Vehicle control method and system and vehicle

Abstract

The invention provides a vehicle control method and system and a vehicle, and relates to the technical field of vehicle control, and the method comprises the steps that according to the vehicle speed, the fording depth and the cross sectional area of the current vehicle, the resistance borne by the current vehicle is determined; according to the resistance borne by the current vehicle, the driving state information of the current vehicle and the underwater obstacle information, the collision time between the current vehicle and the obstacle is calculated; determining a target control strategy according to the collision time and the vehicle state of the current vehicle; and controlling the current vehicle to brake according to the target control strategy. The corresponding target control strategy is determined for braking according to the real-time condition of the underwater environment in combination with the underwater resistance factor, the vehicle state and the collision time of the vehicle and the obstacle, the underwater collision risk of the vehicle can be effectively reduced, and the driving safety of the vehicle in the underwater scene is improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a vehicle control method, system and vehicle. Background Art

[0002] At present, emergency obstacle avoidance technology has been widely used in the field of smart cars. However, most of the existing smart cars do not have the floating function and lack an effective active safety system. In addition, in wading or floating scenes, due to the turbid water quality, it is difficult for the driver to effectively judge the underwater obstacle information, which can easily cause a collision and pose a threat to the driver's personal safety.

[0003] Therefore, a new vehicle control method is urgently needed. Summary of the invention

[0004] In view of the above problems, the embodiments of the present application provide a vehicle control method, system and vehicle to overcome the above problems or at least partially solve the above problems.

[0005] In a first aspect of an embodiment of the present application, a vehicle control method is provided, the method comprising:

[0006] Determining the resistance experienced by the current vehicle according to the current vehicle speed, wading depth and cross-sectional area of ​​the vehicle;

[0007] Calculating the collision time between the current vehicle and the obstacle according to the resistance experienced by the current vehicle, the driving state information of the current vehicle and the underwater obstacle information;

[0008] Determining a target control strategy according to the collision time and the vehicle state of the current vehicle;

[0009] Control the current vehicle to brake according to the target control strategy.

[0010] Optionally, determining a target control strategy according to the collision time and the vehicle state of the current vehicle includes:

[0011] When the collision time is in the first interval and the vehicle state is a wading state or a floating state, determining that the target control strategy is a first strategy, wherein the first strategy is to control the braking system of the current vehicle to brake each wheel of the current vehicle;

[0012] When the collision time is in the second interval and the vehicle state is a wading state or a floating state, determining that the target control strategy is a second strategy, and the second strategy is to change the rear wheel posture angle of the current vehicle;

[0013] When the collision time is in the third interval and the vehicle state is in a floating state, determining that the target control strategy is a third strategy, and the third strategy is to control the rear wheels of the current vehicle to reverse;

[0014] When the collision time is in the fourth interval and the vehicle state is a wading state or a floating state, the target control strategy is determined to be an emergency strategy, and the emergency strategy is to control the current vehicle to change lanes according to a lane change curve in a current feasible area.

[0015] Optionally, the vehicle state is obtained based on the detected wading depth of the current vehicle and a driving mode pre-input by a driver, and the method further includes:

[0016] When the current vehicle is in a floating state and the rear wheels of the current vehicle are controlled to change their posture angles, determining whether the current vehicle will collide with the obstacle;

[0017] In the case that the current vehicle is about to collide with the obstacle, the rear wheels of the current vehicle are driven to reverse by a driving motor.

[0018] Optionally, when the target control strategy is the first strategy, controlling the current vehicle to brake according to the target control strategy includes:

[0019] When the current vehicle is in a wading state, a first braking force of a braking system of the current vehicle is determined based on the resistance-vehicle speed-wading depth curve, and each wheel of the current vehicle is braked based on the first braking force.

[0020] Optionally, when the target control strategy is the first strategy, controlling the current vehicle to brake according to the target control strategy includes:

[0021] When the current vehicle is in a floating state, each motor of the current vehicle is controlled to stop providing driving torque, and a braking system of the current vehicle is controlled to brake each wheel of the current vehicle.

[0022] Optionally, when the target control strategy is the second strategy, controlling the current vehicle to brake according to the target control strategy includes:

[0023] Obtaining a maximum steering angle of a rear wheel independent steering mechanism of the current vehicle;

[0024] Based on the maximum steering angle, the rear wheels of the current vehicle are controlled to steer according to the maximum steering angle to change the posture angle of the rear wheels, wherein the left rear wheel and the right rear wheel of the current vehicle steer in opposite directions.

[0025] Optionally, when the target control strategy is the emergency strategy, controlling the current vehicle to brake according to the target control strategy includes:

[0026] Determining the lane changing curve in the current feasible area according to the driving state information and the obstacle information;

[0027] Control the current vehicle to change lanes according to the lane changing curve.

[0028] Optionally, controlling the current vehicle to change lanes according to the lane-changing curve includes:

[0029] Obtaining a longitudinal speed error and a lateral speed error of the current vehicle;

[0030] determining a second braking force of a braking system of the current vehicle according to the longitudinal speed error;

[0031] According to the lateral error, the steering angle of the front wheel of the current vehicle is calculated by a PID algorithm;

[0032] Calculating the steering angle of the rear wheels of the current vehicle according to the steering angle of the front wheels;

[0033] The current vehicle is controlled to change lanes according to the second braking force, the steering angle of the front wheels, and the steering angle of the rear wheels.

[0034] In a second aspect of an embodiment of the present application, a vehicle control system is provided, the system comprising:

[0035] A first determination module, configured to determine the resistance experienced by the current vehicle according to the current vehicle speed, wading depth and cross-sectional area;

[0036] A calculation module, used for calculating the collision time between the current vehicle and the obstacle according to the resistance suffered by the current vehicle, the driving state information of the current vehicle and the underwater obstacle information;

[0037] A second determination module, configured to determine a target control strategy according to the collision time and the vehicle state of the current vehicle;

[0038] A control module is used to control the current vehicle to brake according to the target control strategy.

[0039] Optionally, the target control strategy is determined according to the collision time and the vehicle state of the current vehicle, and the second determination module includes:

[0040] A first determination submodule is used to determine that the target control strategy is a first strategy when the collision time is in a first interval and the vehicle state is a wading state or a floating state, and the first strategy is to control the braking system of the current vehicle to brake each wheel of the current vehicle;

[0041] A second determination submodule is used to determine that the target control strategy is a second strategy when the collision time is in a second interval and the vehicle state is a wading state or a floating state, and the second strategy is to change the rear wheel posture angle of the current vehicle;

[0042] A third determination submodule, configured to determine that the target control strategy is a third strategy when the collision time is in a third interval and the vehicle state is a floating state, wherein the third strategy is to control the rear wheels of the current vehicle to reverse;

[0043] The fourth determination submodule is used to determine that the target control strategy is an emergency strategy when the collision time is in a fourth interval and the vehicle state is a wading state or a floating state. The emergency strategy is to control the current vehicle to change lanes according to the lane change curve in the current feasible area.

[0044] Optionally, the vehicle state is obtained based on the detected wading depth of the current vehicle and a driving mode pre-input by a driver, and the method further includes:

[0045] A judgment submodule, used for judging whether the current vehicle will collide with the obstacle when the current vehicle is in a floating state and the rear wheels of the current vehicle are controlled to change their posture angles;

[0046] The driving submodule is used to drive the rear wheels of the current vehicle to reverse by driving the motor when the current vehicle is about to collide with the obstacle.

[0047] Optionally, when the target control strategy is the first strategy, the controlling the current vehicle to brake according to the target control strategy, the control module includes:

[0048] The first braking submodule is used to determine a first braking force of the braking system of the current vehicle based on the resistance-vehicle speed-wading depth curve when the current vehicle is in a wading state, and brake each wheel of the current vehicle based on the first braking force.

[0049] Optionally, when the target control strategy is the first strategy, the controlling the current vehicle to brake according to the target control strategy, the control module includes:

[0050] The second braking submodule is used to control each motor of the current vehicle to stop providing driving torque and control the braking system of the current vehicle to brake each wheel of the current vehicle when the current vehicle is in a floating state.

[0051] Optionally, when the target control strategy is the second strategy, the current vehicle is controlled to brake according to the target control strategy, and the control module includes:

[0052] An acquisition submodule, used to acquire a maximum steering angle of a rear wheel independent steering mechanism of the current vehicle;

[0053] The steering submodule is used to control the rear wheels of the current vehicle to steer according to the maximum steering angle based on the maximum steering angle to change the posture angle of the rear wheels, wherein the left rear wheel and the right rear wheel of the current vehicle steer in opposite directions.

[0054] Optionally, when the target control strategy is the emergency strategy, controlling the current vehicle to brake according to the target control strategy includes:

[0055] a fifth determining submodule, configured to determine the lane changing curve in the current feasible area according to the driving state information and the obstacle information;

[0056] The lane changing submodule is used to control the current vehicle to change lanes according to the lane changing curve.

[0057] Optionally, the controlling the current vehicle to change lanes according to the lane changing curve, the lane changing submodule includes:

[0058] An acquisition subunit, used to acquire a longitudinal speed error and a lateral speed error of the current vehicle;

[0059] a determination subunit, configured to determine a second braking force of a braking system of the current vehicle according to the longitudinal speed error;

[0060] A first calculation subunit, configured to calculate a steering angle of a front wheel of the current vehicle by using a PID algorithm according to the lateral error;

[0061] A second calculation subunit, configured to calculate a steering angle of a rear wheel of the current vehicle according to the steering angle of the front wheel;

[0062] The lane changing subunit is used to control the current vehicle to change lanes according to the second braking force, the steering angle of the front wheels, and the steering angle of the rear wheels.

[0063] A third aspect of an embodiment of the present application provides a vehicle, which includes the vehicle control system described in the second aspect of the present application, and / or executes the vehicle control method described in the first aspect of the present application.

[0064] Beneficial effects of the embodiments of the present application:

[0065] The embodiment of the present application provides a vehicle control method, the method comprising: determining the resistance of the current vehicle according to the speed, wading depth and cross-sectional area of ​​the current vehicle; calculating the collision time between the current vehicle and the obstacle according to the resistance of the current vehicle, the driving state information of the current vehicle and the underwater obstacle information; determining a target control strategy according to the collision time and the vehicle state of the current vehicle; and controlling the current vehicle to brake according to the target control strategy. The present application can effectively reduce the risk of underwater collision of the vehicle and improve the driving safety of the vehicle in underwater scenes by determining the corresponding target control strategy for braking according to the real-time situation of the underwater environment, combined with the underwater resistance factor, the vehicle state and the collision time between the vehicle and the obstacle. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0067] Figure 1 It is a schematic diagram of the steps of a vehicle control method provided by an embodiment of the present application;

[0068] Figure 2 It is a flowchart of a multi-stage braking strategy provided by an embodiment of the present application;

[0069] Figure 3 It is a schematic diagram of a resistance-vehicle speed-wading depth curve provided in an embodiment of the present application;

[0070] Figure 4 This is a schematic diagram of a rear wheel outward expansion structure provided in an embodiment of the present application;

[0071] Figure 5 is a flowchart of a vehicle control method provided in an embodiment of the present application;

[0072] Figure 6is a structural diagram of a perception module provided in an embodiment of the present application;

[0073] Figure 7 It is a structural schematic diagram of a vehicle control system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0074] The exemplary embodiments of the present application will be described in more detail below in conjunction with the accompanying drawings in the embodiments of the present application. Although the exemplary embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present application and to enable the scope of the present application to be fully communicated to those skilled in the art.

[0075] In a first aspect of the embodiments of the present application, a vehicle control method is provided, which is applied to a VCU (Vehicle Control Unit) of a vehicle, such as Figure 1 As shown, the method includes:

[0076] Step S101, determining the resistance experienced by the current vehicle according to the current vehicle speed, wading depth and cross-sectional area;

[0077] Specifically, in this step, it is first necessary to obtain information such as the current vehicle's speed, wading depth, and cross-sectional area. The vehicle information submodule of the current vehicle can be used to identify the specific operation of the driver of the current vehicle, such as the throttle depth, steering wheel angle, and brake pedal depth to obtain the dynamic situation of the current vehicle, such as the vehicle speed information. In addition, other dynamic situations can also be obtained, such as longitudinal acceleration or yaw angular velocity information. In practical applications, the vehicle information submodule can be a vehicle-mounted sensor, etc.

[0078] In this step, the wading depth information of the vehicle can be detected by the wading detection submodule of the current vehicle. In actual applications, the wading detection submodule can be a water depth sensor or a liquid level sensor. By real-time monitoring the water depth of the current vehicle's location, utilizing the special design of the vehicle chassis, combined with sensors and other devices, the wading depth information of the current vehicle's location can be inferred.

[0079] In this step, the cross-sectional area of ​​the vehicle can be calculated based on the vehicle's geometry and dimensions.

[0080] In this application, different water depths, different vehicles and different speeds can be used to conduct real vehicle tests to determine the relationship between vehicle speed, water depth and cross-sectional area and resistance. For example, different combinations of vehicles, water depths and speeds can be selected to prepare vehicles, measuring equipment (such as sensors, flow meters) and water test sites required for the test. Tests are carried out in the selected waters to ensure that the water depth can cover the required range. Different vehicle types (such as sedans, SUVs, trucks, etc.) and different speeds are selected for testing. In each case, relevant data such as the actual speed, water depth and cross-sectional area of ​​the vehicle are recorded. Data during the test process are collected in real time using equipment such as on-board sensors, water depth sensors and cameras. The collected data are sorted and analyzed to establish a relationship model between vehicle speed, water depth and cross-sectional area and resistance. Among them, statistical analysis or mathematical modeling methods can be used to establish a relationship model between vehicle speed, water depth and cross-sectional area and resistance based on the test data. Another part of the data is used to verify the established model to ensure its accuracy and reliability. The influence of vehicle speed, water depth and cross-sectional area on resistance is summarized based on the established model.

[0081] Optionally, the present application can also obtain information such as road conditions, pedestrians, vehicles, and water surface conditions in front of the vehicle through the visual submodule. The point cloud data collected by the laser radar submodule can be used for accurate detection and positioning of obstacles above the water surface. The millimeter wave radar submodule senses the vehicle operation status in a large range and enhances the vehicle's long-distance perception ability. The ultrasonic radar submodule detects underwater obstacle information and improves the vehicle's perception ability in wading or floating water.

[0082] Step S102, calculating the collision time between the current vehicle and the obstacle according to the resistance experienced by the current vehicle, the driving state information of the current vehicle and the underwater obstacle information;

[0083] Specifically, in this step, the driving status information of the current vehicle includes: the vehicle weight, the speed, the position, the driving force and the braking force of the current vehicle; the underwater obstacle information includes: the speed and position of the obstacle.

[0084] In this embodiment, the acceleration of the current vehicle is determined based on the resistance of the current vehicle, the driving force of the current vehicle, the braking force of the current vehicle, and the weight of the current vehicle, which is specifically expressed by the following formula (1):

[0085]

[0086] Among them, a c Indicates the current vehicle acceleration; F t Indicates the current driving force of the vehicle; F wrepresents the resistance of the current vehicle; m represents the weight of the current vehicle.

[0087] Furthermore, the acceleration of the obstacle can be estimated by the information measured by the sensor installed on the vehicle, so that the relative acceleration between the current vehicle and the obstacle can be determined, as shown in the following formula (2):

[0088] a rel =a c -a o (2)

[0089] Among them, a rel Represents relative acceleration; a o Represents the acceleration of the obstacle.

[0090] Furthermore, according to the current position of the vehicle and the position of the obstacle, the relative distance between the two can be determined.

[0091] Furthermore, the collision time between the current vehicle and the obstacle is calculated by the following formula (3):

[0092]

[0093] Where TTC is the time to collision; s is the distance between the current vehicle and the obstacle; d is the preset safe stopping distance; v rel Relative speed is the current vehicle speed minus the speed of the obstacle; a rel =0 means the relative acceleration is 0.

[0094] Preferably, when the relative acceleration between the current vehicle and the obstacle is not 0, the collision time between the current vehicle and the obstacle can be calculated by the following formula (4):

[0095]

[0096] Step S103, determining a target control strategy according to the collision time and the vehicle state of the current vehicle;

[0097] Specifically, in this step, a target control strategy is formulated according to the collision time calculated in step 3 and the current vehicle state, wherein the current vehicle state includes a wading state and a floating state. Therefore, in this step, a corresponding target control strategy is applied according to different collision times and wading states or floating states.

[0098] Step S104, controlling the current vehicle to brake according to the target control strategy.

[0099] Specifically, after the target control strategy is determined, the current vehicle is controlled to brake according to the determined target control strategy based on the collision time between the current vehicle and the obstacle and the vehicle state of the current vehicle.

[0100] This application determines the corresponding target control strategy for braking according to the real-time situation of the underwater environment, combined with the underwater resistance factors, vehicle status and the collision time between the vehicle and the obstacle. It can effectively reduce the risk of underwater collision of the vehicle and improve the driving safety of the vehicle in underwater scenes.

[0101] In a preferred embodiment, determining the target control strategy according to the collision time and the vehicle state of the current vehicle includes:

[0102] When the collision time is in the first interval and the vehicle state is a wading state or a floating state, determining that the target control strategy is a first strategy, wherein the first strategy is to control the braking system of the current vehicle to brake each wheel of the current vehicle;

[0103] When the collision time is in the second interval and the vehicle state is a wading state or a floating state, determining that the target control strategy is a second strategy, and the second strategy is to change the rear wheel posture angle of the current vehicle;

[0104] When the collision time is in the third interval and the vehicle state is in a floating state, determining that the target control strategy is a third strategy, and the third strategy is to control the rear wheels of the current vehicle to reverse;

[0105] When the collision time is in the fourth interval and the vehicle state is a wading state or a floating state, the target control strategy is determined to be an emergency strategy, and the emergency strategy is to control the current vehicle to change lanes according to a lane change curve in a current feasible area.

[0106] Specifically, this embodiment determines different target control strategies according to the collision time between the current vehicle and the obstacle and the different vehicle states of the current vehicle, such as Figure 2 A schematic flow chart of a multi-stage braking strategy is shown, which specifically includes:

[0107] When the collision time is in the first interval and the vehicle state is in the wading state or the floating state, the target control strategy is determined to be the first strategy, that is, the braking system of the current vehicle is controlled to brake each wheel, which can help the vehicle slow down and avoid collision with obstacles as much as possible, that is, it provides the first layer of protection to avoid the current vehicle from colliding with obstacles.

[0108] When the collision time is in the second interval, the vehicle is in a wading state or a floating state. At this time, the target control strategy is determined to be the second strategy, that is, changing the rear wheel posture angle of the current vehicle. By adjusting the rear wheel posture angle, additional braking force is provided for the current vehicle, which provides a second layer of protection to prevent the current vehicle from colliding with obstacles.

[0109] When the collision time is in the third interval and the vehicle state is in a floating state, the target control strategy is determined to be the third strategy, that is, the rear wheels of the current vehicle are controlled to reverse, thereby providing additional braking deceleration for the current vehicle in the floating state, further avoiding the current vehicle from colliding with obstacles, that is, providing a third layer of protection to avoid the current vehicle from colliding with obstacles.

[0110] When the collision time is in the fourth interval, and the vehicle state is in the wading state or the floating state, the target control strategy is determined to be the emergency strategy, that is, the current vehicle is controlled to change lanes according to the lane change curve in the current feasible area. This can help the vehicle leave the collision path as soon as possible and avoid collision with obstacles, that is, it provides a fourth layer of protection to avoid collision between the current vehicle and obstacles. In actual applications, the time period corresponding to the first interval, the time period corresponding to the second interval, the time period corresponding to the third interval, and the time period corresponding to the fourth interval decrease in sequence.

[0111] This embodiment uses different target control strategies to avoid collision between the current vehicle and obstacles according to different collision times and vehicle states, so as to more flexibly deal with possible collision risks in underwater environments, thereby improving the safety and stability of the vehicle.

[0112] In a preferred embodiment, the vehicle state is obtained based on the detected wading depth of the current vehicle and the driving mode pre-input by the driver, and the method further includes:

[0113] When the current vehicle is in a floating state and the rear wheels of the current vehicle are controlled to change their posture angles, determining whether the current vehicle will collide with the obstacle;

[0114] In the case that the current vehicle is about to collide with the obstacle, the rear wheels of the current vehicle are driven to reverse by a driving motor.

[0115] Specifically, the vehicle state mentioned in the present application is determined based on the wading depth of the current vehicle detected by the wading detection module, and the driving mode judged and pre-input by the driver based on driving experience. In actual applications, the driver will pre-activate the vehicle's driving mode, such as wading mode or floating mode, based on the observed depth information of the vehicle body immersed in water. The vehicle's VCU will determine whether the current vehicle state is a wading state or a floating state based on the wading depth of the current vehicle detected by the wading detection module and the driving mode actively input by the driver.

[0116] Furthermore, when the current vehicle is in a floating state, when the collision time is in the second interval, the rear wheels of the current vehicle are controlled to change the posture angle based on the second strategy. At this time, it is necessary to judge in real time whether the current vehicle will still collide with the obstacle in front when the rear wheels of the current vehicle change the posture angle. If it is judged that the current vehicle will still collide with the obstacle in front, it is necessary to further control the drive motor to drive the rear wheels of the current vehicle to reverse based on the third strategy, thereby providing additional braking deceleration for the current vehicle in the floating state, which can effectively and timely avoid the collision between the current vehicle and the obstacle.

[0117] In a preferred embodiment, when the target control strategy is the first strategy, controlling the current vehicle to brake according to the target control strategy includes:

[0118] When the current vehicle is in a wading state, a first braking force of a braking system of the current vehicle is determined based on the resistance-vehicle speed-wading depth curve, and each wheel of the current vehicle is braked based on the first braking force.

[0119] Specifically, in this embodiment, the relative relationship between resistance, vehicle speed and wading depth is determined through actual vehicle tests, and the following is formulated: Figure 3 The resistance-vehicle speed-wading depth curve is shown in the figure. In the resistance-vehicle speed-wading depth curve, the horizontal axis represents the speed of the vehicle relative to the water flow. In actual applications, the water flow speed is generally assumed to be 0, and the relative speed is the vehicle speed. The vertical axis represents the resistance the vehicle is currently experiencing in the water. The three curves A1, A2, and A3 represent the different resistance characteristic curves encountered by the vehicle at different wading depths. Generally speaking, for the same vehicle, the deeper the wading depth, the greater the resistance the vehicle will experience at the same speed.

[0120] Furthermore, when the current vehicle is in a wading state, the resistance encountered by the current vehicle can be determined based on the resistance-vehicle speed-wading depth curve, as well as the vehicle speed and wading depth information of the current vehicle, and the first braking force of the braking system of the current vehicle can be determined based on the resistance encountered by the current vehicle and the acceleration of the current vehicle. The braking system brakes each wheel of the current vehicle according to the determined first braking force.

[0121] In a preferred embodiment, when the target control strategy is the first strategy, controlling the current vehicle to brake according to the target control strategy includes:

[0122] When the current vehicle is in a floating state, each motor of the current vehicle is controlled to stop providing driving torque, and a braking system of the current vehicle is controlled to brake each wheel of the current vehicle.

[0123] Specifically, in this embodiment, when the target control strategy is the first strategy and the vehicle is currently in a floating state, the vehicle's VCU will instruct each drive motor to stop providing drive torque. This is done to prevent the operation of the motor from increasing the speed of the vehicle, thereby exacerbating the possible risk of collision.

[0124] At the same time, the vehicle's VCU will activate the braking system to brake each wheel of the vehicle. The braking system can adjust the braking force according to the specific situation to ensure that the vehicle can stop stably in the water and prevent it from moving forward.

[0125] In a preferred embodiment, when the target control strategy is the second strategy, controlling the current vehicle to brake according to the target control strategy includes:

[0126] Obtaining a maximum steering angle of a rear wheel independent steering mechanism of the current vehicle;

[0127] Based on the maximum steering angle, the rear wheels of the current vehicle are controlled to steer according to the maximum steering angle to change the posture angle of the rear wheels, wherein the left rear wheel and the right rear wheel of the current vehicle steer in opposite directions.

[0128] Specifically, in this embodiment, first, the VCU of the vehicle needs to obtain the maximum steering angle of the rear wheel independent steering mechanism currently equipped on the vehicle, which can be obtained through the vehicle's sensor system or pre-determined parameters, and this application does not make specific limitations here.

[0129] Furthermore, after obtaining the maximum steering angle of the rear-wheel independent steering mechanism, the VCU of the vehicle will instruct the rear-wheel independent steering mechanism to control the rear wheels of the vehicle to steer according to the maximum steering angle.

[0130] Specifically, the independent rear-wheel steering mechanism will control the left and right rear wheels of the vehicle to steer in opposite directions respectively. As the attitude angles of the left and right rear wheels change accordingly, the contact area between the rear wheels and the water is increased, thereby increasing the resistance encountered by the current vehicle in the water, providing additional braking force for the current vehicle.

[0131] In one embodiment, there is provided Figure 4 The schematic diagram of a structure with outward-extended rear wheels is shown. It should be noted that the left rear wheel and the right rear wheel of the vehicle can also be retracted, which can also increase the contact area with water.

[0132] In this embodiment, the rear wheels are controlled to steer according to the maximum steering angle by the rear wheel independent steering mechanism, so that the posture angle of the rear wheels can be changed, the contact area between the rear wheels and the water is increased, and the resistance encountered by the current vehicle in the water is increased, thereby providing additional braking force for the current vehicle.

[0133] In a preferred embodiment, when the target control strategy is the emergency strategy, controlling the current vehicle to brake according to the target control strategy includes:

[0134] Determining the lane changing curve in the current feasible area according to the driving state information and the obstacle information;

[0135] Control the current vehicle to change lanes according to the lane changing curve.

[0136] Specifically, in this embodiment, it is necessary to first obtain the driving status information and obstacle information of the current vehicle, wherein the driving status information of the current vehicle includes: the vehicle weight of the current vehicle, the speed of the current vehicle, the position of the current vehicle, the driving force of the current vehicle and the braking force of the current vehicle, etc.; the underwater obstacle information includes: the speed of the obstacle, the position of the obstacle, etc.

[0137] Furthermore, according to the driving state information and obstacle information of the current vehicle, the lane change curve of the current feasible area is determined, and the current vehicle is controlled to change lanes according to the determined lane change curve. The lane change curve is shown in the following formula (5):

[0138]

[0139] Where X(t) represents the horizontal coordinate of the current vehicle in the geodetic coordinate system corresponding to time t; Y(t) represents the vertical coordinate of the current vehicle in the geodetic coordinate system corresponding to time t; i and q i All are coefficients.

[0140] In this embodiment, a suitable lane change curve is calculated based on the vehicle driving state information and obstacle information, and the vehicle is controlled to change lanes according to the curve, which can help the vehicle effectively respond to emergency situations, avoid collisions or mitigate the consequences of collisions. This method can improve vehicle safety and driver confidence while minimizing the risk of accidents.

[0141] In a preferred embodiment, controlling the current vehicle to change lanes according to the lane changing curve includes:

[0142] Obtaining a longitudinal speed error and a lateral speed error of the current vehicle;

[0143] determining a second braking force of a braking system of the current vehicle according to the longitudinal speed error;

[0144] According to the lateral error, the steering angle of the front wheel of the current vehicle is calculated by a PID algorithm;

[0145] Calculating the steering angle of the rear wheels of the current vehicle according to the steering angle of the front wheels;

[0146] The current vehicle is controlled to change lanes according to the second braking force, the steering angle of the front wheels, and the steering angle of the rear wheels.

[0147] Specifically, in this embodiment, first, the longitudinal speed error and lateral error of the current vehicle need to be obtained. The longitudinal speed error represents the difference between the current speed of the vehicle and the expected speed, while the lateral error represents the deviation between the current position of the vehicle and the expected trajectory.

[0148] In this embodiment, the longitudinal velocity error is expressed as follows:

[0149] V e rr (t) = V ref (t ) - V(t ) (6)

[0150] Among them, V err (t) represents the longitudinal velocity error; V ref (t) represents the desired longitudinal velocity; V(t) represents the current vehicle velocity.

[0151] Optionally, this embodiment further provides a method for calculating the brake pressure of the brake system based on a PID algorithm, as shown in the following formula (7):

[0152]

[0153] Where, u(t) represents the braking pressure; K p , K i , K dRepresents the coefficient.

[0154] In this embodiment, the lateral error is expressed as follows:

[0155] e(t)=C 1 e y (t)+C 2 θ e (t) (8)

[0156] Where, e(t) represents the lateral error; C 1 , C 2 represents the weight coefficient; e y (t) represents the lateral tracking error; θ e (t) represents the yaw angle error.

[0157] Optionally, this embodiment further provides a calculation formula for the lateral tracking error and the yaw angle error. Specifically, the lateral tracking error is shown in the following formula (9):

[0158] e y (t) = l d (t)sinθ e (t) (9)

[0159] in, represents the distance between the current vehicle and the obstacle; x(t) represents the horizontal coordinate of the current vehicle at time t; y(t) represents the vertical coordinate of the current vehicle at time t; X(t) represents the expected horizontal coordinate of the current vehicle at time t; Y(t) represents the expected vertical coordinate of the current vehicle at time t; θ e (t) = ψ ref (t)-ψ(t) represents the yaw angle error; ψ ref (t) represents the desired heading angle; ψ(t) represents the heading angle.

[0160] Further, based on the longitudinal speed error, the VCU of the vehicle will determine the second braking force that the braking system needs to apply. The second braking force is the additional braking force that the braking system needs to apply during the lane change process to adjust the speed of the vehicle to ensure safe lane change. The specific calculation method is shown in formula (7), which will not be repeated in this embodiment.

[0161] Furthermore, according to the lateral error, the PID algorithm is used to calculate the current steering angle of the front wheels of the vehicle. The PID algorithm is a commonly used control algorithm that controls the system by adjusting the three parameters of proportion, integration and differentiation so that the steering angle of the front wheels can reach the desired value as quickly as possible and remain stable.

[0162] In this embodiment, a calculation formula (10) for the steering angle of the front wheels is provided:

[0163]

[0164] Among them, δ f Indicates the steering angle of the front wheels.

[0165] Furthermore, the steering angle of the rear wheels is calculated based on the steering angle of the front wheels and the steering characteristics of the vehicle.

[0166] In this embodiment, a calculation formula (11) for the steering angle of the rear wheels is provided:

[0167]

[0168] Among them, δ r represents the rear wheel steering angle; a represents the distance from the vehicle's center of mass to the front axle; b represents the distance from the vehicle's center of mass to the rear axle; L represents the vehicle's wheelbase; k 1 represents the equivalent cornering stiffness of the front axle; k 2 Represents the equivalent cornering stiffness of the rear axle.

[0169] Finally, based on the second braking force, the steering angle of the front wheels and the steering angle of the rear wheels, the vehicle's VCU will control the vehicle to change lanes. During the lane change process, the braking system and steering system will be adjusted simultaneously to allow the vehicle to change lanes safely along the lane change curve, thereby helping the vehicle to leave the collision path as quickly as possible and avoid collision with obstacles.

[0170] In a preferred embodiment, there is provided Figure 5 The flowchart of a vehicle control method shown in FIG. 1 specifically includes:

[0171] First, the data obtained by the vehicle's perception module is preprocessed and fused. These data include vehicle speed, wading depth, cross-sectional area, driving status information, and obstacle information. Based on the processed data, the collision time TTC between the current vehicle and the obstacle is calculated.

[0172] Further, determine whether the collision time TTC is greater than or equal to the first time period. If so, return to the data processing step and continue to obtain the above information through the perception module; if not, determine whether the collision time TTC is greater than or equal to the second time period. If so, control the warning light to flash and give a voice alarm. If the driver intervenes in time at this time, the control process is directly terminated. If the driver does not intervene at this time, return to the data processing step; if not, determine whether the collision time TTC is greater than or equal to the third time period. If not, determine whether the collision time TTC is within the first interval. If so, start the first strategy for braking; if not, determine whether the collision time TTC is within the second interval. If so, start the second strategy for braking; if not, determine whether the collision time TTC is within the third interval. If so, start the third strategy for braking; if not, determine whether the collision time TTC is within the third interval. If so, start the third strategy for braking; if not, determine whether the collision time is within the fourth interval. If so, start the fourth strategy for emergency obstacle avoidance.

[0173] In a preferred embodiment, when the current vehicle is in a wading state, if the collision time between the current vehicle and the obstacle is within a first interval, the first strategy is activated for braking. At this time, if the first strategy cannot effectively brake, when the collision time enters a second interval, the second strategy is activated for braking. At this time, if the second strategy still cannot effectively brake, the emergency strategy is directly activated to effectively avoid obstacles.

[0174] In a preferred embodiment, when the current vehicle is in a floating state, if the collision time between the current vehicle and the obstacle is within the first interval, the first strategy is activated for braking. At this time, if the first strategy cannot effectively brake, when the collision time enters the second interval, the second strategy is activated for braking. At this time, if the second strategy still cannot effectively brake, when the collision time enters the third interval, the third strategy is activated for braking. If the third strategy still cannot effectively brake, the emergency strategy is activated to effectively avoid obstacles.

[0175] In a preferred embodiment, the present application provides a Figure 6 The structural diagram of the perception module is shown in Figure 6 As shown, the perception module includes: a visual sub-module, a lidar sub-module, a millimeter-wave radar sub-module, an ultrasonic radar sub-module, a wading detection sub-module, and a vehicle information sub-module.

[0176] Among them, the visual submodule is used to obtain information such as the road conditions, pedestrians, vehicles, and water surface conditions in front of the vehicle; the laser radar submodule is used to collect point cloud data to accurately detect and locate obstacles above the water surface. The millimeter wave radar submodule is used to sense the operation of vehicles in a large range and enhance the long-distance perception ability of the vehicle. The ultrasonic radar submodule is used to detect underwater obstacle information and improve the vehicle's perception ability in wading or floating states. The vehicle information submodule is used to identify the specific operations of the current driver of the vehicle, such as throttle depth, steering wheel angle, and brake pedal depth information.

[0177] The embodiment of the present application provides a vehicle control method, the method comprising: determining the resistance of the current vehicle according to the speed, wading depth and cross-sectional area of ​​the current vehicle; calculating the collision time between the current vehicle and the obstacle according to the resistance of the current vehicle, the driving state information of the current vehicle and the underwater obstacle information; determining a target control strategy according to the collision time and the vehicle state of the current vehicle; and controlling the current vehicle to brake according to the target control strategy. The present application can effectively reduce the risk of underwater collision of the vehicle and improve the driving safety of the vehicle in underwater scenes by determining the corresponding target control strategy for braking according to the real-time situation of the underwater environment, combined with the underwater resistance factor, the vehicle state and the collision time between the vehicle and the obstacle.

[0178] In a second aspect of the present application, a vehicle control system is provided. Figure 7 As shown, including:

[0179] A first determination module 201 is used to determine the resistance experienced by the current vehicle according to the current vehicle speed, wading depth and cross-sectional area;

[0180] A calculation module 202, configured to calculate a collision time between the current vehicle and the obstacle according to the resistance experienced by the current vehicle, the driving state information of the current vehicle and the underwater obstacle information;

[0181] A second determination module 203 is used to determine a target control strategy according to the collision time and the vehicle state of the current vehicle;

[0182] The control module 204 is used to control the current vehicle to brake according to the target control strategy.

[0183] Optionally, the target control strategy is determined according to the collision time and the vehicle state of the current vehicle, and the second determination module 203 includes:

[0184] A first determination submodule is used to determine that the target control strategy is a first strategy when the collision time is in a first interval and the vehicle state is a wading state or a floating state, and the first strategy is to control the braking system of the current vehicle to brake each wheel of the current vehicle;

[0185] A second determination submodule is used to determine that the target control strategy is a second strategy when the collision time is in a second interval and the vehicle state is a wading state or a floating state, and the second strategy is to change the rear wheel posture angle of the current vehicle;

[0186] A third determination submodule, configured to determine that the target control strategy is a third strategy when the collision time is in a third interval and the vehicle state is a floating state, wherein the third strategy is to control the rear wheels of the current vehicle to reverse;

[0187] The fourth determination submodule is used to determine that the target control strategy is an emergency strategy when the collision time is in a fourth interval and the vehicle state is a wading state or a floating state. The emergency strategy is to control the current vehicle to change lanes according to the lane change curve in the current feasible area.

[0188] Optionally, the vehicle state is obtained based on the detected wading depth of the current vehicle and a driving mode pre-input by a driver, and the method further includes:

[0189] A judgment submodule, used for judging whether the current vehicle will collide with the obstacle when the current vehicle is in a floating state and the rear wheels of the current vehicle are controlled to change their posture angles;

[0190] The driving submodule is used to drive the rear wheels of the current vehicle to reverse by driving the motor when the current vehicle is about to collide with the obstacle.

[0191] Optionally, when the target control strategy is the first strategy, the controlling the current vehicle to brake according to the target control strategy, the control module 204 includes:

[0192] The first braking submodule is used to determine a first braking force of the braking system of the current vehicle based on the resistance-vehicle speed-wading depth curve when the current vehicle is in a wading state, and brake each wheel of the current vehicle based on the first braking force.

[0193] Optionally, when the target control strategy is the first strategy, the controlling the current vehicle to brake according to the target control strategy, the control module 204 includes:

[0194] The second braking submodule is used to control each motor of the current vehicle to stop providing driving torque and control the braking system of the current vehicle to brake each wheel of the current vehicle when the current vehicle is in a floating state.

[0195] Optionally, when the target control strategy is the second strategy, the current vehicle is controlled to brake according to the target control strategy, and the control module 204 includes:

[0196] An acquisition submodule, used to acquire a maximum steering angle of a rear wheel independent steering mechanism of the current vehicle;

[0197] The steering submodule is used to control the rear wheels of the current vehicle to steer according to the maximum steering angle based on the maximum steering angle to change the posture angle of the rear wheels, wherein the left rear wheel and the right rear wheel of the current vehicle steer in opposite directions.

[0198] Optionally, when the target control strategy is the emergency strategy, controlling the current vehicle to brake according to the target control strategy includes:

[0199] a fifth determining submodule, configured to determine the lane changing curve in the current feasible area according to the driving state information and the obstacle information;

[0200] The lane changing submodule is used to control the current vehicle to change lanes according to the lane changing curve.

[0201] Optionally, the controlling the current vehicle to change lanes according to the lane changing curve, the lane changing submodule includes:

[0202] An acquisition subunit, used to acquire a longitudinal speed error and a lateral speed error of the current vehicle;

[0203] a determination subunit, configured to determine a second braking force of a braking system of the current vehicle according to the longitudinal speed error;

[0204] A first calculation subunit, configured to calculate a steering angle of a front wheel of the current vehicle by using a PID algorithm according to the lateral error;

[0205] A second calculation subunit, configured to calculate a steering angle of a rear wheel of the current vehicle according to the steering angle of the front wheel;

[0206] The lane changing subunit is used to control the current vehicle to change lanes according to the second braking force, the steering angle of the front wheels, and the steering angle of the rear wheels.

[0207] Based on the same concept, a third aspect of an embodiment of the present application provides a vehicle, which includes the vehicle control system described in the second aspect of the present application, and / or executes the vehicle control method described in the first aspect of the present application.

[0208] Each embodiment in this specification focuses on the differences from other embodiments, and the same or similar parts between the embodiments can be referenced to each other.

[0209] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, devices, or computer program products. Therefore, the embodiments of the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the embodiments of the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0210] The embodiments of the present application are described with reference to the flowcharts and / or block diagrams of the methods, terminal devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing terminal device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminal device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0211] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing terminal device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured product including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0212] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal device so that a series of operating steps are executed on the computer or other programmable terminal device to produce a computer-implemented process, thereby providing instructions for executing on the computer or other programmable terminal device to implement the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0213] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present application.

[0214] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0215] The above is a detailed introduction to a vehicle control method, system and vehicle provided. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A vehicle control method, characterized in that: The method comprises: Determining the resistance experienced by the current vehicle according to the current vehicle speed, wading depth and cross-sectional area of ​​the vehicle; Calculating the collision time between the current vehicle and the obstacle according to the resistance experienced by the current vehicle, the driving state information of the current vehicle and the underwater obstacle information; Determining a target control strategy according to the collision time and the vehicle state of the current vehicle; Control the current vehicle to brake according to the target control strategy.

2. The vehicle control method according to claim 1, characterized in that: Determining a target control strategy according to the collision time and the vehicle state of the current vehicle includes: When the collision time is in the first interval and the vehicle state is a wading state or a floating state, determining that the target control strategy is a first strategy, wherein the first strategy is to control the braking system of the current vehicle to brake each wheel of the current vehicle; When the collision time is in the second interval and the vehicle state is a wading state or a floating state, determining that the target control strategy is a second strategy, and the second strategy is to change the rear wheel posture angle of the current vehicle; When the collision time is in the third interval and the vehicle state is in a floating state, determining that the target control strategy is a third strategy, and the third strategy is to control the rear wheels of the current vehicle to reverse; When the collision time is in the fourth interval and the vehicle state is a wading state or a floating state, the target control strategy is determined to be an emergency strategy, and the emergency strategy is to control the current vehicle to change lanes according to a lane change curve in a current feasible area.

3. The vehicle control method according to claim 2, characterized in that: The vehicle state is obtained based on the detected wading depth of the current vehicle and a driving mode pre-input by a driver, and the method further includes: When the current vehicle is in a floating state and the rear wheels of the current vehicle are controlled to change their posture angles, determining whether the current vehicle will collide with the obstacle; In the case that the current vehicle is about to collide with the obstacle, the rear wheels of the current vehicle are driven to reverse by a driving motor.

4. The vehicle control method according to claim 2, characterized in that: When the target control strategy is the first strategy, controlling the current vehicle to brake according to the target control strategy includes: When the current vehicle is in a wading state, a first braking force of a braking system of the current vehicle is determined based on the resistance-vehicle speed-wading depth curve, and each wheel of the current vehicle is braked based on the first braking force.

5. The vehicle control method according to claim 2, characterized in that: When the target control strategy is the first strategy, controlling the current vehicle to brake according to the target control strategy includes: When the current vehicle is in a floating state, each motor of the current vehicle is controlled to stop providing driving torque, and a braking system of the current vehicle is controlled to brake each wheel of the current vehicle.

6. The vehicle control method according to claim 2, characterized in that: When the target control strategy is the second strategy, controlling the current vehicle to brake according to the target control strategy includes: Obtaining a maximum steering angle of a rear wheel independent steering mechanism of the current vehicle; Based on the maximum steering angle, the rear wheels of the current vehicle are controlled to steer according to the maximum steering angle to change the posture angle of the rear wheels, wherein the left rear wheel and the right rear wheel of the current vehicle steer in opposite directions.

7. The vehicle control method according to claim 2, characterized in that: In the case where the target control strategy is the emergency strategy, controlling the current vehicle to brake according to the target control strategy includes: Determining the lane changing curve in the current feasible area according to the driving state information and the obstacle information; Control the current vehicle to change lanes according to the lane changing curve.

8. The vehicle control method according to claim 7, characterized in that: The controlling the current vehicle to change lanes according to the lane changing curve includes: Obtaining a longitudinal speed error and a lateral speed error of the current vehicle; determining a second braking force of a braking system of the current vehicle according to the longitudinal speed error; According to the lateral error, the steering angle of the front wheel of the current vehicle is calculated by a PID algorithm; Calculating the steering angle of the rear wheels of the current vehicle according to the steering angle of the front wheels; The current vehicle is controlled to change lanes according to the second braking force, the steering angle of the front wheels, and the steering angle of the rear wheels.

9. A vehicle control system, characterized in that: The system comprises: A first determination module, configured to determine the resistance experienced by the current vehicle according to the current vehicle speed, wading depth and cross-sectional area; A calculation module, used for calculating the collision time between the current vehicle and the obstacle according to the resistance suffered by the current vehicle, the driving state information of the current vehicle and the underwater obstacle information; A second determination module, configured to determine a target control strategy according to the collision time and the vehicle state of the current vehicle; A control module is used to control the current vehicle to brake according to the target control strategy.

10. A vehicle, characterized in that: The vehicle includes the vehicle control system according to claim 9, and / or executes the vehicle control method according to any one of claims 1-8.

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