A vehicle fusion positioning method, device and equipment

Abstract

The present application discloses a method, device and equipment for fusion positioning of a vehicle, wherein the method includes: obtaining the installation deviation angle between the IMU and the vehicle body, the vertical displacement of each tire of the vehicle relative to the vehicle body, the tire pressure of each tire, the dimensional parameters of each tire at the nominal tire pressure, the wheelbase, and the IMU attitude angle of the IMU relative to the navigation coordinate system when the vehicle body coordinate system and the vehicle speed coordinate system do not coincide; determining the pitch angle based on the tire pressure of each tire, the dimensional parameters at the nominal tire pressure, the vertical displacement relative to the vehicle body and the wheelbase of the vehicle; determining the wheel speed attitude angle based on the IMU attitude angle, the installation deviation angle and the pitch angle; and determining the fusion positioning information of the vehicle at the current moment based on the wheel speed, wheel speed attitude angle and the vehicle position information at the previous moment of the current moment when no GNSS signal of the global navigation satellite system is received. According to the embodiments of the present application, the accuracy of the fusion positioning result of the vehicle can be improved.

Description

Technical Field

[0001] The present application belongs to the field of autonomous driving technology, and in particular relates to a vehicle fusion positioning method, device and equipment. Background Art

[0002] In scenarios that rely heavily on high-precision positioning, such as map collection vehicles and autonomous vehicles, high-precision Global Navigation Satellite System (GNSS) or Inertial Measurement Unit (IMU) fusion positioning devices are usually used to obtain information such as their own position, posture, and velocity.

[0003] To ensure sufficiently accurate inertial dead reckoning positioning even when no GNSS signals are received, related technologies, such as known GNSS, IMU, or dead reckoning (DR) fusion positioning solutions, generally consider wheel speed as the speed of the vehicle along its longitudinal axis and use this to estimate the vehicle's positioning status.

[0004] However, due to uneven front and rear load distribution, or when the vehicle goes uphill or downhill, a pitch angle will be formed between the vehicle body and the road surface. Therefore, the actual wheel speed direction is the tangent direction of the tire-road contact surface, which is inconsistent with the vehicle body direction.

[0005] Related technologies use the wheel speed direction as the longitudinal axis direction of the vehicle for inertial calculation, which will introduce system errors and reduce the accuracy of the final fusion positioning. Summary of the Invention

[0006] The embodiments of the present application provide a vehicle fusion positioning method, device and equipment, which can improve the accuracy of the vehicle fusion positioning results.

[0007] On the one hand, an embodiment of the present application provides a vehicle fusion positioning method, characterized by including:

[0008] When the vehicle body coordinate system and the vehicle speed coordinate system do not coincide, obtain the installation deviation angle between the IMU and the vehicle body, the vertical displacement of each tire of the vehicle relative to the vehicle body, the tire pressure of each tire of the vehicle, the size parameters of each tire of the vehicle at the standard tire pressure, the wheelbase of the vehicle, and the IMU attitude angle of the IMU relative to the navigation coordinate system, and the origin of the vehicle speed coordinate system and the vehicle body coordinate system coincide.

[0009] Determine the pitch angle of the vehicle body relative to the road surface based on the tire pressure of each tire, the dimensional parameters of each tire at the nominal tire pressure, the vertical displacement of each tire relative to the vehicle body, and the wheelbase of the vehicle;

[0010] Determine the wheel speed attitude angle relative to the navigation coordinate system according to the IMU attitude angle, the installation deviation angle and the pitch angle,

[0011] In the absence of a GNSS signal, the fused positioning information of the vehicle at the current moment is determined based on the wheel speed of the vehicle at the current moment, the wheel speed attitude angle, and the vehicle position information at the moment before the current moment.

[0012] In a possible implementation, before obtaining the installation deviation angle between the IMU and the vehicle body, the method further includes:

[0013] When the longitudinal acceleration of the vehicle body is less than a preset longitudinal acceleration threshold and the displacement difference between the front and rear suspensions of the vehicle is less than a preset displacement difference, a state quantity affecting the fused positioning information is obtained;

[0014] According to the angular velocity, acceleration and wheel speed of the IMU at the current moment, the observation quantity is determined.

[0015] Kalman filtering is performed based on the state quantity and the observation quantity to obtain the installation deviation angle between the IMU and the vehicle body.

[0016] In one possible implementation, determining the observed quantity based on the angular velocity, acceleration, and wheel speed of the IMU at the current moment includes:

[0017] The dead reckoning is performed based on the vehicle position information at the previous moment and the angular velocity and acceleration of the IMU at the current moment to obtain the first vehicle position information at the current moment.

[0018] Performing dead reckoning based on the vehicle position information at the previous moment, the wheel speed, and the angular velocity to obtain the second vehicle position information at the current moment,

[0019] An observation value is obtained by calculating a difference between the first vehicle position information and the second vehicle position information.

[0020] In one possible implementation, determining the pitch angle of the vehicle body relative to the road surface based on the tire pressure of each tire, the dimensional parameters of each tire at the nominal tire pressure, the vertical displacement of each tire relative to the vehicle body, and the wheelbase of the vehicle includes:

[0021] Determine the height of the center of each tire from the road surface based on the tire pressure of each tire and the dimensional parameters of each tire at the nominal tire pressure.

[0022] The pitch angle of the vehicle body relative to the road surface is determined based on the vertical displacement of each tire relative to the vehicle body, the height of the center of each tire from the road surface, and the wheelbase of the vehicle.

[0023] In one possible implementation, determining the height of the center of each tire from the road surface based on the tire pressure of each tire and the dimensional parameters of each tire at the nominal tire pressure includes:

[0024] Calculate the height of each tire's center from the road surface using formulas (1) and (2):

[0025] Δρ=f(t n～n-x ) (1)

[0026] h=R(1-Δρ) (2)

[0027] Where h is the height of the tire center from the road surface, R is the size parameter of the tire at the nominal tire pressure state, and Δρ is the distance between the tire center and the road surface. n to t n-x The functional relationship between the tire deformation coefficient and tire pressure within x seconds.

[0028] In one possible implementation, determining the pitch angle of the vehicle body relative to the road surface based on the vertical displacement of each tire relative to the vehicle body, the height of the center of each tire from the road surface, and the wheelbase of the vehicle includes:

[0029] Calculate the pitch angle according to formula (3):

[0030]

[0031] Where, is the pitch angle, Δx lf , Δx rf , Δx lr , Δx rr are the vertical displacements of the left front tire, right front tire, left rear tire, and right rear tire relative to the vehicle body, respectively, h lf 、h rf 、h lr 、h rr are the heights of the center of the vehicle's left front tire, right front tire, left rear tire, and right rear tire from the road surface, L fr is the wheelbase of the vehicle.

[0032] In one possible implementation, determining the wheel speed attitude angle of the wheel speed relative to the navigation coordinate system based on the IMU attitude angle, the installation deviation angle, and the pitch angle includes:

[0033] The wheel speed attitude angle relative to the navigation coordinate system is calculated according to formula (4):

[0034]

[0035] Where n represents the navigation coordinate system, b represents the IMU coordinate system, v represents the vehicle coordinate system, and d represents the vehicle speed coordinate system. is the rotation matrix of the vehicle speed coordinate system relative to the navigation coordinate system, that is, the wheel speed attitude angle, is the rotation matrix of the IMU coordinate system relative to the navigation coordinate system, According to the IMU attitude angle, is the rotation matrix of the vehicle coordinate system relative to the IMU coordinate system, Calculated according to the installation deviation angle, is the rotation matrix of the vehicle speed coordinate system relative to the vehicle body coordinate system, It is calculated based on the pitch angle between the vehicle body and the road surface.

[0036] In a possible implementation, the method further includes:

[0037] Obtain the current vehicle's angular velocity, the previous vehicle's position information, the previous IMU's attitude angle, and the IMU's preset non-fixed axis rotation error compensation.

[0038] Determine the gravitational acceleration based on the vehicle position information at the previous moment,

[0039] The IMU attitude angle at the current moment is obtained according to the angular velocity, the IMU attitude angle at the previous moment and the preset non-fixed axis rotation error compensation,

[0040] Correct the IMU attitude angle at the current moment according to the gravity acceleration, or,

[0041] When a global navigation satellite system GNSS signal is received, the IMU attitude angle at the current moment is corrected using the GNSS signal.

[0042] On the other hand, an embodiment of the present application provides a fusion positioning device for a vehicle, the device comprising:

[0043] An acquisition module is used to acquire, when the vehicle body coordinate system and the vehicle speed coordinate system do not coincide with each other, an installation deviation angle between the IMU and the vehicle body, a vertical displacement of each tire of the vehicle relative to the vehicle body, a tire pressure of each tire of the vehicle, a dimensional parameter of each tire of the vehicle at a standard tire pressure, a wheelbase of the vehicle, and an IMU attitude angle of the IMU relative to the navigation coordinate system, wherein the origins of the vehicle speed coordinate system and the vehicle body coordinate system coincide with each other.

[0044] a first determining module configured to determine a pitch angle of the vehicle body relative to the road surface based on the tire pressure of each tire, the dimensional parameters of each tire at the nominal tire pressure, the vertical displacement of each tire relative to the vehicle body, and the wheelbase of the vehicle;

[0045] The second determining module is configured to determine the wheel speed attitude angle relative to the navigation coordinate system based on the IMU attitude angle, the installation deviation angle and the pitch angle.

[0046] The fusion positioning module is used to determine the fusion positioning information of the vehicle at the current moment based on the wheel speed of the vehicle at the current moment, the wheel speed attitude angle and the vehicle position information at the previous moment when no global navigation satellite system GNSS signal is received.

[0047] In another aspect, an embodiment of the present application provides a vehicle fusion positioning device, the device comprising: a processor and a memory storing computer program instructions,

[0048] When the processor executes the computer program instructions, the vehicle fusion positioning method as described in any one of the above items is implemented.

[0049] On the other hand, an embodiment of the present application provides a computer-readable storage medium, on which computer program instructions are stored. When the computer program instructions are executed by a processor, the vehicle fusion positioning method as described in any one of the above is implemented.

[0050] On the other hand, an embodiment of the present application provides a computer program product. When the instructions in the computer program product are executed by a processor of an electronic device, the electronic device executes the vehicle fusion positioning method as described in any one of the above.

[0051] The vehicle fusion positioning method, device and equipment of the embodiments of the present application determine the pitch angle of the vehicle body relative to the road surface based on the tire pressure of each tire, the dimensional parameters of each tire at the nominal tire pressure, the vertical displacement of each tire relative to the vehicle body and the wheelbase of the vehicle when the vehicle body coordinate system and the vehicle speed coordinate system do not overlap. The actual direction of the wheel speed that is different from the vehicle body direction when the vehicle body is not parallel to the road surface, that is, the wheel speed attitude angle, is determined based on the IMU attitude angle, the installation deviation angle and the pitch angle. In the absence of a global navigation satellite system GNSS signal, the wheel speed vector of the vehicle that is consistent with the vehicle body direction is determined based on the current vehicle wheel speed collected in real time by the speedometer and the wheel speed attitude angle that represents the actual direction of the wheel speed. The vehicle positioning is then calculated based on the wheel speed vector of the vehicle that is consistent with the vehicle body direction and the vehicle position information at the previous moment to determine the fusion positioning information of the vehicle at the current moment, thereby improving the accuracy of the vehicle's fusion positioning. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0053] Figure 1 is a schematic diagram of the coordinate system provided in the embodiment of the present application,

[0054] Figure 2 This is a flow chart of a vehicle fusion positioning method provided in an embodiment of the present application.

[0055] Figure 3 is a schematic diagram of a process for determining a pitch angle provided in an embodiment of the present application.

[0056] Figure 4 : is an application diagram of the vehicle fusion positioning method provided in an embodiment of the present application,

[0057] Figure 5 is a structural diagram of a vehicle fusion positioning device provided in an embodiment of the present application,

[0058] Figure 6 It is a structural diagram of the vehicle fusion positioning device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0059] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is merely to provide a better understanding of the present application by illustrating the examples of the present application.

[0060] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, the elements defined by the phrase "comprising..." do not exclude the presence of other identical elements in the process, method, article, or device comprising the elements.

[0061] When the front and rear loads of a vehicle are unevenly distributed, a pitch angle will be formed between the vehicle body and the road surface. At this time, the actual wheel speed direction is inconsistent with the vehicle body direction. The relevant technology still performs inertial estimation of vehicle positioning based on the vehicle's driving direction and wheel speed, and the estimated vehicle positioning results have errors.

[0062] Based on this, the inventors determined the actual direction of the wheel speed when the vehicle body is not parallel to the road surface based on the IMU attitude angle, the installation deviation angle between the IMU and the vehicle body, and the pitch angle between the vehicle body and the road surface. In the case of uneven front and rear load distribution of the vehicle, this method can be used to determine the actual direction of the wheel speed when the vehicle body is not parallel to the road surface. In this way, inertial calculation of vehicle positioning can be performed based on the vehicle's wheel speed and the actual direction of the wheel speed when no GNSS signal is received, reducing the error in inertial calculation and improving the accuracy of the vehicle's fused positioning information at the current moment.

[0063] In order to solve the problems of the prior art, the embodiments of the present application provide a vehicle fusion positioning method, device and apparatus. The vehicle fusion positioning method provided by the embodiments of the present application is first introduced below.

[0064] To facilitate understanding of this application, first Figure 1 Explain the three coordinate systems mentioned in this application: IMU coordinate system, vehicle body coordinate system and vehicle speed coordinate system. Figure 1 It is a schematic diagram of the coordinate system provided in the embodiment of the present application.

[0065] IMU coordinate system OX m Y m Z m The origin O is the geometric center of the IMU, and the coordinate axis OX m Pointing to the right side of the IMU, coordinate axis OY m Pointing to the front side of the IMU, coordinate axis OZ m Point upwards towards the IMU.

[0066] Vehicle coordinate system OX v Y v Z v The origin O is the midpoint of the projection line of the vehicle's rear axle on the ground, and the coordinate axis OX v Pointing to the right side of the vehicle, coordinate axis OY v Pointing to the center axis of the vehicle, coordinate axis OZ v Perpendicular to OX v Y v The plane points upwards towards the vehicle.

[0067] When a vehicle is driving on the road, the tire speed is constrained by the ground. For common working conditions, the tire speed direction is considered to be the tangent direction of the intersection of the wheel plane and the ground at the contact point between the wheel and the ground. Therefore, the vehicle speed coordinate system OXd Y d Z d The origin O is the midpoint of the projection line of the vehicle's rear axle on the ground, and the coordinate axis OY d The tangent line of the intersection of the vehicle's symmetry plane and the ground at point O points to the front of the vehicle, the coordinate axis OZ d is the normal of the ground at point O, pointing to the sky, coordinate axis OX d Perpendicular to OY d Z d The flat surface points toward the right side of the vehicle.

[0068] Based on the above coordinate system, the specific implementation of the fusion positioning method provided by this application is introduced below. Figure 2 This is a flow chart of the vehicle fusion positioning method provided by the embodiment of the present application, such as Figure 2 As shown, the vehicle fusion positioning method provided in the embodiment of the present application includes the following steps: S201 to S204.

[0069] S201, when the vehicle body coordinate system and the vehicle speed coordinate system do not coincide, obtain the installation deviation angle between the IMU and the vehicle body, the vertical displacement of each tire of the vehicle relative to the vehicle body, the tire pressure of each tire of the vehicle, the dimensional parameters of each tire of the vehicle at the standard tire pressure, the wheelbase of the vehicle, and the IMU attitude angle of the IMU relative to the navigation coordinate system.

[0070] As an implementation of S201, the vertical displacement of each tire relative to the vehicle body, the tire pressure of each tire, the dimensional parameters of each tire at standard tire pressure, the vehicle wheelbase, and the IMU attitude angle relative to the navigation coordinate system are obtained via a vehicle control bus or wireless local area network of the vehicle. The installation deviation angle between the IMU and the vehicle body is obtained from the computing unit.

[0071] In another implementation of S201, the dimensional parameters of each tire at standard tire pressure and the vehicle's wheelbase are pre-stored in a storage module of the vehicle. The vertical displacement of each tire relative to the vehicle body is obtained from a displacement sensor mounted on the vehicle's suspension. The tire pressure of each tire is obtained from a tire pressure gauge mounted in each tire of the vehicle.

[0072] In one embodiment, the origins of the vehicle speed coordinate system and the vehicle body coordinate system coincide with each other.

[0073] In one embodiment, situations where the vehicle body coordinate system and the vehicle speed coordinate system do not coincide include: the vehicle rapidly decelerating, a serious imbalance in the front and rear loads of the vehicle, or the vehicle traveling on a steep slope.

[0074] S202: Determine the pitch angle of the vehicle body relative to the road surface based on the tire pressure of each tire, the dimensional parameters of each tire at the nominal tire pressure, the vertical displacement of each tire relative to the vehicle body, and the wheelbase of the vehicle.

[0075] As an implementation method of S202, the height of the center of each tire from the road surface is determined based on the tire pressure of each tire and the dimensional parameters of each tire at the nominal tire pressure, and the pitch angle of the vehicle body relative to the road surface is determined based on the vertical displacement of each tire relative to the vehicle body, the height of the center of each tire from the road surface and the wheelbase of the vehicle.

[0076] When measuring the vertical displacement of the tire relative to the vehicle body, considering that the tire will deform as the load and tire pressure change, resulting in an angle between the vehicle body and the road surface, it is also necessary to measure the height of the tire center from the ground. Tire pressure gauges can be installed in the four tires to measure the real-time tire pressure, establish a functional relationship between the tire deformation coefficient and tire pressure, and determine the height of the center of each tire from the road surface through the functional relationship between the tire deformation coefficient and tire pressure.

[0077] In one embodiment, to accurately determine the pitch angle between the vehicle body and the road surface, the height of the center of each tire from the road surface is determined based on the tire pressure of each tire and the dimensional parameters of each tire at the nominal tire pressure, including:

[0078] Calculate the height of each tire's center from the road surface using formulas (1) and (2):

[0079] Δρ=f(t n～n-x ) (1)

[0080] h=R(1-Δρ) (2)

[0081] Where h is the height of the tire center from the road surface, R is the size parameter of the tire at the nominal tire pressure state, and Δρ is the distance between the tire center and the road surface. n to t n-x The functional relationship between the tire deformation coefficient and tire pressure within x seconds.

[0082] Therefore, based on the relationship between the tire deformation coefficient and tire pressure, the height of the center of each tire from the road surface is determined, which facilitates the subsequent accurate determination of the pitch angle between the vehicle body and the road surface.

[0083] In one embodiment, the vertical displacement of the tire relative to the vehicle body can be obtained by installing displacement sensors on the four suspensions of the vehicle.

[0084] In another embodiment, since the tire pressure at a single moment cannot be used to describe the deformation state of the tire, a function of the tire deformation coefficient is established by establishing tire pressure data within the range of 40 seconds before and at the moment n.

[0085] In another embodiment, a camera is used to capture tire images, and the tire area and contact patch area are extracted to calculate tire deformation.

[0086] In another embodiment, a magnetic field is applied to the steel cords inside the tire belt layer so that the belt layer forms a resonant circuit, and the tire deformation is determined by measuring the resonant frequency.

[0087] In one embodiment, determining the pitch angle of the vehicle body relative to the road surface based on the vertical displacement of each tire relative to the vehicle body, the height of the center of each tire from the road surface, and the wheelbase of the vehicle includes:

[0088] Calculate the pitch angle according to formula (3):

[0089]

[0090] Where, is the pitch angle, Δx lf , Δx rf , Δx lr , Δx rr are the vertical displacements of the left front tire, right front tire, left rear tire, and right rear tire relative to the vehicle body, respectively, h lf 、h rf 、h lr 、h rr are the heights of the center of the vehicle's left front tire, right front tire, left rear tire, and right rear tire from the road surface, L fr is the wheelbase of the vehicle.

[0091] Thus, the pitch angle of the vehicle body relative to the road surface is determined based on the vertical displacement of each tire relative to the vehicle body, the height of the center of each tire from the road surface, and the wheelbase of the vehicle.

[0092] The following is a combination Figure 3 As described in the above formula (3), the calculation of the pitch angle between the vehicle body and the road surface includes variables: S301-S304. Figure 3 This is a schematic diagram of the process of determining the pitch angle provided in an embodiment of the present application.

[0093] S301, vertical displacement of each tire of the vehicle relative to the vehicle body,

[0094] S302, the height of each tire's center from the road surface,

[0095] S303, vehicle wheelbase,

[0096] S304, the pitch angle between the vehicle body and the road surface.

[0097] S203: Determine the wheel speed attitude angle relative to the navigation coordinate system based on the IMU attitude angle, installation deviation angle, and pitch angle.

[0098] As an implementation of S203, the wheel speed attitude angle of the vehicle speed relative to the navigation coordinate system can be calculated according to formula (4):

[0099]

[0100] Where n represents the navigation coordinate system, b represents the IMU coordinate system, v represents the vehicle coordinate system, and d represents the vehicle speed coordinate system. is the rotation matrix of the vehicle speed coordinate system relative to the navigation coordinate system, that is, the wheel speed attitude angle, is the rotation matrix of the IMU coordinate system relative to the navigation coordinate system, According to the IMU attitude angle, is the rotation matrix of the vehicle coordinate system relative to the IMU coordinate system, Calculated according to the installation deviation angle, is the rotation matrix of the vehicle speed coordinate system relative to the vehicle body coordinate system, Calculated based on the pitch angle between the vehicle body and the road surface.

[0101] Therefore, the wheel speed attitude angle of the vehicle relative to the navigation coordinate system is determined by combining the IMU attitude angle, installation deviation angle and pitch angle, that is, the actual direction of the wheel speed is determined.

[0102] S204 , when no GNSS signal is received, determining the fused positioning information of the vehicle at the current moment according to the wheel speed, wheel speed attitude angle of the vehicle at the current moment and the vehicle position information at the moment before the current moment.

[0103] As an implementation method of S204, the wheel speed vector of the vehicle consistent with the direction of the vehicle body is determined based on the wheel speed of the vehicle at the current moment collected in real time by the speedometer and the wheel speed attitude angle representing the actual direction of the wheel speed. Then, based on the wheel speed vector of the vehicle consistent with the direction of the vehicle body and the vehicle position information at the moment before the current moment, the vehicle positioning is calculated to determine the fused positioning information of the vehicle at the current moment.

[0104] The vehicle fusion positioning method of the embodiment of the present application determines the pitch angle of the vehicle body relative to the road surface based on the tire pressure of each tire, the dimensional parameters of each tire at the nominal tire pressure, the vertical displacement of each tire relative to the vehicle body, and the wheelbase of the vehicle when the vehicle body coordinate system and the vehicle speed coordinate system do not coincide. The actual direction of the wheel speed that is different from the vehicle body direction when the vehicle body is not parallel to the road surface, that is, the wheel speed attitude angle, is determined based on the IMU attitude angle, the installation deviation angle, and the pitch angle. In the absence of a global navigation satellite system GNSS signal, the wheel speed vector of the vehicle that is consistent with the vehicle body direction is determined based on the current vehicle speed collected in real time by the speedometer and the wheel speed attitude angle that represents the actual direction of the wheel speed. The vehicle positioning is then estimated based on the wheel speed vector of the vehicle that is consistent with the vehicle body direction and the vehicle position information at the previous moment before the current moment, and the fusion positioning information of the vehicle at the current moment is determined, thereby improving the accuracy of the vehicle's fusion positioning.

[0105] In one possible implementation, in order to improve the fusion positioning accuracy of the vehicle, before S201, the installation deviation angle of the IMU relative to the navigation coordinate system can be determined:

[0106] Due to factors such as processing and installation, it is difficult to ensure that the IMU coordinate system and the vehicle coordinate system remain parallel, and it is also difficult to measure the installation deviation angle between the IMU and the vehicle body.

[0107] In one embodiment, the installation deviation angle is obtained by precise measurement.

[0108] In another embodiment, the installation deviation angle is obtained by system-level calibration. The following example illustrates a method for calculating the installation deviation angle between the IMU and the vehicle body through system calibration.

[0109] In one embodiment, when the longitudinal acceleration of the vehicle body is less than a preset longitudinal acceleration threshold and the displacement difference between the front and rear suspensions of the vehicle is less than a preset displacement difference, the vehicle body can be regarded as parallel to the ground, and the state quantity affecting the fusion positioning information is obtained.

[0110] In one embodiment, based on the deviation of attitude angle, speed, position, constant zero bias of each axis of IMU, IMU non-orthogonality error, pitch and yaw angle installed between IMU and vehicle body, and wheel speed scale coefficient error, a state quantity that can represent the vehicle estimation error is determined, so as to facilitate the subsequent estimation of the installation deviation angle between IMU and vehicle body based on the observed quantity.

[0111] The observed value is determined based on the angular velocity, acceleration and wheel speed of the IMU at the current moment.

[0112] In one possible implementation, to improve the vehicle's fusion positioning accuracy, dead reckoning can be performed based on the vehicle's position information at the previous moment and the angular velocity and acceleration of the IMU at the current moment to obtain the first vehicle position information at the current moment. Dead reckoning can be performed based on the vehicle's position information at the previous moment, the wheel speed, and angular velocity to obtain the second vehicle position information at the current moment. The difference between the first and second vehicle position information can be calculated to obtain an observation value.

[0113] Therefore, the vehicle position calculated by the angular velocity and acceleration of the IMU and the vehicle position calculated based on the wheel speed and angular velocity are used to determine the observation quantity that can represent the vehicle position estimation error, so as to improve the fusion positioning accuracy of the vehicle calculated based on the observation quantity.

[0114] Kalman filtering is performed based on the state quantity and observation quantity to obtain the installation deviation angle between the IMU and the vehicle body.

[0115] In one embodiment, the attitude angle between the IMU coordinate system and the vehicle body coordinate system is set to [η x η y η z ], through theoretical derivation, it can be found that η in the installation error angle y It will not affect the projection of the wheel speed meter's speed under the navigation coordinates, nor will it affect its position estimation. As an error source term considering the difference in inertial estimation between the odometer and IMU, the installation deviation angle η between the IMU and the vehicle body can be estimated by performing Kalman filtering based on the state quantity X and the observation quantity Z. x and η z , that is, the installation deviation angle between the IMU and the vehicle body is obtained.

[0116] Therefore, when the origins of the IMU coordinate system and the vehicle coordinate system coincide, the installation deviation angle between the IMU and the vehicle body is determined, which facilitates the subsequent determination of the wheel speed rotation matrix relative to the navigation coordinate system based on the installation deviation angle, thereby improving the vehicle's fusion positioning accuracy.

[0117] The above S201-S204 are how to determine the fused positioning information of the vehicle when no GNSS signal is received.

[0118] In one possible implementation, after the vehicle starts moving, the spatial attitude angle recursive formula can be used to perform integration operations to obtain the IMU attitude angle at each moment. When a GNSS signal is received, the IMU attitude angle is integrated with the GNSS to ensure that the final output IMU attitude angle is very reliable.

[0119] In one possible implementation, the angular velocity of the vehicle at the current moment, the vehicle position information at the previous moment, the IMU attitude angle at the previous moment, and the preset non-fixed axis rotation error compensation of the IMU are obtained.

[0120] Determine the acceleration of gravity based on the vehicle position information at the previous moment,

[0121] According to the angular velocity, the IMU attitude angle of the previous moment and the preset non-fixed axis rotation error compensation, the IMU attitude angle of the current moment is obtained.

[0122] Correct the current IMU attitude angle according to the gravity acceleration, or,

[0123] When the GNSS signal is received, the IMU attitude angle at the current moment is corrected using the GNSS signal.

[0124] Therefore, the gravity acceleration is taken into account when updating the IMU attitude angle, thereby improving the accuracy of the IMU attitude angle. Alternatively, when receiving the Global Navigation Satellite System GNSS signal, the IMU attitude angle is updated in combination with the GNS signal, thereby further improving the accuracy of the IMU attitude angle.

[0125] Figure 4 This is a schematic diagram of the application of the vehicle fusion positioning method provided in the embodiment of the present application, combined with Figure 4 As described above, vehicle fusion positioning includes steps S401-S406.

[0126] S401, real-time acquisition of the angular velocity of each direction of the IMU,

[0127] S402, obtaining a preset non-fixed axis error compensation,

[0128] S403: Determine the rotation matrix of the IMU relative to the inertial coordinate system based on the angular velocities in each direction and the preset non-fixed axis error compensation of the IMU. The inertial coordinate system refers to a coordinate system that conforms to Newton's laws of motion.

[0129] Thus, S401-S403 realizes real-time determination of the rotation matrix of the IMU relative to the inertial coordinate system according to the changes of the IMU.

[0130] S404: Determine a rotation matrix of the navigation coordinate system relative to the inertial coordinate system based on the vehicle position information at the previous moment.

[0131] S405: Obtain the IMU attitude angle of the current moment relative to the navigation coordinate system based on the rotation matrix of the navigation coordinate system relative to the inertial coordinate system and the rotation matrix of the IMU relative to the inertial coordinate system.

[0132] Therefore, S404-S405 realizes updating the IMU attitude angle according to the vehicle position information.

[0133] S406, when receiving the global navigation satellite system GNSS signal, determine the fused positioning information of the vehicle at the current moment based on the vehicle's angular velocity at the current moment, the vehicle's position information at the previous moment, the IMU attitude angle at the previous moment, and the satellite positioning data measured by GNSS. The vehicle's fused positioning information includes: vehicle position information, IMU attitude angle and state quantity.

[0134] Thus, S406 is implemented to determine the fused positioning information of the vehicle at the current moment when the global navigation satellite system GNSS signal is received.

[0135] Based on the vehicle fusion positioning method provided in the embodiment of the present application, accordingly, the embodiment of the present application also provides a vehicle fusion positioning device. Figure 5 This is a schematic diagram of the structure of the vehicle fusion positioning device provided in the embodiment of the present application. Figure 5 As shown, the vehicle fusion positioning device 500 provided in the embodiment of the present application includes:

[0136] The acquisition module 501 is used to obtain the installation deviation angle between the IMU and the vehicle body, the vertical displacement of each tire of the vehicle relative to the vehicle body, the tire pressure of each tire of the vehicle, the dimensional parameters of each tire of the vehicle at the standard tire pressure, the wheelbase of the vehicle, and the IMU attitude angle of the IMU relative to the navigation coordinate system when the vehicle body coordinate system and the vehicle speed coordinate system do not coincide with each other, and the origin of the vehicle speed coordinate system and the vehicle body coordinate system coincide with each other.

[0137] The first determining module 502 is configured to determine the pitch angle of the vehicle body relative to the road surface based on the tire pressure of each tire, the dimensional parameters of each tire at the nominal tire pressure, the vertical displacement of each tire relative to the vehicle body, and the wheelbase of the vehicle.

[0138] The second determining module 503 is used to determine the wheel speed attitude angle relative to the navigation coordinate system based on the IMU attitude angle, installation deviation angle and pitch angle,

[0139] The fusion positioning module 504 is used to determine the fusion positioning information of the vehicle at the current moment based on the wheel speed, wheel speed attitude angle and vehicle position information at the previous moment of the current moment when no global navigation satellite system GNSS signal is received.

[0140] The fusion positioning device for a vehicle in an embodiment of the present application determines, when the vehicle coordinate system and the vehicle speed coordinate system do not coincide, the pitch angle of the vehicle body relative to the road surface based on the tire pressure of each tire, the dimensional parameters of each tire at the nominal tire pressure, the vertical displacement of each tire relative to the vehicle body, and the wheelbase of the vehicle. The actual direction of the wheel speed that is different from the vehicle body direction when the vehicle body is not parallel to the road surface, i.e., the wheel speed attitude angle, is determined based on the IMU attitude angle, the installation deviation angle, and the pitch angle. In the absence of a global navigation satellite system GNSS signal, the wheel speed vector of the vehicle that is consistent with the vehicle body direction is determined based on the current vehicle speed collected in real time by the speedometer and the wheel speed attitude angle that represents the actual direction of the wheel speed. The vehicle positioning is then estimated based on the wheel speed vector of the vehicle that is consistent with the vehicle body direction and the vehicle position information at the previous moment before the current moment, and the fusion positioning information of the vehicle at the current moment is determined, thereby improving the accuracy of the vehicle's fusion positioning.

[0141] In one possible implementation, to improve the fusion positioning accuracy of the vehicle, before obtaining the installation deviation angle between the IMU and the vehicle body, the fusion positioning device 500 for the vehicle provided in the embodiment of the present application may further include:

[0142] The state quantity acquisition module is used to obtain the state quantity that affects the fusion positioning information when the longitudinal acceleration of the vehicle body is less than the preset longitudinal acceleration threshold and the displacement difference between the front and rear suspensions of the vehicle is less than the preset displacement difference.

[0143] The observation determination module is used to determine the observation quantity based on the angular velocity, acceleration and wheel speed of the IMU at the current moment.

[0144] The filtering module is used to perform Kalman filtering based on the state quantity and observation quantity to obtain the installation deviation angle between the IMU and the vehicle body.

[0145] Therefore, when the origins of the IMU coordinate system and the vehicle coordinate system coincide, the installation deviation angle between the IMU and the vehicle body is determined, which facilitates the subsequent determination of the wheel speed attitude angle based on the installation deviation angle, thereby improving the vehicle's fusion positioning accuracy.

[0146] In one possible implementation, in order to improve the fusion positioning accuracy of the vehicle, the observation determination module may also be used to:

[0147] The first vehicle position information at the current moment is obtained by performing dead reckoning based on the vehicle position information at the previous moment and the angular velocity and acceleration of the IMU at the current moment.

[0148] The dead reckoning is performed based on the vehicle position information, wheel speed and angular velocity at the previous moment to obtain the second vehicle position information at the current moment.

[0149] An observation value is obtained by calculating the difference between the first vehicle position information and the second vehicle position information.

[0150] Therefore, the vehicle position obtained by dead reckoning based on the angular velocity and acceleration of the IMU and the vehicle position obtained by dead reckoning based on the wheel speed and angular velocity are used to determine the observation value that can represent the vehicle position estimation error, so as to facilitate improving the fusion positioning accuracy of the vehicle calculated based on the observation value.

[0151] In a possible implementation, in order to accurately determine the pitch angle between the vehicle body and the road surface, the first determining module 502 may also be configured to:

[0152] According to the tire pressure of each tire and the size parameters of each tire at the nominal tire pressure, determine the height of the center of each tire from the road surface.

[0153] The pitch angle of the vehicle body relative to the road surface is determined based on the vertical displacement of each tire relative to the vehicle body, the height of the center of each tire from the road surface, and the wheelbase of the vehicle.

[0154] In a possible implementation, the first determining module 502 may also be configured to calculate the height of the center of each tire from the road surface according to formulas (1) and (2).

[0155] In a possible implementation, the first determining module 502 may also be configured to calculate the pitch angle according to formula (3).

[0156] In a possible implementation, the second determining module 503 may also be configured to calculate the wheel speed attitude angle relative to the navigation coordinate system according to formula (4).

[0157] In one possible implementation, in order to improve the accuracy of the fusion positioning result, the vehicle fusion positioning device 500 provided in the embodiment of the present application may further include:

[0158] The information acquisition module is used to obtain the current vehicle's angular velocity, the vehicle's position information at the previous moment, the IMU attitude angle at the previous moment, and the IMU's preset non-fixed axis rotation error compensation.

[0159] The gravity acceleration determination module determines the gravity acceleration based on the vehicle position information at the previous moment.

[0160] The IMU attitude angle determination module is used to obtain the current IMU attitude angle based on the angular velocity, the previous IMU attitude angle and the preset non-fixed axis rotation error compensation.

[0161] The first correction module is used to correct the IMU attitude angle at the current moment according to the gravity acceleration, or,

[0162] The second correction module is used to correct the IMU attitude angle at the current moment through the GNSS signal when a global navigation satellite system GNSS signal is received.

[0163] Therefore, the gravity acceleration is taken into account when the IMU attitude angle is updated, thereby improving the accuracy of the IMU attitude angle. Alternatively, when a global navigation satellite system GNSS signal is received, the GNSS signal is taken into account when the IMU attitude angle is updated, thereby improving the accuracy of the IMU attitude angle.

[0164] Figure 6 This is a schematic diagram of the structure of the vehicle fusion positioning device provided in the embodiment of the present application. Figure 6 As shown, the fusion positioning device in the vehicle may include a processor 601 and a memory 602 storing computer program instructions.

[0165] Specifically, the processor 601 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0166] The memory 602 may include a large capacity memory for data or instructions. By way of example and not limitation, the memory 602 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive, or a combination of two or more of these. Where appropriate, the memory 602 may include removable or non-removable (or fixed) media. Where appropriate, the memory 602 may be inside or outside the integrated gateway disaster recovery device. In a specific embodiment, the memory 602 is a non-volatile solid-state memory.

[0167] The memory 602 may include read-only memory (ROM), random access memory (RAM), magnetic disk storage media devices, optical storage media devices, flash memory devices, electrical, optical or other physical / tangible memory storage devices. Thus, generally, the memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., memory devices) encoded with software including computer-executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the method according to an aspect of the present application.

[0168] The processor 601 reads and executes computer program instructions stored in the memory 602 to implement any one of the vehicle fusion positioning methods in the above embodiments.

[0169] In one example, the fusion positioning device of the vehicle may further include a communication interface 603 and a bus 610. Figure 6 As shown, the processor 601, the memory 602, and the communication interface 603 are connected via a bus 610 and communicate with each other.

[0170] The communication interface 603 is mainly used to implement communication between various modules, devices, units and / or equipment in the embodiments of the present application.

[0171] Bus 610 includes hardware, software or both, and couples the components of the fusion positioning device of the vehicle to each other. For example, and not limitation, bus may include accelerated graphics port (AGP) or other graphics bus, enhanced industry standard architecture (EISA) bus, front side bus (FSB), hypertransport (HT) interconnection, industry standard architecture (ISA) bus, infinite bandwidth interconnection, low pin count (LPC) bus, memory bus, micro channel architecture (MCA) bus, peripheral component interconnect (PCI) bus, PCI-Express (PCI-X) bus, serial advanced technology attachment (SATA) bus, video electronics standard association local (VLB) bus or other suitable bus or two or more of these combinations. Where appropriate, bus 610 may include one or more buses. Although the present application embodiment describes and shows a specific bus, the application considers any suitable bus or interconnection.

[0172] The vehicle fusion positioning device can execute the vehicle fusion positioning method in the embodiment of the present application, thereby realizing the combination of Figure 2 and Figure 5 A vehicle fusion positioning method and device are described.

[0173] In combination with the vehicle fusion positioning method in the above embodiments, an embodiment of the present application also provides a computer-readable storage medium, on which computer program instructions are stored. When the computer program instructions are executed by a processor, a vehicle fusion positioning method such as any one of the above is implemented.

[0174] In combination with the vehicle fusion positioning method in the above embodiments, an embodiment of the present application also provides a computer program product. When the instructions in the computer program product are executed by the processor of an electronic device, the electronic device executes the vehicle fusion positioning method such as any one of the above.

[0175] It should be understood that the present application is not limited to the specific configurations and processes described above and illustrated in the figures. For the sake of brevity, a detailed description of known methods is omitted here. In the above embodiments, several specific steps are described and illustrated as examples. However, the method process of the present application is not limited to the specific steps described and illustrated. Those skilled in the art can make various changes, modifications, and additions, or change the order of the steps after understanding the spirit of the present application.

[0176] The functional blocks shown in the above-described block diagram can be implemented as hardware, software, firmware or a combination thereof. When implemented in hardware, they can be, for example, electronic circuits, application specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of the present application are programs or code segments that are used to perform the required tasks. The program or code segment can be stored in a machine-readable medium, or transmitted on a transmission medium or a communication link by a data signal carried in a carrier wave. "Machine-readable medium" can include any medium that can store or transmit information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROMs, flash memories, erasable ROMs (EROMs), floppy disks, CD-ROMs, optical disks, hard disks, optical fiber media, radio frequency (RF) links, etc. The code segment can be downloaded via a computer network such as the Internet, an intranet, etc.

[0177] It should also be noted that the exemplary embodiments mentioned in this application describe some methods or systems based on a series of steps or devices. However, this application is not limited to the order of the above steps. In other words, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.

[0178] The above reference is according to the flowchart and / or block diagram of the method, device and computer program product of the embodiment of the application, describes various aspects of the application.It should be understood that each box in the flowchart and / or block diagram and the combination of each box in the flowchart and / or block diagram can be realized by computer program instructions.These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer or other programmable data processing device to produce a kind of machine, so that these instructions executed by the processor of the computer or other programmable data processing device enable the realization of the function / action specified in one or more boxes of the flowchart and / or block diagram.Such a processor can be but is not limited to a general-purpose processor, a special-purpose processor, a special application processor or a field programmable logic circuit.It is also understood that each box in the block diagram and / or flowchart and the combination of the boxes in the block diagram and / or flowchart can also be realized by the dedicated hardware that performs the specified function or action, or can be realized by the combination of dedicated hardware and computer instructions.

[0179] The above description is only a specific embodiment of the present application. Those skilled in the art will clearly understand that for the convenience and brevity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the scope of protection of the present application is not limited thereto. Any person skilled in the art can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be included in the scope of protection of the present application.

Claims

1. A vehicle fusion positioning method, characterized in that: include: In the case where the vehicle body coordinate system and the vehicle speed coordinate system do not coincide, the installation deviation angle between the IMU and the vehicle body, the vertical displacement of each tire of the vehicle relative to the vehicle body, the tire pressure of each tire of the vehicle, the size parameters of each tire of the vehicle at the nominal tire pressure, the wheelbase of the vehicle, and the IMU attitude angle of the IMU relative to the navigation coordinate system are obtained. The origin of the vehicle speed coordinate system and the vehicle body coordinate system coincides, and the vehicle speed coordinate system OX d Y d Z d The midpoint of the projection line of the rear axle of the vehicle on the ground is taken as the origin O, and the tangent line of the intersection line of the vehicle symmetry plane and the ground pointing to the axle direction at the origin is taken as the coordinate axis OX d , with the normal line from the ground at the origin pointing to the sky as the coordinate axis OZ d , perpendicular to OY d Z d The straight line pointing to the right side of the vehicle is the coordinate axis OX d ; Determine the pitch angle of the vehicle body relative to the road surface based on the tire pressure of each tire, the dimensional parameters of each tire at the nominal tire pressure, the vertical displacement of each tire relative to the vehicle body, and the wheelbase of the vehicle; Determine the wheel speed attitude angle relative to the navigation coordinate system according to the IMU attitude angle, the installation deviation angle and the pitch angle, In the absence of a GNSS signal, the fused positioning information of the vehicle at the current moment is determined based on the wheel speed of the vehicle at the current moment, the wheel speed attitude angle, and the vehicle position information at the moment before the current moment.

2. The vehicle fusion positioning method according to claim 1, characterized in that: Before obtaining the installation deviation angle between the IMU and the vehicle body, the method further includes: When the longitudinal acceleration of the vehicle body is less than a preset longitudinal acceleration threshold and the displacement difference between the front and rear suspensions of the vehicle is less than a preset displacement difference, a state quantity affecting the fused positioning information is obtained; According to the angular velocity, acceleration and wheel speed of the IMU at the current moment, the observation quantity is determined. Kalman filtering is performed based on the state quantity and the observation quantity to obtain the installation deviation angle between the IMU and the vehicle body.

3. The vehicle fusion positioning method according to claim 2, characterized in that: Determining the observed quantity based on the angular velocity, acceleration, and wheel speed of the IMU at the current moment includes: The dead reckoning is performed based on the vehicle position information at the previous moment and the angular velocity and acceleration of the IMU at the current moment to obtain the first vehicle position information at the current moment. Performing dead reckoning based on the vehicle position information at the previous moment, the wheel speed, and the angular velocity to obtain the second vehicle position information at the current moment, An observation value is obtained by calculating a difference between the first vehicle position information and the second vehicle position information.

4. The vehicle fusion positioning method according to claim 1, characterized in that: Determining the pitch angle of the vehicle body relative to the road surface based on the tire pressure of each tire, the dimensional parameters of each tire at the nominal tire pressure, the vertical displacement of each tire relative to the vehicle body, and the wheelbase of the vehicle includes: Determine the height of the center of each tire from the road surface based on the tire pressure of each tire and the dimensional parameters of each tire at the nominal tire pressure. The pitch angle of the vehicle body relative to the road surface is determined based on the vertical displacement of each tire relative to the vehicle body, the height of the center of each tire from the road surface, and the wheelbase of the vehicle.

5. The vehicle fusion positioning method according to claim 4, characterized in that: Determining the height of the center of each tire from the road surface based on the tire pressure of each tire and the dimensional parameters of each tire at the nominal tire pressure includes: Calculate the height of each tire's center from the road surface using formulas (1) and (2): Δρ=f(t n～n-x ) (1) h=R(1-Δρ) (2) Where h is the height of the tire center from the road surface, R is the size parameter of the tire at the nominal tire pressure state, and Δρ is the distance between the tire center and the road surface. n to t n-x The functional relationship between the tire deformation coefficient and tire pressure within x seconds.

6. The vehicle fusion positioning method according to claim 4, characterized in that: Determining the pitch angle of the vehicle body relative to the road surface based on the vertical displacement of each tire relative to the vehicle body, the height of the center of each tire from the road surface, and the wheelbase of the vehicle includes: Calculate the pitch angle according to formula (3): Where, is the pitch angle, Δx lf , Δx rf , Δx lr , Δx rr are the vertical displacements of the left front tire, right front tire, left rear tire, and right rear tire relative to the vehicle body, respectively, h lf 、h rf 、h lr 、h rr are the heights of the center of the vehicle's left front tire, right front tire, left rear tire, and right rear tire from the road surface, L fr is the wheelbase of the vehicle.

7. The vehicle fusion positioning method according to claim 1, characterized in that: Determining the wheel speed attitude angle relative to the navigation coordinate system based on the IMU attitude angle, the installation deviation angle, and the pitch angle includes: The wheel speed attitude angle relative to the navigation coordinate system is calculated according to formula (4): Where n represents the navigation coordinate system, b represents the IMU coordinate system, v represents the vehicle coordinate system, and d represents the vehicle speed coordinate system. is the rotation matrix of the vehicle speed coordinate system relative to the navigation coordinate system, that is, the wheel speed attitude angle, is the rotation matrix of the IMU coordinate system relative to the navigation coordinate system, According to the IMU attitude angle, is the rotation matrix of the vehicle coordinate system relative to the IMU coordinate system, Calculated according to the installation deviation angle, is the rotation matrix of the vehicle speed coordinate system relative to the vehicle body coordinate system, It is calculated based on the pitch angle between the vehicle body and the road surface.

8. The vehicle fusion positioning method according to claim 1, characterized in that: Also includes: Obtain the current vehicle's angular velocity, the previous vehicle's position information, the previous IMU's attitude angle, and the IMU's preset non-fixed axis rotation error compensation. Determine the gravitational acceleration based on the vehicle position information at the previous moment, The IMU attitude angle at the current moment is obtained according to the angular velocity, the IMU attitude angle at the previous moment and the preset non-fixed axis rotation error compensation, Correct the IMU attitude angle at the current moment according to the gravity acceleration, or, When a global navigation satellite system GNSS signal is received, the IMU attitude angle at the current moment is corrected using the GNSS signal.

9. A vehicle fusion positioning device, characterized in that: The device comprises: The acquisition module is used to obtain the installation deviation angle between the IMU and the vehicle body, the vertical displacement of each tire of the vehicle relative to the vehicle body, the tire pressure of each tire of the vehicle, the size parameters of each tire of the vehicle at the nominal tire pressure, the wheelbase of the vehicle, and the IMU attitude angle of the IMU relative to the navigation coordinate system when the vehicle body coordinate system and the vehicle speed coordinate system do not coincide with each other. The origin of the vehicle speed coordinate system and the vehicle body coordinate system coincides, and the vehicle speed coordinate system OX d Y d Z d The midpoint of the projection line of the rear axle of the vehicle on the ground is taken as the origin O, and the tangent line of the intersection line of the vehicle symmetry plane and the ground pointing to the axle direction at the origin is taken as the coordinate axis OX d , with the normal line from the ground at the origin pointing to the sky as the coordinate axis OZ d , perpendicular to OY d Z d The straight line pointing to the right side of the vehicle is the coordinate axis OX d ; a first determining module configured to determine a pitch angle of the vehicle body relative to the road surface based on the tire pressure of each tire, the dimensional parameters of each tire at the nominal tire pressure, the vertical displacement of each tire relative to the vehicle body, and the wheelbase of the vehicle; The second determining module is configured to determine the wheel speed attitude angle relative to the navigation coordinate system based on the IMU attitude angle, the installation deviation angle and the pitch angle. The fusion positioning module is used to determine the fusion positioning information of the vehicle at the current moment based on the wheel speed of the vehicle at the current moment, the wheel speed attitude angle and the vehicle position information at the previous moment when no global navigation satellite system GNSS signal is received.

10. A vehicle fusion positioning device, characterized in that: The device comprises: a processor and a memory storing computer program instructions, When the processor executes the computer program instructions, the vehicle fusion positioning method as described in any one of claims 1 to 8 is implemented.

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