JP2012096664A - Device for controlling vehicular lamp, vehicular lamp system, and method for controlling vehicular lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new method of auto-leveling control for adjusting an optical axis by acquiring a vehicular inclination angle to a road surface from a detection value of an acceleration sensor.SOLUTION: This device for controlling a vehicular lamp includes: a reception part for receiving a vector output from an acceleration sensor 316; a control part for generating a control signal for acquiring a total angle θ from the gradient of the vector output from the acceleration sensor 316 while a vehicle stops, acquiring a road surface angle θr from the gradient of a motion acceleration vector α generated by the traveling of the vehicle, leading out a vehicle attitude angle θv from the total angle θ and the road surface angle θr, and using the led-out vehicle attitude angle θv to command optical axis adjustment of the vehicular lamp; and a transmission part for transmitting the control signal to an optical axis adjustment part of the vehicular lamp.

Description

  The present invention relates to a vehicular lamp control device, a vehicular lamp system, and a vehicular lamp control method, and more particularly to a vehicular lamp control device, a vehicular lamp system, and a vehicular lamp control method used in an automobile or the like. It is about.

  Conventionally, there has been known auto-leveling control in which an optical axis position of a vehicle headlamp is automatically adjusted in accordance with an inclination angle in a vehicle pitch direction to change an irradiation direction. In general, in the auto leveling control, a vehicle height sensor is used as a vehicle inclination detection device, and the optical axis position of the headlamp is adjusted based on the 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. Patent Document 4 discloses a configuration using an acceleration sensor that detects gravitational acceleration as an inclination 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 the acceleration sensor, the vehicle tilt angle with respect to the road surface is obtained from the vehicle tilt angle with respect to the horizontal plane obtained by the acceleration sensor, and the optical axis is obtained using the obtained vehicle tilt angle with respect to the road surface. Adjustments need to be made. On the other hand, the present inventor has come up with a new method of automatic leveling control that adjusts the optical axis by acquiring the vehicle inclination angle with respect to the road surface from the detection value of the acceleration sensor.

  The present invention has been made on the basis of such recognition by the inventor, and an object of the present invention is to obtain a new method of auto leveling control that adjusts the optical axis by acquiring the vehicle inclination angle with respect to the road surface from the detection value of the acceleration sensor. Is to provide.

  In order to solve the above-described problems, an aspect of the present invention is a control device for a vehicle lamp, and the control device includes a receiving unit for receiving a vector output from the acceleration sensor, and an acceleration sensor while the vehicle is stopped. The inclination angle of the vehicle with respect to the horizontal plane is obtained from the inclination of the vector output from the vehicle, the inclination angle of the road surface with respect to the horizontal plane is obtained from the inclination of the acceleration vector generated by the vehicle traveling, and the inclination angle of the vehicle with respect to the horizontal plane A control unit for deriving a tilt angle of the vehicle with respect to the road surface from the tilt angle, and generating a control signal instructing an optical axis adjustment of the vehicular lamp using the derived tilt angle of the vehicle with respect to the road surface, and a control signal A transmission unit for transmitting to the optical axis adjustment unit of the vehicular lamp.

  According to this aspect, it is possible to provide a new method of automatic leveling control that acquires the vehicle inclination angle with respect to the road surface from the detection value of the acceleration sensor and adjusts the optical axis.

  In the above aspect, the control unit generates a control signal based on the inclination angle of the vehicle with respect to the horizontal plane while the vehicle is stopped, and acquires the inclination angle of the road surface with respect to the horizontal plane from the inclination of the acceleration vector generated by the start when the vehicle starts. Then, the vehicle tilt angle with respect to the road surface may be derived, and the control signal may be generated using the derived vehicle tilt angle with respect to the road surface. According to this aspect, it is possible to simplify the auto leveling control while ensuring the driver's visibility.

  In the above aspect, the control unit obtains the inclination angle of the road surface with respect to the horizontal plane from the inclination of the acceleration vector generated by the traveling during traveling after the vehicle starts, derives the inclination angle of the vehicle with respect to the road surface, and derives the derived road surface The control signal may be generated using the inclination angle of the vehicle with respect to. According to this aspect, since the optical axis position can be corrected while the vehicle is traveling, the accuracy of the auto leveling control can be improved.

  In the above aspect, the control unit derives the optical axis adjustment amount of the vehicular lamp according to the acquired inclination angle of the road surface with respect to the horizontal plane, and when the derived optical axis adjustment amount is less than a predetermined threshold value, A control signal for instructing to avoid generation of the control signal or to maintain the optical axis position may be generated. According to this aspect, frequent optical axis adjustment can be avoided, and the control burden on the control unit can be reduced.

  In the above aspect, an upper limit may be set for the optical axis adjustment amount of the vehicular lamp, and the control unit may generate a control signal so that the optical axis adjustment amount of the vehicular lamp does not exceed the upper limit. According to this aspect, it is possible to prevent the optical axis from being raised or lowered too much, and in the optical axis adjustment based on the inclination angle of the vehicle with respect to the horizontal plane performed while the vehicle is stopped, the optical axis position is It is possible to reduce the amount of deviation when it deviates from the appropriate position.

  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 obtains the inclination angle of the vehicle with respect to the horizontal plane from the inclination of the vector output from the acceleration sensor while the vehicle is stopped, and obtains the inclination angle of the road surface with respect to the horizontal plane from the inclination of the acceleration vector generated by the traveling of the vehicle. And deriving the vehicle inclination angle relative to the road surface from the vehicle inclination angle relative to the horizontal plane and the road surface inclination angle relative to the horizontal plane, and adjusting the optical axis of the vehicle lamp using the derived vehicle inclination angle relative to the road surface. Features.

  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, The vehicle inclination angle with respect to the horizontal plane is obtained from the inclination of the vector output from the acceleration sensor while the vehicle is stopped, and the inclination angle of the road surface with respect to the horizontal plane is obtained from the inclination of the acceleration vector generated by the traveling of the vehicle. A vehicle inclination angle with respect to the road surface is derived from the angle and an inclination angle of the road surface with respect to a horizontal plane, and the optical axis of the vehicle lamp is adjusted using the derived vehicle inclination angle with respect to the road surface.

  Also according to these aspects, it is possible to provide a new method of auto leveling control in which the inclination angle of the vehicle with respect to the road surface is acquired from the detection value of the acceleration sensor and the optical axis is adjusted.

  ADVANTAGE OF THE INVENTION According to this invention, the new method of the automatic leveling control which acquires the inclination angle of the vehicle with respect to a road surface from the detection value of an acceleration sensor, and adjusts an optical axis 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. It is a schematic diagram for demonstrating the auto leveling control by the vehicle lamp system which concerns on Embodiment 1. FIG. It is a schematic diagram for demonstrating the auto leveling control by the vehicle lamp system which concerns on Embodiment 1. FIG. 3 is an auto-leveling control flowchart of the vehicular lamp system according to the first embodiment.

  The present invention will be described below 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 repeated descriptions are omitted as appropriate. The embodiments do not limit the invention but are exemplifications, and all 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 vehicular lamp system according to the first embodiment. The vehicular lamp system 200 according to the present embodiment is a variable light distribution headlamp system in which a pair of headlamp units formed symmetrically are arranged one by one on the left and right in the vehicle width direction of the vehicle. Since the left and right headlamp units have substantially the same configuration except that they have a symmetrical structure, the structure of the right headlamp unit 210R will be described below, and the left headlamp will be described. The description of the unit is omitted as appropriate. In addition, when describing each member of the left headlamp unit, the same reference numerals as those of the corresponding member of the headlamp unit 210R are attached to each member for convenience of explanation.

  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 that can be removed when the bulb 14 is replaced on the rear side of the vehicle. A lamp chamber 216 is formed by the lamp body 212 and the translucent cover 214. The lamp chamber 216 houses a lamp unit 10 (vehicle lamp) that emits light toward the front of the vehicle.

  A lamp bracket 218 having a pivot mechanism 218 a serving as a swing center in the vertical and horizontal directions of the lamp unit 10 is formed in a part of the lamp unit 10. 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 by the adjustment state of the aiming adjustment screw 220, and the forward tilt posture or the backward tilt posture with the pivot mechanism 218a as the center with respect to the position. The posture can be changed. A rotating shaft 222a of a swivel actuator 222 for constituting a curved road light distribution variable headlamp that illuminates the traveling direction when traveling on a curved road is fixed to the lower surface of the lamp unit 10. The swivel actuator 222 is fixed to the unit bracket 224.

  A leveling actuator 226 disposed outside the lamp body 212 is connected to the unit bracket 224. The leveling actuator 226 is composed of, for example, a motor that expands and contracts the rod 226a 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 in a backward tilted posture with the pivot mechanism 218a as the center. Conversely, when the rod 226a is shortened in the direction of the arrow N, the lamp unit 10 swings so as to assume a forward leaning posture with the pivot mechanism 218a as the center. When the lamp unit 10 is tilted backward, leveling adjustment can be performed so that the pitch angle of the optical axis O, that is, the vertical angle 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.

  On the inner wall surface of the lamp chamber 216 below the lamp unit 10, an irradiation control unit 228 (control unit, control device) that performs lighting on / off control of the lamp unit 10, light distribution pattern formation control, optical axis adjustment of the lamp unit 10, etc. ) Is 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. In addition, the aiming adjusting screw 220 described above is disposed on the lamp bracket 218 at an interval in the vehicle width direction. Then, by rotating the two aiming adjusting screws 220, the lamp unit 10 can be turned up and down and left and right around the aiming pivot mechanism, and the optical axis O can be adjusted up and down and left and right. This aiming adjustment is performed, for example, at the time of vehicle shipment, vehicle inspection, or replacement of the headlamp unit 210R. The headlamp unit 210R is adjusted to a posture determined by design, and the light distribution pattern formation control and the optical axis position adjustment control are performed based on this posture.

  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 that supports a reflector 16 on an 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 constituted 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 that can rotate around the rotary shaft 12a, and includes a cutout portion that is partially cut away in the axial direction and a plurality of shade plates (not shown). Either the notch or the shade plate is moved on 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 the optical axis O extending in the vehicle front-rear direction. The bulb 14 is arranged behind 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 surface and a flat rear surface, and a virtual vertical screen in front of the vehicle lamp system 200 as a reverse image of a light source image formed on the rear focal plane. 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 controller 228R of the headlamp unit 210R includes a receiver 228R1, a controller 228R2, a transmitter 228R3, and a memory 228R4. The irradiation control unit 228R controls the power supply circuit 230 based on information obtained from the vehicle control unit 302 mounted on the vehicle 300, and performs lighting control of the bulb 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 types of information transmitted from the vehicle control unit 302, including vectors output from the acceleration sensor 316, are received by the receiving unit 228R1, and the control unit 228R2 uses the information and information stored in the memory 228R4 as necessary. Various control signals are generated. Then, the control unit 228R3 transmits the control signal to the power supply circuit 230, the variable shade control unit 232, the swivel control unit 234, the leveling control unit 236, and the like of the lamp unit 10. The memory 228R4 is, for example, a nonvolatile memory.

  The variable shade control unit 232 controls the rotation of the motor 238 connected to the rotary shaft 12a of the rotary shade 12, and moves a desired shade plate or notch portion onto 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. This automatic light distribution pattern formation control is executed when, for example, the light switch 304 instructs automatic light distribution pattern formation control.

  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 by the image processing unit 308, and the recognition result is provided to the vehicle control unit 302. 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 controllers 228L and 228R can select a light distribution pattern to be formed according to the traveling state and posture of the vehicle 300, and can 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. Since the control performed by the irradiation control unit 228L and the control performed by the irradiation control unit 228R are the same, only the irradiation control unit 228R side will be described here, and the description of the irradiation control unit 228L side will be omitted.

  FIGS. 3 and 4 are schematic diagrams for explaining auto-leveling control by the vehicle lamp system according to the first embodiment. FIG. 3 shows the relationship between the gravitational acceleration vector G, the motion acceleration vector α, and the combined acceleration vector β, and the relationship between the total angle θ, the road surface angle θr, and the vehicle attitude angle θv. FIG. 4 shows changes with time of the vehicle speed V and the total angle θ.

  For example, when a load is placed in the luggage compartment at the rear of the vehicle or there is an occupant in the rear seat, the vehicle posture is tilted backward, and when the load is lowered or the occupant in the rear seat gets off, the vehicle posture is in a backward tilted state. 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 unit 228R receives the vector output from the acceleration sensor 316 via the vehicle control unit 302, detects the inclination angle in the pitch direction of the vehicle 300 from the received vector, and passes through the leveling control unit 236. The leveling actuator 226 is controlled so that the pitch angle of the optical axis O is an angle corresponding to the vehicle posture. In this way, by performing auto leveling control that performs leveling adjustment of the lamp unit 10 in real time based on the vehicle posture, even if the vehicle posture changes according to the usage state of the vehicle 300, the front irradiation reachable distance is optimally adjusted. 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. . As shown in FIG. 3, the acceleration sensor 316 detects the inclination of the vehicle 300 with respect to the gravitational acceleration vector G, and outputs numerical values of the respective axis components of the gravitational acceleration vector G in the three-axis directions. That is, the acceleration sensor 316 calculates the total angle θ, which is the vehicle inclination angle with respect to the horizontal plane, including the road surface angle θr, which is the inclination angle of the road surface with respect to the horizontal plane, and the vehicle attitude angle θv, which is the vehicle inclination angle with respect to the road surface. Can be detected as Further, the acceleration sensor 316 detects a combined acceleration vector β obtained by combining a gravitational acceleration vector G and a motion acceleration vector α that is an acceleration vector generated by the traveling of the vehicle 300 during acceleration / deceleration of the vehicle 300, and performs triaxial directions. The numerical value of each axis component of the resultant acceleration vector β at is output. Note that the road surface angle θr, the vehicle attitude angle θv, and the total angle θ are angles in the vertical direction of the X axis, in other words, angles in the pitch direction of the vehicle 300. In the following description, the component of the acceleration sensor 316 in the Y axis direction, that is, the angle of the vehicle 300 in the roll direction is not considered.

  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. Therefore, in order to perform auto leveling control using the acceleration sensor 316, it is necessary to extract the vehicle attitude angle θv from the total angle θ obtained from the acceleration sensor 316.

  Therefore, in the automatic leveling control according to the present embodiment, the irradiation control unit 228 acquires the total angle θ from the gradient of the vector output from the acceleration sensor 316 while the vehicle is stopped, and the motion acceleration vector α generated by the traveling of the vehicle 300 The road surface angle θr is obtained from the slope of the road. Then, the irradiation control unit 228 derives the vehicle posture angle θv from the total angle θ and the road surface angle θr, and adjusts the optical axis O of the lamp unit 10 using the derived vehicle posture angle θv. Since the vehicle 300 moves parallel to the road surface, the motion acceleration vector α is a vector parallel to the road surface regardless of the vehicle attitude angle θv. Therefore, the road surface angle θr can be acquired from the inclination of the motion acceleration vector α.

  Specifically, for example, in a vehicle manufacturer's manufacturing factory or dealer's maintenance factory, the vehicle 300 is placed on a horizontal plane to be in a reference state. The reference state is, for example, a state that should be taken when one person gets on the driver's seat of the vehicle 300 or when one person gets on the driver's seat. 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 receiving the initialization signal, the controller 228R2 records the output vector of the acceleration sensor 316 received by the receiver 228R1 as a reference vector in the memory 228R4. In addition, the control unit 228R2 performs initial aiming adjustment using this reference vector as necessary.

  In a situation where the vehicle 300 is actually used, the control unit 228R2 receives a vector repeatedly output from the acceleration sensor 316 at a predetermined interval and records it in the memory 228R4. Then, the irradiation control unit 228R calculates a total angle θ that is an angle formed by a vector corresponding to the gravitational acceleration vector G output from the acceleration sensor 316 and a reference vector recorded in the memory 228R4 while the vehicle is stopped. Based on the total angle θ, a control signal for instructing the optical axis adjustment of the lamp unit 10 is generated. The generated control signal is transmitted to the leveling control unit 236 by the transmission unit 228R3. The leveling control unit 236 controls the leveling actuator 226 according to the control signal. As a result, the optical axis O is adjusted to an angle corresponding to the total angle θ. The calculated total angle θ is recorded in the memory 228R4.

  The “stopping vehicle” is, for example, from when the detection value of the vehicle speed sensor 312 becomes 0 to when it exceeds 0. Further, the control unit 228R2 calculates the total angle θ when the posture of the vehicle 300 is stabilized after the detection value of the vehicle speed sensor 312 becomes zero. Control unit 228R2 can determine that the posture of vehicle 300 is stable when the output value of acceleration sensor 316 is stable. The “when the output value of the acceleration sensor 316 is stabilized” may be, for example, when the change amount per unit time of the output value of the acceleration sensor 316 is equal to or less than a predetermined amount, or the detection value of the vehicle speed sensor 312 is 0. It may be after a predetermined time has elapsed since then. The “during vehicle stop”, “predetermined amount”, and “predetermined time” can be appropriately set based on experiments and simulations by the designer.

Irradiation control unit 228R derives a motion acceleration vector α generated by starting as a vector of acceleration generated by traveling of vehicle 300 when the vehicle starts. This motion acceleration vector α is derived by subtracting the gravitational acceleration vector G output from the acceleration sensor 316 immediately before starting from the combined acceleration vector β output from the acceleration sensor 316 immediately after starting. As shown in FIG. 4, the “immediately before starting” is, for example, after the detected value of the vehicle speed sensor 312 becomes 0 and the output value of the acceleration sensor 316 is stabilized, than the predetermined time period T ₂ to change occurs is a predetermined time period T ₁ of the previous. The "Immediately after starting" is, for example, a predetermined time period T ₃ from the vehicle starting time t _s. The predetermined period _{T 1} is, for example, 1-2 seconds. Predetermined time period _{T 2} are, for example, from 1 to 2 seconds before the vehicle start time _{t s} until the vehicle start time _{t s.} Predetermined time period _{T 3} is, for example, 2 to 3 seconds.

For example, the control unit 228R2, when the detected value of the vehicle speed sensor 312 exceeds 0, and detects that the vehicle is starting to recognize that time as the vehicle start time t _s, the acceleration in a predetermined period T ₁ A vector obtained by averaging the output values of the sensor 316 is acquired as a gravitational acceleration vector G used for deriving the motion acceleration vector α. The control unit 228R2 obtains a combined acceleration vector using a vector obtained by averaging the output values of the acceleration sensor 316 in a predetermined period T ₃ in the derivation of motion acceleration vector alpha beta. Then, the control unit 228R2 derives the motion acceleration vector α by subtracting the acquired gravitational acceleration vector G from the acquired combined acceleration vector β.

The control unit 228R2 acquires the road surface angle θr from the derived gradient of the motion acceleration vector α. The road surface angle θr is obtained by calculating the arc tangent of the vertical direction component and the horizontal direction component of the motion acceleration vector α. The control unit 228R2 repeatedly calculates the road surface angle θr in a predetermined time period T _3, the average angle of the calculated road surface angle θr may be used as the road surface angle θr used to adjust the optical axis. Then, the controller 228R2 derives the vehicle attitude angle θv from the obtained road surface angle θr and the total angle θ recorded in the memory 228R4, and uses the derived vehicle attitude angle θv to adjust the optical axis. Generate a control signal. The control unit 228R2 calculates a total angle θ from the gravitational acceleration vector G used to derive the motion acceleration vector α and the reference vector stored in the memory 228R4, and uses the total angle θ to determine the vehicle attitude angle. θv may be derived.

  The control unit 228R2 performs the following control when deriving the vehicle attitude angle θv and generating a control signal for optical axis adjustment. That is, the control unit 228R2 determines a correction value according to the acquired road surface angle θr. This correction value is a difference (optical axis adjustment amount) between the optical axis position adjusted while the vehicle is stopped and the optical axis position determined based on the obtained road surface angle θr or vehicle attitude angle θv. In this embodiment, since the optical axis position is adjusted according to the total angle θ while the vehicle is stopped, the correction value is the road surface angle θr itself. When the correction value is equal to or greater than the predetermined threshold value, the control unit 228R2 derives the current vehicle attitude angle θv by subtracting the correction value from the total angle θ, and performs the optical axis adjustment. When the correction value is less than the predetermined threshold value, the control unit 228R2 avoids the adjustment of the optical axis by generating a control signal for instructing the generation of the control signal or maintaining the optical axis position. In this way, by executing the optical axis adjustment when the correction value is equal to or greater than a predetermined threshold, frequent optical axis adjustment can be avoided, and as a result, the control burden on the control unit 228R2 can be reduced. The life of the leveling actuator 226 can be extended.

  The threshold value for determining whether or not to perform optical axis adjustment can be set as appropriate based on experiments and simulations by the designer. Further, the threshold value is determined when the vehicle 300 is on an uphill, that is, when the lamp unit 10 faces upward on the inclined road surface, and when the vehicle 300 is on a downhill, that is, on the road surface on which the lamp unit 10 is inclined. It may be different depending on the case of facing downward. For example, when the vehicle 300 is uphill, the optical axis position is shifted downward from the appropriate position by the optical axis adjustment based on the total angle θ while the vehicle is stopped, and when the vehicle 300 is downhill, the light when the vehicle is stopped Adjusting the axis shifts the optical axis position above the appropriate position. Therefore, when the vehicle 300 is on an uphill, the visibility of the driver is lower than when the vehicle 300 is on a downhill. Therefore, when priority is given to ensuring the visibility of the driver, the threshold value for the uphill is set smaller than the threshold value for the downhill. For example, the threshold for an uphill is 0.7% (0.4 °), and the threshold for a downhill is −1.5% (−0.9 °). Whether the vehicle 300 is uphill or downhill can be determined from the slope of the road surface angle θr acquired when the vehicle starts.

  The control unit 228R2 derives the inclination of the motion acceleration vector α generated by traveling during traveling after the vehicle starts. For example, when the amount of change in the detection value of the vehicle speed sensor 312 reaches a constant rate for a predetermined time (hereinafter, this state is referred to as a steady acceleration state as appropriate), the control unit 228R2 outputs the combined acceleration vector output from the acceleration sensor 316. The size and direction of β (the inclination with respect to the vertical and horizontal directions) are derived. In addition, the control unit 228R2 derives the magnitude of the motion acceleration vector α from the detection value of the vehicle speed sensor 312. Then, the control unit 228R2 uses the cosine theorem to calculate the horizontal direction of the motion acceleration vector α from the size and direction of the resultant acceleration vector β, the size of the motion acceleration vector α, and the known size of the gravity acceleration vector G. Deriving the slope. In addition, the gradient of the gravity acceleration vector G with respect to the Z axis of the acceleration sensor 316 is derived. The gravitational acceleration vector G corresponds to a vector output from the acceleration sensor 316 while the vehicle is stopped, and its inclination with respect to the Z axis corresponds to the total angle θ. The “running after the vehicle starts” is, for example, from the end of the optical axis adjustment when the vehicle starts until the detection value of the vehicle speed sensor 312 becomes zero. Further, the “when the vehicle starts” and the “running after the vehicle starts” are collectively referred to as “running the vehicle”.

  The control unit 228R2 acquires the road surface angle θr from the obtained gradient of the motion acceleration vector α. Then, the controller 228R2 derives the vehicle attitude angle θv by subtracting the road surface angle θr from the derived total angle θ. Then, when the difference between the optical axis position determined based on the derived vehicle attitude angle θv and the current optical axis position is a correction value, and the correction value exceeds a predetermined threshold value, the derived vehicle attitude angle θv Is used to adjust the optical axis. By executing the optical axis adjustment when the correction value exceeds the predetermined threshold value in this way, frequent optical axis adjustment can be avoided, and as a result, the control burden on the control unit 228R2 can be reduced. The life of the leveling actuator 226 can be extended. The “threshold value” can be appropriately set based on an experiment or simulation by a designer.

  The irradiation control unit 228R performs the optical axis adjustment by the above-described automatic leveling control when the lamp unit 10 is turned on, and does not perform the optical axis adjustment when the lamp unit 10 is turned off.

  FIG. 5 is an automatic leveling control flowchart of the vehicular lamp system according to the first embodiment. In the flowchart of FIG. 5, the processing procedure of each unit is displayed by a combination of S (acronym for 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 executed at a predetermined timing by the irradiation control unit 228R (control unit 228R2) when the ignition is turned on in the state in which the execution of the auto leveling control mode is instructed by the light switch 304, for example. Exit if is turned off.

  First, the control unit 228R2 determines whether the vehicle is traveling (S101). When the vehicle is not traveling (N in S101), the control unit 228R2 determines whether the vehicle posture is stable (S102). When the vehicle posture is not stable (N in S102), the control unit 228R2 does not generate a control signal instructing the optical axis adjustment, avoids the optical axis adjustment, and ends this routine. When the vehicle posture is stable (Y in S102), the control unit 228R2 calculates the total angle θ from the vector output from the acceleration sensor 316, and performs control for instructing optical axis adjustment based on the total angle θ. A signal is generated (S103). Then, the control unit 228R2 determines whether the lamp unit 10 is lit based on, for example, a signal from the light switch 304 (S104). When the lamp unit 10 is not lit (N in S104), the control unit 228R2 avoids the optical axis adjustment and ends this routine. When the lamp unit 10 is lit (Y in S104), the control unit 228R2 performs the optical axis adjustment (S105) and ends this routine.

  When the vehicle is running (Y in S101), the control unit 228R2 determines whether the vehicle is starting or in a steady acceleration state (S106). When the vehicle starts or is in a steady acceleration state (Y in S106), the control unit 228R2 acquires the road surface angle θr from the inclination of the motion acceleration vector α generated by the travel (S107), and determines a correction value (S108). Subsequently, the control unit 228R2 determines whether the correction value is equal to or greater than a predetermined threshold value (S109). When the correction value is equal to or greater than the predetermined threshold (Y in S109), the control unit 228R2 generates a control signal (S103) and determines whether the lamp unit 10 is lit (S104). If the lamp unit 10 is not lit (N in S104), this routine is terminated by avoiding the optical axis adjustment. If the lamp unit 10 is lit (Y in S104), the optical axis adjustment is performed. (S105) and this routine is finished.

  When the vehicle starts or is not in a steady acceleration state (N in S106) and when the correction value is not equal to or greater than a predetermined threshold (N in S109), the control unit 228R2 does not generate a control signal and avoids optical axis adjustment. Then, this routine is finished.

  For the left headlamp unit 210L, the irradiation control unit 228L (control unit 228L2) performs the same control. Alternatively, one of the irradiation controllers 228L and 228R may generate a control signal, and the other may acquire the generated control signal and adjust the optical axis O.

  As described above, the vehicle lamp system 200 according to the present embodiment acquires the total angle θ from the gradient of the vector output from the acceleration sensor 316 while the vehicle is stopped, and the motion acceleration vector α generated by the traveling of the vehicle 300. The road surface angle θr is obtained from the inclination of the vehicle, the vehicle attitude angle θv is derived from the total angle θ and the road surface angle θr, and the optical axis adjustment is performed using the derived vehicle attitude angle θv. Therefore, the vehicular lamp system 200 according to the present embodiment can provide a new method of auto leveling control that acquires the vehicle attitude angle θv from the detection value of the acceleration sensor 316 and adjusts the optical axis.

  For example, in the case of control in which the reference value of the road surface angle θr or the vehicle posture angle θv is held and the reference value of the road surface angle θr or the vehicle posture angle θv is rewritten in accordance with the change in the output value of the acceleration sensor 316, There is a possibility that an adjustment error increases due to repeated rewriting of the reference value. On the other hand, in the vehicle lamp system 200 according to the present embodiment, the road surface angle θr is obtained from the motion acceleration vector α generated by traveling of the vehicle, and the vehicle attitude angle θv is derived using the road surface angle θr to obtain the optical axis. Adjustment is being carried out. That is, since the road surface angle θr and the vehicle attitude angle θv are derived independently from the past control state at the time of starting, stopping, or constant acceleration / deceleration of the vehicle 300, such an adjustment error increases. The optical axis can be adjusted without any problems. Therefore, the accuracy of auto leveling control can be improved.

  Further, the vehicle lamp system 200 performs the optical axis adjustment based on the total angle θ while the vehicle is stopped, acquires the road surface angle θr from the inclination of the motion acceleration vector α, and starts the vehicle attitude angle θv. And the optical axis adjustment is performed based on the vehicle attitude angle θv. Since the necessity of ensuring the visibility of the driver is relatively low while the vehicle is stopped, the optical axis adjustment based on the total angle θ can be permitted while the vehicle is stopped. Therefore, the auto-leveling control can be simplified by performing the optical axis adjustment based on the total angle θ while the vehicle is stopped and omitting the derivation of the vehicle attitude angle θv. Then, by performing the optical axis adjustment based on the vehicle attitude angle θv when the vehicle starts, it is possible to ensure the visibility of the driving vehicle while the vehicle is traveling. Therefore, according to the vehicular lamp system 200 according to the present embodiment, the auto leveling control can be simplified while achieving the visibility of the driver, which is the purpose of the auto leveling control.

  In addition, the vehicle lamp system 200 obtains the road surface angle θr from the inclination of the motion acceleration vector α, derives the vehicle attitude angle θv, and derives the light based on the vehicle attitude angle θv during traveling after the vehicle starts. Axis adjustment is performed. As a result, the optical axis position can be corrected while the vehicle is traveling, so that the accuracy of the automatic leveling control can be improved.

  The vehicle lamp system 200 according to the above-described embodiment is an aspect of the present invention. The vehicular lamp system 200 includes a lamp unit 10 that can adjust an 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 auto 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 a vector output from the acceleration sensor 316, control units 228L2 and 228R2 for executing the above-described auto leveling control, and control units 228L2 and 228R2 Are provided with transmitting units 228L3 and 228R3 for transmitting the control signal generated by the above to the leveling control unit 236. The irradiation control units 228L and 228R in the vehicular lamp system 200 correspond to a control unit in a broad sense, and the control units 228L2 and 228R2 in the irradiation control units 228L and 228R correspond to a control unit in a narrow sense.

  Still another aspect of the present invention is a vehicle lamp control method. In this control method, the total angle θ is acquired from the inclination of the vector output from the acceleration sensor 316 while the vehicle is stopped, the road surface angle θr is acquired from the inclination of the motion acceleration vector α generated by the traveling of the vehicle, and the total angle θ The vehicle attitude angle θv is derived from the road surface angle θr, and the optical axis O of the lamp unit 10 is adjusted using the derived vehicle attitude angle θv.

  The present invention is not limited to the above-described embodiments, and various modifications such as design changes can be added based on the knowledge of those skilled in the art, and the embodiments to which such modifications are added are also described in the present invention. It is included in the scope of the invention. A new embodiment obtained by adding the following modifications to the above-described embodiment has the effects of the embodiments and the modifications.

  In the embodiment described above, the number of optical axis adjustments performed while the vehicle is running may be limited. For example, the optical axis adjustment during the traveling of the vehicle is performed only once during one traveling of the vehicle 300. Alternatively, the above-described threshold value is set so that the value at the time of the (n + 1) th optical axis adjustment is larger than that at the time of the nth optical axis adjustment. 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 “running once” is, for example, a period from when the detected value of the vehicle speed sensor 312 exceeds 0 to when the detected value of the vehicle speed sensor 312 becomes 0. This “running once” can be set as appropriate based on experiments and simulations by the designer.

  In the above-described embodiment, an upper limit may be set for the optical axis adjustment amount of the lamp unit 10. The upper limit information of the optical axis adjustment amount is recorded in, for example, the memory 228R4, and the control unit 228R2 generates a control signal so that the optical axis adjustment amount does not exceed the upper limit. As a result, it is possible to prevent the optical axis O from being raised or lowered too much. As a result, in the optical axis adjustment based on the total angle θ performed while the vehicle is stopped, the optical axis position is an appropriate position. It is possible to reduce the amount of deviation in the case of deviation. As a result, it is possible to reduce the driver's visibility and the possibility of giving glare to other vehicles. For example, the upper limit when the optical axis O is adjusted upward is determined so as not to exceed the optical axis position set by the initial aiming adjustment. Further, the upper limit when adjusting the optical axis O in the downward direction is an adjustment necessary for returning the optical axis O to the position set by the initial aiming adjustment in a state where the vehicle 300 is in the maximum backward tilt posture on the horizontal plane. The amount is the amount obtained by subtracting the difference between the upper limit position of the optical axis range determined based on the standard or the law and the position set by the initial aiming adjustment. Note that a range in which the displacement of the optical axis O of the lamp unit 10 is allowed is determined, and the control unit 228R2 may generate a control signal so that the optical axis O does not exceed the range.

  In the above-described embodiment, the irradiation controllers 228L and 228R may control the leveling actuator 226 as an optical axis adjuster without using the leveling controller 236. That is, the irradiation controllers 228L and 228R may function as the leveling controller 236. In addition, the vehicle control unit 302 may generate the control signal instructing the optical axis adjustment in the above-described embodiment. That is, the vehicle control unit 302 may constitute a control device that performs auto leveling control. In this case, the irradiation controllers 228L and 228R control the driving of the leveling actuator 226 based on an instruction from the vehicle controller 302.

  O optical axis, θ total angle, θr road surface angle, θv vehicle attitude angle, G gravitational acceleration vector, α motion acceleration vector, β composite acceleration vector, 10 lamp unit, 200 vehicle lamp system, 228, 228L, 228R irradiation control unit 228L1, 228R1 receiving unit, 228L2, 228R2 control unit, 228L3, 228R3 transmission unit, 236 leveling control unit, 300 vehicle, 316 acceleration sensor.

Claims (7)

A receiving unit for receiving a vector output from the acceleration sensor;
The inclination angle of the vehicle with respect to the horizontal plane is acquired from the inclination of the vector output from the acceleration sensor while the vehicle is stopped, the inclination angle of the road surface with respect to the horizontal plane is acquired from the inclination of the acceleration vector generated by the vehicle traveling, and the vehicle Deriving a vehicle inclination angle with respect to the road surface from the inclination angle and the inclination angle of the road surface with respect to the horizontal plane, and generating a control signal for instructing the optical axis adjustment of the vehicular lamp using the derived vehicle inclination angle with respect to the road surface A control unit of
A transmission unit for transmitting the control signal to the optical axis adjustment unit of the vehicular lamp;
A control device for a vehicular lamp, comprising:   The control unit generates the control signal based on the inclination angle of the vehicle with respect to the horizontal plane while the vehicle is stopped, and acquires the inclination angle of the road surface with respect to the horizontal plane from the inclination of the acceleration vector generated by the start at the start of the vehicle. The control device according to claim 1, wherein an inclination angle of the vehicle with respect to the road surface is derived, and the control signal is generated using the derived inclination angle of the vehicle with respect to the road surface.   The control unit obtains an inclination angle of the road surface with respect to the horizontal plane from an inclination of an acceleration vector generated by running during driving after starting the vehicle, derives an inclination angle of the vehicle with respect to the road surface, and The control device according to claim 1, wherein the control signal is generated using an inclination angle of a vehicle.   The control unit derives an optical axis adjustment amount of the vehicular lamp according to the acquired inclination angle of the road surface with respect to the horizontal plane, and when the derived optical axis adjustment amount is less than a predetermined threshold, the control signal 4. The control device according to claim 1, wherein a control signal for instructing to avoid generation of an optical axis or to maintain an optical axis position is generated. 5. An upper limit is set for the optical axis adjustment amount of the vehicular lamp,
The control device according to any one of claims 1 to 4, wherein the control unit generates the control signal so that an optical axis adjustment amount of the vehicular lamp does not exceed the upper limit. A vehicular lamp with an adjustable optical axis;
An acceleration sensor;
A control unit for controlling the vehicular lamp,
The control unit obtains the inclination angle of the vehicle with respect to the horizontal plane from the inclination of the vector output from the acceleration sensor while the vehicle is stopped, and obtains the inclination angle of the road surface with respect to the horizontal plane from the inclination of the acceleration vector generated by the traveling of the vehicle. The vehicle tilt angle with respect to the road surface is derived from the vehicle tilt angle with respect to the horizontal plane and the road surface tilt angle with respect to the horizontal plane, and the optical axis of the vehicle lamp is adjusted using the derived vehicle tilt angle with respect to the road surface. A vehicle lamp system characterized by the above. A vehicle lamp control method for adjusting an optical axis of a vehicle lamp using an acceleration sensor,
The inclination angle of the vehicle with respect to the horizontal plane is acquired from the inclination of the vector output from the acceleration sensor while the vehicle is stopped, the inclination angle of the road surface with respect to the horizontal plane is acquired from the inclination of the acceleration vector generated by the vehicle traveling, and the vehicle A vehicle inclination angle is derived from an inclination angle and an inclination angle of the road surface with respect to the horizontal plane, and the optical axis of the vehicle lamp is adjusted using the vehicle inclination angle with respect to the derived road surface. How to control the lamp.

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