Vehicle condition identification device and method, vehicle lamp light axis control device and method, vehicle lamp system

Abstract

To provide a vehicle state identification device capable of more accurately identifying a vehicle state and executing optical axis control in accordance with the identified vehicle state.SOLUTION: This vehicle state identification device comprises a controller 10 connected to an angular velocity sensor 11 and an acceleration sensor 12. The controller 10 acquires acceleration for each unit time at an axis corresponding to the longitudinal direction of a vehicle from the acceleration sensor 12 to calculate an acceleration change amount of the acceleration over a fixed period, acquires an angular velocity for each unit time at one of a roll axis and a pitch axis of the vehicle from the angular velocity sensor 11 to calculate an angular velocity change amount of the angular velocity over a fixed period, determines that the vehicle is in a first state when the acceleration change amount is equal or larger than a first threshold value and the angular velocity change amount is larger than a second threshold value, determines that the vehicle is in a second state different from the first state when the acceleration change amount is smaller than the first threshold value and the angular velocity change amount is equal to or smaller than the second threshold value, and outputs the determination result.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a vehicle condition identification device and method, a light axis control device and method for a vehicle lamp, and a vehicle lamp system. [Background technology]

[0002] Japanese Patent Publication No. 2008-032591 (Patent Document 1) describes a technology that uses a gyro sensor to detect when a vehicle starts to move or stops. In addition, Japanese Patent Publication No. 2018-062185 (Patent Document 2) describes a technology that uses an acceleration sensor to determine the use state of a vehicle (start of movement, parking). In addition, Japanese Patent Publication No. 4968841 (Patent Document 3) describes a technology that controls the adjustment of the optical axis of the headlights only when the opening and closing state of an opening and closing part such as a door is in the "open state." [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-032591 A [Patent Document 2] JP 2018-062185 A [Patent Document 3] Patent No. 4968841 Summary of the Invention [Problem to be solved by the invention]

[0004] One object of a specific embodiment of the present disclosure is to identify a vehicle state with greater accuracy. Another object of the specific embodiment of the present disclosure is to perform light axis control according to the vehicle state. [Means for solving the problem]

[0005] [1] An apparatus according to one aspect of the present disclosure, A device for identifying a state of a vehicle, comprising: A controller connected to the angular velocity sensor and the acceleration sensor, The controller: An acceleration per unit time on an axis corresponding to a front-rear direction of the vehicle is acquired from the acceleration sensor to calculate an amount of change in the acceleration over a certain period of time, acquiring an angular velocity per unit time about either a roll axis or a pitch axis of the vehicle from the angular velocity sensor, and determining an amount of change in the angular velocity in the certain period; When the amount of change in acceleration is equal to or greater than a first threshold and the amount of change in angular velocity is greater than a second threshold, the vehicle is identified as being in a first state, and when the amount of change in acceleration is smaller than the first threshold and the amount of change in angular velocity is equal to or less than a second threshold, the vehicle is identified as being in a second state different from the first state, and the identification result is output. It is , the amount of change in acceleration is obtained by integrating, for the certain period of time, a difference between the acceleration at a first time point and the acceleration at a second time point prior to the first time point, using the acceleration obtained for each unit time, The angular velocity change amount is obtained by integrating the difference between the acceleration at the first time point and the angular velocity at the second time point for the certain period of time using the angular velocity obtained for each unit time. A vehicle condition identification device. [2] An apparatus according to one aspect of the present disclosure, A device for identifying a state of a vehicle, comprising: A controller connected to the angular velocity sensor and the acceleration sensor, The controller: An acceleration per unit time in an axis corresponding to a longitudinal direction of the vehicle is acquired from the acceleration sensor, and a first difference is calculated as a difference between a current value and a previous value of the acceleration. acquiring an angular velocity per unit time about either a roll axis or a pitch axis of the vehicle from the angular velocity sensor, and calculating a second difference between a current value and a previous value of a sine direction vector about the roll axis or the pitch axis based on the angular velocity; The first difference of The second difference By dividing by Obtained It is a ratio The vehicle condition identification device identifies the vehicle as being in a first state when a state monitoring parameter is equal to or greater than a predetermined threshold, and identifies the vehicle as being in a second state different from the first state when the state monitoring parameter is smaller than the threshold, and outputs the identification result. [3] A method according to one embodiment of the present disclosure includes: 1. A method for identifying a state of a vehicle, the method being performed by a controller coupled to an angular velocity sensor and an acceleration sensor, the method comprising: acquiring an acceleration per unit time on an axis corresponding to a front-rear direction of the vehicle from the acceleration sensor, and calculating an amount of change in the acceleration over a certain period of time; acquiring an angular velocity per unit time about either a roll axis or a pitch axis of the vehicle from the angular velocity sensor, and determining an amount of change in the angular velocity in the certain period; identifying a state of the vehicle as a first state when the amount of change in acceleration is equal to or greater than a first threshold and the amount of change in angular velocity is greater than a second threshold, and identifying a state of the vehicle as a second state different from the first state when the amount of change in acceleration is smaller than the first threshold and the amount of change in angular velocity is equal to or less than a second threshold, and outputting the identification result; Including, the amount of change in acceleration is obtained by integrating, for the certain period of time, a difference between the acceleration at a first time point and the acceleration at a second time point prior to the first time point, using the acceleration obtained for each unit time, The angular velocity change amount is obtained by integrating the difference between the acceleration at the first time point and the angular velocity at the second time point for the certain period of time using the angular velocity obtained for each unit time. A vehicle state identification method. [4] A method according to one embodiment of the present disclosure includes: 1. A method for identifying a state of a vehicle, the method being performed by a controller coupled to an angular velocity sensor and an acceleration sensor, the method comprising: acquiring an acceleration per unit time on an axis corresponding to a longitudinal direction of the vehicle from the acceleration sensor, and calculating a first difference which is a difference between a current value and a previous value of the acceleration; acquiring an angular velocity per unit time about either a roll axis or a pitch axis of the vehicle from the angular velocity sensor, and calculating a second difference between a current value and a previous value of a sine direction vector about the roll axis or the pitch axis based on the angular velocity; The first difference of The second difference By dividing by Obtained It is a ratio identifying the vehicle as being in a first state when a state monitoring parameter is equal to or greater than a predetermined threshold, and identifying the vehicle as being in a second state different from the first state when the state monitoring parameter is smaller than the threshold, and outputting the identification result; The vehicle state identification method includes the steps of: [5] An apparatus according to one aspect of the present disclosure, A device for controlling the optical axis of a headlight provided on a vehicle, a first process is selected when the result of identifying the state of the vehicle obtained by the vehicle state identifying device according to [1] or [2] is the first state, and a second process different from the first process is selected when the result of identifying the state of the vehicle is the second state, to obtain an attitude angle of the vehicle, and to output a control signal for controlling the optical axis of the headlight using the attitude angle; An optical axis control device. [6] A method according to one embodiment of the present disclosure includes: A method for controlling a light axis of a headlight provided in a vehicle, comprising: Identifying the vehicle condition as described above in [3] or [4] direction a first process is selected when the result of identifying the state of the vehicle obtained by the method is the first state, and a second process different from the first process is selected when the result of identifying the state of the vehicle is the second state, to obtain an attitude angle of the vehicle, and a control signal for controlling the optical axis of the headlight is output using the attitude angle. This is an optical axis control method. [7] A system according to one embodiment of the present disclosure includes: The optical axis control device; a headlamp whose optical axis can be variably set based on the control signal output from the optical axis control device; A vehicle lighting system comprising:

[0006] According to the above configuration, the vehicle state can be identified with higher accuracy, and the optical axis control can be performed according to the vehicle state. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing a configuration of a vehicle lighting system according to an embodiment. [Diagram 2] FIG. 2 is a diagram showing an example of the configuration of a computer that realizes a controller of the vehicle lighting system. [Diagram 3] FIG. 3 is a diagram showing an example of a state transition of a vehicle and the accompanying changes in acceleration, roll angular velocity, and vehicle speed. [Figure 4] FIG. 4 is a table showing the relationship between the characteristics of the changes in the X-axis acceleration and the roll angular velocity and the vehicle state. [Diagram 5] FIG. 5 is a flowchart showing a process for generating parameters used to identify the vehicle state based on data output from the gyro sensor and the acceleration sensor. [Figure 6] FIG. 6 is a flowchart showing a procedure for identifying the vehicle state in the controller and controlling the light axis using the state. [Figure 7] FIG. 7 is a diagram for explaining vector quantities used for the unique parameters. [Figure 8] FIG. 8 is a flowchart showing a process for generating parameters used to identify the vehicle state based on data output from the gyro sensor and the acceleration sensor. [Figure 9] FIG. 9 is a flowchart showing a procedure for identifying the vehicle state in the controller and controlling the light axis using the state. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] (First embodiment) 1 is a diagram showing the configuration of a vehicle lighting system according to the first embodiment. This vehicle lighting system irradiates light by variably setting the optical axis according to the attitude of the vehicle itself, and is configured to include a controller 10, a gyro sensor 11, an acceleration sensor 12, and a pair of lamp units 30L and 30R.

[0009] The controller 10 is for controlling the operation of the vehicle lighting system, and is configured, for example, using a computer capable of executing a predetermined operation program. Here, the functions realized by the controller 10 will be described using functional blocks to facilitate understanding. The controller 10 has a vibration detection unit 21, a running / stopping detection unit 22, a vehicle state output unit 23, and a light axis control unit 24. In addition, a signal or data indicating the vehicle speed of the vehicle is input to the controller 10. The vehicle speed is detected by a sensor (not shown) or the like provided on the vehicle, and is obtained in the form of, for example, a vehicle speed pulse signal or vehicle speed data.

[0010] The vibration detection unit 21, the running / stopping detection unit 22, and the vehicle state output unit 23 of the controller 10 constitute a "vehicle state identification device" according to the present disclosure, and the "vehicle state characteristic method" is executed. The vibration detection unit 21, the running / stopping detection unit 22, the vehicle state output unit 23, and the optical axis control unit 24 of the controller 10 constitute a "optical axis control device" according to the present disclosure, and the "optical axis control method" is executed.

[0011] The gyro sensor 11 is a sensor (angular velocity sensor) that detects an angular velocity and outputs data or a signal according to the magnitude of the angular velocity. The gyro sensor 11 of this embodiment is only required to detect an angular velocity corresponding to at least either a roll angle or a pitch angle of the vehicle. For example, the gyro sensor 11 of this embodiment is capable of detecting angular velocities corresponding to both a roll angle and a pitch angle. The gyro sensor 11 is installed at a predetermined position of the vehicle (for example, the back side of a glove box, etc.).

[0012] The acceleration sensor 12 is a sensor that detects acceleration and outputs data or a signal according to the magnitude of the acceleration. The acceleration sensor 12 of this embodiment is capable of detecting at least the acceleration corresponding to each of the longitudinal direction and the vertical direction of the vehicle. Note that each axis of the acceleration sensor 12 does not necessarily have to completely coincide with each of the longitudinal direction and the vertical direction of the vehicle, and in that case, a correction process may be performed on the detected value as appropriate.

[0013] The vibration detection unit 21 detects vehicle vibrations based on data (or signals; the same applies below) output from the gyro sensor 11 or acceleration sensor 12, and outputs data (or signals; the same applies below) according to the magnitude of the vibrations. Specifically, the vibration detection unit 21 generates and outputs data corresponding to either "driving", "parked (stable)", or "uncertain". "Uncertain" here refers to a state corresponding to either "driving" or "parked (unstable)".

[0014] When data corresponding to "uncertain" is generated from the vibration detection unit 21, the running / stopping detection unit 22 further uses parameters obtained based on the data output from each of the gyro sensor 11 and the acceleration sensor 12, and generates data corresponding to "running" or data (or signal; the same applies below) corresponding to "stopped (unstable)" depending on the parameters.

[0015] The vehicle state output unit 23 determines the vehicle state based on the data of the detection results of the vibration detection unit 21 and the running / stopping detection unit 22, and supplies data (or a signal; the same applies below) indicating the vehicle state to the optical axis control unit 24. In this embodiment, the vehicle state output unit 23 uses at least one of three states, "running", "stopped (stable)", and "stopped (unstable)", as the vehicle state.

[0016] The optical axis control unit 24 obtains the vehicle attitude angle (angle between the road surface and the vehicle longitudinal axis) based on the acceleration detected by the acceleration sensor 12, generates a control signal for controlling the optical axis of the light emitted by each lamp unit 30L, 30R according to this attitude angle, and supplies (outputs) it to each lamp unit 30L, 30R. At this time, the optical axis control unit 24 appropriately selects a calculation method according to the vehicle state output from the vehicle state output unit 23, and obtains the vehicle attitude angle by applying the selected calculation method. Specifically, different calculation methods are used when the vehicle state is "driving" and when the vehicle state is "parked (stable)". A publicly known method can be used as the calculation method for each. Also, when the vehicle state is "parked (unstable)", the process of obtaining the attitude angle is temporarily halted, and the optical axis control is stopped.

[0017] Each headlamp 30L, 30R is provided on the left and right sides of the front of the vehicle, and is for irradiating light ahead of the vehicle. As each lamp unit 30L, 30R, various known lamp units can be adopted. For example, a lamp unit that has a light source unit including a light source and a reflector, and an actuator that adjusts the direction of the light source unit up and down to adjust the optical axis (main traveling direction) of the light emitted from the light source unit up and down in the pitch direction of the vehicle, and can mechanically control the light irradiation range can be used. In addition, a lamp unit that can electronically control the light irradiation range can be used, such as a lamp unit that can control the light irradiation range by combining a light source and a liquid crystal element, a lamp unit that can control the light irradiation range by selectively turning on / off multiple LEDs, and a lamp unit that can control the light irradiation range by scanning the light from a laser element with a movable reflector and turning on and off the laser element at high speed at that time.

[0018] FIG. 2 is a diagram showing an example of the configuration of a computer that realizes a controller of a vehicle lighting system. The computer shown in the figure includes a central processing unit (CPU) 201, a read only memory (ROM) 202, a random access memory (RAM) 203, a storage device 204, and an external interface (I / F) 205, all of which are communicably connected to one another. The CPU 201 operates based on a basic control program read from the ROM 202, and realizes the functions of the controller 10 described above by reading and executing a program (application program) 206 stored in the storage device 204. The RAM 203 temporarily stores data to be used during the operation of the CPU 201. The storage device 204 is a non-volatile storage device such as a hard disk or a solid state drive, and stores various data such as the program 206. The external interface 205 is an interface that connects the CPU 201 to an external device.

[0019] FIG. 3 is a diagram showing an example of a vehicle state transition and the accompanying changes in acceleration, roll angular velocity, and vehicle speed. FIG. 4 is a diagram showing a table summarizing the relationship between the characteristics of changes in X-axis acceleration and roll angular velocity and the vehicle state. Here, the X-axis acceleration is the acceleration of an axis corresponding to the front-rear direction of the vehicle (hereinafter referred to as the "X-axis"). The roll angular velocity is the angular velocity corresponding to the roll angle of the vehicle (the rotation angle around the X-axis). In this embodiment, the vehicle state is identified by utilizing the characteristics of changes in the X-axis acceleration and roll angular velocity shown here.

[0020] Specifically, when a load is placed on the vehicle, the X-axis acceleration changes and the roll angular velocity also changes (event (1) in the figure). The vehicle state at this time corresponds to "stopped (unstable)." When the vehicle state is "stable stopped," there is almost no change in either the X-axis acceleration or the roll angular velocity (event (2) in the figure).

[0021] When accelerating (or decelerating) gradually, the X-axis acceleration changes gradually, but the roll angular velocity remains almost unchanged and is around 0 dps (event (3) in the diagram). Also, when accelerating, the X-axis acceleration changes greatly and the roll angular velocity also changes (event (4) in the diagram).

[0022] When driving at a constant speed, the X-axis acceleration does not change, for example maintaining the value at the start of driving, and the roll angular velocity remains almost unchanged at around 0 dps (event (5) in the figure). The vehicle state at this time corresponds to "driving (accelerating)". Also, when decelerating, the X-axis acceleration changes significantly and the roll angular velocity also changes (event (6) in the figure). The vehicle state at this time corresponds to "driving (decelerating)".

[0023] Also, just before deceleration is completed, the X-axis acceleration and roll angular velocity also change (event (7) in the figure). The vehicle state at this time corresponds to "stopped (unstable)." When deceleration is completed and the vehicle vibration has settled, there is almost no change in either the X-axis acceleration or the roll angular velocity (event (8) in the figure). The vehicle state at this time corresponds to "stable stopped."

[0024] 5 is a flowchart showing a process for generating parameters used to identify the vehicle state based on data output from the gyro sensor and the acceleration sensor. These processes are repeatedly executed by the running / stopping detection unit 22 of the controller 10. In any of the operation procedures, the order of the processes can be appropriately changed as long as no contradiction or inconsistency occurs in the results of the information processing. In addition, other processes not mentioned here may be added, and such implementations are not excluded.

[0025] Specifically, the running / stopping detection unit 22 acquires roll angular velocity data from the gyro sensor 11 (step S1), and acquires X-axis acceleration data from the acceleration sensor 12 (step S2). For example, in this embodiment, the roll angular velocity data and the X-axis acceleration data are each acquired every 100 ms.

[0026] Using each of the acquired data, the running / stopping detection unit 22 calculates the amount of change in the X-axis acceleration per second, ΔX 1s (Step S3) The change in the X-axis acceleration per second, ΔX 1s is obtained by using the X-axis acceleration obtained every 100 ms and integrating the difference X(n)-X(n-1) between the X-axis acceleration value X(n) at a certain time and the X-axis acceleration value X(n-1) at the time just before that for, for example, one second. Specifically, it is expressed by the following formula. ΔX 1s =ΣX(n)-X(n-1)

[0027] The running / stopping detection unit 22 also calculates the amount of change Gx_A(n) in the roll angle per second (step S4). The amount of change Gx_A(n) in the roll angle per second is obtained by using the roll angular velocity obtained every 100 ms and integrating the difference θgx(n)-θgx(n-1) between the roll angular velocity θgx(n) at a certain time and the value θgx(n-1) of the roll angular velocity at the time immediately before that, for example, for one second. Specifically, it is expressed by the following formula. Gx_A(n) = Σθgx(n) - θgx(n-1)

[0028] Each parameter (ΔX 1s and Gx_A(n)) can be used to identify the vehicle state as shown below.

[0029] 6 is a flowchart showing the process of identifying the vehicle state in the controller and controlling the light axis using the state. The process shown here is repeatedly executed, for example, every 100 ms. In any of the operation procedures, the order of the processes can be changed as appropriate as long as no contradiction or inconsistency occurs in the results of the information processing. In addition, other processes not mentioned here may be added, and such implementations are not excluded.

[0030] When the X-axis acceleration detected by the acceleration sensor 12 exceeds 10 mG for 0.5 seconds or more (step S11; YES), the vibration detection unit 21 of the controller 10 generates data corresponding to "driving". In this case, the vehicle state output unit 23 determines the vehicle state to be "driving" and outputs data indicating that to the optical axis control unit 24 (step S12). Note that for vibration detection in this step, the roll angular velocity may be used instead of the X-axis acceleration, or both may be used.

[0031] On the other hand, when the state where the X-axis acceleration exceeds 10 mG does not continue for 0.5 seconds or more (step S11; NO), and when the state where the X-axis acceleration is 10 mG or less continues for 2.0 seconds or more (step S13; YES), the vibration detection unit 21 of the controller 10 generates data corresponding to "parked (stable)". In this case, the vehicle state output unit 23 determines the vehicle state to be "parked (stable)" and outputs data indicating that to the optical axis control unit 24 (step S14).

[0032] On the other hand, if the state where the X-axis acceleration is not 10 mG or less continues for 2.0 seconds or more (step S13; NO), the vibration detection unit 21 of the controller 10 generates data corresponding to "uncertain." Here, "uncertain" indicates a state corresponding to either "driving" or "parked (unstable)."

[0033] In this case, the running / stopping detection unit 22 calculates ΔX 1s If Gx_A(n) is ≧10mG or Gx_A(n)>0.2dps (step S15; YES), data corresponding to "parked (unstable)" is generated. In this case, the vehicle state output unit 23 determines the vehicle state to be "parked (unstable)" and outputs data indicating that to the optical axis control unit 24 (step S16).

[0034] In addition, the running / stopping detection unit 22 calculates ΔX 1s < 10mG or Gx_A(n) ≦ 0.2dps (step S15; NO), 10mG > ΔX 1s If Gx_A(n) is greater than or equal to 5 mg and Gx_A(n) is less than or equal to 0.2 dps, data corresponding to "driving" is generated (step S17; YES). In this case, the vehicle state output unit 23 determines the vehicle state to be "driving" and outputs data indicating that to the optical axis control unit 24 (step S18).

[0035] In addition, the running / stopping detection unit 22 is 10mG>ΔX 1s If any one of the conditions Gx_A(n) > 5 mg or Gx_A(n) ≦ 0.1 dps is not satisfied (step S17; NO), data corresponding to "parked (unstable)" is generated. In this case, the vehicle state output unit 23 determines the vehicle state to be "parked (unstable)" and outputs data indicating that to the optical axis control unit 24 (step S19).

[0036] When the vehicle state is output from the vehicle state output unit 23, the optical axis control unit 24 calculates the attitude angle of the vehicle according to the vehicle state, generates a control signal for controlling the optical axis of the light emitted by each lamp unit 30L, 30R according to this attitude angle, and outputs the control signal to each lamp unit 30L, 30R, or stops outputting the control signal (step S20).

[0037] In the above embodiment, the roll angle may be replaced with a pitch angle. Here, the pitch angle is a rotation angle around the left-right axis of the vehicle. Specifically, the process in step S4 of FIG. 5 is replaced with a calculation of the pitch angle change amount Gy_A(n) per second. The pitch angle change amount Gy_A(n) per second is obtained by using a pitch angular velocity obtained every 100 ms and integrating the difference θgy(n)-θgy(n-1) between the pitch angular velocity θgy(n) at a certain time and the pitch angular velocity θgy(n-1) at the time immediately before that, for a period equivalent to, for example, one second. Specifically, it is expressed by the following formula. Gy_A(n) = Σθgy(n) - θgy(n-1)

[0038] In addition, in steps S15 and S17 in FIG. 6, the part using Gx_A(n) is replaced with Gy_A(n). Specifically, in step S15, ΔX 1s If ΔX is greater than or equal to 10 mG or Gy_A(n)>0.1 dps (step S15; YES), data corresponding to "stopped (unstable)" is generated. 1s <10mG, or Gy_A(n)≦0.1dps (step S15; NO), and 10mG>ΔX 1s If Gy_A(n) is greater than 5 mg and Gy_A(n) is less than or equal to 0.1 dps, data corresponding to "driving" is generated (step S17; YES).

[0039] According to the first embodiment and its modified examples described above, the vehicle state can be identified with higher accuracy, and the optical axis control can be performed according to the identified vehicle state.

[0040] In detail, since the inclination of the vehicle is small during extremely low-speed running, it is considered difficult to detect the change when only the angular velocity detected by the gyro sensor is used. Also, when only the acceleration detected by the acceleration sensor is used, it is considered difficult to distinguish between the change in the vehicle's attitude due to the load and the change in the vehicle's attitude due to acceleration / deceleration, especially when trying to shorten the detection time. Furthermore, when the open / closed state of the doors, etc. is used, even if the stopped state can be grasped, other states cannot be distinguished, and it is not possible to respond when a signal indicating the open / closed state is not obtained, and it is considered difficult to respond to a vehicle having a cargo bed. According to the first embodiment, etc., these inconveniences can be eliminated. The same applies to the second embodiment, etc. described later, and other modified examples.

[0041] In the first embodiment and its modified examples, the numerical values ​​used as the criteria for case classification are merely examples and are not limited to these. It is desirable to set appropriate numerical values ​​through experiments depending on the vehicle model and other conditions. For example, ΔX 1s Regarding 10mG>ΔX 1s Although a numerical example of >5mG has been given, the lower limit of 5mG may be set appropriately taking into consideration the noise of the acceleration sensor 12 itself, and the upper limit of 10mG may be set appropriately to a numerical value lower than the numerical value corresponding to vibrations due to loading of luggage, etc. Also, Gx_A(n) and Gy_A(n) may be set appropriately to numerical values ​​lower than the numerical value corresponding to vibrations due to loading of luggage, etc.

[0042] Second embodiment In the first embodiment described above, the vehicle state is classified by comparing the change amount of the angular velocity of the roll angle (or pitch angle) and the X-axis acceleration with a predetermined reference value, but the vehicle state can also be classified by using a unique parameter described below. Note that the configuration of the vehicle lighting system is the same as that of the first embodiment, and only the content of the information processing by the running / stopping detection unit 22 is different, so only the differences will be described in detail below.

[0043] 7 is a diagram for explaining vector quantities used in the unique parameters. Here, the vehicle is shown as viewed from the front side. As shown in the figure, if the angular velocity per unit time of the roll angle θg, which is the angle around the X-axis (vehicle longitudinal axis) of the vehicle, is expressed as a vector quantity, the sine direction vector Gy_Vx(n) of the roll angle can be expressed as follows: Gy_Vx(n)=-9.8sin(θg)

[0044] The X-axis acceleration obtained from the acceleration sensor 12 is represented as GA_x, its current value is represented as GA_x(n), and the immediately preceding value is represented as GA_x(n-1).

[0045] Here, n is the unit time, and indicates that the calculation is performed every 100 ms. For example, for Gy_Vx(n), Gy_Vx(n-1) is the value obtained 100 ms ago. Similarly, for GA_x(n), GA_x(n-1) is the value obtained 100 ms ago.

[0046] In this case, the state monitoring parameter Sc is defined as follows: Sc=(Gy_Vx(n)-Gy_Vx(n-1)) / (GA_x(n)-GA_x(n-1))

[0047] This state monitoring parameter Sc indicates the ratio of the change in the sine vector of the roll angle to the change in the X-axis acceleration. This state monitoring parameter is a parameter that more strongly reflects the characteristics of the X-axis acceleration and the roll angular velocity as shown in FIG. 4 above. Specifically, when the vehicle is stopped and the attitude angle of the vehicle changes, the change in the roll angular velocity and the change in the X-axis acceleration change in the same manner, while when the attitude angle of the vehicle does not change, neither of them changes. In addition, since the roll angular velocity hardly changes during low-speed driving, the value of the sine vector calculated does not change much. In contrast, the X-axis acceleration changes even during low-speed driving. This is because, even during low-speed driving, the vehicle cannot maintain driving by inertia alone, so some acceleration or deceleration occurs, and the vehicle rarely drives at a constant speed.

[0048] From the above, when the state monitoring parameter Sc is defined as above, since the roll angular velocity is used as the numerator and the X-axis acceleration is used as the denominator, the value of Sc becomes very small while the vehicle is moving and at a low speed. On the other hand, since the roll angular velocity and the X-axis acceleration fluctuate in the same way while the vehicle is stopped, the value of Sc becomes relatively large. In other words, it can be used as a parameter that clearly indicates the characteristics of the vehicle state. In addition, since the state monitoring parameter can be obtained at relatively short intervals, for example, every 100 ms, the time required to identify the vehicle state can be further shortened.

[0049] 8 is a flowchart showing a process for generating parameters used to identify the vehicle state based on data output from the gyro sensor and the acceleration sensor. These processes are repeatedly executed by the running / stopping detection unit 22 of the controller 10. In any of the operation procedures, the order of the processes can be appropriately changed as long as no contradiction or inconsistency occurs in the results of the information processing. In addition, other processes not mentioned here may be added, and such implementations are not excluded.

[0050] Specifically, the running / stopping detection unit 22 acquires roll angular velocity data from the gyro sensor 11 (step S31) and acquires X-axis acceleration data from the acceleration sensor 12 (step S32). For example, in this embodiment, the roll angular velocity data and the X-axis acceleration data are each acquired every 100 ms.

[0051] Using each of the acquired data, the running / stopping detection unit 22 calculates a sine direction vector Gy_Vx(n) of the roll angle (step S33). Then, the running / stopping detection unit 22 calculates a state monitoring parameter Sc (step S34).

[0052] Thereafter, the running / stopping detection unit 22 temporarily stores GA_x(n) and Gy_Vx(n) in a memory. The GA_x(n) and Gy_Vx(n) stored here are used as Gy_Vx(n-1) in the next calculation. Note that, when the previous values ​​GA_x(n) and Gy_Vx(n) are not present in the first calculation, the running / stopping detection unit 22 may perform the calculations of steps S34 and S35 by a commonly used method, for example, by using a predetermined initial value.

[0053] 9 is a flowchart showing the process of identifying the vehicle state in the controller and controlling the light axis using the state. The process shown here is repeatedly executed, for example, every 100 ms. In any of the operation procedures, the order of the processes can be changed as appropriate as long as no contradiction or inconsistency occurs in the results of the information processing. In addition, other processes not mentioned here can be added, and such implementations are not excluded.

[0054] Steps S41 to S44 are similar to steps S11 to S14 in the flowchart of the first embodiment described above, and therefore a description thereof will be omitted here.

[0055] When the state monitoring parameter Sc is greater than 0.5 (step S45; YES), the running / stopping detection unit 22 generates data corresponding to "stopped (unstable)". In this case, the vehicle state output unit 23 determines the vehicle state to be "stopped (unstable)" and outputs data indicating that to the optical axis control unit 24 (step S46).

[0056] Furthermore, when the state monitoring parameter Sc is equal to or less than 0.5 (step S45; NO), the running / stopping detection unit 22 generates data corresponding to "running". In this case, the vehicle state output unit 23 determines the vehicle state to be "running" and outputs data indicating that to the optical axis control unit 24 (step S47).

[0057] When the vehicle state is output from the vehicle state output unit 23, the optical axis control unit 24 calculates the attitude angle of the vehicle according to the vehicle state, and generates a control signal for controlling the optical axis of the light emitted by each lamp unit 30L, 30R according to this attitude angle, and outputs the signal to each lamp unit 30L, 30R, or stops outputting the control signal (step S48).

[0058] In the above embodiment, the roll angle can be replaced with the pitch angle. Specifically, the process in step S33 in FIG. 8 is replaced with the calculation of the sine vector Gy_Vy(n) of the pitch angle. Gy_Vy(n) is expressed as follows. Here, θg is the pitch angle, which is the angle around the Y axis of the vehicle (the axis in the left-right direction of the vehicle). Gy_Vy(n)=-9.8sin(θg)

[0059] In step S34 of FIG. 8, the state monitoring parameter Sc is defined as follows. Sc=(Gy_Vy(n)-Gy_Vy(n-1)) / (GA_x(n)-GA_x(n-1)) Then, in step S47 of FIG. 9, for example, if Sc is greater than 1.0, the process proceeds to step S46, and if Sc is 1.0 or less, the process proceeds to step S47.

[0060] According to the second embodiment and its modified examples described above, the vehicle state can be identified with higher accuracy, and the optical axis control can be performed according to the identified vehicle state.

[0061] In addition, the numerical values ​​used as the criteria for distinguishing between cases in the second embodiment and its modified examples are merely examples and are not limited to these, and it is desirable to set appropriate numerical values ​​through experiments etc. depending on the vehicle model and other conditions.

[0062] (Other modified embodiments) The present disclosure is not limited to the contents of the above-described embodiments, and can be modified and implemented in various ways within the scope of the gist of the present disclosure. For example, the above-described embodiments have been described using a four-wheel vehicle as an example, but the present disclosure can be applied to two-wheel vehicles, three-wheel vehicles, and various other vehicles. In a four-wheel vehicle, the vehicle tends to tilt in the left-right direction when a passenger gets on or off the vehicle or when luggage is loaded, so it is considered that the embodiment using the roll angular velocity or its modified embodiment is more preferably used. On the other hand, for example, in a two-wheel vehicle, the vehicle tends to tilt in the front-rear direction, so it is considered that the embodiment using the pitch angular velocity or its modified embodiment is more preferably used in many situations. However, there is no particular limit to which embodiment is applied, as it depends on the vehicle situation, etc.

[0063] In addition, in the above-described embodiment, the vehicle condition identification device and method according to the present disclosure are used for adjusting the optical axis of a vehicle lamp, but the scope of application of the device and method is not limited thereto. For example, the device and method may be applied to a situation where control is performed according to the vehicle condition in a car navigation system, or to a situation where automatic driving control of a vehicle is performed. [Explanation of symbols]

[0064] 10: controller, 11: gyro sensor, 12: acceleration sensor, 21: vibration detection unit, 22: running / stopping detection unit, 23: vehicle state output unit, 24: optical axis control unit, 30L, 30R: lamp unit

Claims

1. A device for identifying a state of a vehicle, comprising: A controller connected to the angular velocity sensor and the acceleration sensor, The controller: An acceleration per unit time on an axis corresponding to a front-rear direction of the vehicle is acquired from the acceleration sensor to calculate an amount of change in the acceleration over a certain period of time, acquiring an angular velocity per unit time about either a roll axis or a pitch axis of the vehicle from the angular velocity sensor, and determining an amount of change in the angular velocity in the certain period; when the amount of change in acceleration is equal to or greater than a first threshold and the amount of change in angular velocity is greater than a second threshold, the vehicle is identified as being in a first state, and when the amount of change in acceleration is smaller than the first threshold and the amount of change in angular velocity is equal to or less than a second threshold, the vehicle is identified as being in a second state different from the first state, and the identification result is output; the amount of change in acceleration is obtained by integrating, for the certain period of time, a difference between the acceleration at a first time point and the acceleration at a second time point prior to the first time point, using the acceleration obtained for each unit time, The angular velocity change amount is obtained by integrating the difference between the acceleration at the first time point and the angular velocity at the second time point for the certain period of time using the angular velocity obtained for each unit time. Vehicle condition identification device.

2. The controller: identifying the vehicle as being in the second state when the amount of change in acceleration is smaller than the first threshold value and larger than a third threshold value, and the amount of change in angular velocity is equal to or smaller than the second threshold value; The vehicle condition identification device according to claim 1.

3. The controller, when a state in which the acceleration exceeds the first threshold value has not continued for a first period or more that is shorter than the certain period, and a state in which the acceleration is equal to or less than the first threshold value has not continued for a second period or more that is longer than the certain period, the acceleration change amount and the angular velocity change amount are used to determine whether the vehicle is in the first state or the second state. The vehicle condition identification device according to claim 1 or 2.

4. A device for identifying a state of a vehicle, comprising: A controller connected to the angular velocity sensor and the acceleration sensor, The controller: An acceleration per unit time in an axis corresponding to a longitudinal direction of the vehicle is acquired from the acceleration sensor, and a first difference is calculated as a difference between a current value and a previous value of the acceleration. acquiring an angular velocity per unit time about either a roll axis or a pitch axis of the vehicle from the angular velocity sensor, and calculating a second difference between a current value and a previous value of a sine direction vector about the roll axis or the pitch axis based on the angular velocity; identifying the vehicle as being in a first state when a state monitoring parameter, which is a ratio obtained by dividing the first difference by the second difference, is equal to or greater than a predetermined threshold, and identifying the vehicle as being in a second state different from the first state when the state monitoring parameter is smaller than the threshold, and outputting the identification result. Vehicle condition identification device.

5. The sine direction vector is expressed as −9.8×sin(θg), and can be obtained by substituting the angular velocity per unit time into θg. The vehicle condition identifying device according to claim 4.

6. The first state corresponds to a state in which the vehicle is moving, and the second state corresponds to a state in which the vehicle is stopped and has vibrations. The vehicle state specifying device according to any one of claims 1 to 5.

7. 1. A method for identifying a state of a vehicle, the method being performed by a controller coupled to an angular velocity sensor and an acceleration sensor, the method comprising: acquiring an acceleration per unit time on an axis corresponding to a longitudinal direction of the vehicle from the acceleration sensor, and determining an amount of change in the acceleration over a certain period of time; acquiring an angular velocity per unit time about either a roll axis or a pitch axis of the vehicle from the angular velocity sensor, and determining an amount of change in the angular velocity in the certain period; identifying a state of the vehicle as a first state when the amount of change in acceleration is equal to or greater than a first threshold value and the amount of change in angular velocity is greater than a second threshold value, and identifying a state of the vehicle as a second state different from the first state when the amount of change in acceleration is smaller than the first threshold value and the amount of change in angular velocity is equal to or less than a second threshold value, and outputting the identification result; Including, the amount of change in acceleration is obtained by integrating, for the certain period of time, a difference between the acceleration at a first time point and the acceleration at a second time point prior to the first time point, using the acceleration obtained for each unit time, The angular velocity change amount is obtained by integrating the difference between the acceleration at the first time point and the angular velocity at the second time point for the certain period of time using the angular velocity obtained for each unit time. Method for identifying vehicle condition.

8. 1. A method for identifying a state of a vehicle, the method being performed by a controller coupled to an angular velocity sensor and an acceleration sensor, the method comprising: acquiring an acceleration per unit time on an axis corresponding to a longitudinal direction of the vehicle from the acceleration sensor, and calculating a first difference which is a difference between a current value and a previous value of the acceleration; acquiring an angular velocity per unit time about either a roll axis or a pitch axis of the vehicle from the angular velocity sensor, and calculating a second difference between a current value and a previous value of a sine direction vector about the roll axis or the pitch axis based on the angular velocity; identifying the vehicle as being in a first state when a state monitoring parameter, which is a ratio obtained by dividing the first difference by the second difference, is equal to or greater than a predetermined threshold, and identifying the vehicle as being in a second state different from the first state when the state monitoring parameter is smaller than the threshold, and outputting the identification result; A vehicle state identification method comprising:

9. A device for controlling the optical axis of a headlight provided on a vehicle, When the result of identifying the state of the vehicle obtained by the vehicle state identifying device according to any one of claims 1 to 6 is the first state, a first process is selected, and when the result of identifying the state of the vehicle obtained by the vehicle state identifying device according to any one of claims 1 to 6 is the second state, a second process different from the first process is selected to obtain an attitude angle of the vehicle, and a control signal for controlling the optical axis of the headlights is output using the attitude angle. Optical axis control device.

10. A method for controlling a light axis of a headlight provided in a vehicle, comprising: a control signal for controlling the optical axis of the headlights by using the attitude angle of the vehicle is outputted, the control signal being outputted when the vehicle state is determined to be the first state and the vehicle state is determined to be the second state and the vehicle state is determined to be the first state and the vehicle state is determined to be the second state ... and the vehicle state is determined to be the first state and the vehicle state is determined to be the second state and the vehicle state is determined to be the Optical axis control method.

11. The optical axis control device according to claim 9 , a headlamp whose optical axis can be variably set based on the control signal output from the optical axis control device; A vehicle lighting system comprising:

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