Method and System for Determining Vehicle Body Dynamic Response Parameters

Abstract

The present invention provides a method and a system for determining vehicle body dynamic response parameters. The method includes: constructing a rotation matrix based on the installation position of an IMU and a preset rotation sequence of the IMU; determining a conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located based on the rotation matrix; determining a first corresponding relationship based on the conversion relationship, where the first corresponding relationship is the relationship between the acceleration of a position point to be measured on the vehicle body in the inertial coordinate system, the distance from the position point to be measured to the installation position of the IMU in the IMU coordinate system, and the speed detection value, and the speed detection value is the speed value detected by the IMU in the IMU coordinate system; determining the vehicle body dynamic response parameters based on the first corresponding relationship, and the vehicle body dynamic response parameters include: the vehicle body roll center and the vehicle body pitch center. It is used to solve the defect that high-cost configurations are required in the prior art when determining vehicle body dynamic response parameters, and to realize the identification and determination of vehicle body dynamic response parameters under a lower-cost configuration.

Description

Technical Field

[0001] The present invention relates to the technical field of dynamic response parameter measurement, and particularly to a method and system for determining vehicle body dynamic response parameters. Background Art

[0002] Once the parameters of a traditional vehicle suspension are selected, it is difficult to change them. Therefore, in the design process, an optimal compromise solution is usually sought to determine the parameters. That is, only under specific working conditions is the performance of the vehicle optimal. Once the working conditions change (for example: road surface changes, driving acceleration, braking, steering, etc.), the performance of the vehicle will deteriorate. This means that traditional suspensions are difficult to meet the requirements of both comfort and stability simultaneously, thus limiting the further improvement of vehicle performance.

[0003] Based on this, controllable suspensions have emerged. Through intelligent control, controllable suspensions can have different performances according to different road conditions, thereby coordinating the contradiction between ride comfort and stability. For example: semi-active suspensions belong to one type of controllable suspensions. Without changing the suspension stiffness, they can adjust the performance of the suspension by only changing the damping of the suspension. Therefore, they are also called damping controllable suspensions. Damping controllable suspensions have a relatively simple structure, low cost, and excellent performance, and have broad application prospects.

[0004] Controllable suspensions need to adjust their performance based on the positions of the roll center and pitch center of the vehicle body. Therefore, the accuracy of the position analysis of the roll center and pitch center directly affects the performance of controllable suspensions. Currently, for the identification and calibration of the roll center and pitch center, the main arrangement scheme is as Figure 1 shown. That is, on the vehicle body 1, the data detected by the height sensor 2 and the acceleration sensor 3 are respectively transmitted to the vehicle controller 5 based on the network 4, and then the vehicle controller 5 analyzes the data to achieve the identification and calibration of the roll center and pitch center. Finally, a control signal is generated based on the analysis result and transmitted to the suspension assembly 6 to achieve the adjustment of the suspension performance. However, as Figure 1 shown, this method requires installing 4 acceleration sensors on the vehicle body, which not only increases the configuration cost but also makes the difficulty of signal line layout increase. Summary of the Invention

[0005] The present invention provides a method and system for determining vehicle body dynamic response parameters to solve the defect in the prior art that high-cost configurations are required when determining vehicle body dynamic response parameters, and to achieve the identification and determination of vehicle body dynamic response parameters under a lower-cost configuration.

[0006] The present invention also provides a method for determining vehicle body dynamic response parameters, including:

[0007] Construct a rotation matrix based on the installation position of the IMU and the preset rotation order of the IMU;

[0008] Based on the rotation matrix, determine the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located;

[0009] Based on the conversion relationship, determine a first correspondence, where the first correspondence is the relationship between the acceleration of the position point to be measured on the vehicle body in the inertial coordinate system, the distance from the position point to be measured to the installation position of the IMU in the IMU coordinate system, and the speed detection value, and the speed detection value is the speed value detected by the IMU in the IMU coordinate system;

[0010] Based on the first correspondence, determine the dynamic response parameters of the vehicle body, where the dynamic response parameters include: the roll center of the vehicle body and the pitch center of the vehicle body.

[0011] According to the method for determining the dynamic response parameters of the vehicle body according to the present invention, the determining the dynamic response parameters of the vehicle body based on the first correspondence includes:

[0012] Based on the acceleration at the dynamic response parameters of the vehicle body and the first correspondence, determine a second correspondence, where the second correspondence is the relationship between the position of the dynamic response parameters of the vehicle body on the vehicle body and the installation position of the IMU;

[0013] Based on the second correspondence and the installation position of the IMU, determine the dynamic response parameters of the vehicle body.

[0014] According to the method for determining the dynamic response parameters of the vehicle body according to the present invention, the determining the dynamic response parameters of the vehicle body based on the first correspondence further includes:

[0015] Based on the acceleration along the vehicle body width direction at the roll center of the vehicle body in the inertial coordinate system, determine the vertical distance from the roll center of the vehicle body to the installation position of the IMU;

[0016] Based on the vertical distance from the roll center of the vehicle body to the installation position of the IMU and the installation position of the IMU, determine the roll center of the vehicle body.

[0017] According to the method for determining the dynamic response parameters of the vehicle body according to the present invention, the determining the dynamic response parameters of the vehicle body based on the first correspondence further includes:

[0018] Based on the acceleration along the vehicle body length direction at the pitch center of the vehicle body in the inertial coordinate system, determine the longitudinal distance from the pitch center of the vehicle body to the installation position of the IMU along the vehicle body length direction;

[0019] Based on the acceleration in the vehicle body height direction at the vehicle body pitch center in the inertial coordinate system, determine the vertical distance from the vehicle body pitch center to the installation position of the IMU;

[0020] Based on the vertical distance from the vehicle body pitch center to the installation position of the IMU, in the vehicle body length direction, the longitudinal distance from the vehicle body pitch center to the installation position of the IMU, and the installation position of the IMU, determine the vehicle body pitch center.

[0021] According to the method for determining the vehicle body dynamic response parameters of the present invention, the construction of the rotation matrix based on the installation position of the IMU and the preset rotation order of the IMU includes:

[0022] Based on the installation position of the IMU that makes the IMU coaxial with the vehicle body, and the preset rotation order of successively rotating around the yaw angle θ, pitch angle β, and roll angle γ, construct the rotation matrix; the rotation matrix is:

[0023]

[0024] where A represents the rotation matrix.

[0025] According to the method for determining the vehicle body dynamic response parameters of the present invention, the determination of the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located based on the rotation matrix includes:

[0026] According to a preset first formula, based on the rotation matrix, determine the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located; the preset first formula is:

[0027]

[0028]

[0029] where represents the acceleration of the point to be measured in the inertial coordinate system; a represents the linear acceleration; α represents the angular acceleration; ω represents the angular velocity; x i 、y i and z i respectively represent the distances from the point to be measured in the IMU coordinate system to the installation position of the IMU in the x-axis, y-axis, and z-axis directions; the superscript i represents the IMU coordinate system; the subscripts x, y, and z respectively represent the directions along the x-axis, y-axis, and z-axis of the coordinate system.

[0030] The method for determining the vehicle body dynamic response parameters according to the present invention, based on the conversion relationship, determining the first correspondence relationship, includes:

[0031] Based on the conversion relationship, determining the first correspondence relationship according to a preset second formula; the preset second formula is:

[0032]

[0033] Wherein, the subscript p represents the position point P on the vehicle body.

[0034] The present invention also provides a system for determining vehicle body dynamic response parameters, including:

[0035] A construction module, configured to construct a rotation matrix based on the installation position of the IMU and a preset rotation sequence of the IMU;

[0036] A first processing module, configured to determine the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located based on the rotation matrix;

[0037] A second processing module, configured to determine a first correspondence relationship based on the conversion relationship, where the first correspondence relationship is the relationship between the acceleration of a to-be-detected position point on the vehicle body in the inertial coordinate system, the distance from the to-be-detected position point to the installation position of the IMU in the IMU coordinate system, and the speed detection value, and the speed detection value is the speed value detected by the IMU in the IMU coordinate system;

[0038] A third processing module, configured to determine the dynamic response parameters of the vehicle body based on the first correspondence relationship, where the dynamic response parameters include: the vehicle body roll center and the vehicle body pitch center.

[0039] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor, where when the processor executes the program, it implements the method for determining vehicle body dynamic response parameters as described in any one of the above.

[0040] The present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the method for determining vehicle body dynamic response parameters as described in any one of the above.

[0041] A method and system for determining vehicle body dynamic response parameters provided by the present invention first constructs a rotation matrix based on the installation position of an IMU and a preset rotation sequence of the IMU, then determines the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system based on the rotation matrix, and further determines the relationship between the acceleration of the position point to be measured on the vehicle body in the inertial coordinate system, the distance from the position point to be measured in the IMU coordinate system to the installation position of the IMU, and the speed detection value detected by the IMU. Finally, based on the relationship between the acceleration of the position point to be measured in the inertial coordinate system, the installation position of the IMU in the IMU coordinate system, and the data detected by the IMU, the vehicle body dynamic response parameters can be determined. Thus, the identification and determination of vehicle body dynamic response parameters are realized by using the IMU arranged on the vehicle body. Compared with the existing method of obtaining vehicle body dynamic response parameters by arranging multiple acceleration sensors on the vehicle body, the cost of equipment arrangement is greatly reduced, and at the same time, the difficulty of arranging signal lines is also reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0043] Figure 1 It is a schematic diagram of the arrangement structure of acceleration sensors on the vehicle body when identifying and determining vehicle body dynamic response parameters in the prior art;

[0044] Figure 2 It is a schematic flow chart of a method for determining vehicle body dynamic response parameters provided by an embodiment of the present invention;

[0045] Figure 3 It is a schematic diagram of the relationship between the inertial coordinate system and the IMU coordinate system;

[0046] Figure 4 It is a schematic diagram of the arrangement of the IMU and acceleration sensors on the vehicle body provided by an embodiment of the present invention;

[0047] Figure 5 It is a position relationship diagram of the vehicle body roll center provided by an embodiment of the present invention;

[0048] Figure 6 It is a schematic diagram of the distance relationship between the arrangement position of an IMU and the front and rear axles of the vehicle provided by an embodiment of the present invention;

[0049] Figure 7It is a schematic structural diagram of a structure in which an IMU is coaxially arranged with a vehicle body provided by an embodiment of the present invention;

[0050] Figure 8 It is a schematic structural diagram of a system for determining vehicle body dynamic response parameters provided by an embodiment of the present invention;

[0051] Figure 9 Schematic structural diagram of an electronic device provided by the present invention;

[0052] Reference numerals:

[0053] 1: Vehicle body; 2: Height sensor; 3: Acceleration sensor; 4: Network; 5: Vehicle controller; 6: Suspension assembly; 7: IMU. Detailed implementation manners

[0054] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings in the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without making creative efforts shall fall within the protection scope of the present invention.

[0055] First, for the convenience of understanding the method for determining vehicle body dynamic response parameters provided by the embodiments of the present invention, the meanings of technical terms involved in the embodiments of the present invention will be described first:

[0056] Inertial measurement unit (IMU): Usually includes three sensors, namely an accelerometer, a gyroscope and a magnetometer, mainly used to detect and measure acceleration and rotational motion.

[0057] Rotation matrix: A matrix that changes the direction of a vector but not its magnitude when multiplying a vector.

[0058] Inertial coordinate system: It is generated to simplify the conversion from the world coordinate system to the object coordinate system. The origin of the inertial coordinate system coincides with the origin of the object coordinate system, and the axes of the inertial coordinate system are parallel to the axes of the world coordinate system. After introducing the inertial coordinate system, the conversion of the object coordinate system to the inertial coordinate system only requires rotation.

[0059] IMU coordinate system: The origin of the coordinate is at the origin of the gyroscope and the accelerometer, and the directions of the x, y, and z axes are respectively parallel to the corresponding axial directions of the gyroscope and the accelerometer.

[0060] Next, in combination with Figures 2 to 7A method for determining vehicle body dynamic response parameters of the present invention is executed based on a vehicle controller or a combination of software and / or hardware therein. The controller may be a vehicle controller already arranged on the vehicle or a separately arranged controller. Among them, as Figure 2 shown, the method for determining vehicle body dynamic response parameters provided by the embodiment of the present invention includes the following steps:

[0061] 101. Construct a rotation matrix based on the installation position of the IMU and the preset rotation order of the IMU;

[0062] It can be understood that, as Figure 3 shown, OXYZ is an absolute coordinate system fixed to the ground; O i X m Y m Z m is an inertial coordinate system with the origin coinciding with the IMU installation position and the three-axis directions being the same as those of the absolute coordinate system; O i X i Y i Z i is a coordinate system fixed to the IMU, that is, the IMU coordinate system, and the three-axis directions thereof are the acceleration directions directly measured by the IMU. It can be seen that the origin of the inertial coordinate system coincides with the origin of the IMU coordinate system, and rotating the IMU coordinate system can be converted into the inertial coordinate system. However, the velocity detection values detected by the IMU are the detection values corresponding to the three-axis directions of the IMU coordinate system respectively, which are rotations around the yaw angle, rotations around the pitch angle, and rotations around the roll angle relative to the vehicle body. Although for the driving of the vehicle, the rotations of the IMU along the three-axis directions occur simultaneously, through the preset rotation order, the conversion from the IMU coordinate system to the inertial coordinate system can be simplified, that is, the IMU coordinate system first rotates around the direction of the first axis, then rotates along the direction of the second axis, and finally rotates around the direction of the third axis.

[0063] Specifically, the preset rotation order can be: first rotate around the yaw angle, then rotate around the pitch angle, and finally rotate around the roll angle; or the preset rotation order can be: first rotate around the pitch angle, then rotate around the yaw angle, and finally rotate around the roll angle, etc., and no specific limitation is required here.

[0064] More specifically, the expression form of the rotation matrix is also related to the installation position of the IMU. Therefore, based on the installation position of the IMU and the preset rotation order of the IMU, the specific expression form of the rotation matrix can be determined, that is, the construction of the rotation matrix is completed.

[0065] 102. Determine the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located based on the rotation matrix;

[0066] It can be understood that in the method for determining the vehicle body dynamic response parameters provided by the embodiments of the present invention, the origin of the inertial coordinate system coincides with the origin of the IMU coordinate system. By rotating the IMU coordinate system through a rotation matrix, the inertial coordinate system can be obtained.

[0067] 103. Based on the conversion relationship, determine a first correspondence relationship, where the first correspondence relationship is the relationship between the acceleration of the position point to be measured on the vehicle body in the inertial coordinate system, the distance from the position point to be measured to the installation position of the IMU in the IMU coordinate system, and the speed detection value, and the speed detection value is the speed value detected by the IMU in the IMU coordinate system;

[0068] Specifically, taking Figure 3 the position point P to be measured shown as an example, after determining the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system, according to the conversion relationship, the acceleration of point P in the inertial coordinate system can be expressed by the distance from point P to the installation position of the IMU in the IMU coordinate system and the speed detection value detected by the IMU.

[0069] 104. Based on the first correspondence relationship, determine the dynamic response parameters of the vehicle body, and the dynamic response parameters include: the vehicle body roll center and the vehicle body pitch center.

[0070] It can be understood that regarding a vehicle, strictly speaking, the vehicle body, when discussing its dynamic response, generally three key attributes are commonly used to characterize its motion, namely the rotations around the X, Y, and Z axes passing through the center of mass, which respectively refer to the roll around the X axis, the pitch around the Y axis, and the yaw around the Z axis.

[0071] Furthermore, for yaw, it is an actively required response. Generally speaking, when turning the steering wheel, the vehicle turns and the yaw changes. Therefore, for the yaw of the vehicle, the performance of the suspension does not need to be adjusted. For pitch and roll, when the vehicle turns, due to the torque effect of the vehicle body centrifugal force on the wheel contact point, the vehicle body will tilt around the vehicle longitudinal axis, that is, roll. The instantaneous rotation center of the vehicle body relative to the ground when the vehicle body rolls is the vehicle body roll center; when the vehicle brakes or accelerates, it causes the front of the vehicle to sink or rise, which is called vehicle body pitch. The center point around which the vehicle body pitches is the vehicle body pitch center. Therefore, the vehicle body roll center and the vehicle body pitch center are specific position points to be measured on the vehicle body. And when the vehicle body roll center and the pitch center cannot be determined, or the determination is not accurate enough, the suspension performance cannot be adjusted well, thereby affecting both the stability and comfort of the vehicle.

[0072] Specifically, for the body roll center, the acceleration along the body width, that is, the lateral direction, is 0; and for the body pitch center, the acceleration along the body length and the height direction is also 0. Therefore, according to the conversion relationship, the acceleration of point P in the inertial coordinate system is represented by the distance between point P and the installation position of the IMU in the IMU coordinate system, and the speed detection value detected by the IMU, and on the basis that the acceleration value of the body pitch center or the body roll center can be determined, the relationship between the body pitch center or the body roll center and the installation position of the IMU can be obtained, so as to further determine the position of the body pitch center or the body roll center, that is, the body dynamic response parameter.

[0073] More specifically, the method for determining the vehicle body dynamic response parameters provided by the embodiment of the present invention requires the installation position and detection data of the IMU to achieve the determination of the vehicle body dynamic response parameters. Therefore, by arranging an IMU or directly using the IMU already arranged on the vehicle body, the vehicle body dynamic response parameters can be determined. Figure 4 As shown in the figure, the square points indicate the installation positions of the acceleration sensors on the vehicle body, and the IMU can generally be set as follows: Figure 4 Any position indicated by the dot in the middle, for example, is set on the vehicle body near the left wheel, near the front axle, etc. It can be understood that Figure 4 In order to explain the location of the acceleration sensor and IMU on the vehicle body, the location points are marked on the surface of the vehicle body. Figure 4 The inside of the vehicle body after the marked position is viewed through. It can be seen that compared with the existing method of obtaining the vehicle body dynamic response parameters by arranging multiple acceleration sensors on the vehicle body, the method for determining the vehicle body dynamic response parameters provided by the embodiment of the present invention greatly reduces the cost of equipment arrangement and also reduces the difficulty of arranging signal lines.

[0074] As an embodiment of the present invention, determining the dynamic response parameter of the vehicle body based on the first corresponding relationship includes:

[0075] Determine a second corresponding relationship based on the acceleration at the vehicle body dynamic response parameter and the first corresponding relationship, wherein the second corresponding relationship is a relationship between a position of the vehicle body dynamic response parameter on the vehicle body and an installation position of the IMU;

[0076] Based on the second corresponding relationship and the installation position of the IMU, the vehicle body dynamic response parameter is determined.

[0077] Specifically, for the body roll center, the lateral acceleration of the vehicle body is 0; for the body pitch center, the accelerations in the vehicle body length and height directions are 0, that is, for the body roll center and the body pitch center in the inertial coordinate system, there are specific directions with an acceleration of 0. Therefore, after expressing the acceleration of point P in the inertial coordinate system according to the conversion relationship using the distance between point P and the installation position of the IMU in the IMU coordinate system and the speed detection value detected by the IMU, in the specific direction where the acceleration of the body pitch center or the body roll center is 0, the relationship between the distances of the body pitch center or the body roll center from the installation position of the IMU in the IMU coordinate system can be obtained, that is, the second corresponding relationship can be obtained. At the same time, the installation position of the IMU is known. Therefore, after determining the relationship between the distances of the body pitch center and the body roll center from the installation position of the IMU, the positions of the body roll center and the body pitch center can be further determined, that is, the vehicle body dynamic response parameters.

[0078] As an embodiment of the present invention, further comprising, based on the first corresponding relationship, determining the vehicle body dynamic response parameters:

[0079] Based on the acceleration in the vehicle body width direction at the body roll center in the inertial coordinate system, determining the vertical distance between the body roll center and the installation position of the IMU;

[0080] Based on the vertical distance between the body roll center and the installation position of the IMU, and the installation position of the IMU, determining the body roll center.

[0081] It can be understood that when the vehicle rolls, there should be a roll center in each different vertical transverse section. By connecting these roll centers, a roll center axis for suspension performance adjustment can be obtained.

[0082] Specifically, based on the relationship between the acceleration of a position point in the inertial coordinate system and the distance between this position point and the installation position of the IMU in the IMU coordinate system, and the speed detection value detected by the IMU, for the body roll center, the roll center on a specified vertical transverse section in the vehicle body longitudinal direction can be determined. Therefore, before determining the body roll center, it is necessary to preset which vertical transverse section the body roll center is on. At the same time, in order to obtain the roll center axis, a method of determining at least two body roll centers on the vehicle body can be selected, thereby reducing the data processing amount and improving the efficiency.

[0083] More specifically, it is preferable to determine the positions of two body roll centers on the vehicle body to further simplify the data processing. For example: in order to improve the convenience of determining the position information of the to-be-determined body roll center in the vehicle body length direction based on the installation position of the IMU, it is possible to choose to determine respectively, such asFigure 5 Two body roll centers located at the front and rear axles of the vehicle body as shown in Figure 5 The center points shown by the dots are the body roll centers, and the line connecting the two is the roll center axis). Specifically, as shown in Figure 6 shown, when the positions of the front and rear axles of the vehicle body are known, the distances from the installation position of the IMU to the front and rear axles can be conveniently obtained: and and the distance from the longitudinal central axis of the vehicle body After that, based on the relationship between the acceleration of the position point in the inertial coordinate system and the distance between the position point and the installation position of the IMU in the IMU coordinate system, as well as the speed detection value detected by the IMU, after obtaining the vertical distances from the two body roll centers at the front and rear axles of the vehicle body to the installation position of the IMU, based on the vertical distances from the two body roll centers at the front and rear axles of the vehicle body to the installation position of the IMU, and the installation position of the IMU, the positions of the two body roll centers in the vehicle body along the height direction can be determined, so as to further obtain the roll center axis to control the performance adjustment of the vehicle suspension.

[0084] As an embodiment of the present invention, the determining the body dynamic response parameters based on the first correspondence further includes:

[0085] Based on the acceleration along the length direction of the vehicle body at the body pitch center in the inertial coordinate system, determining the longitudinal distance from the body pitch center to the installation position of the IMU along the length direction of the vehicle body;

[0086] Based on the acceleration along the height direction of the vehicle body at the body pitch center in the inertial coordinate system, determining the vertical distance from the body pitch center to the installation position of the IMU;

[0087] Based on the vertical distance from the body pitch center to the installation position of the IMU, the longitudinal distance from the body pitch center to the installation position of the IMU along the length direction of the vehicle body, and the installation position of the IMU, determining the body pitch center.

[0088] Specifically, when the vehicle is driving at a constant speed and pitching, since there is no acceleration or deceleration of the vehicle, the acceleration along the length direction of the vehicle body is 0. At the same time, because the pitch center is the center of the circle based on which the vehicle body pitches, that is, rotates at a certain angle along the height direction of the vehicle body, the acceleration along the height direction of the vehicle body is also 0.

[0089] After determining the acceleration of the vehicle body in the vehicle body length direction and the height direction, based on the acceleration of the position point in the inertial coordinate system, the distance between the position point and the installation position of the IMU in the IMU coordinate system, and the relationship between the speed detection value detected by the IMU, the vertical distance from the pitch center of the vehicle body to the installation position of the IMU and the longitudinal distance from the pitch center of the vehicle body to the installation position of the IMU in the vehicle body length direction can be determined respectively. Further, when the installation position of the IMU is known, the specific position of the pitch center on the vehicle body can be determined.

[0090] As an embodiment of the present invention, the constructing a rotation matrix based on the installation position of the IMU and a preset rotation order of the IMU includes:

[0091] Based on the installation position of the IMU that makes the IMU coaxial with the vehicle body and the preset rotation order of sequentially rotating around the yaw angle θ, the pitch angle β, and the roll angle γ, constructing the rotation matrix; the rotation matrix is:

[0092]

[0093] where A represents the rotation matrix.

[0094] Specifically, as Figure 7 shown, on the vehicle body 1, by respectively transmitting the data detected by the height sensor 2 and the IMU 7 to the vehicle controller 5 based on the network 4, and then analyzing the data by the vehicle controller 5, the identification and calibration of the roll center and the pitch center are realized. Finally, a control signal is generated based on the analysis result and transmitted to the suspension assembly 6 to realize the adjustment of the suspension performance. By arranging the IMU coaxially with the vehicle body, on the one hand, it is convenient for calculation, simplifies the calibration procedure of the IMU, and improves the calibration efficiency. On the other hand, since the detection data given by the IMU along the axial direction is usually more accurate, arranging the IMU coaxially with the vehicle body can improve the accuracy of the obtained roll center and pitch center of the vehicle body.

[0095] As an embodiment of the present invention, the determining the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located based on the rotation matrix includes:

[0096] According to a preset first formula, based on the rotation matrix, determining the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located; the preset first formula is:

[0097]

[0098]

[0099] Among them, represents the acceleration of the position point to be measured in the inertial coordinate system; a represents the linear acceleration; α represents the angular acceleration; ω represents the angular velocity; x i , y i and z i respectively represent the distances from the position point to be measured in the IMU coordinate system to the installation position of the IMU in the x-axis, y-axis, and z-axis directions; the superscript i represents the IMU coordinate system; the subscripts x, y, and z respectively represent the directions along the x-axis, y-axis, and z-axis of the coordinate system.

[0100] It can be understood that by rotating the acceleration of the position point to be measured in the IMU coordinate system, the acceleration of the position point to be measured in the inertial coordinate system can be obtained.

[0101] Specifically, during the driving process of the vehicle, there are rotations along the height direction and the lateral direction due to roll or pitch. Therefore, the acceleration of the vehicle body should be rotated based on the translational acceleration, tangential acceleration, and centripetal acceleration respectively. Based on this, through the speed value detected by the IMU and the distance between the position point to be measured and the installation position of the IMU in the IMU coordinate system, the acceleration of the position point to be measured in the IMU coordinate system can be obtained, and then after rotation, the acceleration of the position point to be measured in the inertial coordinate system can be obtained, that is, as shown in Formula 2, where and respectively represent the translational accelerations along the three axes of the IMU coordinate system, and respectively represent the tangential accelerations along the three axes of the IMU coordinate system; while and respectively represent the centripetal accelerations along the three axes of the IMU coordinate system.

[0102] As an embodiment of the present invention, the determining the first correspondence relationship based on the conversion relationship includes:

[0103] Determining the first correspondence relationship based on the conversion relationship according to a preset second formula; the preset second formula is:

[0104]

[0105] where the subscript p represents the position point P on the vehicle body.

[0106] Specifically, according to the rigid body hypothesis of theoretical mechanics, it can be known that the angular velocity and angular acceleration of any position point to be measured along the same direction are equal. Therefore, the six kinematic information of point P can be obtained as:

[0107]

[0108] More specifically, when determining the body roll center, a yp = 0. At the same time, to determine the body roll centers of the front and rear axles as shown in Figure 5 and taking the installation position of the IMU as shown in Figure 6 as an example, from Equation 4, we can obtain:

[0109]

[0110] Thus, through Equation 5, the vertical distances from the body roll centers of the front and rear axles to the installation position of the IMU can be obtained. and

[0111]

[0112] Furthermore, the body roll center axis of the whole vehicle can be obtained.

[0113] Similarly, when determining the body pitch center, a xp = a zp = 0. At the same time, assuming that there is at the pitch center, then from Equation 4, we can obtain:

[0114]

[0115] Furthermore, by solving Equation 7, the body pitch center can be obtained.

[0116] Next, in combination with Figure 8 a system for determining body dynamic response parameters provided by the present invention will be described. The system for determining body dynamic response parameters described below can be correspondingly referred to the method for determining body dynamic response parameters described above.

[0117] As shown in Figure 8 , the present invention also provides a system for determining body dynamic response parameters, including: a construction module 810, a first processing module 820, a second processing module 830, and a third processing module 840; wherein,

[0118] The construction module 810 is configured to construct a rotation matrix based on the installation position of the IMU and a preset rotation sequence of the IMU;

[0119] The first processing module 820 is configured to determine the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located based on the rotation matrix;

[0120] The second processing module 830 is configured to determine a first correspondence relationship based on the conversion relationship, where the first correspondence relationship is the relationship between the acceleration of the position point to be measured on the vehicle body in the inertial coordinate system, the distance between the position point to be measured and the installation position of the IMU in the IMU coordinate system, and the speed detection value, and the speed detection value is the speed value detected by the IMU in the IMU coordinate system;

[0121] The third processing module 840 is configured to determine the dynamic response parameters of the vehicle body based on the first correspondence relationship, where the dynamic response parameters include: the roll center of the vehicle body and the pitch center of the vehicle body.

[0122] The system for determining the dynamic response parameters of the vehicle body provided by the embodiments of the present invention first constructs a rotation matrix based on the installation position of the IMU and the preset rotation order of the IMU, then determines the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located based on the rotation matrix, and further determines the relationship between the acceleration of the position point to be measured on the vehicle body in the inertial coordinate system and the distance between the position point to be measured and the installation position of the IMU in the IMU coordinate system and the speed detection value detected by the IMU based on the conversion relationship of the coordinate systems. Finally, based on the relationship between the acceleration of the position point to be measured in the inertial coordinate system and the installation position of the IMU in the IMU coordinate system and the data detected by the IMU, the dynamic response parameters of the vehicle body can be determined. Thus, the identification and determination of the dynamic response parameters of the vehicle body are realized by using the IMU arranged on the vehicle body. Compared with the existing method of obtaining the dynamic response parameters of the vehicle body by arranging multiple acceleration sensors on the vehicle body, the cost of equipment arrangement is greatly reduced, and at the same time, the difficulty of arranging signal lines is also reduced.

[0123] Preferably, the third processing module is specifically configured to determine a second correspondence relationship based on the acceleration at the dynamic response parameter of the vehicle body and the first correspondence relationship, where the second correspondence relationship is the relationship between the position of the dynamic response parameter of the vehicle body on the vehicle body and the installation position of the IMU; and determine the dynamic response parameter of the vehicle body based on the second correspondence relationship and the installation position of the IMU.

[0124] Preferably, the third processing module is further configured to determine the vertical distance between the roll center of the vehicle body and the installation position of the IMU based on the acceleration along the vehicle body width direction at the roll center of the vehicle body in the inertial coordinate system; and determine the roll center of the vehicle body based on the vertical distance between the roll center of the vehicle body and the installation position of the IMU and the installation position of the IMU.

[0125] Preferably, the third processing module is further configured to determine a longitudinal distance between the vehicle body pitch center and the installation position of the IMU along the vehicle body length direction based on the acceleration at the vehicle body pitch center along the vehicle body length direction in the inertial coordinate system; determine a vertical distance between the vehicle body pitch center and the installation position of the IMU based on the acceleration at the vehicle body pitch center along the vehicle body height direction in the inertial coordinate system; and determine the vehicle body pitch center based on the vertical distance between the vehicle body pitch center and the installation position of the IMU, the longitudinal distance between the vehicle body pitch center and the installation position of the IMU along the vehicle body length direction, and the installation position of the IMU.

[0126] Preferably, the construction module is specifically configured to construct the rotation matrix based on the installation position of the IMU that makes the IMU coaxial with the vehicle body and the preset rotation sequence that sequentially rotates around the yaw angle θ, pitch angle β, and roll angle γ; the rotation matrix is as shown in Formula 1 in the above embodiment.

[0127] Preferably, the first processing module is specifically configured to determine the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located based on the rotation matrix according to a preset first formula; the preset first formula is as shown in Formula 2 in the above embodiment.

[0128] Preferably, the second processing module is specifically configured to determine a first correspondence based on the conversion relationship according to a preset second formula; the preset second formula is as shown in Formula 3 in the above embodiment.

[0129] Figure 9 An example of a schematic physical structure diagram of an electronic device is shown in Figure 9As shown in the figure, the electronic device may include: a processor 910, a communications interface 920, a memory 930, and a communication bus 940. Among them, the processor 910, the communications interface 920, and the memory 930 complete communication with each other through the communication bus 940. The processor 910 uses the memory 930 to execute logical instructions to perform a method for determining vehicle body dynamic response parameters. The method includes: constructing a rotation matrix based on the installation position of the IMU and a preset rotation order of the IMU; determining a conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located based on the rotation matrix; determining a first correspondence based on the conversion relationship, where the first correspondence is the relationship between the acceleration of a position point to be measured on the vehicle body in the inertial coordinate system, the distance from the position point to be measured to the installation position of the IMU in the IMU coordinate system, and the speed detection value, and the speed detection value is the speed value detected by the IMU in the IMU coordinate system; determining the dynamic response parameters of the vehicle body based on the first correspondence, where the dynamic response parameters include: the vehicle body roll center and the vehicle body pitch center.

[0130] In addition, when the above-mentioned memory 930 logical instructions are implemented in the form of a software functional unit and sold or used as an independent product, they can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0131] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the method for determining the vehicle body dynamic response parameters provided by the above-mentioned various methods. The method includes: constructing a rotation matrix based on the installation position of the IMU and the preset rotation order of the IMU; determining the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located based on the rotation matrix; determining a first correspondence based on the conversion relationship, where the first correspondence is the relationship between the acceleration of the position point to be measured on the vehicle body in the inertial coordinate system, the distance between the position point to be measured and the installation position of the IMU in the IMU coordinate system, and the speed detection value, and the speed detection value is the speed value detected by the IMU in the IMU coordinate system; determining the dynamic response parameters of the vehicle body based on the first correspondence, and the dynamic response parameters include: the vehicle body roll center and the vehicle body pitch center.

[0132] In another aspect, the present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements the method for determining the vehicle body dynamic response parameters provided by the above-mentioned various methods. The method includes: constructing a rotation matrix based on the installation position of the IMU and the preset rotation order of the IMU; determining the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located based on the rotation matrix; determining a first correspondence based on the conversion relationship, where the first correspondence is the relationship between the acceleration of the position point to be measured on the vehicle body in the inertial coordinate system, the distance between the position point to be measured and the installation position of the IMU in the IMU coordinate system, and the speed detection value, and the speed detection value is the speed value detected by the IMU in the IMU coordinate system; determining the dynamic response parameters of the vehicle body based on the first correspondence, and the dynamic response parameters include: the vehicle body roll center and the vehicle body pitch center.

[0133] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. A person of ordinary skill in the art can understand and implement it without creative labor.

[0134] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on such an understanding, the essence of the above technical solution, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0135] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. And these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for determining vehicle body dynamic response parameters, characterized in that, Including: Construct a rotation matrix based on the installation position of the IMU and a preset rotation order of the IMU; Determine a conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located based on the rotation matrix; Determine a first correspondence based on the conversion relationship, where the first correspondence is the relationship between the acceleration of a position point to be measured on the vehicle body in the inertial coordinate system, the distance from the position point to be measured to the installation position of the IMU in the IMU coordinate system, and a speed detection value, and the speed detection value is the speed value detected by the IMU in the IMU coordinate system; Determine the dynamic response parameters of the vehicle body based on the first correspondence, where the dynamic response parameters include: the roll center of the vehicle body and the pitch center of the vehicle body; The determining the dynamic response parameters of the vehicle body based on the first correspondence includes: Determine a second correspondence based on the acceleration at the dynamic response parameters of the vehicle body and the first correspondence, where the second correspondence is the relationship between the position of the dynamic response parameters of the vehicle body on the vehicle body and the installation position of the IMU; Determine the dynamic response parameters of the vehicle body based on the second correspondence and the installation position of the IMU.

2. The method for determining the vehicle body dynamic response parameters according to claim 1, wherein The determining the dynamic response parameters of the vehicle body based on the first correspondence further includes: Determine the vertical distance from the roll center of the vehicle body to the installation position of the IMU based on the acceleration along the vehicle body width direction at the roll center of the vehicle body in the inertial coordinate system; Determine the roll center of the vehicle body based on the vertical distance from the roll center of the vehicle body to the installation position of the IMU and the installation position of the IMU.

3. The method for determining the vehicle body dynamic response parameters according to claim 1, characterized in that The determining the dynamic response parameters of the vehicle body based on the first correspondence further includes: Determine the longitudinal distance from the pitch center of the vehicle body to the installation position of the IMU along the vehicle body length direction based on the acceleration along the vehicle body length direction at the pitch center of the vehicle body in the inertial coordinate system; Determine the vertical distance from the pitch center of the vehicle body to the installation position of the IMU based on the acceleration along the vehicle body height direction at the pitch center of the vehicle body in the inertial coordinate system; Determine the pitch center of the vehicle body based on the vertical distance from the pitch center of the vehicle body to the installation position of the IMU, the longitudinal distance from the pitch center of the vehicle body to the installation position of the IMU along the vehicle body length direction, and the installation position of the IMU.

4. The method for determining the vehicle body dynamic response parameters according to claim 1, characterized in that The constructing a rotation matrix based on the installation position of the IMU and a preset rotation order of the IMU includes: Construct the rotation matrix based on the installation position of the IMU that makes the IMU coaxial with the vehicle body and the preset rotation order of sequentially rotating around the yaw angle θ, pitch angle β, and roll angle γ; the rotation matrix is: Where A represents the rotation matrix.

5. The method for determining the vehicle body dynamic response parameters according to claim 4, characterized in that The determining a conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located based on the rotation matrix includes: Based on the preset first formula and the rotation matrix, determine the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located; the preset first formula is: Among them, represents the acceleration of the position point to be measured in the inertial coordinate system; a represents the linear acceleration; α represents the angular acceleration; ω represents the angular velocity; x i , y i and z i respectively represent the distances from the installation position of the IMU to the position point to be measured in the x-axis, y-axis, and z-axis directions in the IMU coordinate system; the superscript i represents the IMU coordinate system; the subscripts x, y, and z respectively represent the directions along the x-axis, y-axis, and z-axis of the coordinate system.

6. The method for determining the vehicle body dynamic response parameters according to claim 5, characterized in that The determining the first correspondence based on the conversion relationship includes: Based on the conversion relationship, determine the first correspondence according to the preset second formula; the preset second formula is: Among them, the subscript p represents the position point P on the vehicle body.

7. A system for determining vehicle body dynamic response parameters, characterized in that, It includes: A construction module for constructing a rotation matrix based on the installation position of the IMU and the preset rotation sequence of the IMU; A first processing module for determining the conversion relationship between the inertial coordinate system where the IMU is located and the IMU coordinate system where the IMU is located based on the rotation matrix; A second processing module for determining a first correspondence based on the conversion relationship, where the first correspondence is the relationship between the acceleration of the position point to be measured on the vehicle body in the inertial coordinate system, the distance from the position point to be measured to the installation position of the IMU in the IMU coordinate system, and the speed detection value, and the speed detection value is the speed value detected by the IMU in the IMU coordinate system; A third processing module for determining the dynamic response parameters of the vehicle body based on the first correspondence, where the dynamic response parameters include: the roll center of the vehicle body and the pitch center of the vehicle body; The determining the dynamic response parameters of the vehicle body based on the first correspondence includes: Based on the acceleration at the dynamic response parameters of the vehicle body and the first correspondence, determine a second correspondence, where the second correspondence is the relationship between the position of the dynamic response parameters of the vehicle body on the vehicle body and the installation position of the IMU; Based on the second correspondence and the installation position of the IMU, determine the dynamic response parameters of the vehicle body.

8. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the method for determining the dynamic response parameters of the vehicle body according to any one of claims 1 to 6.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the method for determining the dynamic response parameters of the vehicle body according to any one of claims 1 to 6.

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