value smaller than the predetermined threshold when the difference exceeds a predetermined threshold.

  Further, in the above aspect, the control unit acquires and acquires the inclination angle of the vehicle with respect to the road surface from the ratio at the time of acceleration and deceleration of the vehicle in the horizontal plane recorded in advance and the ratio of the current vehicle. The control signal may be generated using the tilt angle of the vehicle with respect to the road surface. According to this aspect, the auto-leveling rewrites the reference value of the road surface angle θr when the total angle θ changes while the vehicle is traveling, and rewrites the reference value of the vehicle posture angle θv when the total angle θ changes while the vehicle is stopped. Optical axis adjustment can be performed without causing an increase in adjustment error caused by repeated rewriting of the reference value, which may occur in the case of control.

  Moreover, in the said aspect, a control part is good also as calculating | requiring a linear approximation formula with respect to the plotted several points, and making the inclination of the said linear approximation formula into a ratio.

  Another aspect of the present invention is a vehicular lamp system, which includes a vehicular lamp that can adjust an optical axis, an acceleration sensor, and a controller for controlling the vehicular lamp. The control unit receives an acceleration that can be detected by an acceleration sensor and is capable of deriving an acceleration in the vehicle front-rear direction and the vehicle vertical direction, and the acceleration in the vehicle front-rear direction at least during acceleration and deceleration of the vehicle is received. The optical axis of the vehicular lamp is adjusted based on a change in the ratio between the time change amount and the time change amount of acceleration in the vehicle vertical direction.

  Still another aspect of the present invention is a control method for a vehicle lamp, and the control method is a control method for a vehicle lamp for adjusting an optical axis of the vehicle lamp using an acceleration sensor, Adjusting the optical axis of the vehicle lamp based on the change in the ratio of the time change of acceleration in the longitudinal direction of the vehicle to the time change of acceleration in the vertical direction of the vehicle during at least one of acceleration and deceleration of the vehicle Features.

  These aspects can also provide a new technique for extracting information about the inclination angle of the vehicle with respect to the road surface from the detection value of the acceleration sensor in the automatic leveling control of the vehicular lamp using the acceleration sensor.

  ADVANTAGE OF THE INVENTION According to this invention, in the automatic leveling control of the vehicle lamp using an acceleration sensor, the new technique which extracts the information about the inclination angle of the vehicle with respect to a road surface from the detection value of an acceleration sensor can be provided.

It is a schematic vertical sectional view explaining the internal structure of the vehicular lamp system according to the first embodiment. It is a functional block diagram explaining operation | movement cooperation with the irradiation control part of a headlamp unit, and the vehicle control part by the side of a vehicle. FIGS. 3A and 3B are schematic diagrams for explaining the relationship between the direction of the motion acceleration vector of the vehicle and the vehicle attitude angle. It is a graph showing the relationship between the vehicle longitudinal acceleration and the vehicle vertical acceleration. 3 is a flowchart of auto leveling control of the vehicular lamp system according to the first embodiment. It is a schematic diagram for demonstrating the auto leveling control of the vehicle lamp system which concerns on Embodiment 3. FIG. 6 is a flowchart of auto leveling control of a vehicle lamp system according to a third embodiment.

  Hereinafter, the present invention will be described based on preferred embodiments with reference to the drawings. The same or equivalent components, members, and processes shown in the drawings are denoted by the same reference numerals, and duplicating descriptions will be omitted as appropriate. In addition, the embodiments do not limit the invention and are merely examples, and all the features and combinations thereof described in the embodiments are not necessarily essential to the invention.

(Embodiment 1)
FIG. 1 is a schematic vertical sectional view for explaining the internal structure of the vehicle lamp system according to the first embodiment. The vehicle lamp system 200 of the present embodiment is a light distribution variable type headlamp system in which a pair of headlamp units formed symmetrically in the left-right direction are disposed one by one on the left and right in the vehicle width direction of the vehicle. The headlight units disposed on the left and right sides have substantially the same configuration except that they have a symmetrical structure, so in the following, the structure of the headlight unit 210R on the right side will be described. The description of the unit is omitted as appropriate. In the case of describing each member of the left headlight unit, for convenience of explanation, each member is assigned the same reference numeral as the corresponding member of the headlight unit 210R.

  The headlamp unit 210R includes a lamp body 212 having an opening on the front side of the vehicle, and a translucent cover 214 that covers the opening. The lamp body 212 has a detachable cover 212a on the rear side of the vehicle, which can be removed when the bulb 14 is replaced or the like. A lamp chamber 216 is formed by the lamp body 212 and the translucent cover 214. In the lamp chamber 216, a lamp unit 10 (vehicle lamp) for emitting light to the front of the vehicle is accommodated.

  In a part of the lamp unit 10, a lamp bracket 218 having a pivot mechanism 218a which is the swing center of the lamp unit 10 in the vertical and horizontal directions is formed. The lamp bracket 218 is screwed with an aiming adjustment screw 220 that is rotatably supported on the wall surface of the lamp body 212. Therefore, the lamp unit 10 is fixed at a predetermined position in the lamp chamber 216 determined in the adjusted state of the aiming adjustment screw 220, and is inclined forward or backward about the pivot mechanism 218a based on that position. The posture can be changed. Further, on the lower surface of the lamp unit 10, a rotation shaft 222a of a swivel actuator 222 for constituting a light distribution variable headlamp for curvilinear road which illuminates the traveling direction when traveling on a curvilinear road or the like is fixed. The swivel actuator 222 is fixed to the unit bracket 224.

  The unit bracket 224 is connected to a leveling actuator 226 disposed outside the lamp body 212. The leveling actuator 226 is configured of, for example, a motor that extends and retracts the rod 226 a in the directions of arrows M and N. When the rod 226a extends in the direction of the arrow M, the lamp unit 10 swings so as to be inclined rearward about the pivot mechanism 218a. Conversely, when the rod 226a is shortened in the direction of the arrow N, the lamp unit 10 pivots so as to be in a forwardly inclined posture about the pivot mechanism 218a. When the lamp unit 10 is in the backward tilt position, it is possible to perform leveling adjustment in which the pitch angle of the optical axis O, that is, the angle in the vertical direction of the optical axis O is directed upward. Further, when the lamp unit 10 is tilted forward, leveling adjustment can be performed to turn the pitch angle of the optical axis O downward.

  The illumination control unit 228 (control unit, control unit that executes on / off control of the lamp unit 10, formation control of the light distribution pattern, adjustment of the light axis of the lamp unit 10, etc. on the inner wall surface of the lamp chamber 216 below the lamp unit 10. ) Are arranged. In the case of FIG. 1, an irradiation control unit 228R for controlling the headlamp unit 210R is arranged. The irradiation control unit 228R also executes control of the swivel actuator 222, the leveling actuator 226, and the like. The irradiation control unit 228R may be provided outside the headlamp unit 210R.

  The lamp unit 10 can include an aiming adjustment mechanism. For example, an aiming pivot mechanism (not shown) serving as a swing center at the time of aiming adjustment is disposed at a connecting portion between the rod 226a of the leveling actuator 226 and the unit bracket 224. Further, the above-described aiming adjustment screw 220 is disposed on the lamp bracket 218 at an interval in the vehicle width direction. Then, by rotating the two aiming adjustment screws 220, the lamp unit 10 can be pivoted vertically and horizontally around the aiming pivot mechanism, and the optical axis O can be adjusted vertically and horizontally. This aiming adjustment is performed, for example, at the time of vehicle shipment, vehicle inspection, or replacement of the headlamp unit 210R. Then, the headlight unit 210R is adjusted to a posture determined in design, and based on this posture, formation control of a light distribution pattern and adjustment control of the optical axis position are performed.

  The lamp unit 10 includes a shade mechanism 18 including a rotary shade 12, a bulb 14 as a light source, a lamp housing 17 for supporting the reflector 16 on the inner wall, and a projection lens 20. As the bulb 14, for example, an incandescent bulb, a halogen lamp, a discharge bulb, an LED, or the like can be used. In the present embodiment, an example in which the bulb 14 is configured by a halogen lamp is shown. The reflector 16 reflects the light emitted from the bulb 14. A part of the light from the bulb 14 and the light reflected by the reflector 16 is guided to the projection lens 20 through the rotary shade 12. The rotary shade 12 is a cylindrical member rotatable about a rotation axis 12a, and includes a cutout portion partially cut away in the axial direction and a plurality of shade plates (not shown). Either the notch or the shade plate is moved onto the optical axis O to form a predetermined light distribution pattern. At least a part of the reflector 16 has an elliptical spherical shape, and the elliptical spherical surface is set so that the cross-sectional shape including the optical axis O of the lamp unit 10 is at least a part of the elliptical shape. The elliptical spherical portion of the reflector 16 has a first focal point substantially at the center of the bulb 14 and a second focal point on the rear focal plane of the projection lens 20.

  The projection lens 20 is disposed on an optical axis O extending in the longitudinal direction of the vehicle. The bulb 14 is disposed rearward of the rear focal plane, which is a focal plane including the rear focal point of the projection lens 20. The projection lens 20 is a plano-convex aspheric lens having a convex front side surface and a flat rear side surface, and a light source image formed on the rear focal plane as a reverse image, a virtual vertical screen in front of the vehicle lamp system 200 Project above. The configuration of the lamp unit 10 is not particularly limited to this, and may be a reflective lamp unit without the projection lens 20.

  FIG. 2 is a functional block diagram for explaining the operation cooperation between the irradiation control unit of the headlight unit configured as described above and the vehicle control unit on the vehicle side. As described above, the configuration of the right headlight unit 210R and the left headlight unit 210L is basically the same, so only the headlamp unit 210R side will be described and the headlight unit 210L side will be described. Description is omitted.

  The irradiation control unit 228R of the headlamp unit 210R includes a receiving unit 228R1, a control unit 228R2, a transmitting unit 228R3, and a memory 228R4. The irradiation control unit 228R controls the power supply circuit 230 based on the information obtained from the vehicle control unit 302 mounted on the vehicle 300, and executes the lighting control of the valve 14. Further, the irradiation control unit 228R controls the variable shade control unit 232, the swivel control unit 234, and the leveling control unit 236 (optical axis adjustment unit) based on the information obtained from the vehicle control unit 302. Various information transmitted from the vehicle control unit 302 is received by the receiving unit 228R1, and various control signals are generated by the control unit 228R2 from the information and information stored in the memory 228R4 as necessary. Then, the control signal is transmitted to the power supply circuit 230 of the lamp unit 10, the variable shade control unit 232, the swivel control unit 234, the leveling control unit 236, and the like by the transmission unit 228R3. The memory 228R4 is, for example, a nonvolatile memory.

  The variable shade control unit 232 rotationally controls the motor 238 connected to the rotation shaft 12 a of the rotary shade 12 to move a desired shade plate or a notch on the optical axis O. The swivel controller 234 also controls the swivel actuator 222 to adjust the angle of the optical axis O of the lamp unit 10 in the vehicle width direction (left-right direction). For example, the optical axis O of the lamp unit 10 is directed in the direction of traveling from now on during turning such as traveling on a curved road or turning left and right. The leveling control unit 236 controls the leveling actuator 226 to adjust the optical axis O of the lamp unit 10 in the vehicle vertical direction (pitch angle direction). For example, the reach of the front irradiation light is adjusted to the optimum distance by adjusting the posture of the lamp unit 10 according to the forward and backward inclination of the vehicle posture when the load amount is increased or decreased or the number of passengers is increased or decreased. The vehicle control unit 302 provides similar information to the headlamp unit 210L, and the irradiation control unit 228L (control unit, control device) provided in the headlamp unit 210L is the same as the irradiation control unit 228R. Execute the control.

  The light distribution pattern formed by the headlight units 210L and 210R can be switched according to the operation content of the light switch 304 by the driver. In this case, according to the operation of the light switch 304, the irradiation controllers 228L and 228R control the motor 238 via the variable shade controller 232 to determine the light distribution pattern formed by the lamp unit 10. In addition, the headlamp units 210L and 210R are automatically controlled so as to form an optimal light distribution pattern by detecting various states of the vehicle 300 and the surroundings of the vehicle with various sensors regardless of the operation of the light switch 304. Also good. The automatic formation control of the light distribution pattern is executed, for example, when the automatic formation control of the light distribution pattern is instructed by the light switch 304.

  A camera 306 such as a stereo camera is connected to the vehicle control unit 302 in order to detect an object such as a preceding vehicle or an oncoming vehicle. Image frame data captured by the camera 306 is subjected to predetermined image processing such as object recognition processing in the image processing unit 308, and the recognition result is provided to the vehicle control unit 302. In addition, the vehicle control unit 302 can also acquire information from the steering sensor 310, the vehicle speed sensor 312, the navigation system 314, the acceleration sensor 316, and the like mounted on the vehicle 300. Thus, the irradiation control units 228L and 228R can select a light distribution pattern to be formed according to the traveling state or posture of the vehicle 300, or change the direction of the optical axis O.

  Next, auto leveling control by the vehicular lamp system 200 having the above-described configuration will be described in detail. FIGS. 3A and 3B are schematic diagrams for explaining the relationship between the direction of the motion acceleration vector of the vehicle and the vehicle attitude angle. FIG. 3A shows a state in which a vehicle attitude angle θv, which will be described later, is not changed, and FIG. 3B shows a state in which the vehicle attitude angle θv is changed. 3A and 3B, the motion acceleration vector α and the resultant acceleration vector β generated when the vehicle 300 moves forward are shown by solid arrows, and the motion acceleration generated when the vehicle 300 decelerates or reverses. The vector α and the resultant acceleration vector β are indicated by dashed arrows. FIG. 4 is a graph showing the relationship between the vehicle longitudinal acceleration and the vehicle vertical acceleration.

  For example, when the luggage is placed in the luggage compartment at the rear of the vehicle or the occupant is in the rear seat, the vehicle posture is in the backward inclination posture, and when the baggage is lowered or the occupant in the rear seat gets off, the vehicle posture is the backward inclination posture Lean forward. The irradiation direction of the lamp unit 10 also fluctuates up and down corresponding to the posture state of the vehicle 300, and the front irradiation distance becomes longer or shorter. Therefore, the irradiation control units 228L and 228R receive the detection value of the acceleration sensor 316 via the vehicle control unit 302, and control the leveling actuator 226 via the leveling control unit 236 to set the pitch angle of the optical axis O to the vehicle The angle corresponds to the posture. As described above, by performing auto-leveling control that performs the leveling adjustment of the lamp unit 10 in real time based on the vehicle attitude, the reaching distance of the forward irradiation is optimally adjusted even if the vehicle attitude changes according to the use situation of the vehicle 300 can do.

  The acceleration sensor 316 is, for example, a triaxial acceleration sensor having an X axis, a Y axis, and a Z axis that are orthogonal to each other. The acceleration sensor 316 is attached to the vehicle 300 such that the X axis of the sensor is along the longitudinal axis of the vehicle 300, the Y axis of the sensor is along the left and right axis of the vehicle 300, and the Z axis of the sensor is along the vertical axis of the vehicle 300. . The acceleration sensor 316 detects the inclination of the vehicle 300 with respect to the gravitational acceleration vector G, and outputs a numerical value of each axis component of the gravitational acceleration vector G in the three-axis directions. In other words, acceleration sensor 316 includes a road surface angle θr, which is the inclination angle (first angle) of the road surface with respect to the horizontal plane, and a vehicle attitude angle θv, which is the vehicle inclination angle (second angle) with respect to the road surface. The total angle θ, which is the angle of inclination of the (total angle), can be detected as a vector. Further, the acceleration sensor 316 detects a combined acceleration vector β obtained by combining the gravitational acceleration vector G and the motion acceleration vector α generated by the movement of the vehicle 300 when the vehicle 300 travels. Output the numerical value of each axis component. The road surface angle θr, the vehicle attitude angle θv, and the total angle θ are respectively an angle in the vertical direction of the X axis, in other words, an angle in the pitch direction of the vehicle 300. Further, in the following description, the component of the acceleration sensor 316 in the Y-axis direction, that is, the angle in the roll direction of the vehicle 300 is not considered. Note that the acceleration sensor 316 may be attached to the vehicle 300 in an arbitrary posture. In this case, the numerical values of the X-axis, Y-axis, and Z-axis components output from the acceleration sensor 316 are converted by the irradiation control unit 228R into components of the vehicle front-rear axis, left-right axis, and vertical axis.

  The auto-leveling control is intended to absorb the change in the front irradiation distance of the vehicular lamp along with the change in the inclination angle of the vehicle in the pitch direction and to keep the front reach distance of the irradiation light optimal. Therefore, the vehicle inclination angle required for the automatic leveling control is the vehicle attitude angle θv. That is, it is desirable to adjust the optical axis position of the lamp unit 10 when the vehicle attitude angle θv changes, and to maintain the optical axis position of the lamp unit 10 when the road surface angle θr changes. In order to realize this, it is necessary to extract information about the vehicle attitude angle θv from the total angle θ obtained from the acceleration sensor 316.

  Here, the vehicle 300 moves in parallel to the road surface. Therefore, the motion acceleration vector α is a vector parallel to the road surface regardless of the vehicle attitude angle θv. Further, as shown in FIG. 3A, when the vehicle attitude angle θv of the vehicle 300 is 0 °, theoretically, the X axis of the acceleration sensor 316 (or the longitudinal axis of the vehicle 300) is parallel to the road surface Therefore, the motion acceleration vector α is a vector parallel to the X axis of the acceleration sensor 316. Therefore, the locus of the tip of the combined acceleration vector β detected by the acceleration sensor 316 when the magnitude of the motion acceleration vector α changes due to acceleration / deceleration of the vehicle is a straight line parallel to the X axis. On the other hand, as shown in FIG. 3B, when the vehicle posture angle θv is not 0 °, the X axis of the acceleration sensor 316 is diagonally shifted with respect to the road surface, so the motion acceleration vector α is the X axis of the acceleration sensor 316. It becomes a vector extending diagonally with respect to. Therefore, the locus of the tip of the resultant acceleration vector β when the magnitude of the motion acceleration vector α changes due to acceleration and deceleration of the vehicle is a straight line inclined with respect to the X axis.

Therefore, the irradiation control unit 228R receives the acceleration in the vehicle longitudinal direction and the vehicle vertical direction from the acceleration sensor 316 by the receiving unit 228R1. Then, the control unit 228R2 calculates a ratio between the time change amount of the acceleration in the vehicle longitudinal direction and the time change amount of the acceleration in the vehicle vertical direction at least when the vehicle 300 is accelerated and decelerated. For example, as shown in FIG. 4, the irradiation control unit 228R sets the vehicle longitudinal acceleration at the first axis (x axis) and the vehicle vertical acceleration at the second axis (z axis). The detected values of the acceleration sensor 316 at least one of acceleration and deceleration are plotted over time. Points t _{A1 to} t _An are detected values of the acceleration sensor 316 at times t _{1 to} t _n in the state shown in FIG. Points t _{B1 to} t _Bn are detection values of the acceleration sensor 316 at times t _{1 to} t _n in the state shown in FIG. Then, the inclination of a straight line or a vector obtained from at least two points is calculated as the above-described ratio. In the present embodiment, the irradiation controller 228R obtains the linear approximation formulas A and B using the least square method or the like for the plotted plural points t _{A1 to} t _An and t _{B1 to} t _Bn , and the linear approximation formula The slope of A and B is calculated as a ratio.

  When the vehicle attitude angle θv is 0 °, a linear approximation formula A parallel to the x axis is obtained from the detection value of the acceleration sensor 316. That is, the slope of the linear approximation formula A is zero. On the other hand, when the vehicle attitude angle θv is not 0 °, a linear approximation formula B having an inclination according to the vehicle attitude angle θv is obtained from the detection value of the acceleration sensor 316. Therefore, by measuring the change in the ratio of the time change amount of acceleration in the longitudinal direction of the vehicle and the vertical direction of the vehicle at the time of acceleration / deceleration of the vehicle 300, the vehicle attitude as information on the vehicle attitude angle θv from the detection value of the acceleration sensor 316 The change of the angle θv can be known. Then, by using the obtained change information of the vehicle attitude angle θv, it is possible to realize more accurate auto leveling control.

  The vehicle lamp system 200 according to the present embodiment performs the following auto-leveling control using information on the vehicle attitude angle θv obtained by detecting the change in the ratio described above. That is, first, the vehicle 300 is placed on a horizontal plane and brought into a reference state, for example, at a manufacturing factory of a vehicle manufacturer or a maintenance shop of a dealer. In the reference state, a state where one person is in the driver's seat of the vehicle 300 or an empty state is set. Then, the irradiation control unit 228R is initialized by a switch operation of the factory initialization processing device or communication of a CAN (Controller Area Network) system that connects the irradiation control unit 228R and the acceleration sensor 316 via the vehicle control unit 302. Is transmitted. The initialization signal transmitted to the irradiation controller 228R is received by the receiver 228R1 and sent to the controller 228R2. When the control unit 228R2 receives the initialization signal, the control unit 228R2 performs initial aiming adjustment using the output value of the acceleration sensor 316 received by the receiving unit 228R1 as a reference tilt angle. Further, the control unit 228R2 records the output value of the acceleration sensor 316 at this time in the memory 228R4 as the reference value (θr = 0 °) of the road surface angle θr and the reference value (θv = 0 °) of the vehicle attitude angle θv. Hold these reference values.

  While the vehicle is traveling, it is rare that the load amount and the number of passengers increase and decrease to change the vehicle attitude angle θv. Therefore, the change of the total angle θ during traveling can be estimated as the change of the road surface angle θr. Therefore, the control unit 228R2 avoids generation of a control signal instructing optical axis adjustment when the total angle θ changes during vehicle travel. Note that the control unit 228R2 may generate a control signal instructing to maintain the optical axis position in response to a change in the total angle θ during vehicle travel, and transmit the control signal from the transmission unit 228R3 to the leveling control unit 236. Whether the vehicle 300 is traveling can be determined from the vehicle speed obtained from the vehicle speed sensor 312, for example. The “during vehicle traveling” is a period, for example, from when the detection value of the vehicle speed sensor 312 exceeds zero until the detection value of the vehicle speed sensor 312 becomes zero. This “during vehicle travel” can be set as appropriate based on experiments and simulations by the designer.

  Then, when the vehicle is stopped, the control unit 228R2 subtracts the reference value of the vehicle attitude angle θv read from the memory 228R4 from the current total angle θ detected by the acceleration sensor 316 to calculate the road surface angle θr at the time of the vehicle stop. To do. The road surface angle θr is recorded in the memory 228R4 as a new reference value of the road surface angle θr. The “when the vehicle is stopped” is, for example, when the detection value of the acceleration sensor 316 is stabilized after the detection value of the vehicle speed sensor 312 becomes zero. When the detection value of the acceleration sensor 316 is stabilized, it takes some time from the stop of the vehicle 300 to the stabilization of the vehicle posture, and in the state where the vehicle posture is not stable, the total angle θ accurate Is difficult to detect. This “at the time of stability” may be when the amount of change of the detection value of the acceleration sensor 316 per unit time becomes equal to or less than a predetermined amount, or after a predetermined time has elapsed since the detection value of the vehicle speed sensor 312 becomes zero. It is good. The “when the vehicle is stopped”, “predetermined amount”, and “predetermined time” can be appropriately set based on experiments and simulations by the designer.

  On the other hand, since it is rare that the vehicle 300 moves and the road surface angle θr changes while the vehicle is stopped, the change in the total angle θ while the vehicle is stopped can be estimated as the change in the vehicle attitude angle θv. Therefore, when the total angle θ changes while the vehicle is stopped, the control unit 228R2 uses the vehicle attitude angle θv obtained from the detection value of the acceleration sensor 316 and the reference value of the road surface angle θr read from the memory 228R4 to Generate control signals that indicate axis adjustment. Specifically, the control unit 228R2 repeatedly calculates the vehicle attitude angle θv at a predetermined timing while the vehicle is stopped. The vehicle attitude angle θv is obtained by subtracting the reference value of the road surface angle θr recorded in the memory 228R4 from the current total angle θ received from the acceleration sensor 316. Then, when the difference between the calculated vehicle attitude angle θv and the reference value of the vehicle attitude angle θv held in memory 228R4 is equal to or larger than a predetermined amount, control unit 228R2 newly obtains the vehicle attitude angle. A control signal is generated based on θv. As a result, frequent optical axis adjustment can be avoided. As a result, the control burden on the control unit 228R2 can be reduced, and the life of the leveling actuator 226 can be extended. The generated control signal is transmitted to the leveling control unit 236 by the transmission unit 228R3, and optical axis adjustment based on the control signal is executed. The calculated vehicle attitude angle θv is recorded in the memory 228R4 as a new reference value.

  The “stopping vehicle” is, for example, from when the detection value of the acceleration sensor 316 is stabilized to when the vehicle starts, and this “when starting the vehicle” is, for example, when the detection value of the vehicle speed sensor 312 exceeds zero. . The “stopping vehicle” can be set as appropriate based on experiments and simulations by the designer.

  The control unit 228R2 records the output value of the acceleration sensor 316 at least one of acceleration and deceleration of the vehicle, for example, a predetermined time when the vehicle starts or stops. The control unit 228R2 plots the recorded output value on the coordinates with the acceleration in the vertical direction of the vehicle as the first axis and the acceleration in the vertical direction of the vehicle as the second axis, and the linear approximation formula is continuously or predetermined by the least squares method. Calculate every hour. Then, the control unit 228R2 generates a control signal instructing adjustment of the optical axis of the lamp unit 10 based on the change in the slope of the obtained linear approximation formula, thereby correcting the optical axis position. In addition, the reference value of the vehicle attitude angle θv held in the memory 228R4 is corrected. For example, the control unit 228R2 compares the inclination of the obtained linear approximation expression with the inclination of the linear approximation expression obtained in the previous calculation, and when a change in the inclination of the linear approximation expression is detected, the change of the inclination The correction process is executed based on the above.

  Further, for example, it is assumed that the vehicle attitude angle θv held in the memory 228R4 is p °, and the integrated value from the initial calculation of the change in the slope of the linear approximation formula is q °. Alternatively, the amount of change in the vehicle attitude angle θv during the previous stop of the vehicle, that is, the difference between the vehicle attitude angle θv held at the time of the vehicle stop and the vehicle attitude angle θv held at the vehicle start is p ° It is assumed that the difference in slope between the linear approximation formula calculated at the start of the vehicle and the linear approximation formula calculated at the start of this time is q °. In this case, the control unit 228R2 generates a control signal for adjusting the optical axis position by an error (pq) of the vehicle attitude angle θv, and the transmission unit 228R3 transmits the control signal. Further, the control unit 228R2 corrects the reference value of the vehicle attitude angle θv held in the memory 228R4 by (p−q) °. Thereby, as described above, it is possible to prevent the accuracy of the auto-leveling control from being lowered due to the accumulation of detection errors of the acceleration sensor 316 by repeatedly rewriting the reference values of the road surface angle θr and the vehicle attitude angle θv. it can. Alternatively, it is possible to reduce the decrease in accuracy of the auto leveling control.

  Alternatively, the reference value correction method for the optical axis position and the vehicle attitude angle θv may be as follows. That is, when disturbances such as the inclination of the vehicle attitude caused by acceleration and deceleration of the vehicle 300 and the inclination of the vehicle attitude caused by the curving of the vehicle 300 can not be excluded, the amount of change of the inclination of the linear approximation formula is the vehicle attitude angle θv There is a possibility of a large deviation from the amount of change. In this case, even if the optical axis position and the reference value of the vehicle attitude angle θv are corrected by the change amount of inclination of the linear approximation formula, the deviation from the actual vehicle attitude angle θv occurs. In addition, since the inclination of the linear approximation equation is changing, there is a high possibility that the actual vehicle attitude angle θv is deviated from the held reference value, so the optical axis adjustment using the held reference value is performed. There is a possibility that auto leveling control cannot be performed with high accuracy even if is implemented. Therefore, when a change in inclination of the ratio or the linear approximation formula is detected, the control unit 228R2 brings the optical axis position closer to the horizontal direction or the initial position as correction control of the optical axis position based on the change in the inclination. The reference value of the vehicle attitude angle θv is corrected so as to approach 0 °. As a result, even when the light axis position of the lamp unit 10 can not accurately follow the change in the vehicle attitude angle θv, the light axis position is brought close to the horizontal or initial position to ensure driver's visibility. Safe functions can be realized.

  The control unit 228R2 calculates the calculated vehicle attitude angle θv when the difference between the calculated vehicle attitude angle θv and the reference value of the vehicle attitude angle θv held in the memory 228R4 is equal to or greater than a predetermined amount. May be recorded in the memory 228R4 as a new reference value. Similarly, when the difference between the calculated road surface angle θr and the reference value of the road surface angle θr recorded in the memory 228R4 is equal to or larger than a predetermined amount, the control unit 228R2 newly updates the calculated road surface angle θr. It may be recorded in the memory 228R4 as a standard value. Thus, frequent rewriting of the reference value of the road surface angle θr or the vehicle attitude angle θv can be avoided. In addition, the control unit 228R2 may calculate the road surface angle θr when the total angle θ at the start of the vehicle 300 is different from the total angle θ at the stop. Thereby, the control load on the control unit 228R2 can be reduced.

  Further, the control unit 228R2 records the detection value of the acceleration sensor 316 at the time of acceleration / deceleration between one start and stop of the vehicle 300, calculates a linear approximation formula at the time of vehicle stop, etc. The correction process may be executed.

  FIG. 5 is a flowchart of the auto leveling control of the vehicle lamp system according to the first embodiment. In the flowchart of FIG. 5, the processing procedure of each part is displayed by a combination of S (initial letter of Step) meaning a step and a number. In addition, if a determination process is executed by a process displayed by a combination of S and a number, and the determination result is affirmative, Y (acronym for Yes) is added, for example (Y in S101). On the contrary, if the determination result is negative, N (acronym for No) is added and, for example, (N in S101) is displayed. This flow is repeatedly performed at a predetermined timing by the irradiation control unit 228R (control unit 228R2) when the ignition is turned on, for example, in a state where the execution of the auto leveling control mode is instructed by the light switch 304, Exit when is turned off.

  First, the control unit 228R2 determines whether the vehicle is traveling (S101). When the vehicle is traveling (Y in S101), the control unit 228R2 determines whether the vehicle is accelerating or decelerating (S102). The acceleration / deceleration of the vehicle can be detected from the detection value of the acceleration sensor 316, the presence or absence of depression of the accelerator pedal and the brake pedal (both not shown), and the like. When the vehicle is accelerating or decelerating (Y in S102), the control unit 228R2 calculates a linear approximation formula from the plurality of output values of the acceleration sensor 316, and the inclination of the obtained linear approximation formula and the previously calculated linear approximation formula And the slope of (S103). Then, the control unit 228R2 determines whether a change in the slope of the linear approximation formula has been detected (S104). When a change in inclination of the linear approximation formula is detected (Y in S104), the control unit 228R2 generates a control signal instructing optical axis adjustment, corrects the optical axis position, and determines the reference value of the vehicle attitude angle θv. It corrects (S105). Thereafter, the control unit 228R2 avoids the optical axis adjustment without generating the control signal instructing the optical axis adjustment even if the total angle θ detected by the acceleration sensor 316 changes (S106), and executes this routine. finish. The control unit 228R2 also avoids optical axis adjustment (S106) when the vehicle is not accelerating or decelerating (N in S102) and when a change in inclination of the linear approximation formula is not detected (N in S104), This routine ends.

  When the vehicle is not traveling (N in S101), the control unit 228R2 determines whether the vehicle is at a stop (S107). When the vehicle is stopped (Y in S107), the control unit 228R2 subtracts the reference value of the vehicle posture angle θv from the current total angle θ to calculate the road surface angle θr (S108), and calculates the calculated road surface angle θr The new reference value is recorded in the memory 228R4 (S109). Then, the irradiation control unit 228R avoids the optical axis adjustment (S106) and ends this routine.

  When the vehicle is not stopped (N in S107), this means that the vehicle is stopped, so the control unit 228R2 subtracts the reference value of the road surface angle θr from the current total angle θ to obtain the vehicle attitude angle θv. Calculate (S110). Subsequently, the control unit 228R2 determines whether the difference between the calculated vehicle attitude angle θv and the reference value of the vehicle attitude angle θv is equal to or greater than a predetermined amount (S111). When the difference is less than the predetermined amount (N in S111), the control unit 228R2 avoids the optical axis adjustment (S106) and ends this routine. If the difference is equal to or larger than the predetermined amount (Y in S111), the control unit 228R2 adjusts the optical axis position based on the calculated vehicle attitude angle θv (S112). Then, the control unit 228R2 records the calculated vehicle attitude angle θv as a reference value in the memory 228R4 (S113), and ends this routine.

  For the left headlamp unit 210L, the irradiation control unit 228L (control unit 228L2) performs the same control. Alternatively, one of the irradiation control units 228L and 228R calculates the vehicle attitude angle θv and the road surface angle θr, and the other adjusts the optical axis O by acquiring the calculated vehicle attitude angle θv and the road surface angle θr. Also good.

  In addition, while the vehicle is traveling, it is generally estimated that the time during which the vehicle 300 maintains a constant speed is short, and that most of the time is accelerating / decelerating. Therefore, step 102 for determining whether the vehicle 300 is accelerating or decelerating may be omitted.

  As described above, the vehicle lamp system 200 according to the present embodiment receives the acceleration that can be derived from the acceleration in the vehicle longitudinal direction and the vehicle vertical direction, detected by the acceleration sensor 316, and at the time of acceleration of the vehicle 300 The optical axis of the lamp unit 10 is adjusted based on the change in the ratio of the time change amount of the acceleration in the longitudinal direction of the vehicle to the time change amount of the acceleration in the vertical direction of the vehicle in at least one of deceleration. As described above, the vehicle lamp system 200 according to the present embodiment is based on the change in the ratio of the time change amount of acceleration in the vehicle longitudinal direction to the time change amount of acceleration in the vehicle vertical direction during vehicle acceleration / deceleration. The information about the vehicle attitude angle θv is acquired using a new extraction method of acquiring the change of the vehicle. That is, the vehicle lamp system 200 acquires information about the vehicle attitude angle θv from the plot characteristics of the acceleration sensor 316. Therefore, the vehicle lamp system 200 according to the present embodiment can provide a new technique for extracting information about the vehicle posture angle θv from the total angle θ detected by the acceleration sensor 316.

  Further, when the total angle θ changes while the vehicle is traveling, the vehicle lamp system 200 according to the present embodiment derives the road surface angle θr from the changed total angle θ and the reference value of the vehicle attitude angle θv. When the total angle θ changes while the vehicle is stopped, the vehicle attitude angle θv is derived from the changed total angle θ and the reference value of the road surface angle θr, and held. The reference value of the vehicle attitude angle θv is rewritten. The vehicle lamp system 200 corrects the optical axis position of the lamp unit 10 by using information on the vehicle attitude angle θv extracted by the above-described method when the vehicle 300 is accelerated or decelerated. Therefore, auto leveling control using an acceleration sensor can be performed with higher accuracy.

Second Embodiment
The vehicle lamp system 200 according to the second embodiment derives the vehicle attitude angle θv from the ratio of the time change amount of acceleration in the vehicle longitudinal direction to the time change amount of acceleration in the vehicle vertical direction, and the obtained vehicle attitude angle θv Is used to adjust the optical axis. Hereinafter, the present embodiment will be described. In addition, since the main configuration of the vehicle lamp system 200 is the same as that of the first embodiment, the same configuration as that of the first embodiment is denoted by the same reference numeral, and the description and illustration thereof will be omitted as appropriate.

  The vehicle lamp system 200 according to the present embodiment performs the following auto-leveling control using information on the vehicle attitude angle θv obtained by detecting the change in the ratio described above. That is, first, for example, in a manufacturing plant of a vehicle maker or a maintenance shop of a dealer, the vehicle 300 is set to a reference state in which it travels on a horizontal surface, and the vehicle 300 is accelerated or decelerated in that state. Then, the control unit 228R2 receives the acceleration from the acceleration sensor 316 as the initialization processing, and at least one of the acceleration time and the deceleration time of the vehicle 300, the time variation of the acceleration in the longitudinal direction of the vehicle and the time of the acceleration in the vertical direction Calculate the ratio to the amount of change. The control unit 228R2 records the obtained ratio as a reference value in the memory 228R4.

  In a situation where the vehicle 300 is actually used, the control unit 228R2 determines the amount of time change in acceleration in the vehicle longitudinal direction and acceleration in the vehicle vertical direction in the current vehicle at least during acceleration and deceleration of the vehicle 300. The ratio with the time change amount is calculated. Then, the control unit 228R2 acquires the vehicle attitude angle θv from the reference value of the ratio recorded in advance by the initialization process and the ratio of the current vehicle, and performs the optical axis adjustment using the acquired vehicle attitude angle θv .

For example, in the initialization processing, the control unit 228R2 plots detection values of the acceleration sensor 316 on a coordinate with the acceleration in the vertical direction of the vehicle as a first axis and the acceleration in the vertical direction of the vehicle as a second axis. The reference linear approximation formula is obtained from the equation (4), and the inclination of the reference linear approximation formula is calculated as the reference value of the ratio. In addition, in an actual usage condition of the vehicle, the control unit 228R2 records the output value of the acceleration sensor 316, for example, for a predetermined time when the vehicle starts or stops, and plots the recorded output value on coordinates. A linear approximation formula is obtained, and the inclination of the linear approximation formula is calculated as a ratio. Here, an angle (θ _AB in FIG. 4) formed by the reference linear approximation formula and the linear approximation formula calculated under the actual usage condition corresponds to the vehicle attitude angle θv. Therefore, the vehicle attitude angle θv can be obtained by comparing the inclinations of the two linear approximations or the ratio described above.

  As described above, in the vehicular lamp system 200 according to the present embodiment, the vehicle attitude angle θv is obtained from the ratio when the vehicle 300 is on a horizontal plane and the ratio of the current vehicle to adjust the optical axis. We are carrying out. Therefore, in the case of auto-leveling control, the reference value of the road surface angle θr is rewritten when the total angle θ changes while the vehicle is traveling, and the reference value of the vehicle attitude angle θv is rewritten when the total angle θ changes while the vehicle is stopped. May cause an increase in adjustment error due to repeated rewriting of the reference value, but in the case of the automatic leveling control of the present embodiment, the optical axis position is adjusted without incurring such an increase in adjustment error. Can do.

(Embodiment 3)
The vehicular lamp system 200 according to the third embodiment calculates a linear approximation equation using a set of sensor output values during vehicle acceleration and sensor output values during vehicle deceleration as a set. It is. Hereinafter, the present embodiment will be described. In addition, since the main structure of the vehicle lamp system 200 is the same as that of Embodiment 1, the same code | symbol is attached | subjected about the structure similar to Embodiment 1, and the description and illustration are abbreviate | omitted suitably.

  FIG. 6 is a schematic view for explaining auto-leveling control of the vehicle lamp system according to the third embodiment. As shown in FIG. 6, in the vehicle lamp system 200 according to the present embodiment, the control unit 228R2 includes a first acceleration range P1 (+) and a second acceleration range P2 (+) that are predetermined for the acceleration of the vehicle 300. And a first acceleration range P1 (−) and a second deceleration range P2 (−) that are predetermined for the deceleration (negative acceleration) of the vehicle 300, and an acceleration range of a plot that is used to calculate a linear approximation formula (Hereinafter, this information is referred to as plot range information as appropriate). This plot range information is configured as a set of a range on the acceleration side and a range on the deceleration side. In the present embodiment, the plot range information includes a set of the first acceleration range P1 (+) and the first deceleration range P1 (-), a second acceleration range P2 (+), and the second deceleration range P2 (-). It consists of two sets. These acceleration range and deceleration range can be set based on the amount of time change of the vehicle speed detected by the vehicle speed sensor 312 or the magnitude of the vehicle longitudinal component obtained from the detected value of the acceleration sensor 316. The plot range information is stored, for example, in the memory 228R4.

  For example, the control unit 228R2 determines that the acceleration of the vehicle 300 is within the first acceleration range P1 (+) or the second acceleration range P2 (+) from the start to the stop of the vehicle 300, or the deceleration is the first. When the value is within the first deceleration range P1 (−) or the second deceleration range P2 (−), the detection value of the acceleration sensor 316 is recorded. Then, the control unit 228R2 calculates the linear approximation formula by plotting the detected values recorded at the coordinates with the acceleration in the vertical direction of the vehicle as a first axis and the acceleration in the vertical direction of the vehicle as a second axis. For example, the control unit 228R2 is in the first acceleration range P1 (+), the first deceleration range P1 (−), the second acceleration range P2 (+), and the second deceleration range P2 (−) while the vehicle 300 is traveling. A linear approximation formula is calculated when the detection values or plots of the acceleration sensor 316 are complete.

  And control part 228R2 performs the correction process of the optical axis O and the reference value of vehicle attitude angle (theta) v based on the change of the inclination of the obtained linear approximation formula at the arbitrary timings during vehicle travel. Specifically, control unit 228R2 calculates a vehicle attitude angle θv derived from a reference value of vehicle attitude angle θv and a slope of a linear approximation (a ratio of time variation of acceleration in the vehicle longitudinal direction and the vehicle vertical direction) An error component Δθe that is the difference between the two is derived. For example, the control unit 228R2 calculates the integrated value from the initial calculation of the change in inclination of the linear approximation formula to derive the vehicle attitude angle θv, and this vehicle attitude angle θv and the vehicle attitude angle θv held in the memory 228R4 The error component Δθe is obtained from the reference value. Alternatively, as in the second embodiment, the control unit 228R2 obtains the vehicle attitude angle θv from the inclination between the reference straight line approximate expression recorded in advance and the calculated straight line approximate expression, and uses the vehicle attitude angle θv and the memory 228R4. An error component Δθe is obtained from the reference value of the held vehicle attitude angle θv.

  Then, control unit 228R2 corrects the reference value of vehicle attitude angle θv such that error component Δθe becomes smaller. At this time, control section 228R2 corrects the reference value of vehicle attitude angle θv by correction value θc when the obtained absolute value of error component Δθe exceeds predetermined threshold value θth (| Δθe |> θth). . Further, the control unit 228R2 generates a control signal for adjusting the optical axis position by the correction value θc, and thereby corrects the optical axis position. Note that the control unit 228R2 may execute the above-described correction process immediately after the vehicle 300 is stopped.

  The “predetermined threshold θth” and the “correction value θc” are resolutions of optical axis control, detection accuracy of the error component Δθe, or detection resolution of the vehicle attitude angle θv using a change in inclination of a linear approximation formula. It is set according to etc. The predetermined threshold value θth is set within an error range that does not hinder optical axis control. The correction value θc is set in accordance with, for example, an error caused by the smallest error among the main error factors. As such an error factor, for example, variations in vehicle attitude under the same load condition, that is, variations in suspension displacement, etc. can be mentioned.

  The correction value θc is set to a value smaller than a predetermined threshold value θth. As a result, even when the detection accuracy of the error component Δθe is low, the reference value of the vehicle attitude angle θv can be gradually brought closer to a probable value. For example, the resolution of angle detection using the change in inclination of the linear approximation formula is 0.04 °, the threshold θth is set to 0.1 °, and the correction value θc is set to 0.03 °. Note that the “predetermined threshold value θth” and the “correction value θc” can be set as appropriate based on experiments and simulations by the designer.

  As described above, the plot range information is configured by combining the range on the acceleration side and the range on the deceleration side. In this way, by combining the range on the acceleration side and the range on the deceleration side, it is possible to cancel out the error component such as a change in vehicle attitude caused by acceleration and the error component such as a change in vehicle attitude caused by deceleration. A linear approximation formula can be calculated with higher accuracy. The first acceleration range P1 (+) and the first deceleration range P1 (−), and the second acceleration range P2 (+) and the second deceleration range P2 (−) are each, for example, a large acceleration / deceleration. The range of absolute values is set to be equal. As a result, an error component such as a vehicle posture change caused by acceleration and an error component such as a vehicle posture change caused by deceleration can be canceled out more, so that a linear approximation formula can be calculated with higher accuracy.

  In the present embodiment, the first acceleration range P1 (+) and the first deceleration range P1 (-) are set to be within a predetermined range of slow acceleration / deceleration. Further, the second acceleration range P2 (+) and the second deceleration range P2 (−) have a predetermined acceleration / deceleration greater than the first acceleration range P1 (+) and the first deceleration range P1 (−). The acceleration / deceleration range is set. In this embodiment, since the plot range information is set as the range of the slow acceleration / deceleration and the range of the rapid acceleration / deceleration, it is possible to calculate the linear approximation formula with higher accuracy than in the case of only one set of either. it can.

  It should be noted that linear approximation equations are independently used for the first acceleration range P1 (+) and the first deceleration range P1 (-), and the second acceleration range P2 (+) and the second deceleration range P2 (-). It may be calculated and the correction process may be executed based on the slope of each linear approximation formula. In this case, the calculation frequency of the set of the first acceleration range P1 (+) and the first deceleration range P1 (-) and the set of the second acceleration range P2 (+) and the second deceleration range P2 (-) Depending on the calculation accuracy, the weight of the correction may be different depending on the set, such as changing the magnitude of the correction value θc. Or you may perform a correction process based on the average of the inclination of the linear approximation formula calculated each independently. Furthermore, a set of the first acceleration range P1 (+) and the first deceleration range P1 (−), a set of the second acceleration range P2 (+) and the second deceleration range P2 (−) within a predetermined time. If the plots are aligned for these plots, a linear approximation formula is calculated using these plots, and if the plots for all the pairs are not aligned within the predetermined time, using the plots of the set in which the plots are aligned at that point A linear approximation may be calculated.

  The plot range information includes a set of the first acceleration range P1 (+) and the first deceleration range P1 (−), and a set of the second acceleration range P2 (+) and the second deceleration range P2 (−). You may be comprised only by either one. For example, the set of the first acceleration range P1 (+) and the first deceleration range P1 (−) set in the slow acceleration / deceleration range is the second acceleration range P2 (+) set in the sudden acceleration / deceleration range. Compared with the set of the second deceleration range P2 (−), the detection value of the acceleration sensor 316 is more frequently included in the range during traveling of the vehicle, so that the number of correction processes can be increased. The number of sets of acceleration ranges and deceleration ranges included in the plot range information may be three or more.

  Further, the first acceleration range P1 (+) and the first deceleration range P1 (-), and the second acceleration range P2 (+) and the second deceleration range P2 (-) respectively have acceleration / deceleration magnitudes. In addition to setting the ranges to be equal, the ranges of vehicle speed may be set to be equal. As a result, since the error component generated by acceleration and the error component generated by deceleration can be canceled each other, the linear approximation equation can be calculated more accurately. The range of the acceleration range and the deceleration range, the magnitude of the acceleration / deceleration, and the like can be appropriately set based on experiments and simulations by the designer.

  FIG. 7 is a flowchart of auto leveling control of the vehicular lamp system according to the third embodiment. This flow is repeatedly performed at a predetermined timing by the irradiation control unit 228R (control unit 228R2) when the ignition is turned on, for example, in a state where the execution of the auto leveling control mode is instructed by the light switch 304, Exit when is turned off.

  The control unit 228R2 determines whether the vehicle is traveling (S201). When the vehicle is traveling (Y in S201), the control unit 228R2 controls the first acceleration range P1 (+), the first deceleration range P1 (−), the second acceleration range P2 (+), and the second deceleration range. It is determined whether the detection value plots of the acceleration sensor 316 at P2 (−) are prepared (S202). If the plots are not aligned (N in S202), the control unit 228R2 avoids the optical axis adjustment (S203), and ends this routine. When the plots are aligned (Y in S202), the control unit 228R2 calculates a linear approximation (S204), and the vehicle attitude angle θv derived from the inclination of the linear approximation and the vehicle attitude recorded in the memory 228R4 An error component Δθe, which is a difference from the reference value of the angle θv, is calculated (S205).

  The control unit 228R2 determines whether the absolute value of the error component Δθe exceeds the threshold value θth (S206). When the absolute value of the error component Δθe exceeds the threshold value θth (Y in S206), the control unit 228R2 corrects the reference value and the optical axis position of the vehicle attitude angle θv by the correction value θc (S207). After that, the control unit 228R2 avoids the optical axis adjustment with respect to the change of the total angle θ obtained from the detection value of the acceleration sensor 316 (S203), and ends this routine. When the absolute value of the error component Δθe is equal to or smaller than the threshold θth (N in S206), the control unit 228R2 avoids the optical axis adjustment without executing the correction process (S203), and ends this routine.

  When the vehicle is not traveling (N in S201), the control unit 228R2 determines whether the vehicle is at a stop (S208). When the vehicle is stopped (Y in S208), the control unit 228R2 calculates the road surface angle θr (S209), records the calculated road surface angle θr as a new reference value (210), and avoids the optical axis adjustment (S203) and this routine is finished. When the vehicle is not stopped (N in S208), the control unit 228R2 calculates the vehicle attitude angle θv (S211), and the difference between the calculated vehicle attitude angle θv and the reference value of the vehicle attitude angle θv is a predetermined amount or more It is determined whether or not there is (S212). When the difference is less than the predetermined amount (N in S212), the control unit 228R2 avoids the optical axis adjustment (S203) and ends this routine. If the difference is equal to or greater than the predetermined amount (Y in S212), the controller 228R2 adjusts the optical axis position based on the calculated vehicle attitude angle θv (S213), and uses the calculated vehicle attitude angle θv as a reference value. Recording is performed (S214), and this routine is terminated.

  As described above, in the vehicle lamp system 200 according to the present embodiment, the control unit 228R2 plots the detection value of the acceleration sensor 316 when the acceleration of the vehicle 300 is in a predetermined range, and A linear approximation formula is calculated from a plot of detection values of the acceleration sensor 316 when the deceleration is within a predetermined range. Therefore, it is possible to cancel out an error component such as a change in vehicle attitude caused by acceleration and an error component such as a change in vehicle attitude caused by deceleration, so that a linear approximation formula having a slope closer to vehicle attitude angle θv should be calculated. Can do.

  In addition, the control unit 228R2 executes the correction process when a plot is obtained for a predetermined acceleration range and deceleration range. Therefore, for example, in the control in which the straight line approximate expression is calculated from the detection value of the acceleration sensor 316 recorded between the start and the stop of the vehicle 300 immediately after the vehicle is stopped, the correction process is executed. If an error occurs in the calculation of the vehicle attitude angle θv and the adjustment of the optical axis performed at the same time, the vehicle 300 may travel with the error included, but according to this embodiment, such a situation is avoided. be able to.

  The vehicle lamp system 200 according to each embodiment is an aspect of the present invention. The vehicle lamp system 200 includes a lamp unit 10 capable of adjusting the optical axis, an acceleration sensor 316, and irradiation control units 228L and 228R for controlling the lamp unit 10, and the irradiation control units 228L and 228R described above Execute automatic leveling control.

  As another aspect of the present invention, irradiation control units 228L and 228R as control devices can be cited. The irradiation control units 228L and 228R are reception units 228L1 and 228R1 for receiving accelerations in the vehicle longitudinal direction and vehicle vertical direction from the acceleration sensor 316, and control units 228L2 and 228R2 for executing the above-described auto-leveling control. The transmitters 228L3 and 228R3 for transmitting control signals generated by the controllers 228L2 and 228R2 to the leveling controller 236 are provided. The irradiation control unit 228 in the vehicle lamp system 200 corresponds to a control unit in a broad sense, and the control units 228L2 and 228R2 in the irradiation control unit 228 correspond to a control unit in a narrow sense.

  Still another aspect of the present invention is a vehicle lamp control method. This control method is based on the light of the lamp unit 10 based on the change in the ratio of the time change of acceleration in the longitudinal direction of the vehicle to the time change of acceleration in the vertical direction of the vehicle during at least one of acceleration and deceleration of the vehicle 300. Adjust the axis.

  The present invention is not limited to the above-described embodiments, and various modifications such as design changes may be added based on the knowledge of those skilled in the art or based on the knowledge of those skilled in the art. Also included within the scope of the present invention are embodiments that are modified or modified. New embodiments resulting from the combination of each of the above-described embodiments and the above-described embodiments with the following modifications have the respective effects of the combined embodiments and modifications.

  In the above-described embodiments, the irradiation control unit 228 may control the leveling actuator 226 as an optical axis adjustment unit without intervention of the leveling control unit 236. That is, the irradiation control unit 228 may function as the leveling control unit 236. In addition, the vehicle control unit 302 may perform the generation of the control signal that instructs the optical axis adjustment in each of the above-described embodiments. That is, the vehicle control unit 302 may constitute a control device that performs auto leveling control. In this case, the irradiation control unit 228 controls the driving of the leveling actuator 226 based on an instruction from the vehicle control unit 302.

  Also in the first embodiment, as in the third embodiment, the correction process using the predetermined threshold value θth and the correction value θc may be performed.

  Reference Signs List 10 lamp unit, 200 vehicle lamp system, 228, 228L, 228R irradiation control unit, 228L1, 228R1 receiving unit, 228L2, 228R2 control unit, 228L3, 228R3 transmitting unit, 300 vehicle, 316 acceleration sensor, O light axis, θ total Angle, θr Road surface angle, θv Vehicle attitude angle, α motion acceleration vector, β composite acceleration vector.

Claims (5)

A control device for a vehicle lamp, which generates a control signal for changing the irradiation direction of the vehicle lamp in the vertical direction of the vehicle based on information on a vehicle attitude angle,
Corrects the information on the vehicle attitude angle calculated or held while the vehicle is stopped based on the ratio between the change amount of acceleration in the vehicle longitudinal direction detected by the acceleration sensor while the vehicle is traveling and the change amount of acceleration in the vehicle vertical direction A control device for a vehicular lamp characterized by comprising: A control device for a vehicle lamp, which generates a control signal for changing the irradiation direction of the vehicle lamp in the vertical direction of the vehicle based on information on a vehicle attitude angle,
Based on the ratio of the amount of change in the X-axis numerical value associated with the longitudinal direction of the vehicle in the acceleration sensor and the amount of change in the numerical Z-axis associated with the vertical direction of the vehicle in the acceleration sensor A control device for a vehicle lamp, comprising: correcting information related to a vehicle attitude angle calculated or held while the vehicle is stopped. A control device for a vehicle lamp, which generates a control signal for changing the irradiation direction of the vehicle lamp in the vertical direction of the vehicle based on information on a vehicle attitude angle,
The acceleration in the longitudinal direction of the vehicle, which is obtained from at least two acceleration data in both the longitudinal direction and the longitudinal direction of the vehicle detected by the acceleration sensor while the vehicle is traveling, is set as the first axis, and the acceleration in the vertical direction of the vehicle is the second axis A control device for a vehicle lamp, comprising: correcting information related to a vehicle posture angle calculated or held while the vehicle is stopped based on an inclination of a straight line at the coordinates set to. A control device for a vehicle lamp, which generates a control signal for changing the irradiation direction of the vehicle lamp in the vertical direction of the vehicle based on information on a vehicle attitude angle,
The X-axis obtained from at least two pieces of acceleration data relating to both the X-axis associated with the vehicle longitudinal direction in the acceleration sensor and the Z-axis associated with the vehicle vertical direction in the acceleration sensor, detected during traveling of the vehicle. Based on the slope of the straight line at the coordinates where the numerical value is set to the first axis and the Z-axis numerical value is set to the second axis, the information on the vehicle attitude angle calculated or held while the vehicle is stopped is corrected. Control device for vehicle lamp.   The vehicle lamp control device according to claim 3 or 4, wherein the straight line is obtained by a least square method.

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