512 results about "Yaw moment" patented technology

A method of controlling drift of a vehicle in which the vehicle more easily enters, maintains, releases, and transitions drift behavior, includes determining, by a controller, whether a current driving situation of the vehicle is a drift entry situation or a release situation based on vehicle driving information, and generating a drift index configured to indicate a current degree of drift from a determination result, determining, by the controller, a target yaw moment for left and right speed control depending on a driving situation or a braking situation of the vehicle and target yaw moments for drift assistance control depending on a driver input and a vehicle state in the drift entry situation, based on the vehicle driving information, and generating and outputting, by the controller, a target torque of a motor configured to drive each wheel of the vehicle based on the determined target yaw moments.

The invention is suitable for the technical field of vehicle motion control, and provides a distributed drive-by-wire vehicle motion control method considering parameter robustness, comprising the following steps: establishing a nominal model of system state prediction based on a distributed drive-by-wire vehicle two-degree-of-freedom dynamic model; parameterizing model mismatch into bounded disturbance, constructing a system deviation model and a deviation suppression cost function, and solving a robust state feedback matrix by using an LMI method; based on a tube-based MPC theory, approximately solving a minimum robust invariant set of the nominal model, reconstructing state quantity and control quantity constraints, and solving front and rear wheel turning angles and expected additional yaw moment through rolling optimization; the wheel drive torque is distributed in response to the desired additional yaw moment. According to the control method provided by the invention, the parameter robustness of distributed drive-by-wire vehicle cooperative motion control is improved, and the vehicle handling stability under the model mismatch working condition can be effectively improved.

The invention relates to the technical field of electric vehicle control, and discloses a stability control method and system for an electric vehicle, and the method comprises the steps: collecting vehicle driving data in real time, and dynamically estimating the state parameters of the vehicle through an unscented Kalman filtering algorithm; according to the state parameters of the vehicle, combined with the kinematic model and the foresight trajectory, the expected yawing moment in a short time in the future is calculated, and the longitudinal traction requirement of the vehicle is obtained; and according to the state parameters of the vehicle and the longitudinal traction requirement of the vehicle, the yawing moment and the traction force are decoupled and distributed to the four electric driving wheel ends, and stable control over the electric vehicle is achieved. Compared with a traditional stable control system only based on closed-loop feedback, the stable control system has the advantages that the control response is faster, the yawing intervention is more accurate, and better control performance and vehicle safety are shown under the low-adhesion road surface and high-load working conditions.

The invention discloses a chassis coordination control method and system based on tire side deviation state evaluation, and relates to the technical field of four-wheel steering four-wheel drive vehicle dynamics control. The method comprises the steps that an expected front wheel rotation angle is determined based on an expected steering wheel rotation angle input by a driver, and a front wheel rotation angle is determined; further determining a feed-forward front wheel steering angle, a feed-forward rear wheel steering angle and an additional yaw moment based on feed-forward control and feedback control, determining a first tire slip angle and a second tire slip angle based on a road adhesion coefficient, and further determining a wheel torque control weight, a feedback front wheel steering angle control weight and a feedback rear wheel steering angle control weight; and further determining a driving yaw moment, a feedback front wheel steering angle and a feedback rear wheel steering angle, determining a total longitudinal force based on an expected longitudinal acceleration input by a driver, and performing four-wheel torque distribution based on the total longitudinal force and the driving yaw moment to obtain a four-wheel driving torque. The driving stability of the vehicle under the limiting working condition can be improved.

The invention discloses a reconfigurable distributed driving multi-axis vehicle trajectory tracking method and a carrying device. The method comprises the following steps: acquiring longitudinal and transverse movement speeds and yaw velocity of a vehicle body in real time; acquiring position information and target path information of a vehicle, and matching a trajectory tracking target point; establishing a vehicle three-degree-of-freedom dynamic model for trajectory tracking; according to a longitudinal dynamic model of the vehicle, a sliding mode control method is adopted to solve longitudinal force needed by the whole vehicle, and the effect of tracking the specified speed is achieved; a tracking error model is obtained, and the rotation angle of each wheel and the yaw moment of the whole vehicle are calculated based on a nonlinear model predictive control algorithm; distributing the longitudinal tire force of each wheel according to the definition of the tire adhesion rate and the requirements of the longitudinal force and the yawing moment of the whole vehicle output by the upper-layer controller, and converting the longitudinal tire force into motor torque; and controlling a steering system and a wheel motor of the vehicle to execute the wheel steering angle and torque instruction. The control stability and trajectory tracking precision of the vehicle can be improved.

The invention discloses a heavy commercial vehicle yaw control system with delay compensation and slip suppression. A state sensing unit collects signals and sends data to a yaw control unit and a braking force control unit. The yaw control unit acquires a desired yaw moment and a braking moment. A yaw velocity tracking module calculates a desired yaw velocity. And the wheel slip suppression module obtains a brake torque for avoiding slip through control. The braking force control unit addresses braking force distribution under yaw moment control and wheel slip suppression, and compensates for the delay of the pneumatic brake system. And the braking force cooperative distribution module calculates the expected braking chamber pressure of each wheel according to the required yawing moment and the braking moment. The braking force delay compensation module calculates and predicts the pressure of a braking chamber through a prediction model, and obtains control input of a braking actuator through a PID controller so as to compensate delay. According to the system, the driving safety of the heavy commercial vehicle under the complex road condition is improved through cooperative control.

The invention discloses an automobile stability coordination control method based on reinforcement learning, and belongs to the technical field of electric automobile control, the method comprises the following steps: using a linear two-degree-of-freedom model to obtain an expected yaw velocity and an expected side slip angle; additional yawing moment and a steering angle of a driving rear wheel are obtained through sliding mode control; acquiring the state type of the current vehicle; constructing an intelligent agent and a reward function of reinforcement learning, and continuously training the intelligent agent until the optimal cooperative control coefficients of the additional yaw moment and the steering angle of the active rear wheel are output, so as to realize the cooperative control of the electric vehicle; the reward function includes a steady state reward, a yaw velocity error and side slip angle error reward, a critical steady state reward, and an anti-jitter reward. According to the invention, the steering and yawing moment of the driving rear wheel can be coordinated and controlled, so that the stability and safety of the vehicle are ensured.

The invention discloses a stability control system and method considering time varying and time lag of a steering mechanism, and the system comprises a rotation angle generation module, a reference model module, an error fusion module, a stability control module, and an EKF side slip angle observation module. Wherein the steering angle generation module adopts a model predictive control (MPC) algorithm to track an expected trajectory and generate a front wheel steering angle, and the stability control module adopts a Smith pre-estimation compensation method to design active front wheel steering (Smith-AFS) and direct yawing moment control (DYC) so as to realize the stability control of the intelligent vehicle under the condition that an execution mechanism has time-varying and time-lag. According to the stability control system and method considering the time-varying time-lag of the steering mechanism, the tracking precision of the side slip angle and the yaw velocity is greatly improved, and the time-lag interference problem of a stability controller can be solved.

A vehicle, a vehicle stability control method and apparatus, and a medium. The method comprises: establishing a lateral stability linear model of a vehicle, wherein in the lateral stability linear model, an additional yaw moment is used as a control quantity, both a mass-center sideslip angle and a yaw rate are used as state quantities correlated with a tire lateral force, and the tire lateral force is linearly correlated with a tire sideslip angle within a preset sideslip angle range; using, as a first optimization objective, the objective of the additional yaw moment meeting a target mass-center sideslip angle and a target yaw rate, and constructing a constraint condition of the first optimization objective on the basis of an additional torque capability range of each motor of the vehicle; and using, as a second optimization objective, the objective of enabling the output energy of each motor to be minimum, and decomposing the additional yaw moment into the additional torque of each motor on the basis of the second optimization objective and the first optimization objective having the constraint condition. The vehicle stability control can be realized with the minimum motor energy output, thereby improving the energy-saving effect.

The invention provides a vehicle control method, a vehicle control device and a vehicle. The method comprises the steps that if it is detected that a first wheel of the vehicle is in a slipping state, the torque to be distributed during torque reduction of the first wheel is obtained; and distributing the torque to be distributed to the second wheel, wherein the second wheel is used for representing a wheel on the opposite side of the first wheel; determining a target difference value of the yaw moment of the vehicle corresponding to the torque to be distributed; determining a target steering angle of a rear wheel in the vehicle based on the target difference value of the yaw moment; the rear wheel is controlled based on the target steering angle. According to the method, safe and rapid running of the vehicle can be ensured under the condition that wheels slip.

The invention provides a vehicle transverse control method and system, vehicle-mounted communication equipment and a vehicle, and the method comprises the steps: carrying out the transverse deviation detection of the vehicle, and recognizing whether the vehicle deviates from the driving direction or not based on a transverse deviation detection result; when the driving direction of the vehicle deviates, whether the vehicle is in manual driving control or not is judged; when the vehicle is not in the manual driving control state and an original transverse control system of the vehicle fails, wheel end braking force of the vehicle is redistributed to generate yawing moment, the movement direction of the vehicle is corrected through the yawing moment, and transverse control is conducted on the vehicle; and when the vehicle is not in the manual driving control state and the original transverse control system of the vehicle does not fail, transverse control is conducted on the vehicle through the original transverse control system. The yaw moment is generated by directly redistributing the wheel end braking force, the movement direction of the vehicle is corrected, the movement direction of the vehicle is controllable all the time, it is ensured that the vehicle is kept in the correct driving direction all the time, and transverse collision is avoided.

The invention relates to the technical field of flight control, in particular to an unmanned aerial vehicle single-shot failure control method, system and device and a medium, and the method comprises the steps: single-shot failure control in the take-off stage of an unmanned aerial vehicle, namely, taking-off is interrupted, an engine on the other side is closed, a brake is used, and a rudder and a front wheel are used for carrying out deviation correction control on the unmanned aerial vehicle; single-engine failure control in the air cruise stage of the unmanned aerial vehicle: compensating additional yaw moment brought by a single-side engine through a transverse heading automatic compensation controller and a flight control system together to enable the aircraft to reach a balanced state, and adjusting the heading of the unmanned aerial vehicle to a designed emergency course to complete recovery; the single-shot failure control in the landing stage of the unmanned aerial vehicle comprises the following steps of: keeping the balance of the unmanned aerial vehicle by utilizing a transverse heading automatic compensation controller before landing, immediately closing an engine on the other side after touching the ground, and adopting a rudder and a front wheel to rectify deviation to control and track a ground route. The flight safety of the unmanned aerial vehicle is guaranteed, and the single-shot failure emergency processing capacity of the unmanned aerial vehicle is improved.

The invention discloses a commercial vehicle driving control method considering a load non-uniform distribution characteristic. The method comprises the following steps: acquiring and preprocessing sensor data of a commercial vehicle; estimating yaw disturbance torque caused by uneven load distribution in real time; a robust model prediction controller based on yaw disturbance torque compensation is constructed, and multi-axis coordinated yaw torque meeting the driving stability requirement under the non-uniform load working condition is output; driving force optimization distribution is carried out, and target driving force of each electric wheel is determined; and designing a driving force synchronous tracking controller based on the tire relaxation characteristic model, and outputting the torque of each electric wheel to complete the driving stability control of the commercial vehicle. According to the method, the yaw disturbance torque observer and robust model predictive control are fused, and the disturbance yaw torque is estimated in real time and compensated in a feedforward mode, so that pertinence and fineness are better in the aspect of disturbance suppression; the auxiliary sliding mode control can further improve the robustness of the system in an unknown or rapidly changing external environment.

The invention is applicable to the technical field of distributed driving electric vehicle control, and provides a distributed driving pre-stabilization control system and method based on state estimation, and the system comprises a data acquisition module, a central processing module and a control execution module. The method comprises the following steps: firstly, receiving signals of each sensor, a gyroscope and a vehicle parameter unit; calculating a longitudinal force and a lateral force of a vehicle driving wheel; state parameters of the vehicle are calculated according to the longitudinal force and the lateral force; state trend prediction is carried out through the state trend; according to the predicted future automobile state, pre-stability judgment is carried out through the principle of a phase plane and a yaw velocity threshold value; when the automobile is about to be unstable, needed yaw moment is calculated, a pre-stability control mode is started, four-wheel torque distribution is carried out through a torque vector distribution method, and torque needing to be distributed by four wheels is obtained; and then a torque control instruction is sent to the driving motor through the execution module, so that the four-wheel torque reaches the calculated torque.

The invention relates to a robust cooperative control method for yaw stability of a distributed angle module electrically-driven vehicle. The method comprises the following steps: acquiring driving state data of a corner module vehicle; according to the transverse stability constraint condition and the transverse dynamical model, a nominal control model is constructed, the nominal control model is a part related to the determined parameters in the transverse dynamical model, and the target of the transverse stability constraint condition is that the error of the yaw velocity and the error of the lateral velocity tend to zero; constructing an uncertainty control model, wherein the uncertainty control model is a part related to the uncertain parameters in the transverse dynamic model; driving state data are input into the nominal control model and the uncertainty control model, and yaw moment control parameters are determined; and based on the yaw moment control parameter and the rear wheel steering control parameter, performing stability cooperative control on the angle module vehicle. By adopting the method, the yaw stability of the angle module vehicle can be improved.

The invention belongs to the field of vehicle stability control, and particularly relates to a control method suitable for integration of four-wheel independent drive and active rear wheel steering. Comprising the steps of establishing a whole vehicle dynamics model suitable for controller design, performing stable region division by combining front and rear wheel side slip angle phase planes, setting an ideal yaw velocity and an ideal side slip angle, designing a feedforward and PID feedback integrated controller, performing torque distribution and the like. According to steering wheel rotation angle input, corresponding parameters of the vehicle are combined, the vehicle stability coefficient, the ideal yaw velocity and the side slip angle are calculated, the feedforward and PID feedback integrated controller inputs the calculated rear wheel rotation angle into the controlled vehicle, the calculated additional yaw moment obtains the basic driving moment based on pedal information, and the vehicle stability coefficient, the ideal yaw velocity and the side slip angle are calculated. Torques corresponding to four wheels are input to a controlled vehicle through torque distribution, so that the purpose of integrated control is achieved, and the vehicle handling stability is improved.

The invention provides a transverse stability control method and system during braking of a vehicle on a split road surface, and belongs to the technical field of vehicle transverse stability control. According to the method, the expected braking strength zd is compared with the maximum braking strength zth which can be generated by the whole vehicle on the low-adhesion road surface, and when zd is smaller than or equal to zth, the braking force at the high-adhesion position is restrained, and the difference value between the braking force at the high-adhesion position and the braking force at the low-adhesion position is reduced or even eliminated through the design of the controller; when z dgt; when zth is greater than zth, through the design of a controller, the braking force at the low attachment part is kept at a peak value, the braking force at the high attachment part is regulated and controlled, and meanwhile, the rear wheel turning angle is controlled, so that an additional yawing moment is generated, and the expected yawing moment of the whole vehicle is compensated. The invention further provides a split road surface stability comprehensive risk index, and the stability of the vehicle during braking on the split road surface is comprehensively evaluated. When the vehicle exceeds a steady state boundary, active four-wheel steering intervenes. According to the invention, the transverse stability of the vehicle during braking on the split road surface is effectively improved.

The application discloses a kind of distributed drive electric vehicle stability control method and system, desired centroid side slip angle and yaw angular velocity are calculated as control target according to vehicle dynamics model, actual centroid side slip angle and yaw angular velocity are estimated in real time by Kalman filtering.Further through stability judging law, vehicle state is identified using phase plane method.According to vehicle state, it is divided into: stable domain, coordination domain and non-stable domain.Further control target value and actual value are input into model reference adaptive controller, and the size of additional yaw moment and front wheel angle is respectively solved.The weight size of the two is calculated by the vehicle stability region determined in stability law.Additional front wheel angle can be directly input into vehicle actuator, if direct torque control is needed, additional yaw moment size needs to be input into torque distribution module for real-time solution, and finally left and right wheel torque value of front axle is output to vehicle actuator.

Disclosed in the present application is a torque vectoring control system for an in-wheel-motor four-wheel-drive vehicle. In the torque vectoring control system, a driving style identification module determines the driving style of a driver during the travel of an in-wheel-motor four-wheel-drive vehicle; a vehicle state sensing module acquires a steering wheel angle and a longitudinal vehicle speed in real time, and performs fault state monitoring on the in-wheel-motor four-wheel-drive vehicle; a vehicle motion control module calculates an ideal yaw rate target of the in-wheel-motor four-wheel-drive vehicle; and a torque vectoring control module calculates an additional yaw moment on the basis of the ideal yaw rate target and an actual yaw rate, executes a corresponding fault handling strategy on the basis of a fault state monitoring result, and then performs torque distribution on the basis of the additional yaw moment combined with the fault state monitoring result to generate an additional driving torque and an additional braking torque of each wheel. The present application realizes self-adaptive yaw stability control for drivers having different driving styles.

The invention discloses an unmanned aerial vehicle path planning method and system in an unknown obstacle environment, and particularly relates to the technical field of unmanned aerial vehicle autonomous navigation and path planning. Constructing an observation space containing a relative target position, a speed, an attitude angle, an angular speed and an obstacle; designing a continuous action space comprising total lift force, rolling moment, pitching moment and yawing moment; constructing a multi-dimensional award function fusing a task end award, a distance target award, a forward efficiency award and an obstacle avoidance safety award, and guiding an intelligent agent to optimize a path; on the basis of observation space and reward feedback, an intelligent agent control strategy is continuously optimized through exploration and development of a self-adaptive entropy regularization balance strategy in an SAC algorithm, and collision-free and short-path real-time path planning is achieved.

The embodiment of the invention provides a vehicle steering control method, a controller, a vehicle, a medium and a program product, and the method comprises the steps: obtaining a steering wheel rotation angle and a vehicle longitudinal speed of the vehicle when the vehicle is controlled to steer; according to the steering wheel angle and the vehicle longitudinal speed, target steering control parameters are determined, and control is conducted according to the target steering control parameters; actual steering control parameters of the vehicle are obtained; according to the target steering control parameter and the actual steering control parameter, fast terminal sliding mode control is carried out, and yawing moment and a rear wheel steering angle are generated; according to the yawing moment and the steering angle of the rear wheels, the two first wheels are controlled, and the control stability of the vehicle can be improved through the embodiment of the invention.

The invention relates to the technical field of closed-loop drift control, and particularly discloses a closed-loop drift control method and system for an autonomous vehicle in an uncertain environment, and the method comprises the steps: building a vehicle kinematic model based on a Frenet coordinate system, and constructing an MPC path tracking controller with a preview mechanism; establishing a three-degree-of-freedom vehicle dynamics model with additional yawing moment; the method comprises the following steps: establishing a UniTile-Ctrl tire dynamic model; designing a robust drift controller by combining LQR and integral sliding mode control on the basis of the whole vehicle dynamic model and the tire dynamic model, designing a torque distribution module by taking minimization of distribution error and tire load utilization rate as targets on the basis of ideal rear wheel rotating speed and additional yawing moment output by the robust controller, and outputting a torque distribution model; according to the drifting vehicle tracking control method, closed-loop drifting control can be achieved, the drifting vehicle tracking control performance and robustness are improved, and safety guarantee is provided for limit control over the uncertain road surface of the vehicle.

The invention belongs to the technical field of wind driven generator main bearing test equipment, and discloses a five-degree-of-freedom wind driven generator main bearing test bench for simulating real working conditions, which comprises a loading system, a test system and a driving system. The loading system adopts a sliding bearing loading disc to simulate a hub of the wind driven generator, and adopts a hydraulic cylinder array to simulate five-degree-of-freedom hub loads of three-direction forces including axial force, radial force and vertical force and two-direction moments including pitching moment and yawing moment. The test system adopts a two-point supported tapered roller bearing main shaft system to simulate the main shaft configuration of the wind driven generator, and can be independently disassembled to replace the model of a test bearing. The driving system adopts a variable-frequency and variable-speed motor, the rotating speed range is 0-200 rpm, and the requirements of various working conditions such as frequent start and stop, performance tests and strengthening tests can be met. According to the invention, through multi-dimensional load loading and multi-working-condition simulation, a key platform is provided for reliability test and failure mechanism research of the wind power main bearing.

A vehicle and a control method and apparatus therefor, a storage medium, and a computer program product, relating to the technical field of vehicles. The control method for a vehicle comprises: correcting an ideal yaw rate on the basis of desired steering characteristic information; obtaining an additional yaw moment on the basis of an ideal sideslip angle, the corrected ideal yaw rate, and an actual sideslip angle and an actual yaw rate of a vehicle; and performing torque distribution on the basis of the additional yaw moment. In the method, the ideal yaw rate is corrected on the basis of the desired steering characteristic information, so that, on the basis of the ideal sideslip angle, the corrected ideal yaw rate, and the actual sideslip angle and the actual yaw rate of the vehicle, variable steering characteristics of the vehicle are achieved by means of torque control, thereby enabling the vehicle to obtain higher steering sensitivity.

The invention discloses an intelligent automobile transverse control method based on sensor measurement reconstruction under network attacks, and relates to automobile intelligent safety and automatic driving. A model prediction control MPC controller based on sensor measurement reconstruction is constructed, and accurate control over transverse movement of the vehicle is achieved. The system monitors sensor data in real time, detects sensor data abnormity caused by network attack, starts a measurement reconstruction mechanism, and corrects the data by using a redundant sensor or an algorithm model. A lower-layer torque optimal distribution controller is designed, the controller intelligently adjusts output torques of four hub motors according to expected yaw moment output by an upper-layer MPC and vehicle state information, so that accurate control over the yaw moment of the vehicle is achieved, transverse tracking errors are reduced, and the driving stability and the dynamic performance of the vehicle are improved. A transverse cooperative control rule is provided, and comprehensive optimization of transverse control of the vehicle is achieved by coordinating work of an upper-layer MPC controller and work of a lower-layer torque optimization distribution controller.

This invention is applicable to the field of vehicle stability control technology and provides a coordinated stability control method and system for distributed, drive-by-wire vehicles. The method comprises the following steps: constructing a vehicle dynamics model; collecting vehicle state information based on a state recognition layer and a driving intention recognition layer, calculating and correcting the ideal yaw rate and ideal center-of-mass sideslip angle; allocating control variable weights using a KDPC algorithm; calculating the values ​​of the vehicle's control variables, namely, the rear wheel angle and the additional yaw moment; and allocating wheel drive torque based on the vehicle force, the additional yaw moment, the ratio of front and rear axle loads, the wheel radius, and the wheelbase. Through its electronic and dynamic control strategy, the invention achieves multi-dimensional advantages in flexibility, stability, energy efficiency, and intelligence, extending the vehicle chassis' extreme performance and vehicle handling stability.

The present invention discloses a four-wheel steering control method for a distributed drive electric vehicle, which relates to the technical field of vehicle control. The front wheel steering angle δ is output by a driver model f , the throttle pedal opening α p , and the throttle pedal opening change rate Δα p . The ideal center-of-mass side slip angle β d and the ideal yaw angular velocity γ d are obtained through the two-degree-of-freedom dynamics equation of the front-wheel-steering vehicle. Then, based on the characteristics of the distributed drive torque vector control method and the rear-wheel active steering control method, and in combination with the actual center-of-mass side slip angle β and the actual yaw angular velocity γ of the vehicle, the vehicle target motion state tracking under different working conditions is carried out, and the additional yaw moment ΔM z and / or the rear wheel steering angle δ r are obtained. Finally, the coordinated control of the vehicle is realized through the four-wheel steering distributed drive vehicle model. While considering the control effect, the present invention takes into account the driving habits and driving needs of the driver to the greatest extent, not only improving the overall performance of the vehicle control system, but also ensuring the sensitivity, maneuverability and stability of the vehicle.

The invention relates to the technical field of vehicles, in particular to a distributed driving vehicle transverse stability control method and device, a vehicle and a medium, and the method comprises the steps that the state parameter, the road adhesion coefficient and the actual yaw velocity of the current vehicle are acquired; calculating an expected yaw velocity of the vehicle based on the state parameter and the road adhesion coefficient; the expected yaw moment of the vehicle is calculated based on the expected yaw velocity and the actual yaw velocity, the wheel vertical load of the vehicle is obtained, and according to the expected yaw moment and the wheel vertical load, the driving torques, meeting the transverse stability, of the multiple motors of the vehicle are determined; and a plurality of motors of the vehicle are controlled to work based on the driving torque meeting the transverse stability. Therefore, the driving force of the wheel corresponding to each motor is always matched with the available road surface adhesive force, the utilization of the overall adhesive force is maximized, and the transverse stability of the vehicle is ensured and the loss of the longitudinal speed of the vehicle can be reduced through the control of the driving torque on the yawing moment.

The invention provides a vehicle control method and device, a controller and a vehicle, and the method comprises the steps: obtaining an expected yaw velocity, an actual yaw velocity, a front axle steering angle and a rear axle steering angle in a vehicle turning rotation adjustment process; determining a target yaw moment according to a difference value between the actual yaw velocity and the expected yaw velocity; according to the target yawing moment, the front axle steering angle, the rear axle steering angle, the number of motors of the front axle and the number of motors of the rear axle, the front axle longitudinal moment and the rear axle longitudinal moment are determined, and the total number of the number of the motors of the front axle and the number of the motors of the rear axle is larger than 1 and smaller than 4; and controlling the vehicle to steer according to the front axle longitudinal moment and the rear axle longitudinal moment. Through the method, a precise control mode of turning around in situ is provided for the vehicle with double motors and three motors.

The invention belongs to the technical field of civil aviation special vehicles, and particularly introduces a three-wheel failure emergency driving method suitable for four-wheel independent driving and steering of a civil aircraft tractor. The method comprises the following emergency driving modes: 1, a four-wheel independent steering method; 2, a single-wheel driving steering method; and 3, a wheel braking method. The four-wheel independent steering method is used for independently controlling the internal and external corner relation between wheels. The single-wheel driving steering method is used for resolving the turning angles of four wheels; the wheel braking method is used for limiting the wheel braking force. In a traditional vehicle, after three wheels fail, the vehicle cannot run, the whole vehicle generates yawing moment deviation, and the rear two wheels cannot steer, so that the vehicle cannot advance. However, on a full-vector automobile, when the automobile runs straight, the steering directions of the other three wheels can be kept horizontal by enabling the working driving wheels to penetrate through the center of the automobile, so that the yawing moment is eliminated, and stable straight running is achieved.