# US 2021/0276539 A1 · Method and apparatus for simulating vehicle, and medium > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0276539 A1 - Document ID: US20210276539A1 - Status: Published application - Kind: A1 - Application number: 17/189,899 - Filed: 2021-03-02 - Published: 2021-09-09 - Earliest claimed: 2020-03-03 - Assignees: Beijing Baidu Netcom Science Technology Co., Ltd. - Applicants: Beijing Baidu Netcom Science and Technology Co., Ltd. - Inventors: Yinong TAN; Xiao CUI; Dingfeng GUO; Zhenguang ZHU - Web page: https://patentgrep.com/patent/US20210276539A1 ## CPC - B60W 30/02: Control of vehicle driving stability - G06F 30/15: Vehicle, aircraft or watercraft design - B60W 10/04: including control of propulsion units - B60W 10/18: including control of braking systems - B60W 40/10: related to vehicle motion - G06F 30/20: Design optimisation, verification or simulation (optimisation, verification or simulation of circuit designs G06F30/30) - B60W 2520/26: Wheel slip - B60W 2530/20: Tyre data - B60W 2540/10: Accelerator pedal position - B60W 2540/12: Brake pedal position - B60W 2540/16: Ratio selector position - B60W 2540/18: Steering angle - Y02T 90/00: Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation - B60W: CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract The disclosure discloses a method and an apparatus for simulating a vehicle. The detailed implementation includes: determining, by a tire dynamics module, a tire translational force at a current moment based on a control instruction issued by an upper planning module and motion data of a vehicle body and a tire normal load outputted by a vehicle body dynamics module at a previous moment; and determining, by the vehicle body dynamics module, motion data of the vehicle body and a tire normal load at the current moment based on the control instruction and the tire translational force at the current moment, the motion data of the vehicle body at the current moment being used for vehicle simulation, and the tire normal load at the current moment being used to determine a tire translational force at a next moment. ## Claims ### Claim 1 A method for simulating a vehicle, comprising: determining, by a tire dynamics module, a tire translational force at a current moment based on a control instruction issued by an upper planning module and motion data of a vehicle body and a tire normal load outputted by a vehicle body dynamics module at a previous moment; and determining, by the vehicle body dynamics module, motion data of the vehicle body and a tire normal load at the current moment based on the control instruction and the tire translational force at the current moment, the motion data of the vehicle body at the current moment being used for vehicle simulation, and the tire normal load at the current moment being used to determine a tire translational force at a next moment. ### Claim 2 (depends on 1) The method of claim 1, after determining the motion data of the vehicle body and the tire normal load at the current moment, further comprising: sending, by the vehicle body dynamics module, the motion data of the vehicle body at the current moment to the upper planning module, to enable the upper planning module performing the vehicle simulation based on the motion data of the vehicle body at the current moment. ### Claim 3 (depends on 1) The method of claim 1, after determining the motion data of the vehicle body and the tire normal load at the current moment, further comprising: sending, by the vehicle body dynamics module, the tire normal load at the current moment to the tire dynamics module; and determining, by the tire dynamics module, the tire translational force at the next moment based on the tire normal load at the current moment. ### Claim 4 (depends on 1) The method of claim 1, wherein the control instruction comprises at least one of: a gear position, a driving pedal opening, a braking pedal opening, and a steering angle of a steering wheel. ### Claim 5 (depends on 4) The method of claim 4, before determining the tire translational force at the current moment based on the control instruction and the motion data of the vehicle body and the tire normal load outputted by the vehicle body dynamics module at the previous moment, further comprising: converting, by the tire dynamics module and/or the vehicle body dynamics module, the control instruction into a vehicle control parameter based on a preset calibration table of control parameters, the vehicle control parameter comprising driving torque and/or braking torque. ### Claim 6 (depends on 5) The method of claim 5, wherein determining the tire translational force at the current moment based on the control instruction issued by the upper planning module and the motion data of the vehicle body and the tire normal load outputted by the vehicle body dynamics module at the previous moment comprises: determining a tire motion parameter at the current moment based on the driving torque, the braking torque, a tire rotation radius, a tire pressure, and a velocity of the vehicle body and the tire normal load outputted by the vehicle body dynamics module at the previous moment; determining a tire longitudinal sliding rate at the current moment based on the tire rotation radius, the tire motion parameter and the velocity of the vehicle body outputted by the vehicle body dynamics module at the previous moment, and determining a tire longitudinal force at the current moment based on the tire longitudinal sliding rate and the tire normal load outputted by the vehicle body dynamics module at the previous moment; and determining a tire lateral slip angle at the current moment based on a tire wheelbase, the tire motion parameter and the vehicle body velocity outputted by the vehicle body dynamics module at the previous moment, and determining a tire lateral force at the current moment based on the tire lateral slip angle and the tire normal load outputted by the vehicle body dynamics module at the previous moment, wherein the tire translational force comprises the tire longitudinal force and the tire lateral force. ### Claim 7 (depends on 5) The method of claim 5, wherein determining the motion data of the vehicle body and the tire normal load at the current moment based on the control instruction and the tire translational force at the current moment comprises: determining an air resistance and an air resistance torque based on a wind speed and a tire wheelbase; determining an acceleration of the vehicle body and a yaw angle acceleration of the vehicle body based on a vehicle rotating inertia, the air resistance, the air resistance torque and the tire translational force at the current moment outputted by the tire dynamics module; determining the tire normal load based on the acceleration of the vehicle body, the yaw angle acceleration of the vehicle body, the tire wheelbase, the air resistance and the air resistance torque at the current moment; and determining a motion parameter of the vehicle body based on the acceleration of the vehicle body and the yaw angle acceleration of the vehicle body, wherein the motion parameter of the vehicle body comprises at least one of: the acceleration of the vehicle body, the velocity of the vehicle body, a position of the vehicle body, a yaw angle of the vehicle body, a yaw angle velocity of the vehicle body, and the yaw angle acceleration of the vehicle body. ### Claim 8 (depends on 2) The method of claim 2, before sending, by the vehicle body dynamics module, the motion data of the vehicle body at the current moment to the upper planning module, further comprising: transforming, by the vehicle body dynamics module, the motion data of the vehicle body at the current moment from a first coordinate system employed by the vehicle body dynamics module to a second coordinate system employed by the upper planning module. ### Claim 9 An apparatus for simulating a vehicle, comprising: one or more processors; a memory storing instructions executable by the one or more processors; wherein the one or more processors are configured to: determine a tire translational force at a current moment based on a control instruction issued by an upper planning module and motion data of a vehicle body and a tire normal load outputted by a vehicle body dynamics module at a previous moment; and determine motion data of the vehicle body and a tire normal load at the current moment based on the control instruction and the tire translational force at the current moment, the motion data of the vehicle body at the current moment being used for vehicle simulation, and the tire normal load at the current moment being used to determine a tire translational force at a next moment. ### Claim 10 (depends on 9) The apparatus of claim 9, wherein the one or more processors are configured to: send the motion data of the vehicle body at the current moment to the upper planning module, to enable the upper planning module performing the vehicle simulation based on the motion data of the vehicle body at the current moment. ### Claim 11 (depends on 9) The apparatus of claim 9, wherein the one or more processors are configured to: send the tire normal load at the current moment to the tire dynamics module; and determining the tire translational force at the next moment based on the tire normal load at the current moment. ### Claim 12 (depends on 9) The apparatus of claim 9, wherein the control instruction comprises at least one of: a gear position, a driving pedal opening, a braking pedal opening, and a steering angle of a steering wheel. ### Claim 13 (depends on 12) The apparatus of claim 12, wherein the one or more processors are configured to: convert the control instruction into a vehicle control parameter based on a preset calibration table of control parameters, the vehicle control parameter comprising driving torque and/or braking torque. ### Claim 14 (depends on 13) The apparatus of claim 13, wherein the one or more processors are configured to: determine a tire motion parameter at the current moment based on the driving torque, the braking torque, a tire rotation radius, a tire pressure, and a velocity of the vehicle body and the tire normal load outputted by the vehicle body dynamics module at the previous moment; determine a tire longitudinal sliding rate at the current moment based on the tire rotation radius, the tire motion parameter and the velocity of the vehicle body outputted by the vehicle body dynamics module at the previous moment, and determine a tire longitudinal force at the current moment based on the tire longitudinal sliding rate and the tire normal load outputted by the vehicle body dynamics module at the previous moment; and determine a tire lateral slip angle at the current moment based on a tire wheelbase, the tire motion parameter and the vehicle body velocity outputted by the vehicle body dynamics module at the previous moment, and determine a tire lateral force at the current moment based on the tire lateral slip angle and the tire normal load outputted by the vehicle body dynamics module at the previous moment, wherein the tire translational force comprises the tire longitudinal force and the tire lateral force. ### Claim 15 (depends on 13) The apparatus of claim 13, wherein the one or more processors are configured to: determine an air resistance and an air resistance torque based on a wind speed and a tire wheelbase; determine an acceleration of the vehicle body and a yaw angle acceleration of the vehicle body based on a vehicle rotating inertia, the air resistance, the air resistance torque and the tire translational force at the current moment outputted by the tire dynamics module; determine the tire normal load based on the acceleration of the vehicle body, the yaw angle acceleration of the vehicle body, the tire wheelbase, the air resistance and the air resistance torque at the current moment; and determine a motion parameter of the vehicle body based on the acceleration of the vehicle body and the yaw angle acceleration of the vehicle body, wherein the motion parameter of the vehicle body comprises at least one of: the acceleration of the vehicle body, the velocity of the vehicle body, a position of the vehicle body, a yaw angle of the vehicle body, a yaw angle velocity of the vehicle body, and the yaw angle acceleration of the vehicle body. ### Claim 16 (depends on 10) The apparatus of claim 10, wherein the one or more processors are configured to: transform the motion data of the vehicle body at the current moment from a first coordinate system employed by the vehicle body dynamics module to a second coordinate system employed by the upper planning module. ### Claim 17 A non-transitory computer readable storage medium having computer instructions stored thereon, wherein the computer instructions are configured to cause a computer to execute a method for simulating a vehicle, and the method comprises: determining, by a tire dynamics module, a tire translational force at a current moment based on a control instruction issued by an upper planning module and motion data of a vehicle body and a tire normal load outputted by a vehicle body dynamics module at a previous moment; and determining, by the vehicle body dynamics module, motion data of the vehicle body and a tire normal load at the current moment based on the control instruction and the tire translational force at the current moment, the motion data of the vehicle body at the current moment being used for vehicle simulation, and the tire normal load at the current moment being used to determine a tire translational force at a next moment. ### Claim 18 (depends on 17) The non-transitory computer readable storage medium of claim 17, after determining the motion data of the vehicle body and the tire normal load at the current moment, the method further comprising: sending, by the vehicle body dynamics module, the motion data of the vehicle body at the current moment to the upper planning module, to enable the upper planning module performing the vehicle simulation based on the motion data of the vehicle body at the current moment. ### Claim 19 (depends on 17) The non-transitory computer readable storage medium of claim 17, after determining the motion data of the vehicle body and the tire normal load at the current moment, the method further comprising: sending, by the vehicle body dynamics module, the tire normal load at the current moment to the tire dynamics module; and determining, by the tire dynamics module, the tire translational force at the next moment based on the tire normal load at the current moment. ### Claim 20 (depends on 17) The non-transitory computer readable storage medium of claim 17, wherein the control instruction comprises at least one of: a gear position, a driving pedal opening, a braking pedal opening, and a steering angle of a steering wheel.