Vehicle cooperative control method, device, equipment and medium

Abstract

The invention relates to the technical field of vehicle marshalling, discloses a vehicle cooperative control method, device and equipment and a medium, and aims to analyze the running state information of a coupled marshalling vehicle by using a virtual coupled safety protection model to determine an expected vehicle distance and a planned speed of a following vehicle. And determining a real spacing distance and a speed difference according to respective positions and speeds of the leading vehicle and the following vehicle. Constructing constraint conditions based on the expected vehicle distance, the following vehicle planning speed, the real spacing distance, the speed difference, the following vehicle acceleration and the following vehicle acceleration increment; and analyzing the real spacing distance and the speed difference at the current moment under the constraint condition to determine the expected acceleration of the following vehicle. And updating the speed and position of the following vehicle according to the expected acceleration of the following vehicle. The virtual coupling safety protection model is adopted for analysis, multiple targets such as the vehicle distance, the speed and the acceleration are restrained, the more scientific and reasonable expected acceleration of the following vehicle is obtained, and the passing efficiency of the vehicle is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle formation, and in particular to a vehicle cooperative control method, device, equipment and medium. Background Art

[0002] Vehicle convoy driving is a method of driving multiple vehicles at the same time on the road. It utilizes the coordination between vehicles so that the vehicles in the convoy can be arranged more closely together, thereby improving the traffic efficiency of the road.

[0003] The traditional marshaling driving method controls all vehicles to travel at the same speed while maintaining a fixed distance from the vehicle in front. The marshaling driving method requires the vehicles in the convoy to have real-time collaborative control capabilities. If the speed of the vehicles in the convoy deviates, the driving efficiency of the entire marshaling will be affected. In particular, when a vehicle in the marshaling breaks down or a vehicle control operation error occurs, it will threaten the safety of the entire marshaling and seriously affect the traffic efficiency of the vehicles.

[0004] It can be seen that how to improve the traffic efficiency of vehicles is a problem that technical personnel in this field need to solve. Summary of the invention

[0005] The purpose of the embodiments of the present invention is to provide a vehicle cooperative control method, device, equipment and medium, which can improve the traffic efficiency of vehicles.

[0006] In order to solve the above technical problems, an embodiment of the present invention provides a vehicle cooperative control method, including:

[0007] The virtual coupling safety protection model is used to analyze the running status information of the coupled vehicles to determine the expected vehicle spacing and the planned speed of the following vehicle; the running status information includes the position, speed and acceleration of the leading vehicle and the following vehicle respectively;

[0008] According to the positions and speeds of the lead vehicle and the following vehicle in the coupled train, the actual interval and speed difference between the lead vehicle and the following vehicle are determined;

[0009] Constructing constraint conditions based on the desired inter-vehicle distance, the planned speed of the following vehicle, the actual interval distance, the speed difference, the following vehicle acceleration, and the following vehicle acceleration increment;

[0010] Under the constraints, the actual interval distance and speed difference at the current moment are analyzed to determine the expected acceleration of the following vehicle;

[0011] The speed and position of the following vehicle are updated according to the expected acceleration of the following vehicle.

[0012] On the one hand, the virtual coupling safety protection model is used to analyze the running status information of the coupled vehicles to determine the expected vehicle spacing and the planned speed of the following vehicle, including:

[0013] According to the operating status information of the leading vehicle and the following vehicle, the discrete state space equations of the leading vehicle and the following vehicle at each time interval are constructed;

[0014] The calculation function of the virtual coupling safety protection model is used to process the safety speed limit, safety tracking distance, maximum traction acceleration, minimum braking acceleration, discrete time interval and upper limit of impact rate of the following vehicle to construct the following vehicle constraint conditions.

[0015] According to the principle of speed consistency between the leading vehicle and the following vehicle and minimization of the tracking distance, the objective function of the following vehicle is constructed;

[0016] According to the discrete state space equation, the following vehicle constraint conditions, and the initial positions, initial velocities, and initial accelerations of the lead vehicle and the following vehicle, the following vehicle objective function is analyzed to determine the expected vehicle spacing and the following vehicle planned velocity at each time interval.

[0017] On the one hand, according to the respective positions and speeds of the lead vehicle and the following vehicle in the coupled vehicle, the actual interval distance and speed difference between the lead vehicle and the following vehicle are determined, including:

[0018] Using the on-board wireless communication equipment to obtain the position and speed of the pilot vehicle and the position and speed of the following vehicle;

[0019] The position difference between the leading vehicle and the following vehicle is taken as the actual interval distance; the speed difference between the leading vehicle and the following vehicle is taken as the speed difference.

[0020] On the one hand, it also includes:

[0021] When the position and speed of the lead vehicle and the follower vehicle cannot be obtained using the on-board wireless communication equipment, the millimeter-wave radar is used for distance and speed perception to determine the actual interval distance and speed difference between the lead vehicle and the follower vehicle.

[0022] On the one hand, based on the desired inter-vehicle distance, the planned speed of the following vehicle, the actual interval distance, the speed difference, the following vehicle acceleration, and the following vehicle acceleration increment, constructing the constraint condition includes:

[0023] Determine the vehicle spacing error based on the actual spacing distance between the lead vehicle and the following vehicle and the corresponding expected vehicle spacing;

[0024] Constraints are determined based on the limit range of the inter-vehicle distance error, the limit range of the speed difference, the limit range of the following vehicle acceleration, the limit range of the following vehicle planned speed, and the limit range of the following vehicle acceleration increment.

[0025] On the one hand, analyzing the actual interval distance and speed difference at the current moment under the constraint conditions to determine the expected acceleration of the following vehicle includes:

[0026] According to the principles of minimum spacing error, minimum speed error, minimum vehicle acceleration, speed limit that meets the planned speed of the following vehicle, and minimum acceleration increment, the objective function is optimized to determine the expected acceleration of the following vehicle; wherein the formula corresponding to the objective function is as follows:

[0027] ;

[0028] Among them, e d represents the inter-vehicle distance error, e v represents the speed difference, a i represents the following vehicle acceleration, v f(i) represents the planned speed of the following vehicle, v ref represents the expected speed of the following vehicle, a des represents the expected acceleration of the following vehicle, represents the acceleration increment of the following vehicle, and w1, w2, w3, w4 and w5 all represent weight coefficients.

[0029] On the one hand, after updating the speed and position of the following vehicle according to the expected acceleration of the following vehicle, the method further includes:

[0030] The updated speed and position are transmitted to other vehicles in the coupled vehicle train.

[0031] The embodiment of the present invention further provides a vehicle cooperative control device, comprising a first determination unit, a second determination unit, a construction unit, an analysis unit, and an update unit;

[0032] The first determination unit is used to analyze the running status information of the coupled vehicles using the virtual coupled safety protection model to determine the expected vehicle spacing and the planned speed of the following vehicle; wherein the running status information includes the position, speed and acceleration of the lead vehicle and the following vehicle respectively;

[0033] The second determination unit is used to determine the actual interval distance and speed difference between the leading vehicle and the following vehicle according to the respective positions and speeds of the leading vehicle and the following vehicle in the coupled vehicle train;

[0034] The construction unit is used to construct a constraint condition based on the desired vehicle spacing, the planned speed of the following vehicle, the actual spacing distance, the speed difference, the following vehicle acceleration, and the following vehicle acceleration increment;

[0035] The analysis unit is used to analyze the actual interval distance and speed difference at the current moment under the constraint condition to determine the expected acceleration of the following vehicle;

[0036] The updating unit is used to update the speed and position of the following vehicle according to the expected acceleration of the following vehicle.

[0037] On the one hand, the first determination unit is used to construct discrete state space equations of the lead vehicle and the follower vehicle at each time interval according to their respective operating status information; use the calculation function of the virtual coupling safety protection model to process the safe speed limit, safe tracking distance, maximum traction acceleration, minimum braking acceleration, discrete time interval and impact rate upper limit of the follower vehicle to construct the follower vehicle constraint conditions; construct the follower vehicle objective function according to the principles of speed consistency and tracking distance minimization between the lead vehicle and the follower vehicle; analyze the follower vehicle objective function according to the discrete state space equations, the follower vehicle constraint conditions and the initial positions, initial speeds and initial accelerations of the lead vehicle and the follower vehicle to determine the expected vehicle spacing and the follower vehicle planned speed at each time interval.

[0038] In one aspect, the second determining unit includes an acquiring subunit and an acting subunit;

[0039] The acquisition subunit is used to acquire the position and speed of the pilot vehicle and the position and speed of the following vehicle using the vehicle-mounted wireless communication device;

[0040] The subunit is used to take the position difference between the leading vehicle and the following vehicle as the real interval distance; and take the speed difference between the leading vehicle and the following vehicle as the speed difference.

[0041] On the one hand, it also includes the perception unit;

[0042] The sensing unit is used to sense the distance and speed using the millimeter wave radar when the position and speed of the lead vehicle and the position and speed of the follower vehicle cannot be obtained using the vehicle-mounted wireless communication equipment, so as to determine the actual interval distance and speed difference between the lead vehicle and the follower vehicle.

[0043] On the one hand, the construction unit is used to determine the vehicle spacing error based on the actual interval distance between the lead vehicle and the following vehicle and the corresponding expected vehicle spacing; and determine the constraint conditions based on the limit range of the vehicle spacing error, the limit range of the speed difference, the limit range of the following vehicle acceleration, the limit range of the following vehicle planned speed and the limit range of the following vehicle acceleration increment.

[0044] On the one hand, the analysis unit is used to optimize the objective function according to the principles of minimum spacing error, minimum vehicle speed error, minimum vehicle acceleration, speed limit that meets the planned speed of the following vehicle, and minimum acceleration increment to determine the expected acceleration of the following vehicle; wherein the formula corresponding to the objective function is as follows:

[0045] ;

[0046] Among them, e d represents the inter-vehicle distance error, e v represents the speed difference, a i represents the following vehicle acceleration, v f(i) represents the planned speed of the following vehicle, v ref represents the expected speed of the following vehicle, a des represents the expected acceleration of the following vehicle, represents the acceleration increment of the following vehicle, and w1, w2, w3, w4 and w5 all represent weight coefficients.

[0047] On the one hand, it also includes a transmission unit;

[0048] The transmission unit is used to transmit the updated speed and position to other vehicles in the coupled vehicle group.

[0049] The embodiment of the present invention further provides a vehicle cooperative control device, including:

[0050] Memory for storing computer programs;

[0051] A processor is used to execute the computer program to implement the steps of the vehicle cooperative control method as described above.

[0052] An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the vehicle cooperative control method as described above are implemented.

[0053] It can be seen from the above technical scheme that the virtual coupling safety protection model is used to analyze the running status information of the coupled vehicles to determine the expected vehicle spacing and the planned speed of the following vehicle; wherein the running status information includes the position, speed and acceleration of the lead vehicle and the following vehicle. According to the position and speed of the lead vehicle and the following vehicle in the coupled vehicles, the actual spacing distance and speed difference between the lead vehicle and the following vehicle are determined. In order to improve the road traffic flow, a multi-objective and multi-constraint calculation method can be considered. Therefore, the constraint conditions can be constructed based on the expected vehicle spacing, the planned speed of the following vehicle, the actual spacing distance, the speed difference, the following vehicle acceleration and the following vehicle acceleration increment; under the constraint conditions, the actual spacing distance and speed difference at the current moment are analyzed to determine the expected acceleration of the following vehicle. According to the expected acceleration of the following vehicle, the speed and position of the following vehicle are updated. In this technical scheme, the virtual coupling safety protection model can be used to fully analyze the position, speed and acceleration of the vehicle, so as to calculate a closer, safer and more reasonable expected vehicle spacing and planned speed of the following vehicle. By constraining the vehicle spacing, speed and acceleration at the same time, a more scientific and reasonable expected acceleration of the following vehicle can be obtained. According to the expected acceleration of the following vehicle, the speed and position of the following vehicle can be reasonably controlled to ensure the coordination between the following vehicle and the leading vehicle, so that the coupled vehicles can be arranged together more compactly and the traffic efficiency of the vehicles can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0055] Figure 1 A flow chart of a vehicle cooperative control method provided by an embodiment of the present invention;

[0056] Figure 2 A schematic diagram of cooperative driving of vehicles provided by an embodiment of the present invention;

[0057] Figure 3 A flow chart of a method for determining an expected vehicle spacing and a planned speed of a following vehicle provided by an embodiment of the present invention;

[0058] Figure 4 A schematic diagram of the structure of a vehicle cooperative control device provided by an embodiment of the present invention;

[0059] Figure 5 A structural diagram of a vehicle cooperative control device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0060] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0061] The terms "including" and "having" in the specification of the present invention and the above-mentioned drawings, as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but may include steps or units that are not listed.

[0062] In order to enable those skilled in the art to better understand the solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0063] Next, a vehicle cooperative control method provided by an embodiment of the present invention is introduced in detail. Figure 1 A flow chart of a vehicle cooperative control method provided by an embodiment of the present invention, the method comprising:

[0064] S101: Analyze the running status information of the coupled vehicles using the virtual coupled safety protection model to determine the expected vehicle spacing and the planned speed of the following vehicle.

[0065] The running status information may include the position, speed and acceleration of the lead vehicle and the follower vehicle respectively.

[0066] The vehicle cooperative control method provided in the embodiment of the present invention can be applied to the cooperative control of trains in the virtual coupling mode. In order to calculate a closer, safer and more reasonable vehicle spacing and improve road traffic flow, a virtual coupling safety protection model can be used to analyze the running status information of the coupled vehicles.

[0067] In practical applications, a single-particle model can be used to describe the motion process of coupled vehicles, thereby constructing the corresponding discrete state space equations. In order to ensure the safety of driving speed, following distance, traction / braking characteristics of the following vehicle, and riding comfort, the following vehicle constraint conditions can be constructed. The following vehicle objective function is constructed by comprehensively considering the consistency of the front and rear vehicle speeds and the minimization of the front and rear vehicle tracking distance. The objective function is solved under the discrete state space equations and constraints to determine the desired vehicle distance and the following vehicle planning speed.

[0068] S102: Determine the actual interval distance and speed difference between the leading vehicle and the following vehicle according to the respective positions and speeds of the leading vehicle and the following vehicle in the coupled vehicle train.

[0069] The coupled train set may include multiple vehicles. In the embodiment of the present invention, the vehicle located at the front of the coupled train set may be called a lead vehicle, and any vehicle located behind the lead vehicle may be called a following vehicle.

[0070] Each vehicle may be provided with an on-board wireless communication device, which may be a communication module based on an LTE network. Real-time communication may be achieved between vehicles through the on-board wireless communication device.

[0071] In an embodiment of the present invention, the position and speed of the lead vehicle and the position and speed of the following vehicle can be obtained by using the vehicle-mounted wireless communication device; the position difference between the lead vehicle and the following vehicle is used as the actual interval distance; and the speed difference between the lead vehicle and the following vehicle is used as the speed difference.

[0072] In order to prevent the failure of distance estimation due to communication interruption, when the position and speed of the lead vehicle and the follower vehicle cannot be obtained using the on-board wireless communication equipment, millimeter-wave radar can be used for distance and speed perception to determine the actual interval distance and speed difference between the lead vehicle and the follower vehicle.

[0073] S103: Constructing constraint conditions based on the expected vehicle spacing, the planned speed of the following vehicle, the actual spacing distance, the speed difference, the following vehicle acceleration, and the following vehicle acceleration increment.

[0074] In the embodiment of the present invention, a model predictive controller (MPC) can be used to calculate the control quantity and send it to the chassis of the following vehicle for vehicle control. In order to calculate a more scientific, reasonable and comfortable speed curve for the following vehicle, multiple objectives and multiple constraints can be considered. The multiple objectives can include vehicle spacing, vehicle speed error, vehicle acceleration, vehicle speed limit and acceleration increment. Multiple constraints can include maintaining the minimum spacing error, the minimum speed error, the minimum vehicle acceleration, the speed limit condition that meets the speed of the following vehicle, the minimum acceleration increment, etc.

[0075] In practical applications, the vehicle spacing error can be determined based on the actual interval distance between the leading vehicle and the following vehicle and the corresponding expected vehicle spacing; the constraint conditions can be determined based on the limit range of the vehicle spacing error, the limit range of the speed difference, the limit range of the following vehicle acceleration, the limit range of the following vehicle planned speed, and the limit range of the following vehicle acceleration increment.

[0076] Figure 2 A schematic diagram of a vehicle cooperative driving provided by an embodiment of the present invention, Figure 2In the example of three vehicles, for the sake of convenience, the three vehicles can be called vehicle 1, vehicle 2 and vehicle 3 in order from left to right. Vehicle 1 on the far left can be used as the leading vehicle, and vehicles 2 and 3 behind it are both following vehicles. The speed of vehicle 1 is v i-1 , the acceleration is a i-1 ; The speed of vehicle 2 is v i , the acceleration is a i ; The speed of vehicle 3 is v i+1 , the acceleration is a i+1 .d des represents the expected vehicle spacing, e d Indicates the vehicle spacing error.

[0077] For the following vehicle, a single-mass model is used to describe the motion of the vehicle. Its triple integral kinematic state equation based on displacement, velocity, and acceleration is as follows:

[0078] ;

[0079] Among them, e d Indicates the inter-vehicle distance error, e v represents the speed difference, d des represents the expected vehicle spacing, a des represents the expected acceleration of the following vehicle, v i represents the speed of the following vehicle, represents the differential value of the inter-vehicle distance error, represents the differential value of the expected vehicle spacing, represents the differential value of the speed difference, represents the differential value of the following vehicle’s acceleration, It represents the differential value of the speed of the following vehicle, and τ represents the braking and traction properties of the vehicle. τ can be set to about 0.7s.

[0080] Inter-vehicle distance error d =d actual -d des , d actual Indicates the actual separation distance, d des Indicates the expected vehicle spacing. The actual spacing distance can be obtained by locating the coordinates of the two vehicles and then accumulating the nearest points on the tracking path, or by sensing with millimeter-wave radar.

[0081] Speed ​​difference v = v i-1 -v i , v i-1 Indicates the real speed of the pilot vehicle, which can be transmitted to the following vehicle through the on-board wireless communication device, v i Indicates the true speed of the following vehicle.

[0082] In the embodiment of the present invention, in order to ensure that the actual interval distance is close to the expected vehicle interval, the speed of the leading vehicle and the following vehicle are close, the acceleration of the following vehicle is as small as possible to ensure comfort and economy, the following vehicle can track the expected speed curve under planning, and the following vehicle adjusts traction and braking as little as possible to improve smoothness and economy, constraint limits can be set for the vehicle interval error, speed difference, following vehicle acceleration, following vehicle actual speed, and minimum acceleration increment, respectively. The constructed constraint conditions are as follows:

[0083] ;

[0084] in, represents the acceleration increment of the following vehicle, l bx1 , l bx2 , l bx3 , l bx4 , l bu are the lower limits corresponding to different parameters, u bx1 、u bx2 、u bx3 、u bx4 、u bu are the upper limits corresponding to different parameters respectively.

[0085] u bx4 The vehicle EBI speed calculation function can be used to analyze the planned speed of the following vehicle. bx4 In addition, other lower and upper limits can be pre-set.

[0086] In the above constraints, e d The constraint describes how to keep the inter-vehicle distance error within a small range. v The constraint describes that the speed of the following car and the leading car should be as close as possible. i The constraint describes that the acceleration of the following vehicle should be kept within a safe and comfortable range, v i The constraint describes that the speed of the following vehicle must meet the set road speed limit. The constraint describes that the acceleration increment of the following vehicle needs to be kept within a small range to ensure smooth and economical driving.

[0087] S104: Analyze the actual interval distance and speed difference at the current moment under the constraint condition to determine the expected acceleration of the following vehicle.

[0088] In the embodiment of the present invention, the objective function can be optimized according to the principles of minimum spacing error, minimum vehicle speed error, minimum vehicle acceleration, speed limit that satisfies the planned speed of the following vehicle, and minimum acceleration increment to determine the expected acceleration of the following vehicle; wherein the formula corresponding to the objective function is as follows:

[0089] ;

[0090] Among them, e d Indicates the inter-vehicle distance error, e v represents the speed difference, a i represents the acceleration of the following vehicle, v f(i) represents the planned speed of the following vehicle, v ref represents the expected speed of the following vehicle, a des represents the expected acceleration of the following vehicle, represents the acceleration increment of the following vehicle, w1, w2, w3, w4 and w5 all represent weight coefficients. The value of the weight coefficient can be reasonably adjusted according to the actual situation.

[0091] By minimizing the sum of each weight, the values ​​of each parameter can be solved. In the embodiment of the present invention, the speed and position of the following vehicle are adjusted mainly by using the solved expected acceleration of the following vehicle to ensure the smoothness of the following vehicle speed and the consistency with the speed of the leading vehicle as much as possible.

[0092] S105: updating the speed and position of the following vehicle according to the expected acceleration of the following vehicle.

[0093] At each discrete moment, the following vehicle has its corresponding speed and position. According to the expected acceleration of the following vehicle at the current moment, the speed and position of the following vehicle at the next moment can be calculated.

[0094] In order to ensure the real-time communication between vehicles, after the speed and position of the following vehicle are updated according to the expected acceleration of the following vehicle, the updated speed and position can be transmitted to other vehicles in the coupled train.

[0095] It can be seen from the above technical scheme that the virtual coupling safety protection model is used to analyze the running status information of the coupled vehicles to determine the expected vehicle spacing and the planned speed of the following vehicle; wherein the running status information includes the position, speed and acceleration of the lead vehicle and the following vehicle. According to the position and speed of the lead vehicle and the following vehicle in the coupled vehicles, the actual spacing distance and speed difference between the lead vehicle and the following vehicle are determined. In order to improve the road traffic flow, a multi-objective and multi-constraint calculation method can be considered. Therefore, the constraint conditions can be constructed based on the expected vehicle spacing, the planned speed of the following vehicle, the actual spacing distance, the speed difference, the following vehicle acceleration and the following vehicle acceleration increment; under the constraint conditions, the actual spacing distance and speed difference at the current moment are analyzed to determine the expected acceleration of the following vehicle. According to the expected acceleration of the following vehicle, the speed and position of the following vehicle are updated. In this technical scheme, the virtual coupling safety protection model can be used to fully analyze the position, speed and acceleration of the vehicle, so as to calculate a closer, safer and more reasonable expected vehicle spacing and planned speed of the following vehicle. By constraining the vehicle spacing, speed and acceleration at the same time, a more scientific and reasonable expected acceleration of the following vehicle can be obtained. According to the expected acceleration of the following vehicle, the speed and position of the following vehicle can be reasonably controlled to ensure the coordination between the following vehicle and the leading vehicle, so that the coupled vehicles can be arranged together more compactly and the traffic efficiency of the vehicles can be improved.

[0096] Figure 3 A flowchart of a method for determining an expected vehicle spacing and a planned speed of a following vehicle provided by an embodiment of the present invention, the method comprising:

[0097] S301: constructing discrete state space equations of the leading vehicle and the following vehicle at each time interval according to the respective operating state information of the leading vehicle and the following vehicle.

[0098] The running status information may include speed, acceleration, position and other information.

[0099] In the embodiment of the present invention, a single-particle model can be used to describe the motion process of the pilot vehicle and the follower vehicle, and the corresponding discrete state space equation is as follows:

[0100] ;

[0101] in, is a discrete time interval, is the position of the pilot vehicle at the i-th time interval, is the speed of the pilot car at the i-th time interval, is the acceleration of the pilot car at the i-th time interval, is the position of the pilot car at the i+1th time interval, is the speed of the pilot car at the i+1th time interval, is the position of the following vehicle at the i-th time interval, is the speed of the following vehicle at the i-th time interval, is the acceleration of the following vehicle at the i-th time interval, is the position of the following vehicle at the i+1th time interval, is the speed of the following vehicle at the i+1th time interval, is the planned tracking distance of the following vehicle relative to the leading vehicle at the i-th time interval.

[0102] S302: Using the calculation function of the virtual coupling safety protection model, the safe speed limit, safe tracking distance, maximum traction acceleration, minimum braking acceleration, discrete time interval and impact rate upper limit of the following vehicle are processed to construct the following vehicle constraint conditions.

[0103] From the perspective of the following vehicle, only the initial state of the coupling formation is needed, which is usually obtained through sensors. The initial states of the leading vehicle and the following vehicle are as follows:

[0104] , , , , , , ,

[0105] in, , , are the initial position, velocity and acceleration of the pilot car respectively; , , are the initial position, velocity and acceleration of the following vehicle, is the initial tracking distance of the following vehicle to the leading vehicle.

[0106] In the embodiment of the present invention, in order to ensure the driving speed safety, the speed of the following vehicle cannot exceed the safety speed limit during the operation, so the safety speed limit constraint condition of the following vehicle is:

[0107] ;

[0108] Among them, f EBI1 represents the first type EBI speed calculation function of the vehicle, which can be provided by the virtual coupling safety protection model; v lim represents the safety margin of the road section, v lim >0; Indicates the target stopping distance of the following vehicle.

[0109] To ensure the following distance is safe, the tracking distance during the following vehicle operation cannot exceed the safe tracking distance. The safe tracking distance constraints are as follows:

[0110] ;

[0111] Among them, f SHW It represents the calculation function of the minimum safe tracking distance of the following vehicle, which can be provided by the virtual coupling safety protection model; Indicates the safe tracking distance.

[0112] The safety speed limit constraint of the following vehicle combined with the safety tracking distance constraint ensures the vehicle's second-category EBI speed constraint, which can be understood as splitting the vehicle's second-category EBI speed constraint into the vehicle's first-category EBI speed constraint and the safety tracking distance constraint, which is convenient for iterative optimization calculation.

[0113] The traction / braking characteristics of the following vehicle determine the maximum traction / minimum braking acceleration that the vehicle can exert, so the constraints corresponding to the acceleration are as follows:

[0114] ;

[0115] in, Indicates the minimum braking acceleration of the following vehicle. ; Indicates the maximum traction acceleration of the following vehicle, .

[0116] To ensure riding comfort, the impact rate of the following vehicle during operation must not exceed its upper limit. The corresponding constraints are as follows:

[0117] ;

[0118] Among them, j max Indicates the upper limit of the impact rate, 0 <j max .

[0119] S303: Constructing a follower vehicle objective function according to the principle of speed consistency between the lead vehicle and the follower vehicle and minimizing the tracking distance.

[0120] In the embodiment of the present invention, the consistency of the speeds of the front and rear vehicles and the minimization of the tracking distance between the front and rear vehicles can be comprehensively considered to plan the objective function of the following vehicle; wherein the front and rear vehicles include the leading vehicle and the following vehicle, and the objective function of the following vehicle is as follows:

[0121] ;

[0122] Among them, w v represents the optimization weight of the speed difference between the leading vehicle and the following vehicle, w d Represents the optimization weight of the tracking distance between the leader vehicle and the following vehicle.

[0123] S304: Analyze the objective function of the following vehicle according to the discrete state space equation, the following vehicle constraint conditions, and the initial positions, initial velocities, and initial accelerations of the lead vehicle and the following vehicle, so as to determine the expected vehicle spacing and the planned velocity of the following vehicle at each time interval.

[0124] The objective function of the following vehicle and all its corresponding constraints are as follows:

[0125] ;

[0126] st:

[0127] ;

[0128] , , , , , , ;

[0129] ;

[0130] ;

[0131] ;

[0132] .

[0133] Using the quadratic programming solver, the above optimization problem can be solved to obtain T0 to Each discrete moment corresponds to , , , , thus obtaining the following vehicle planning speed curve and the expected vehicle spacing curve.

[0134] In the embodiment of the present invention, the speed of the following vehicle is planned according to all time intervals. , the planned speed curve of the following vehicle can be obtained.

[0135] In the embodiment of the present invention, the formula for the desired vehicle spacing is as follows:

[0136] ;

[0137] in, , represents the expected inter-vehicle distance of the following vehicle in the i-th time interval. The expected inter-vehicle distance of the following vehicle is also the minimum safe tracking distance of the following vehicle, f SHWIt represents the calculation function of the minimum safe tracking distance of the following vehicle. According to the expected vehicle distance under all time intervals, the expected vehicle distance curve of the following vehicle can be obtained.

[0138] After obtaining the planned speed of the following vehicle, the vehicle EBI speed calculation function can be used to analyze the planned speed of the following vehicle to obtain the speed limit of the following vehicle. The formula for the speed limit of the following vehicle is as follows:

[0139] ;

[0140] in, It represents the second type EBI speed calculation function of the vehicle, which can be provided by the virtual coupling safety protection model; represents the speed limit of the following vehicle in the i-th time interval, i.e., the EBI speed. Based on the speed limit of the following vehicle in all time intervals, the corresponding EBI speed curve can be obtained. In practical applications, when constructing the constraint conditions of the objective function, the EBI speed can be used as u bx4 .

[0141] In addition to using an MPC controller that considers multiple factors to perform calculation tasks, the present invention can also use simple PID, LQR controllers, etc. to control vehicle spacing and vehicle speed. The PID controller can perform closed-loop control on vehicle spacing and vehicle speed difference, respectively, to form a multi-loop feedback control. The LQR controller uses an offline control rate, inputs the desired spacing, and calculates the control amount through the control rate for feedforward control.

[0142] Figure 4 A schematic diagram of the structure of a vehicle cooperative control device provided by an embodiment of the present invention includes a first determination unit 41, a second determination unit 42, a construction unit 43, an analysis unit 44 and an update unit 45;

[0143] The first determination unit 41 is used to analyze the running status information of the coupled vehicles by using the virtual coupled safety protection model to determine the expected vehicle spacing and the planned speed of the following vehicle; wherein the running status information includes the position, speed and acceleration of the leading vehicle and the following vehicle respectively;

[0144] The second determining unit 42 is used to determine the actual interval distance and speed difference between the leading vehicle and the following vehicle according to the respective positions and speeds of the leading vehicle and the following vehicle in the coupled vehicle train;

[0145] A construction unit 43, configured to construct a constraint condition based on a desired vehicle spacing, a planned speed of a following vehicle, an actual spacing distance, a speed difference, an acceleration of a following vehicle, and an acceleration increment of a following vehicle;

[0146] An analysis unit 44 is used to analyze the actual interval distance and speed difference at the current moment under the constraint condition to determine the expected acceleration of the following vehicle;

[0147] The updating unit 45 is used to update the speed and position of the following vehicle according to the expected acceleration of the following vehicle.

[0148] In some embodiments, the first determination unit is used to construct discrete state space equations of the lead vehicle and the follower vehicle at each time interval based on the respective operating status information of the lead vehicle and the follower vehicle; use the calculation function of the virtual coupling safety protection model to process the safe speed limit, safe tracking distance, maximum traction acceleration, minimum braking acceleration, discrete time interval and impact rate upper limit of the follower vehicle to construct the follower vehicle constraint conditions; construct the follower vehicle objective function according to the principles of speed consistency and tracking distance minimization between the lead vehicle and the follower vehicle; analyze the follower vehicle objective function based on the discrete state space equations, the follower vehicle constraint conditions, and the initial positions, initial speeds and initial accelerations of the lead vehicle and the follower vehicle to determine the expected vehicle spacing and the planned speed of the follower vehicle at each time interval.

[0149] In some embodiments, the second determining unit includes an acquiring subunit and an acting subunit;

[0150] An acquisition subunit, used to acquire the position and speed of the pilot vehicle and the position and speed of the following vehicle using the vehicle-mounted wireless communication device;

[0151] As a subunit, it is used to take the position difference between the leading vehicle and the following vehicle as the real interval distance; and take the speed difference between the leading vehicle and the following vehicle as the speed difference.

[0152] In some embodiments, a sensing unit is also included;

[0153] The sensing unit is used to sense the distance and speed using the millimeter wave radar when the position and speed of the lead vehicle and the position and speed of the follower vehicle cannot be obtained using the vehicle-mounted wireless communication equipment, so as to determine the actual interval distance and speed difference between the lead vehicle and the follower vehicle.

[0154] In some embodiments, the construction unit is used to determine the vehicle spacing error based on the actual spacing distance between the lead vehicle and the following vehicle and the corresponding expected vehicle spacing; and determine the constraint conditions based on the limit range of the vehicle spacing error, the limit range of the speed difference, the limit range of the following vehicle acceleration, the limit range of the following vehicle planned speed, and the limit range of the following vehicle acceleration increment.

[0155] In some embodiments, the analysis unit is used to optimize the objective function according to the principle of minimum spacing error, minimum vehicle speed error, minimum vehicle acceleration, speed limit that meets the planned speed of the following vehicle, and minimum acceleration increment to determine the expected acceleration of the following vehicle; wherein the formula corresponding to the objective function is as follows:

[0156] ;

[0157] Among them, e d Indicates the inter-vehicle distance error, e v represents the speed difference, a i represents the acceleration of the following vehicle, v f(i) represents the planned speed of the following vehicle, v ref represents the expected speed of the following vehicle, a des represents the expected acceleration of the following vehicle, represents the acceleration increment of the following vehicle, and w1, w2, w3, w4 and w5 all represent weight coefficients.

[0158] In some embodiments, a delivery unit is also included;

[0159] The transmission unit is used to transmit the updated speed and position to other vehicles in the coupled vehicle group.

[0160] Figure 4 The description of the features in the corresponding embodiments can be found in Figure 1 The relevant descriptions of the corresponding embodiments will not be repeated here one by one.

[0161] It can be seen from the above technical scheme that the virtual coupling safety protection model is used to analyze the running status information of the coupled vehicles to determine the expected vehicle spacing and the planned speed of the following vehicle; wherein the running status information includes the position, speed and acceleration of the lead vehicle and the following vehicle. According to the position and speed of the lead vehicle and the following vehicle in the coupled vehicles, the actual spacing distance and speed difference between the lead vehicle and the following vehicle are determined. In order to improve the road traffic flow, a multi-objective and multi-constraint calculation method can be considered. Therefore, the constraint conditions can be constructed based on the expected vehicle spacing, the planned speed of the following vehicle, the actual spacing distance, the speed difference, the following vehicle acceleration and the following vehicle acceleration increment; under the constraint conditions, the actual spacing distance and speed difference at the current moment are analyzed to determine the expected acceleration of the following vehicle. According to the expected acceleration of the following vehicle, the speed and position of the following vehicle are updated. In this technical scheme, the virtual coupling safety protection model can be used to fully analyze the position, speed and acceleration of the vehicle, so as to calculate a closer, safer and more reasonable expected vehicle spacing and planned speed of the following vehicle. By constraining the vehicle spacing, speed and acceleration at the same time, a more scientific and reasonable expected acceleration of the following vehicle can be obtained. According to the expected acceleration of the following vehicle, the speed and position of the following vehicle can be reasonably controlled to ensure the coordination between the following vehicle and the leading vehicle, so that the coupled vehicles can be arranged together more compactly and the traffic efficiency of the vehicles can be improved.

[0162] Figure 5 A structural diagram of a vehicle cooperative control device provided by an embodiment of the present invention, such as Figure 5As shown, the vehicle cooperative control device includes: a memory 50 for storing a computer program;

[0163] The processor 51 is used to implement the steps of the vehicle cooperative control method in the above embodiment when executing the computer program.

[0164] The vehicle cooperative control device provided in this embodiment may include but is not limited to a smart phone, a tablet computer, a laptop computer or a desktop computer.

[0165] Among them, the processor 51 may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor 51 may be implemented in at least one hardware form of digital signal processing (DSP), field-programmable gate array (FPGA), and programmable logic array (PLA). The processor 51 may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a central processing unit (CPU); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor 51 may be integrated with a graphics processing unit (GPU), and the GPU is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 51 may also include an artificial intelligence (AI) processor, which is used to process computing operations related to machine learning.

[0166] The memory 50 may include one or more computer-readable storage media, which may be non-transitory. The memory 50 may also include a high-speed random access memory, and a non-volatile memory, such as one or more disk storage devices, flash memory storage devices. In this embodiment, the memory 50 is at least used to store the following computer program 501, wherein, after the computer program is loaded and executed by the processor 51, it can implement the relevant steps of the vehicle cooperative control method disclosed in any of the aforementioned embodiments. In addition, the resources stored in the memory 50 may also include an operating system 502 and data 503, etc., and the storage method may be temporary storage or permanent storage. Among them, the operating system 502 may include Windows, Unix, Linux, etc. The data 503 may include but is not limited to the operating status information of the coupled vehicle, the actual interval distance and speed difference between the lead vehicle and the following vehicle, the expected acceleration of the following vehicle, etc.

[0167] In some embodiments, the vehicle cooperative control device may also include a display screen 52 , an input / output interface 53 , a communication interface 54 , a power supply 55 , and a communication bus 56 .

[0168] Those skilled in the art will understand that Figure 5 The structure shown in does not constitute a limitation of the vehicle cooperative control device and may include more or fewer components than shown in the figure.

[0169] It is understandable that if the vehicle cooperative control method in the above embodiment is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or part of the contribution to the current technology or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium and executes all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), electrically erasable programmable ROM, register, hard disk, removable disk, CD-ROM, magnetic disk or optical disk and other media that can store program code.

[0170] Based on this, an embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the vehicle cooperative control method as described above are implemented.

[0171] The above is a detailed introduction to a vehicle cooperative control method, device, equipment and computer-readable storage medium provided in an embodiment of the present invention. The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referenced to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description.

[0172] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0173] The above is a detailed introduction to a vehicle cooperative control method, device, equipment and computer-readable storage medium provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A vehicle cooperative control method, characterized in that: include: The virtual coupling safety protection model is used to analyze the running status information of the coupled vehicles to determine the expected vehicle spacing and the planned speed of the following vehicle; the running status information includes the position, speed and acceleration of the leading vehicle and the following vehicle respectively; According to the positions and speeds of the lead vehicle and the following vehicle in the coupled train, the actual interval and speed difference between the lead vehicle and the following vehicle are determined; Constructing constraint conditions based on the desired inter-vehicle distance, the planned speed of the following vehicle, the actual interval distance, the speed difference, the following vehicle acceleration, and the following vehicle acceleration increment; Under the constraints, the actual interval distance and speed difference at the current moment are analyzed to determine the expected acceleration of the following vehicle; The speed and position of the following vehicle are updated according to the expected acceleration of the following vehicle.

2. The vehicle cooperative control method according to claim 1, characterized in that: The virtual coupling safety protection model is used to analyze the running status information of the coupled vehicles to determine the expected vehicle spacing and the planned speed of the following vehicle, including: According to the operating status information of the leading vehicle and the following vehicle, the discrete state space equations of the leading vehicle and the following vehicle at each time interval are constructed; The calculation function of the virtual coupling safety protection model is used to process the safety speed limit, safety tracking distance, maximum traction acceleration, minimum braking acceleration, discrete time interval and upper limit of impact rate of the following vehicle to construct the following vehicle constraint conditions. According to the principle of speed consistency between the leading vehicle and the following vehicle and minimization of the tracking distance, the objective function of the following vehicle is constructed; According to the discrete state space equation, the following vehicle constraint conditions, and the initial positions, initial velocities, and initial accelerations of the lead vehicle and the following vehicle, the following vehicle objective function is analyzed to determine the expected vehicle spacing and the following vehicle planned velocity at each time interval.

3. The vehicle cooperative control method according to claim 1, characterized in that: According to the positions and speeds of the lead vehicle and the following vehicle in the coupled train, the actual interval distance and speed difference between the lead vehicle and the following vehicle are determined as follows: Using the on-board wireless communication equipment to obtain the position and speed of the pilot vehicle and the position and speed of the following vehicle; The position difference between the leading vehicle and the following vehicle is taken as the actual interval distance; the speed difference between the leading vehicle and the following vehicle is taken as the speed difference.

4. The vehicle cooperative control method according to claim 3, characterized in that: Also includes: When the position and speed of the lead vehicle and the follower vehicle cannot be obtained using the on-board wireless communication equipment, the millimeter-wave radar is used for distance and speed perception to determine the actual interval distance and speed difference between the lead vehicle and the follower vehicle.

5. The vehicle cooperative control method according to claim 1, characterized in that: Based on the desired vehicle spacing, the planned speed of the following vehicle, the actual spacing distance, the speed difference, the following vehicle acceleration, and the following vehicle acceleration increment, the constraint conditions are constructed including: Determine the vehicle spacing error based on the actual spacing distance between the lead vehicle and the following vehicle and the corresponding expected vehicle spacing; Constraints are determined based on the limit range of the inter-vehicle distance error, the limit range of the speed difference, the limit range of the following vehicle acceleration, the limit range of the following vehicle planned speed, and the limit range of the following vehicle acceleration increment.

6. The vehicle cooperative control method according to claim 5, characterized in that: Under the constraints, the actual interval distance and speed difference at the current moment are analyzed to determine the expected acceleration of the following vehicle, including: According to the principles of minimum spacing error, minimum speed error, minimum vehicle acceleration, speed limit that meets the planned speed of the following vehicle, and minimum acceleration increment, the objective function is optimized to determine the expected acceleration of the following vehicle; wherein the formula corresponding to the objective function is as follows: ； in, e d represents the inter-vehicle distance error, e v represents the speed difference, a i represents the following vehicle acceleration, v f(i) represents the planned speed of the following vehicle, v ref represents the expected speed of the following vehicle, a des represents the expected acceleration of the following vehicle, represents the acceleration increment of the following vehicle, w 1. w 2. w 3. w 4 and w 5 represents the weight coefficient.

7. The vehicle cooperative control method according to claim 1, characterized in that: After updating the speed and position of the following vehicle according to the expected acceleration of the following vehicle, the method further includes: The updated speed and position are transmitted to other vehicles in the coupled vehicle train.

8. A vehicle cooperative control device, characterized in that: comprising a first determining unit, a second determining unit, a constructing unit, an analyzing unit and an updating unit; The first determination unit is used to analyze the running status information of the coupled vehicles using the virtual coupled safety protection model to determine the expected vehicle spacing and the planned speed of the following vehicle; wherein the running status information includes the position, speed and acceleration of the lead vehicle and the following vehicle respectively; The second determination unit is used to determine the actual interval distance and speed difference between the leading vehicle and the following vehicle according to the respective positions and speeds of the leading vehicle and the following vehicle in the coupled vehicle train; The construction unit is used to construct a constraint condition based on the desired vehicle spacing, the planned speed of the following vehicle, the actual spacing distance, the speed difference, the following vehicle acceleration, and the following vehicle acceleration increment; The analysis unit is used to analyze the actual interval distance and speed difference at the current moment under the constraint condition to determine the expected acceleration of the following vehicle; The updating unit is used to update the speed and position of the following vehicle according to the expected acceleration of the following vehicle.

9. A vehicle cooperative control device, characterized in that: include: Memory for storing computer programs; A processor, used to execute the computer program to implement the steps of the vehicle cooperative control method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the vehicle cooperative control method as described in any one of claims 1 to 7.

Images