172results about How to "Improve active safety" patented technology

The invention proposes a lane keeping assist system and a lane keeping assist method. The method comprises the steps of comprehensively detecting a people-vehicle-road driving environment through a lane environment detection module, a vehicle state detection module, a driver driving state detection module and a vehicle and road surface rolling friction coefficient detection module; calculating a corresponding detection signal through a lane keeping control module; judging whether a vehicle deviates from a lane or not; performing transverse lane return-to-center control through cooperative control of an electric power steering system (EPS) and an electronic stability program (ESP), and keeping a longitudinal safety distance through ESP control; and giving an alarm for reminding. Through the technical scheme provided by the invention, the driving safety of vehicle driving is remarkably improved; and the lane keeping is realized through the cooperative control of the EPS and the ESP, so that on the premise of ensuring the driving safety of the vehicle, the working comfort of the lane keeping assist system can be improved to the maximum extent.

The invention relates to a method for pre-estimating vehicle trace and evaluating lane deviation, for overcoming the defect of the existing technique not fully reflecting true behavioral characteristic of a driver, announcing a method for evaluating the danger of lane deviation based on behavioral simulation of a driver, using the image sensor-collected lane mark line information of front road and combining the vehicle sensor-provided information such as automobile speed, acceleration, and turning state, to simulate the foreseeing action of the driver (i.e. as driving, the driver controls the present driving of the automobile according to the front road information), forecasting an expected running trace of the automobile in a future period of time, and evaluating the danger of lane deviation with respect to the relative position of the expected running trace and the front road mark lines, thus judging if a lane deviation accident will happen. If the danger of the lane deviation exceeds a certain threshold value, it can give out lane deviation early warning information to the driver by sound and vehicle LCD.

The invention discloses a lane line predicating and early warning method suitable for a city road. According to the method, firstly, down sampling is performed on a collected road image, a detection region of interest is set and grayed, filtering enhancement is performed on the region of interest, edge detection is performed through a Canny operator, binarization is performed on the image after edge detection, then the image is mapped on a Hough plane, and lane lines are extracted through improved Hough conversion; then, parameters of the lane line are predicated by the adoption of a classical Kalman filtering algorithm, a region of interest is established, and the lane lines in the region of interest are fitted through a least square method to obtain the optimal predication value; finally, road surface information and current position information of automobiles are combined to establish a lane line departure warning model based on transverse distance, and therefore departure warning is achieved. The recognition method for the lane lines is good in real-time performance and robustness, according to the lane line departure warning model, calculation is easy, and warning is accurate.

The invention relates to a trajectory tracking control method and a control device for a driverless vehicle. The control method comprises that error of present driving trajectory and a reference trajectory of a vehicle is calculated by a data preprocessor, a target performance indicator function which is corresponding to the present driving model is obtained simultaneously; an upper layer controller predicts driving states of the vehicle over a period of time through a vehicle dynamics model; transition switch is conducted to function parameters according to switching control algorithm, and a performance indicator function at present sampling time is obtained; optimal controlled quantity of present time is calculated by considering performance requirement constraint conditions at the same time according to predicted driving states and the performance indicator function; a lower layer controller calculates throttle opening, braking pedal pressure and steering wheel turning angle according to the optimal controlled quantity; and the control device comprises the data preprocessor, the upper layer controller and the lower layer controller. Compared with the prior art, the trajectory tracking control method and the control device for the driverless vehicle have the advantages of being good in control effect, high in practicability, capable of improving stability and safety of vehicles and the like.

The invention relates to a driving / braking system of an independent four-wheel electric automobile, comprising a working condition detection device, a control device, a drive motor driver and a braking device driver, The working condition detection device respectively detects various working condition signals of the electric automobile; the control device processes and calculates the working condition signals to obtain driving control signals and / or braking control signals which correspond to wheels of the electric automobile; and the drive motor driver and the braking device driver respectively control the output of a drive motor and a braking device which respectively correspond to the wheels of the electric automobile according to the driving control signals and / or the braking control signals. The invention can flexibly and reasonably distribute the driving force and the braking force according to working conditions and realize the initiative safety driving / braking of the independent four-wheel electric automobile.

A lane robust identification method for warning departure is that first conducts conditional edge detection on the left and right local windows, and constructs the corresponding gradient direction map. Then, according to the histogram processing method, the gradient direction range of lane edge points on every local window. Aiming at the continuity features of direction and space of lane edge points, the filtering algorithm of the candidate and effect point collection is put forward and every window is filtered. Finally, according to the established effective point collection corresponding to each window, the rapid and accurate extraction of lane symbol is realized though the Kalman filter method based on scalar processing.

The invention relates to a fish streaming based non-signal intersection vehicle-vehicle cooperation control system and belongs to the field of vehicle control. A sensing positioning module of the system comprises an environment sensing portion and a navigation positioning portion and specifically comprises a DGPS positioning device, an inertial navigation system, a radar device and a sensor. A motion control module comprises a motion controller, a driver, an actuator, a transmission part and a controlled part. A wireless communication module consists of a transmitting-receiving device. A human-computer interaction interface comprises a processor, a display unit, an input unit, a communication interface and a data storage unit. A power management and control module comprises a storage battery and a level conversion unit. A route planning module adopts global route planning and is provided with an electronic map. A decision control module comprises a central processing unit, an information processing unit and a storage unit. Compared with the prior art, the fish streaming based non-signal intersection vehicle-vehicle cooperation control system has the advantages of being used for an unmanned vehicle, being provided with a wireless communication module and being high in active safety and road utilization rate.

The invention relates to a monitoring and evaluation method of driving behavior risk degrees and belongs to the technical field of automobile active safety. The method includes that steering wheel rotating angles, vehicle speed, longitudinal acceleration and transverse acceleration are real-timely collected; the real-timely collected data are arranged to form a data sequence in chronological sequence; driving risk degrees of acceleration, braking, overspeed, lave maintaining and lane changing are monitored and evaluated respectively according to vehicle state parameter and driver operation parameter information; comprehensive monitoring and evaluation of total driving risk degree at current moment is performed according to each risk degree index that is obtained in time window wide range so that a comprehensive monitoring and evaluation value at the current moment is obtained. Communication of the obtained comprehensive monitoring and evaluation value with a driver is achieved through an on-line real-time early warning man-machine interaction mode, and thereby, purposes of improving driving safety qualities and reducing road traffic accidents can be achieved.

The invention discloses a hybrid power car braking coordinated control system and a control method thereof, aiming at overcoming the problem that regenerative braking moment and hydraulic braking moment of a hybrid power car in the prior art can not be controlled in a cooperative way. The system comprises an electronic braking maneuver subsystem, a coordinating controller (29), a hydraulic braking moment regulating subsystem and a regenerative braking moment subsystem; wherein, the coordinating controller (29) is respectively and electrically connected with the electronic braking maneuver subsystem, the hydraulic braking moment regulating subsystem and the regenerative braking moment subsystem. The coordinating controller (29) comprises a power control circuit (63), a memory (64), a coordinating controller slot (65), a sensor input signal processing circuit (67), a CAN signal processing circuit (68) and a central processing unit (CPU) (69) which is connected with all the parts by adopting a circuit connecting line (70). The invention also provides a method for coordinating and controlling the regenerative braking moment and the hydraulic braking moment.

The circular ball type electric booster steering device has, except screw, nut, gear sector, steel ball and other mechanical parts, torque sensor, boosting motor, decelerating mechanism, electronic controller unit, etc. The electronic controller unit determines the target current of the motor based on the steering disc torque and the vehicle speed to complete the feedback tracking control of the motor current. The decelerating mechanism has input connected to the motor and output connected to the screw or gear sector shaft in the circular ball steering unit. The present invention has saving in energy, provides proper power force fitting different running conditions, and has less parts, light weight, compact structure and high automation.

The invention provides a vehicle door opening early warning auxiliary system and belongs to the field of vehicle safety. The vehicle door opening early warning auxiliary system comprises a rearview camera used for detecting pedestrian information and transmitting the pedestrian information to a processing unit through a CAN bus, a radar probe used for detecting vehicle information and transmitting the vehicle information to the processing unit through the CAN bus, the processing unit used for calculating the received vehicle information and the received pedestrian information, judging whether collision danger exists in the door opening process or not and sending out a command to a vehicle body control module and further used for receiving information of an owned vehicle, making a judgment and sending out a command for activating / closing the vehicle door opening early warning auxiliary system, and the vehicle body control module used for receiving the command of the processing unit and starting / stopping the vehicle door opening early warning auxiliary system or sending out an alarm. By the adoption of the vehicle door opening early warning auxiliary system, various motor vehicles or pedestrians can be accurately and effectively detected, and the collision danger caused by the fact that a driver is distracted when opening a door is avoided.

The invention relates to a regenerative brake and hydraulic locking-proof integrated control system of a hybrid vehicle. This integrated control system includes regenerative brake control subsystem and hydraulic braking control subsystem. Two control subsystems are not only independently mutual but also unified each other.Independently is that the hydraulic pressure is controlled by the hydraulic braking control subsystem according to the on-position of wheel without restriction of regenerative brake control subsystem operating status, in the like manner, the regenerative brake moment of front axle is also controlled by regenerative brake control subsystem according to the on-position of wheel without restriction of hydraulic control subsystem operating status. Unification of the two brake control subsystems is that the two control subsystems are coordinating and unifying on acting effect, which can realize harmonious unification on energy recovery and locking prevention. The regenerative brake function of the performance motor of high limit on guaranteeing automobile braking safety and smooth-going nature basis has mainly been solved in the invention, which improves the capacity usage ratio and the economy of car load.

The invention discloses a vehicle steer-by-wire device with a redundant mechanism, and a control method of the vehicle steer-by-wire device. The vehicle steer-by-wire device comprises a steering manipulation mechanism, a steering execution mechanism, a first clutch device and a controller; the first clutch device is arranged at the rear end of a steering coil column, and used for connecting or disconnecting the steering manipulation mechanism and the steering execution mechanism; the controller controls the steering manipulation mechanism and the steering execution mechanism; and the steeringexecution mechanism comprises a main motor, a rack assisted steering transmission mechanism connected with the main motor, an auxiliary motor, and a pinion electric assistance transmission mechanism connected with the auxiliary motor. Through mechanical disconnecting of the steering execution mechanism and the steering manipulation mechanism, and redundant design of the steering execution mechanism, the reliability of a steering system for high-grade automatic driving is improved, and high-safety design of the steer-by-wire system is achieved.

The invention provides an electric power steering system. The system comprises a signal acquisition unit, a control unit and an execution unit, wherein the control unit is used for receiving a signal output by the signal acquisition unit in real time, judging whether to enter an active steering mode or an auxiliary steering mode according to the signal, transmitting a command to the execution unit according to the signal and controlling the execution unit to act correspondingly. The invention also provides an automobile using the electric power steering system and a method for controlling the steering of a vehicle based on the electric power steering system. According to the system, the method and the automobile, an auxiliary steering control function, an aligning power control function, an aligning damping control function and other functions of the conventional electric power steering system can be realized, ambient environment information of the vehicle can be detected, and an active steering control function can be realized under an emergent working condition, so that traffic accidents can be effectively prevented.

The invention relates to a pedestrian intention recognition method based on graph convolution. The video image of road environment is captured by a forward-looking camera system mounted on a vehicle.Pedestrian detection and pedestrian human key points extraction are carried out on the image, and the adjacency matrix is constructed to represent the connection information of pedestrian human key points based on graph theory. The bottom feature is extracted from coordinate information and adjacency matrix representation of key points by graph convolution algorithm, and the bottom feature is extracted and time series analyzed by depth convolution neural network and depth loop neural network. Based on the data set of pedestrian intention constructed by manual labeling method, the parameters ofthe model are optimized to realize the classification and recognition of pedestrian intention. The invention effectively utilizes the high-level semantic feature of the key point information of the pedestrian human body, so that the automobile advanced driving assistance system has the ability to understand the pedestrian behavior intention.

The invention discloses a pedestrian anti-collision early warning method based on recognition of the braking and accelerating intention of a driver. The method comprises the following steps: i, experimental data are collected for first-time off-line training of a hidden Markov model (HMM); ii, experimental data are collected for second-time off-line training of the HMM; iii, a data signal about the intention of the driver to avoid collisions with pedestrians is recognized; iv, data analysis is conducted in combination with an infrared human body induction data signal after the data signal about the intention of the driver to avoid collisions with the pedestrians is recognized, and different types of early warning processing are conducted. According to the pedestrian anti-collision early warning method based on recognition of the braking and accelerating intention of the driver, the pedestrians and vehicles serve as a system for studies, a corresponding early warning is given to the driver by means of analyzing the manipulative behavior and strategy which the driver may take when the pedestrians are in front of a car which the driver is driving and judging whether a risk exists according to the driving behavior and intention of the driver, and the early warning is given when the driver conducts wrong driving operation, for example, the driver treads on an accelerator pedal by mistake. As a result, the safety of the pedestrians is effectively protected, and the active safety performance of the car is improved.

The invention relates to a reinforced vehicles ABS system for improving the turning-breaking lateral stability, which belongs to the braking locking-prevention system for improving the turning-braking lateral stability of vehicles; basing on the angle of automobile dynamics, with the consideration of the driving intentions of drivers, the system aims at improving the lateral stability of the vehicles under braking-turning working condition. By a vehicle linear two freedom degree model, the system estimates the driving intentions of drivers, and with the consideration of the deviations between the actual motion states of the vehicles and the expected motion states of the drivers under the working condition of turning-braking, the system judges the tendency of overturning or deficient turning of the vehicles and changes dynamically the ABS sliding rate work intervals between lateral wheels and medial wheels under the condition that the braking efficiency of vehicles is ensured, therefore the produced difference of braking force can lead the vehicles to a stable status rapidly, thus avoiding the dangerous working conditions of whipping and sideslip, and the like, and greatly improving the lateral stability of the vehicles under the working condition of turning-braking.

The invention provides a charging system and method for a charger of an electric car. The charging system comprises a DC module and a charger management system (CMS), wherein the charger management system (CMS) comprises a charger battery management system (CBMS) and a charger charging management system (CCMS); the charger battery management system (CBMS) is connected with the charger charging management system (CCMS) and the DC module through a CAN bus 1; the charger battery management system (CBMS) is connected with battery management systems (BMS) of the car through CAN buses 2; according to collected data like the charging voltage and current of the battery management systems (BMS) of the car and the charger, the charger is converted into an active charging mode from a passive charging mode, logic computation is carried out according to a certain strategy, more reasonable charging voltage and charging current are output within the demand range of the battery management systems (BMS), and unsafe hidden dangers of the conventional charger due to the passive charging mode are eliminated.

The invention relates to the field of electromechanical systems and motor vehicle application, and in particularly relates to a 5-ton-class circulating ball type dual-mode electric power steering device. The electric power steering device comprises a steering device housing assembly, an input shaft and screw assembly, a sector shaft assembly, a supporting base assembly, a turbine, a worm, an inner end cap assembly, a rotating angle and torque sensor, an outer end cap assembly, a plum connecting sleeve assembly and a motor assembly. A motor serves as a power source; power is transmitted to the input shaft and screw assembly via a worm gear and the worm, and the input shaft and screw assembly outputs torque and angle displacement via a sector shaft. The 5-ton-class circulating ball type dual-mode electric power steering device has two control modes of angle (position) and torque (assisting power).

The invention relates to an active anti-collision safety system of an automobile and a control method thereof. Compared with the prior art, the active anti-collision safety system integrates monitoring, early warning and active anti-collision functions, and monitors the safety of the automobile in the whole course. Three modes including a monitoring mode, an early warning mode and an active anti-collision mode are provided. The automobile ensures self safety and exchanges safety information with surrounding vehicles on a real-time basis. Under the early warning mode and the active anti-collision mode, alarming information is sent to the surrounding vehicles to prevent or alleviate collision, minimize the danger and loss of an accident and maximize safety.

The invention discloses an intelligent automobile assistant driving system and method based on a real-time wireless communication network. A CPU (central processing unit) used for control and coordination nodes based on Zigbee wireless communication are set at a road traffic junction position; data processing modules, first memories, speed sensors, GPS (global positioning system) coordination positioning modules, alarms and routers based on the Zigbee wireless communication are arranged on automobiles; a real-time network is established by the coordination nodes so as to realize the sharing of data in the network; any automobile in the network can receive running state information of other automobiles in the network in real time; the data of ambient automobiles are processed and analyzed by the automobile-mounted data processing modules, and with the combination of the change of the self-automobile running state, the alarm judgment is carried out, and the alarm is started when the alarm is judged to be required to be given out. The intelligent automobile assistant driving system and method based on the real-time wireless communication network are easy to implement, high in practical applicability, low in manufacturing cost, high in security and good in real-time capability.

The invention relates to a performance testing device of a carbon dioxide refrigeration compressor for trans-critical and sub-critical refrigeration systems. The prior art is improved in the way thata component for pressure regulation and pressure reduction is connected between a compressor exhaust opening and an exhaust flowmeter in parallel; a safety valve component A is arranged on an oil separator; a safety valve component B is arranged on a condenser; a safety valve component C is arranged on a liquid reservoir; a subcooler is connected between a shutoff valve C of an outlet of the liquid reservoir and an electromagnetic valve in series; a safety valve component D is arranged on the subcooler; a refrigerant filling and recovering storage tank is connected between an inlet of a mass flowmeter and an outlet of a shutoff valve E in parallel; a recovering shutoff valve and a recovering electromagnetic valve are arranged at the position of an inlet of the refrigerant filling and recovering storage tank, a filling shutoff valve and a filling electromagnetic valve are arranged at the position of an outlet of the refrigerant filling and recovering storage tank, and a safety valve component E is arranged on the refrigerant filling and recovering storage tank; and a safety valve component F is arranged on a gas cooler. In the invention, most of parts can adopt products of the conventional pressure resisting grade, thereby solving the problem of higher pressure of the whole system, reducing the cost and improving the safety of the system.

The invention discloses a vehicle fleet collision avoidance system and method based on fish streaming and belongs to the field of vehicle active safety. The system comprises an information acquisition module, a communication module, an information interaction module and a man-machine interaction module. The information acquisition module comprises a vehicle-mounted CAN bus, a millimeter wave radar distance measurement sensor and a longitudinal acceleration sensor which is used for acquiring the speed, the acceleration and the vehicle distance of a corresponding vehicle; the communication module comprises a vehicle-mounted unit OBU which is used for transferring motion state data among vehicles; the man-machine interaction module comprises a display unit and a voice prompt unit which is used for displaying dangerous information to a driver; the information processing module calculates acceleration information of vehicle collision avoidance according to the information transferred by the information acquisition module and the communication module through a kinematic model based on fish streaming, the information is provided to the driver through the man-machine interaction module, and collaborative collision avoidance of a vehicle fleet is achieved. By means of the vehicle fleet collision avoidance system and method, the active safety of vehicle fleet driving can be effectively improved.

The invention discloses a rear-end collision prevention system and method used for a vehicle and relates to the field of vehicle safety. The rear-end collision prevention system used for the vehicle comprises an information collection unit, a control unit and an execution unit. The information collection unit is used for collecting the surrounding information of the vehicle, and the surrounding information comprises the lane line information, the front vehicle information and the rear vehicle information. The control unit is used for receiving and processing the information and sending out an execution instruction when a rear dangerous incoming vehicle is judged. The execution unit is used for reminding a driver of the vehicle and a driver of the rear vehicle after receiving the execution instruction. On the premise of security permission, if the driver of the vehicle has no time to respond, the system spaces out the vehicle and the rear vehicle or enables the vehicle to change a lane to avoid rear-end collision of the rear vehicle. The invention further provides the corresponding method. According to the rear-end collision prevention system and method, through the control unit, the driver is timely reminded of paying attention to safe driving or the vehicle is automatically controlled to accelerate or change the lane, and rear-end collision of the rear vehicle is effectively avoided.

The invention discloses an automobile four-wheel active steering control system which comprises a driver preset steering detecting device, an actual steering detecting device and an electronic control unit, wherein the driver preset steering detecting device is used for detecting the preset steering state of the driver in real time; the actual steering detecting device is used for detecting the actual steering state of the automobile in real time; the electronic control unit is used for analyzing and comparing detected signals of the driver preset steering detecting device and the actual steering detecting device and correspondingly controlling a front wheel steering controller and a rear wheel steering controller; and the driver preset steering detecting device and the actual steering detecting device are both connected with the electronic control unit. The automobile four-wheel active steering control system has reasonable design, is easy and convenient to use and operate and can effectively improve the controllability problem of the four-wheel steering automobile during turning, thereby greatly improving the safety of the automobile during meeting, overtaking and curve running.

The invention provides a hydrogen safety control method and system for a hydrogen fuel cell bus. Under the situation that a vehicle control unit monitors that the bus does not have severe alarm information, a hydrogen system controller monitors that a hydrogen storage bottle is in a normal state and a fuel cell controller monitors that a fuel cell is in a normal state, operation of a hydrogen bottleneck electromagnetic valve is unlocked and is locked otherwise. According to the hydrogen safety control method and system for the hydrogen fuel cell bus, active safety of a fuel cell bus system isstrengthened while relative national standard requirements of the safety of a hydrogen system of the fuel cell bus are met.

The invention discloses a coordination control system of a four-wheel independent drive and independent steering electric automobile. The coordination control system comprises a global signal feedback module, an entire vehicle control module, a coordination control module and a motor control module which are connected in sequence, wherein the entire vehicle control module comprises an entire vehicle controller, and a battery management system, a vehicle-mounted lighting device and a refrigerating and heating device which are connected with the entire vehicle controller. Since the coordination controller is arranged, over-complex design of the entire vehicle controller can be avoided, and the real-time response speed and the operation reliability of the entire vehicle controller, the coordination controller and the motor controller are improved. The energy utilization efficiency and the driving comfort of the four-wheel independent drive and independent steering electric automobile are improved by the coordination controller, and the safety in running is improved. A more scientific modular control is realized, the modular production of the electric automobile is facilitated, and the technical innovation of an electric automobile controller manufacturer is promoted, so that the development of the entire electric automobile industry is promoted.

The invention discloses a fuel gas dual-fuel electrical control device with a fuel gas leakage alarm function. The fuel gas dual-fuel electrical control device comprises a fuel gas electrical control unit (ECU), a fuel gas leakage sensor, a solenoid valve, a fuel gas jet rail, a decompressor and a fuel gas state indication switch, wherein the fuel gas leakage sensor is arranged on a fuel gas supply pipeline; one end of the solenoid valve is externally connected with a gas storage tank, and the other end of the solenoid valve passes through the decompressor and is connected with the fuel gas jet rail; the fuel gas ECU is used for controlling the solenoid valve and the fuel gas leakage sensor to be switched on or off; the fuel gas leakage sensor is used for detecting the concentration of external combustible gas and sending detected information to the fuel gas ECU through an electrical signal; the fuel gas state indication switch is connected with the fuel gas ECU and controlled by the fuel gas ECU. A fuel gas leakage alarm device is integrated in a fuel gas control system; once the leakage of fuel gas is detected, the fuel gas control system can be used for performing emergency disposal in first time without manual intervention and automatically making a switch to a fuel oil mode, so that the active safety of a vehicle is improved.

The invention relates to the technical field of intelligent driving, and discloses a self-adaptive cruising method. The method comprises the steps that the driving state information of a vehicle and the information of the surrounding driving environment of the vehicle are collected in real time; the obtained real-time information is processed, and according to the processing result, a self-adaptive cruising system enters a corresponding self-adaptive cruising state; according to the current state of the self-adaptive cruising system, a target vehicle is determined, and the target vehicle is displayed on a vehicle-mounted display device. The invention further discloses the self-adaptive cruising system. The system comprises a real-time information collection module, a real-time data processing module and a target vehicle display module. By means of the self-adaptive cruising method and system, the display information of the target vehicle can be provided for a driver in different statesof the self-adaptive cruising system so that the driver can better know the surrounding driving environment and can know the current state of the system in real time, and it is convenient for the driver to better use the self-adaptive cruising function.

The invention belongs to the technical field of coal mine downhole railless auxiliary transportation equipment design and manufacturing and particularly provides a mining driving force self adoption multi-gear automatic speed changing double-motor steering drive axle. By adoption of the mining driving force self adoption multi-gear automatic speed changing double-motor steering drive axle, the problem that a mining electric drive vehicle cannot efficiently meet the demands of coal mine downhole complex and variable working conditions is solved. The steering drive axle comprises a water cooled middle double-drive anti-explosion motor, a first planetary reducing mechanism, a second planetary reducing mechanism, a differential mechanism, an axle shaft, an axle shell and an electronic control unit. The mining driving force self adoption multi-gear automatic speed changing double-motor steering drive axle simultaneously has the functions of driving, steering, automatic speed changing, active safety, travelling braking and parking braking, and mechanical control gear shifting devices, clutches, transmissions, transmission shafts, mechanical differential mechanisms and the like needed by traditional vehicles are omitted, so that a drive system and a whole vehicle are simple in structure and short in transmission chain, and transmission efficiency is improved.