An adaptive headlamp system and control method based on motion posture perception

Abstract

The present invention discloses an adaptive headlamp system and control method based on motion posture perception. The adaptive headlamp system includes: a six-axis motion sensor, which is used to collect longitudinal acceleration, lateral acceleration, vertical acceleration, pitch angular velocity and yaw angular velocity of a vehicle body; a main controller, which is electrically connected to the six-axis motion sensor, receives information collected by the six-axis motion sensor, and calculates headlamp control information based on the received information; a left headlamp dimming drive mechanism, which is electrically connected to the main controller, and adjusts the pitch angle and horizontal rotation angle of the left headlamp according to the headlamp control information; and a right headlamp dimming drive mechanism, which is electrically connected to the main controller, and adjusts the pitch angle and horizontal rotation angle of the right headlamp according to the headlamp control information.

Description

Technical Field

[0001] The present invention belongs to the technical field of automobile headlamp control, and in particular relates to an adaptive headlamp system and a control method based on motion posture perception. Background Art

[0002] Ensuring lighting during nighttime driving is crucial for driving safety. Adaptive headlighting technology automatically calculates the headlight angle based on the vehicle's posture and automatically compensates for the vehicle's lighting area to maintain a relatively stable driver's field of view during nighttime driving. Existing adaptive headlighting systems have the following main drawbacks:

[0003] The vehicle's posture requires the joint determination of multiple sensors. The use of discrete sensors and additional wiring harnesses increases system complexity, vehicle weight and cost. At the same time, the functional integration of the headlight control system will also be affected. Summary of the Invention

[0004] One of the purposes of the present invention is to provide an adaptive headlight system based on motion posture perception, which only requires a six-axis motion sensor as a signal acquisition device, without the need for additional discrete sensors, can save the configuration of additional wiring harnesses, can effectively reduce system complexity, and effectively reduce the total vehicle body volume.

[0005] The present invention also provides a control method for an adaptive headlight system based on motion posture perception, which can adaptively adjust the vehicle headlights according to the information obtained by the six-axis motion sensor to maintain the relative stability of the driver's field of view when driving at night.

[0006] Another purpose of the present invention is to adjust the illumination angle of the headlight according to the vehicle speed, so that the driver can have a better sight distance, predict the road conditions in advance, and avoid danger in advance.

[0007] The technical solution provided by the present invention is:

[0008] An adaptive headlight system based on motion posture perception, comprising:

[0009] A six-axis motion sensor, which is used to collect the longitudinal acceleration, lateral acceleration, vertical acceleration, pitch angular velocity, and yaw angular velocity of the vehicle body;

[0010] a main controller electrically connected to the six-axis motion sensor, receiving information collected by the six-axis motion sensor, and calculating headlamp control information based on the received information;

[0011] a left headlamp dimming drive mechanism, electrically connected to the main controller, for adjusting the pitch angle and horizontal rotation angle of the left headlamp according to the headlamp control information;

[0012] The right headlamp dimming drive mechanism is electrically connected to the main controller and adjusts the pitch angle and horizontal rotation angle of the right headlamp according to the headlamp control information.

[0013] A control method for an adaptive headlight system based on motion posture perception, comprising:

[0014] The longitudinal acceleration of the vehicle body is collected by a six-axis motion sensor x , lateral acceleration a y , vertical acceleration a z , pitch angular velocity ω θ and yaw rate

[0015] When the vehicle is moving straight and its pitch attitude changes, the pitch angles of the left and right headlights at time t are controlled as follows:

[0016]

[0017] in:

[0018]

[0019] Where H a0 is the initial height of the six-axis motion sensor from the ground; d z (t-τ) is the vertical displacement of the vehicle at time (t-τ); τ is the sensor sampling interval; v z (t) is the vertical velocity of the vehicle at time t, v z (t-τ) is the vertical velocity of the vehicle at the moment (t-τ); H f L is the vertical distance between the center of the headlight and the six-axis motion sensor; f is the horizontal distance between the center of the headlight and the six-axis motion sensor; α θ (t-τ) is the pitch angle of the vehicle at time (t-τ); ω θ (t) is the pitch angular velocity of the vehicle at time t, ω θ (t-τ) is the pitch angular velocity of the vehicle at time (t-τ).

[0020] Preferably, the control method of the adaptive headlight system based on motion posture perception further includes:

[0021] The longitudinal speed v at time t x (t) is compared with the angle compensation speed threshold v0. When v x When (t)≥v0, the pitch angles of the left and right headlights of the vehicle at time t are controlled as follows:

[0022]

[0023] Among them, θ max is the maximum illumination angle of the car headlight, v max is θ max The upper speed limit for the vehicle to achieve the maximum lighting distance is θ0, which is the initial aiming angle of the headlight.

[0024] Preferably, during the process of adjusting the pitch angle of the headlight, the single adjustment amplitude is limited, and the pitch angles of the left and right headlights of the vehicle after a single adjustment are controlled to be:

[0025]

[0026] Among them, θ c (t) is the current headlight angle; Δθ st is the maximum amplitude of angle adjustment, θ P (t) is the target adjustment value of the vehicle headlight pitch angle.

[0027] Preferably, the control method of the adaptive headlight system based on motion posture perception further includes:

[0028] When the vehicle passes through a bumpy road, the left and right headlights of the vehicle are controlled to maintain the current pitch angle.

[0029] Preferably, the method for judging the bumpy road surface is:

[0030] Calculate the weighted mean absolute error (MAE) of the vehicle's longitudinal and vertical accelerations a (t) and the weighted mean absolute error (MAE) of the vehicle's longitudinal and vertical acceleration slopes s (t);

[0031] If MAE a (t)>TH MAEa And MAE s (t)>TH MAEs

[0032] Among them, TH MAEa is the threshold value of the mean absolute error of acceleration, TH MAEs is the discrimination threshold of the mean absolute error of the acceleration slope.

[0033] Preferably, the control method of the adaptive headlight system based on motion posture perception further includes:

[0034] When the vehicle yaw angle When the horizontal angles of the left and right headlights of the vehicle are adjusted:

[0035] When the vehicle yaw angle When , the horizontal turning angles of the left and right headlights of the vehicle are controlled as follows:

[0036]

[0037] When the vehicle yaw angle When , the horizontal turning angles of the left and right headlights of the vehicle are controlled as follows:

[0038]

[0039] in, is the vehicle yaw angle at time t, is the vehicle yaw angle at time (t-τ), is the proportional coefficient of the angle compensation, is the horizontal angle compensation threshold, is the vehicle yaw angular velocity at time t, is the vehicle yaw rate at time (t-τ).

[0040] Preferably, during the adjustment of the horizontal angles of the left and right headlights of the vehicle, if Then the horizontal turning angles of the left and right headlights of the vehicle are restored to:

[0041]

[0042] in, is the vehicle yaw rate threshold, which is a positive value close to zero.

[0043] Preferably, The value range is 10°~20°.

[0044] The beneficial effects of the present invention are:

[0045] The adaptive headlamp system based on motion posture perception provided by the present invention does not require the installation of multiple sensors. It only uses the acceleration and angular velocity information of each axis provided by the integrated motion sensor chip to calculate the vehicle posture in real time, and obtains the illumination angle adjustment value of the headlamp, thereby realizing the adaptive leveling and automatic corner compensation functions of the headlamp; the motion sensor chip can be highly integrated with the headlamp controller, and there is no need for additional discrete axle height sensors and other devices to provide information such as suspension height, eliminating the need for additional wiring harnesses required for configuration, which can effectively reduce system complexity, reduce costs, and effectively reduce the total vehicle body volume.

[0046] The control method of the adaptive headlamp system based on motion posture perception provided by the present invention proposes an adaptive illumination angle compensation algorithm for maintaining a stable lighting distance of the vehicle for the adaptive leveling function. The algorithm uses the pitch angular velocity to obtain the pitch posture of the vehicle body, uses the acceleration in the direction perpendicular to the ground to obtain the changing height of the vehicle suspension, and obtains the real-time illumination angle of the headlamp based on the geometric relationship between the vehicle headlamp and the suspension.

[0047] The control method of the adaptive headlamp system based on motion posture perception provided by the present invention limits the single adjustment angle of the headlamp to ensure smooth transition of the angle adjustment in order to avoid discomfort to the driver caused by sudden changes in the lighting angle.

[0048] The control method of the adaptive headlamp system based on motion posture perception provided by the present invention appropriately increases the lighting distance of the headlamp as the vehicle's speed increases, allowing the driver to have a better sight distance, predict road conditions in advance, and avoid danger in advance.

[0049] The present invention provides a control method for an adaptive headlamp system based on motion posture perception. The method analyzes the data characteristics of the acceleration of each axis of a vehicle when passing through a disrepair section according to the characteristics of a disrepair and bumpy road surface, and proposes a method for identifying the disrepair section based on the average standard error of the acceleration of each axis and the average standard error of the acceleration change rate. When a disrepair section is identified, the headlights remain stable to avoid frequent shaking of the headlights caused by incorrect adjustment.

[0050] The control method of the adaptive headlamp system based on motion posture perception provided by the present invention has a corner compensation function for turning. Based on the identification of whether the vehicle is in a turning state, the corner compensation of the headlamp lighting is performed according to the change of the vehicle's yaw angle, thereby ensuring a good field of view for the driver when turning. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 This is a control logic diagram of the adaptive headlamp control system of the present invention.

[0052] Figure 2 The figure is a schematic diagram of the overall structure of the adaptive headlamp control system of the present invention.

[0053] Figure 3 This is a schematic diagram of the vehicle body posture in the initial state of the present invention.

[0054] FIG4( a ) is a schematic diagram of the vehicle according to the present invention in a reclining posture.

[0055] FIG4( b ) is a schematic diagram of the vehicle according to the present invention in a forward leaning posture.

[0056] Figure 5 Schematic diagram of the illumination angle and illumination distance corresponding to the initial aiming illumination distance of the light and the maximum vehicle speed.

[0057] Figure 6 This is a schematic diagram of a vehicle traveling on an ordinary paved road.

[0058] Figure 7 Schematic diagram of a vehicle traveling on a washboard-type road.

[0059] Figure 8 A schematic diagram of a vehicle driving on a bumpy and dilapidated road surface.

[0060] Figure 9 Schematic diagram of headlamp angle compensation when the vehicle turns. DETAILED DESCRIPTION

[0061] The present invention will be described in further detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0062] like Figure 1-2 As shown, the present invention provides an adaptive headlight system based on motion posture perception. The adaptive headlight control system consists of an independent headlight main controller and separate left and right headlight controllers, wherein the main controller is responsible for communicating with other electronic control units of the vehicle through the vehicle body bus. The main controller integrates the headlight adaptive control algorithm, collects the vehicle body posture information collected by the six-axis motion sensor, and calculates the current headlight illumination angle based on the vehicle body posture information. Finally, it sends the headlight control instructions to the left and right headlight controllers through the private bus, and at the same time sends the status of the headlight to the body controller; the left and right headlight controllers have integrated dimming motors and drive units, receive the motor action instructions from the main controller through the private bus, and control the headlights to adjust the illumination angle.

[0063] In one embodiment, the adaptive headlight main controller consists of a main controller MCU (S32K148), a CAN bus transceiver (TJA1043), a LIN bus transceiver (TJA1022), and a motion sensor (MPU6050). The main controller is responsible for receiving headlight control commands and sending current headlight status information via CAN bus 1, communicating with the left and right headlight controllers via CAN bus 2, transmitting headlight on / off commands and status, sending motor adjustment angle information via LIN bus 1, and receiving motor operating status information. A highly integrated motion sensor is integrated into the main controller circuit. The main controller communicates with the six-axis motion sensor via SPI or I2C bus, collecting real-time acceleration information for each axis, and calculating the current headlight adjustment angle based on the adaptive algorithm.

[0064] The left and right headlight controllers consist of a light controller (S32K142), a CAN bus transceiver (TJA1043), LED light clusters, pitch and yaw dimming motors, and a motor driver module (NCV70628). The light controller receives lighting control commands and turns the corresponding light clusters on and off. The pitch dimming motor is responsible for adaptive leveling of the headlight clusters, while the yaw dimming motor is responsible for angle compensation. The dimming motor driver chip integrates a LIN bus transceiver. Upon receiving motor adjustment commands from the main controller, it drives the motors to adjust the illumination angle accordingly.

[0065] As shown in the figure, the present invention also provides a control method for an adaptive headlight system based on motion posture perception, which can adaptively adjust the vehicle headlights according to the different states of the vehicle based on the information collected by the six-axis motion sensor, thereby maintaining the relative stability of the driver's field of view when driving at night.

[0066] 1. Adaptive leveling

[0067] The adaptive leveling function mainly controls the pitch angle of the low beam by sensing the posture of the vehicle body during driving, thereby maintaining the stability of the headlight lighting distance and ensuring the lighting effect for night driving.

[0068] The vehicle posture is sensed through a six-axis motion sensor. Let the vehicle's forward direction (longitudinal direction) be x, the direction perpendicular to the forward direction and parallel to the ground (lateral direction) be y, the direction perpendicular to the ground (vertical direction) be z, and the vehicle's pitch angle be α θ , the yaw angle is Then the acceleration of the vehicle in the three rectangular coordinate axes is a x , a y , a z , the pitch angular velocity is ω θ , the yaw angular velocity is Let the sampling interval of the motion sensor be τ, then the three rectangular coordinate axial velocities v at time t are x , v y , v z It can be expressed as:

[0069] v x (t) = v x (t-τ)+τ·[a x (t)+a x (t-τ)] / 2

[0070] v y (t) = v y (t-τ)+τ·[a y (t)+a y (t-τ)] / 2

[0071] v z (t) = v z (t-τ)+τ·[a z (t)+a z (t-τ)] / 2

[0072] Displacement d in the three rectangular coordinate axes x , d y , d z It can be expressed as:

[0073] d x (t) = d x (t-τ)+τ·[v x (t)+v x (t-τ)] / 2

[0074] d y (t) = d y (t-τ)+τ·[v y (t)+v y (t-τ)] / 2

[0075] d z (t) = d z (t-τ)+τ·[v z (t)+v z (t-τ)] / 2

[0076] The vehicle's pitch angle α θ and yaw angle for:

[0077] α θ (t) = α θ (t-τ)+τ·[ω θ (t)+ω θ (t-τ)] / 2

[0078]

[0079] Among them, ω θ and are the pitch and yaw angular rates of the vehicle, respectively.

[0080] like Figure 3 As shown, in the default initial state of the vehicle, let the initial height of the motion sensor from the ground be H a0 , the vertical distance between the center of the headlight and the motion sensor is H f , the horizontal distance between the center of the headlight and the motion sensor is L f , the height of the headlight center from the ground is H0, the initial aiming angle of the headlight is θ0, and the lighting distance under the initial aiming condition is L0. The relationship between the initial aiming angle, headlight height and lighting distance satisfies:

[0081]

[0082] At the same time, let the vehicle's initial pitch angle α θ0 =0.

[0083] Without considering vehicle speed compensation, when the vehicle pitch attitude changes, let the current pitch angle of the vehicle body be α θ (t), such as Figures 4(a)-4(b) At this time, the motion sensor height H caused by the pitch change of the vehicle body a (t) is:

[0084] H a (t) = H a0 +d z (t) = H a0 +d z (t-τ)+τ·[v z (t)+v z (t-τ)] / 2

[0085] The headlamp height H(t) caused by the vehicle body pitch angle becomes:

[0086]

[0087] To keep the lighting distance stable, there are:

[0088]

[0089] Therefore, the headlamp illumination angle θ(t) without considering vehicle speed compensation is:

[0090]

[0091] The vehicle speed compensation mechanism is introduced to appropriately increase the lighting distance of the headlights when the vehicle speed increases. Figure 5 As shown, the maximum illumination angle allowed by the car headlight is θ max , the maximum angle corresponds to the vehicle's maximum lighting distance L max The upper limit speed v max , and let the minimum speed for angle compensation be v0, when v x When (t)≥v0, the rounded compensation angle Δθ(t) is:

[0092]

[0093] Let the target illumination angle of the headlight under the vehicle speed compensation condition be θ F (t), then:

[0094]

[0095] This angle is the final headlight adjustment angle calculated in real time. By introducing a speed compensation mechanism, drivers can have better sight distance, predict road conditions in advance, and avoid danger in advance.

[0096] Considering that when the car's pitch attitude changes rapidly, the rapid adjustment of the illumination angle will cause the low beam cut-off line to vibrate rapidly, which may cause discomfort to the driver, the single adjustment range of the illumination angle is limited to achieve a smooth adjustment effect. Let the current headlamp illumination angle be θ c (t), the maximum angle adjustment is Δθ st , the actual illumination angle θ of the headlamp after the limiting measure is activated T (t) is:

[0097]

[0098] Among them, θ c (t) is the current headlight angle; Δθ st is the maximum amplitude of angle adjustment, θ P (t) is the target adjustment value of the vehicle headlight pitch angle. When considering vehicle speed compensation, θ P (t) = θ F (t), θ without considering vehicle speed compensation P (t) = θ(t).

[0099] Irradiation angle θ T (t) is the final output of the current single adjustment of the leveling function, which is converted into the adjustment steps of the stepper motor to drive the dimming motor to complete the adjustment of the headlamp illumination pitch angle.

[0100] By limiting the single adjustment angle of the left and right headlights, it is possible to avoid sudden changes in the lighting angle causing discomfort to the driver and ensure a smooth transition of the angle adjustment.

[0101] When a vehicle passes through a continuous bumpy road, the vehicle's pitch attitude will change frequently. To avoid frequent shaking of the lamps due to leveling, the headlight angle should be kept stable when passing through the bumpy road, and the adaptive leveling function should be temporarily turned off until the bumpy road is completely passed.

[0102] When the vehicle is driving on a normal paved road ( Figure 6 ), acceleration in the direction of travel a x and the longitudinal acceleration perpendicular to the ground and a z When a vehicle is traveling on a bumpy road, the acceleration in the direction of travel a x and the longitudinal acceleration a perpendicular to the ground zThere will be irregular repeated vibrations. The acceleration changes of two typical uneven and bumpy roads are as follows: Figure 7 and Figure 8 shown. Figure 7 Longitudinal acceleration a on washboard road x Rapid vibration occurs, and the acceleration in the direction of travel is a x There are also large vibrations; Figure 8 The convex type of disrepair road surface has greater undulations, so the longitudinal acceleration a x The change is larger, and the acceleration in the direction of travel a x The resistance due to the irregularities of the undulating road surface also changes frequently.

[0103] Extract the low-frequency component a of the acceleration in the x-direction and z-direction LFx (t), a LFz (t):

[0104]

[0105] Where t is a sampling time, n is the sampling time point calculated from time t onward when calculating the low-frequency component of acceleration, and N is the window length of data calculation. Subtract the low-frequency component from the acceleration to obtain the high-frequency component of acceleration a HFx (t), a HFz (t):

[0106] a HFx (t) = a x (t)-a LFx (t)

[0107] a HFz (t) = a z (t)-a LFz (t)

[0108] The acceleration variation characteristics on bumpy roads can be evaluated using the following indicators:

[0109] (1) Weighted mean absolute error of acceleration:

[0110] Let the mean absolute error (MAE) of acceleration in the x and z directions be ax (t), MAE az (t) is:

[0111]

[0112] Where M is the data length used for averaging in MAE calculation, m is the sampling time point calculated from time t forward when averaging in MAE calculation, K is the data length for average error calculation, k is the sampling time point calculated from time t forward when calculating the mean absolute error of acceleration, and W ax (k) and Waz (k) are the acceleration weights involved in the calculation within the window.

[0113] The weighted mean absolute error MAE a (t):

[0114]

[0115] Among them, W MAEax (0 <W MAEax <1) and W MAEaz (0 <W MAEaz <1) respectively MAE ax (t) and MAE az The calculation weight of (t).

[0116] (2) Weighted mean absolute error of acceleration slope:

[0117] Define the slope S of the acceleration in the x and z directions x (t), S z (t):

[0118] s x (t) = a HFx (t)-a HFx (t-1)

[0119] s z (t) = a HFz (t)-a HFz (t-1)

[0120] S x (t), S z Mean absolute error (MAE) sx (t), MAE sz (t) is:

[0121]

[0122] Among them, W sx (k) and W sz (k) are the weights of the acceleration slopes involved in the calculation within the window. Weighted mean absolute error MAE s (t):

[0123]

[0124] Among them, W MAEsx (0 <W MAEsx <1) and W MAEsz (0 <W MAEsz <1) respectively MAE sx (t) and MAE sz The calculation weight of (t).

[0125] Define the judgment threshold TH of the mean absolute error of acceleration MAEa and the discrimination threshold TH of the mean absolute error of the acceleration slope MAEs , then the criterion for judging bad roads is:

[0126] MAE a (t)>TH MAEa And MAE s (t)>TH MAEs

[0127] Threshold TH MAEa and TH MAEs The value range is between 0.01 and 0.02. The specific value is determined by the actual vehicle model and the mechanical properties of the suspension. When the suspension is tuned softly, a smaller value can be selected, while when the suspension is tuned hard, a larger value can be selected. The principle of this value selection is to successfully distinguish between bumpy roads and normal roads.

[0128] Typical bumpy roads can be divided into continuous bumpy roads and sudden bumpy roads. Different identification strategies are required to distinguish the two types of bumpy roads. The changes in acceleration and acceleration slope of continuous bumpy roads are relatively continuous, while sudden bumpy roads have large acceleration and acceleration slope only in a short period of time. The two types of bad roads can be identified by setting W ax (k),

[0129] W az (k), W sx (k) and W sz (k) Different calculation weights are used to distinguish:

[0130] (1) Continuous bumpy road surface

[0131] Since the drastically changing acceleration and acceleration slope have a long duration, the calculation quantities (acceleration, acceleration slope) within the window can take the same calculation weight:

[0132] W ax (k) = W az (k) = W sx (k) = W sz (k) = 1 (k = 0, 1, 2, ..., K-1)

[0133] (2) Sudden bumpy road

[0134] The large acceleration and acceleration slope of a sudden bumpy road only occur in a very short period of time. Therefore, different calculation weights are assigned to each calculation quantity (acceleration, acceleration slope) within the window:

[0135] Wax (0)>W ax (1)>W ax (2)>...>W ax (K-1)

[0136] W az (0)>W az (1)>W az (2)>...>W az (K-1)

[0137] W sx (0)>W sx (1)>W sx (2)>...>W sx (K-1)

[0138] W sz (0)>W sz (1)>W sz (2)>...>W sz (K-1)

[0139] Also available:

[0140]

[0141] In the present invention, the weighted mean absolute error (MAE) of the calculated acceleration is a (t) and the weighted mean absolute error MAE of the acceleration slope s (t), the calculation weights corresponding to the continuous bumpy road surface and the calculation weights corresponding to the sudden bumpy road surface are substituted respectively. If the calculation result corresponding to one of the calculation weights satisfies the MAE a (t)>TH MAEa And MAE s (t)>TH MAEs , it is judged that the road surface on which the vehicle is currently traveling is a bumpy road. If the calculation results corresponding to the two calculation weights cannot satisfy the MAE a (t)>TH MAEa And MAE s (t)>TH MAEs , it is judged that the road surface on which the vehicle is traveling is not a bumpy road.

[0142] Based on the characteristics of dilapidated and bumpy roads, this invention analyzes the acceleration data of each axle of a vehicle passing through a dilapidated section. It then proposes a method for identifying dilapidated sections based on the average standard error of each axle's acceleration and the average standard error of the rate of acceleration change. When a dilapidated section is identified, the headlights remain stable, preventing frequent headlight shaking caused by misadjustment. By assigning two different calculation weights to both the acceleration and the acceleration change slope, the method effectively identifies vehicles on both continuously and suddenly bumpy roads, avoiding missed bumpy road identifications due to single weighting.

[0143] 2. Headlamp angle compensation when turning

[0144] When the vehicle's yaw angle satisfies The headlight system with corner compensation can provide additional lighting in the direction of turning, ensuring the brightness of the driver's field of vision and improving nighttime driving safety. Figure 9 As shown. Let the initial turning angle of the headlight be 0, and the horizontal turning angle of the headlight be Determined by the yaw angle of the vehicle when turning. Sometimes, there are

[0145]

[0146] When the vehicle yaw angle Sometimes, there are

[0147]

[0148] in, is the proportional coefficient of the angle compensation, which is calibrated according to the specific configuration of the headlamp. The value range is 0.8 to 1.2. The value of this coefficient depends on the horizontal irradiation angle range of the headlamp beam. When the beam angle is narrow, the proportional coefficient is appropriately increased, and when the beam angle is wide, the proportional coefficient is appropriately reduced. is the vehicle yaw angle at time t, is the vehicle yaw angle at time (t-τ), is the horizontal angle compensation threshold, is the vehicle yaw angular velocity at time t, is the vehicle yaw rate at time (t-τ).

[0149] When the vehicle's yaw angle satisfies The left and right headlights do not perform corner compensation.

[0150] When adjusting the horizontal angles of the left and right headlights of the vehicle, if Then the horizontal turning angles of the left and right headlights of the vehicle are restored to:

[0151]

[0152] in, is the vehicle yaw rate threshold, which is a positive value close to zero.

[0153] As a preferred option, The value range is 10°~20°.

[0154] The corner compensation function for turning can identify whether the vehicle is in a turning state. Based on the above, the headlights are compensated for the changes in the vehicle's yaw angle to ensure the driver has a good field of vision when turning.

[0155] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and implementation methods. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A control method for an adaptive headlight system based on motion posture perception, characterized in that: The adaptive front lighting system based on motion posture perception includes: The six-axis motion sensor used is used to collect the longitudinal acceleration, lateral acceleration, vertical acceleration, pitch angular velocity and yaw angular velocity of the vehicle body; a main controller electrically connected to the six-axis motion sensor, receiving information collected by the six-axis motion sensor, and calculating headlamp control information based on the received information; a left headlamp dimming drive mechanism, electrically connected to the main controller, for adjusting the pitch angle and horizontal rotation angle of the left headlamp according to the headlamp control information; a right headlamp dimming drive mechanism, electrically connected to the main controller, for adjusting the pitch angle and horizontal rotation angle of the right headlamp according to the headlamp control information; The control method includes: The longitudinal acceleration of the vehicle body is collected by a six-axis motion sensor x , lateral acceleration a y , vertical acceleration a z , pitch angular velocity ω θ and yaw rate When the vehicle is moving straight and its pitch attitude changes, the pitch angles of the left and right headlights at time t are controlled as follows: in: Where L0 is the lighting distance of the vehicle headlight under the initial aiming condition; H a0 is the initial height of the six-axis motion sensor from the ground; d z (t-τ) is the vertical displacement of the vehicle at time (t-τ); τ is the sensor sampling interval; v z (t) is the vertical velocity of the vehicle at time t, v z (t-τ) is the vertical velocity of the vehicle at the moment (t-τ); H f L is the vertical distance between the center of the headlight and the six-axis motion sensor; f is the horizontal distance between the center of the headlight and the six-axis motion sensor; α θ (t-τ) is the pitch angle of the vehicle at time (t-τ); ω θ (t) is the pitch angular velocity of the vehicle at time t, ω θ (t-τ) is the pitch angular velocity of the vehicle at time (t-τ); The longitudinal speed v at time t x (t) is compared with the angle compensation speed threshold v0. When v x When (t)≥v0, the pitch angles of the left and right headlights of the vehicle at time t are controlled as follows: Among them, θ max is the maximum illumination angle of the car headlight, v max is θ max The upper speed limit for the vehicle to achieve the maximum lighting distance, θ0 is the initial aiming angle of the headlight; When the vehicle passes through bumpy roads, the left and right headlights of the vehicle are controlled to maintain the current pitch angle; The method for judging the bumpy road surface is as follows: Calculate the weighted mean absolute error (MAE) of the vehicle's longitudinal and vertical accelerations a (t) and the weighted mean absolute error (MAE) of the vehicle's longitudinal and vertical acceleration slopes s (t); If MAE a (t)>TH MAEa And MAE s (t)>TH MAEs , it is determined that the road surface on which the vehicle is currently traveling is a bumpy road; Among them, TH MAEa is the threshold value of the mean absolute error of acceleration, TH MAEs is the discrimination threshold of the mean absolute error of the acceleration slope.

2. The control method of the adaptive headlight system based on motion posture perception according to claim 1, characterized in that: During the process of adjusting the pitch angle of the headlights, the single adjustment range is limited, and the pitch angles of the left and right headlights of the vehicle after a single adjustment are controlled to be: Among them, θ c (t) is the current headlight angle; Δθ st is the maximum amplitude of angle adjustment, θ P (t) is the target adjustment value of the vehicle headlight pitch angle.

3. The control method of the adaptive headlight system based on motion posture perception according to claim 2, characterized in that: Also includes: When the vehicle yaw angle When the horizontal angles of the left and right headlights of the vehicle are adjusted: When the vehicle yaw angle When , the horizontal turning angles of the left and right headlights of the vehicle are controlled as follows: When the vehicle yaw angle When , the horizontal turning angles of the left and right headlights of the vehicle are controlled as follows: in, is the vehicle yaw angle at time t, is the vehicle yaw angle at time (t-τ), is the proportional coefficient of the angle compensation, is the horizontal angle compensation threshold, is the vehicle yaw angular velocity at time t, is the vehicle yaw rate at time (t-τ).

4. The control method of the adaptive headlight system based on motion posture perception according to claim 3, characterized in that: When adjusting the horizontal angles of the left and right headlights of the vehicle, if Then the horizontal turning angles of the left and right headlights of the vehicle are restored to: in, is the vehicle yaw rate threshold, which is a positive value close to zero.

5. The control method of the adaptive headlight system based on motion posture perception according to claim 4, characterized in that: The value range is 10°~20°.

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