A method for downstream start-stop wave perception and suppression control based on vehicle platoon

Abstract

The application discloses a kind of downstream start-stop wave perception and inhibition control method based on car queue, belong to intelligent transportation technical field.The method is by constructing the error state coordinate based on spacing geometry strategy;By using laser radar, millimeter wave radar and Luenberger state observer, the complete state information estimation value of downstream external vehicle is estimated, and the complete state estimation value of downstream external vehicle is shared to the node vehicle with communication connection in the queue inside the queue inside vehicle networking;Establish the equivalent spring mass vibration model describing the car queue system, obtain the dynamic characteristic explanation and vibration response characteristic through vibration analysis and attenuation coefficient analysis, and select control gain based on the explanation and response characteristic, complete the inhibition of downstream vehicle start-stop wave and the motion control of queue system as a whole;The application makes the stability and safety of car queue itself and the following vehicle upstream of queue in traffic flow, improves the fluency and traffic efficiency of traffic flow.

Description

Technical Field

[0001] This invention relates to the field of intelligent transportation technology, specifically to a downstream start-stop wave sensing and suppression control method based on vehicle platooning. Background Technology

[0002] With the continuous popularization of connected vehicle technology and intelligent driving technology, vehicles driving on the road can not only obtain information about surrounding vehicles and road traffic environment through V2V and V2X networks, but also further plan their own movement based on this information, which further improves traffic efficiency and provides more adequate protection for traffic safety.

[0003] The acceleration, deceleration, braking, and starting of a car generate a wave in the traffic flow, collectively known as a start-stop wave. This wave can severely impact vehicles following in the same lane and the overall traffic flow, affecting both the smoothness of the traffic flow and the efficiency of road traffic. In more serious cases, it can even cause serious traffic accidents, endangering the safety of other vehicles and pedestrians.

[0004] Currently, conventional vehicle platoons primarily design their controllers based on the platoon's own performance. In addition, they can also target and suppress simple periodic downstream traffic waves. However, there is no suitable controller design theory to realize the perception, prediction, and suppression control of downstream start-stop waves for disturbances that involve uncertainty or non-periodicity.

[0005] To address the shortcomings of existing technologies, this invention proposes a downstream start-stop wave sensing and suppression control method based on vehicle queuing. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a downstream start-stop wave sensing and suppression control method based on vehicle queuing. This method has the functions of sensing downstream vehicle start-stop waves and safely suppressing downstream vehicle start-stop waves while ensuring the stability of the vehicle queuing through a queuing controller, thus ensuring safe vehicle operation. This solves the aforementioned technical problems.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a downstream start-stop wave sensing and suppression control method based on vehicle queuing, the specific steps of which are as follows:

[0008] S1. Construct error state coordinates based on spacing geometry strategy; according to vehicle physical parameters and queuing system, select spacing geometry strategy with fixed headway, calculate the expected following distance of the vehicle and define the expected position to obtain the vehicle error state coordinates.

[0009] As a preferred technical solution of the present invention, the step of converting the state of the node vehicle from ground coordinates to error state coordinates includes the following steps:

[0010] S1.1. Based on the specific traffic conditions, the physical attributes of the vehicles at the nodes, and the queue system N, a fixed headway spacing geometric strategy is adopted to calculate and select the desired following distance.

[0011] The specific traffic conditions include: fixed headway and fixed spacing.

[0012] The vehicle's physical properties include: vehicle safety range, vehicle motion state, and vehicle dynamic parameters;

[0013] The queue system N is the last vehicle in the queue system;

[0014] As a preferred embodiment of the present invention, the fixed headway geometry strategy in step S1.1 uses... Indicates node vehicle and adjacent vehicles Expected following distance, expected following distance The calculation formula is as follows:

[0015]

[0016] in, Indicates node vehicle Half of the safe range; Indicates adjacent vehicles Half of the safe range; For the node vehicle in step S1.1 In absolute coordinates, the absolute displacement relative to the origin of the absolute coordinate system; For node vehicles Absolute velocity in absolute coordinates; For node vehicles The fixed headway constant; For node vehicles The communication neighborhood, that is, the area in the car queue that can communicate with vehicles. The set of all vehicles that are communicating; For mathematical representation of nodal vehicles The adjacency matrix elements of the communication topology, if Then the vehicle With vehicles No communication; For the neighborhood In the middle, vehicles The fixed headway constant;

[0017] S1.2. Based on the selected desired following distance and the desired position of the reference vehicle outside the queue, define and obtain the desired position of each node vehicle, and transform the node vehicle state under a fixed headway into a dynamic value. (i.e., error states of each order) and expected value The sum of these values ​​is used to set the vehicle state of the node with a dynamic value of 0 to the 0-error position, thus obtaining the vehicle error state coordinates.

[0018] The error state coordinates include: displacement error state coordinates, velocity error state coordinates, and acceleration error state coordinates;

[0019] In step S1.2 of the present invention, the following is used Indicates vehicle When the queue is in a stable state, vehicles The position relative to the origin, i.e., the desired position, then the first... The expected position of a vehicle at a node is calculated using the following formula:

[0020]

[0021] in, Indicates the desired position of vehicle N. Indicates the first following vehicle outside the queue. (i.e., vehicles) The desired position of (located upstream in the queue, adjacent to vehicle N, but not included in the queue system). Indicates vehicle The distance between the vehicle and the Nth node vehicle within the queue;

[0022] As a preferred technical solution of the present invention, based on the definition of the desired position, for the vehicle In step S1.2, the vehicle The expression for the expected position is as follows:

[0023]

[0024]

[0025] As a preferred embodiment of the present invention, the fixed spacing geometric strategy in step S1.1 uses... Indicates node vehicle and adjacent vehicles The expected distance between them The calculation formula can be simplified from the fixed headway geometry strategy to a fixed spacing geometry strategy, as shown in the following expression:

[0026]

[0027] in, Indicates node vehicle Half of the safe range; Indicates adjacent vehicles Half of the safe range;

[0028] As a preferred technical solution of the present invention, for the first in the queue For each node vehicle, the error expression in step S1.2 is as follows:

[0029]

[0030] in, Representing node vehicles respectively Displacement error state coordinates, velocity error state coordinates, and acceleration error state coordinates during the vibration process. Indicates the desired speed. Indicates the expected acceleration. Indicates vehicle Absolute displacement relative to the origin of the coordinate system Indicates vehicle absolute speed, Indicates vehicle Absolute acceleration;

[0031] In addition to the fixed headway geometry strategy used in this invention to transform the state of a node vehicle from ground coordinates to error state coordinates, the method described in S1.2 is also applicable to transforming the state of a node vehicle from ground coordinates to error state coordinates based on a fixed spacing geometry strategy.

[0032] S2. Downstream State Perception and Information Sharing Based on State Observer: Based on vehicle error state coordinates, a dynamic model of the queuing system is obtained by combining the desired following distance and vehicle dynamics through a fixed-distance geometric strategy; partial state information of downstream external vehicles is obtained by using LiDAR and millimeter-wave radar sensors; the partial state information of downstream external vehicles is input, and the complete state information estimate of downstream external vehicles is estimated by using a Luenberger state observer; the complete state estimate of downstream external vehicles is input, and the complete state estimate of downstream external vehicles is shared with node vehicles with communication connections within the queuing through the vehicular network within the queuing;

[0033] As a preferred embodiment of the present invention, step S2 includes the following steps:

[0034] S2.1 Constructing the dynamic model of the queuing system; Based on the vehicle error state coordinates, through a fixed headway strategy, the desired following distance and vehicle dynamics are combined to obtain the dynamic model of the queuing system;

[0035] As a preferred technical solution of the present invention, in step S2.1, a dynamic model of the queuing system is established. Firstly, it is assumed that, under the conditions required by the present invention, for vehicles... Error state variables of each order: displacement error state coordinates Velocity error state coordinates and acceleration error state coordinates It is not required that it satisfies a differential relation, that is:

[0036]

[0037] in, This represents a differential operator that differentiates with respect to time; therefore, for the car queue under the aforementioned fixed-space geometry strategy, combined with... The calculation formulas for displacement error state coordinates, velocity error state coordinates, and acceleration error state coordinates satisfy the following conditions:

[0038]

[0039] in, , and These are the relative displacement, relative velocity, and relative acceleration in the error state coordinates of step S1.2, respectively. For vehicles with communication capabilities Relative acceleration;

[0040] control signal Input to jerk (i.e. acceleration) In the derivative of, that is:

[0041]

[0042] in, For vehicles Inertial time delay time constant; since all N vehicles in the queue satisfy the same vehicle dynamics relationship, then according to the vehicle... The overall dynamic model of the queue system, obtained by organizing the states of each order, is as follows:

[0043]

[0044] Among them, matrix It is an N-order identity matrix; matrix Represents the adjacency matrix of the communication topology; matrix This matrix represents the headway constants of all vehicles in the queue; This represents a matrix composed of the inertial time delay constants of vehicles at each node; For matrix The inverse matrix; matrix ,matrix ,matrix sum matrix All of these are control parameter matrices, and the values ​​of the matrix elements need to be determined based on the specific control strategy settings and communication network structure. This represents the Hadamard product operator;

[0045] S2.2, Perceiving downstream vehicle information: By using lidar and millimeter-wave radar sensors, partial status information of downstream external vehicles is obtained;

[0046] The aforementioned status information includes longitudinal spacing and longitudinal velocity;

[0047] First, this invention assumes that the prediction target is an external vehicle downstream (i.e., in front of the queue). The entire convoy followed the vehicles. Then proceed; preferably, in the specification of this invention, it is assumed that only vehicles are predicted. The longitudinal spacing and longitudinal velocity are unknown; furthermore, this specification only uses lidar and millimeter-wave radar sensors as illustrative examples to demonstrate the acquisition of vehicle data. The process of the corresponding state;

[0048] Preferably, the vehicle The longitudinal spacing and longitudinal velocity are respectively expressed as and Since the following distance can be converted into coordinates relative to the steady-state position using the coordinate transformation method described in step S1, the vehicle can be directly positioned... The relative displacement state replaces the longitudinal spacing;

[0049] S2.3 Input partial state information of downstream external vehicles, and estimate the complete state information of downstream external vehicles through the Luenberger state observer;

[0050] The complete state information estimate includes: estimated position, estimated velocity, estimated acceleration, and estimated disturbance.

[0051] This invention uses a Luenberger state observer to estimate the specific state of downstream external vehicles by utilizing partially observed state information; furthermore, in order to construct the vehicle... The dynamic equations of the vehicle, assuming the vehicle The movement pattern and the vehicles within the queue are consistent, and vehicles also need to be configured. accelerometer For a bounded unknown perturbation Furthermore, its derivative (i.e., higher-order perturbations) is a bounded unknown constant. Then the vehicle The dynamic equation The expression is:

[0052]

[0053] in, For the system matrix, For the input matrix, For the output matrix, For the merged state variables, The derivative of the merged state variables, Similarly For output variables, ,for Matrix transpose;

[0054] Downstream vehicles Estimates of all states , To estimate the location; To estimate the speed; To estimate acceleration; To estimate the disturbance; since the estimated value and the true value satisfy the same differential relationship, and only the longitudinal relative displacement... and longitudinal velocity Given, relative longitudinal acceleration Unknown, disturbance The basic principle of the Luenberger observer is based on known observations (referred to as "unknown" in this invention specification). and ) Correct vehicle Estimates of all states Thus, the estimated value Converging to the true value within the allowable range of error; defining the estimation error. The expression is:

[0055]

[0056] As a preferred technical solution of the present invention, based on the estimation error Definition and vehicles From the dynamic equations of the observer, we can obtain the following dynamic equations:

[0057]

[0058] in, The observer gain matrix; due to unknown perturbations and its higher-order perturbations For bounded unknowns, in the estimation error If the dynamic relationship is not satisfied, then for have:

[0059]

[0060] From the above, we can obtain the dynamic equation for the observer estimation error. for:

[0061]

[0062] in, The system matrix is ​​given by the observer error dynamics, and the gain matrix is ​​solved using the pole placement method. By taking the value of , an observer that meets the convergence requirement of the estimation error can be designed, so that the estimation error is dynamically stable; the dynamic equation of the observer is run to continuously correct the estimated value;

[0063] In addition to the specific sensors shown in this specification, the method described in S2.3 is also applicable to acquiring vehicle data using other sensors. The status information includes, but is not limited to, monocular / dual-lens cameras, GPS, and UWB positioning technology; in addition to the specific predictive variables shown in this specification, this method is also applicable to vehicle... Prediction of other state variables, including but not limited to longitudinal / lateral acceleration, lateral displacement, lateral velocity, steering angle, and steering angular acceleration.

[0064] As a preferred technical solution of the present invention, in step S2.3, the estimation of the complete state information of the downstream external vehicle by using the Luenberger state observer needs to be combined with the dynamic model in step S2.1 and the state variables to be predicted to derive the corresponding observer model.

[0065] S2.4 Input the complete state estimate of the downstream external vehicle, and share the complete state estimate of the downstream external vehicle with the node vehicle with communication connection within the queue through the vehicle network inside the queue;

[0066] As a preferred technical solution of the present invention, the vehicle network within the queue is shared with all communication-enabled nodes within the queue. The mathematical form of the specific topology of the vehicle network within the queue is a communication topology adjacency matrix. express:

[0067]

[0068] Among them, matrix The distribution of non-zero elements depends on the network structure, including but not limited to bidirectional (BD) structures, such as... Figure 3 As shown; Predecessor Following (PF) structure, such as Figure 4 As shown; Indicates with vehicles Vehicles with communication capabilities ; Satisfy the following expression:

[0069]

[0070] S3. Distributed Controller Setup and Vibration Suppression: Based on the vehicle error state coordinates, the vehicle control signal is obtained by setting the car-following control strategy of the distributed controller of the queuing system; by constructing an extended state space equation containing a state observer, and by establishing an equivalent spring mass vibration model, vibration analysis and attenuation coefficient analysis, the physical interpretation of the dynamic characteristics of the system, vibration response characteristics and selection of control gain are obtained to complete the suppression of the start-stop waves of downstream vehicles and the overall motion control of the queuing system.

[0071] As a preferred embodiment of the present invention, step S3 includes the following steps:

[0072] S3.1 Set the car-following control strategy of the queue system distributed controller; input the vehicle error state coordinates, and obtain the vehicle control signal by setting the car-following control strategy of the queue system distributed controller;

[0073] As a preferred embodiment of the present invention, the car-following control strategy of the queue system distributed controller in step S3.1 is to set only vehicle 1 in the entire queue to use the state observer to estimate the vehicle status. The motion state of vehicle 1, and other vehicles at nodes after vehicle 1, share state information and adjust their own motion state through the vehicle-to-everything (V2X) network within the queue in step S2.4; for vehicle 1, its control signal... The expression is:

[0074]

[0075] For vehicles at other nodes after vehicle 1, the control signal The expression is as follows:

[0076]

[0077] in, For node vehicles The communication neighborhood, For the communication neighborhood of node vehicle 1, For vehicles with communication capabilities, For adjacency matrix elements, For vehicle 1 and vehicle The displacement error control gain, Let be the displacement error state coordinates of vehicle 1. For vehicles Displacement error state coordinates, Let be the relative velocity of vehicle 1 in the error state coordinate system. For vehicles The relative velocity in the error state coordinate system. Let be the relative displacement of vehicle 1 in the error state coordinate system. The feedforward control gain is the displacement error between vehicle 1 and the downstream vehicle. For the estimated location of downstream vehicles, Let be the fixed headway constant for vehicle 1 at node . Let be the relative acceleration of vehicle 1 in the error state coordinate system. For the estimated speed of downstream vehicles, The speed error feedforward control gain between vehicle 1 and the downstream vehicle. For the estimated acceleration of downstream vehicles, For vehicles With vehicles The displacement error control gain, For vehicles Displacement error state coordinates, For vehicles Relative acceleration in the error state coordinate system;

[0078] S3.2 Construct the extended state-space equations that include the state observer;

[0079] The extended state space equations that include the state observer are constructed as follows: based on the dynamic model of the queue system, the state observer and the queue system distributed controller follow the car-following control strategy, and the extended state space equations are obtained by combining the state of the queue system and the state of the observer into an extended state vector.

[0080] As a preferred embodiment of the present invention, in step S3.2, establishing the extended state-space equations including the state observer first involves retrieving the state variables of the queue system from step S2.1. Replace with Then the dynamic equation becomes as follows:

[0081]

[0082] Then select As extended state variables, combined with the dynamic equation of the observer in step S2.3, and substituted into the expression for calculating the control signal in step S3.1, the extended state space equation can be obtained as follows:

[0083]

[0084] in As described in step S2.3, the remaining submatrices are:

[0085]

[0086]

[0087]

[0088]

[0089] S3.3 Based on the extended state-space equation, by establishing an equivalent spring-mass vibration model, vibration analysis and attenuation coefficient analysis, the physical interpretation of the dynamic characteristics of the system, vibration response characteristics and selection of control gain are obtained to complete the suppression of the start-stop wave of downstream vehicles and the overall motion control of the queue system.

[0090] As a preferred technical solution of the present invention, the establishment of an equivalent spring-mass vibration model in step S3.3 to analyze the vibration characteristics of the car queuing system under external disturbances is first based on the dynamic equation of the queuing system:

[0091]

[0092] This invention sets up a matrix sum matrix The following relationship must be satisfied:

[0093]

[0094] in, The first proportionality coefficient, This is the second proportionality coefficient; for vehicles The motion is assumed to be an interference signal. Then, the system dynamic equations are solved through decoupling operations. The system mechanical equations after the solution are obtained are:

[0095]

[0096] in, and These are the decoupled inertia matrix, velocity control gain matrix, and displacement control gain matrix, respectively, thus transforming the original system into a whole. A series of independent, single-degree-of-freedom damped forced vibration systems;

[0097] As a preferred technical solution of the present invention, the analysis of the vibration characteristics of the car platoon system under external disturbance in step S3.3 firstly, based on the mutually independent single-degree-of-freedom damped forced vibration system, the external force is expressed in the same form as the homomorphic solution, as follows:

[0098]

[0099] in, Indicates originating from a vehicle Interference signals, Indicates the amplitude of the interference signal. Indicates the angular frequency of the interference signal. Indicates the initial phase of the interference signal (i.e. Phase at time);

[0100] Substituting the homomorphic solution, we obtain the corresponding amplitude attenuation coefficient as follows:

[0101]

[0102] in, For the first Damping ratio, For the first The first vibration mode, and its corresponding expression is as follows:

[0103]

[0104]

[0105] Define the frequency ratio as Then we have:

[0106]

[0107] As a preferred embodiment of the present invention, in step S3.3, the control gain value is selected based on its own physical parameters, the motion and state information of adjacent vehicles obtained through communication, and the estimated state information of downstream external vehicles. This is equivalent to solving the matrix using the pole placement method. The values ​​of the observer control parameters are obtained by solving the calculation.

[0108] As a preferred technical solution of the present invention, in step S3.3, the control gain value is selected based on the vibration characteristic analysis results. Specifically, a suitable following distance is selected, and an attenuation coefficient that meets the requirements is set. At the same time, the queue controller matrix is ​​calculated based on the queue's own physical parameters, the motion and state information of adjacent vehicles obtained through communication, and the estimated state information of downstream external vehicles. ,matrix ,matrix sum matrix The control gain value.

[0109] Compared with existing technologies, this invention provides a downstream start-stop wave sensing and suppression control method based on vehicle queuing, which has the following beneficial effects:

[0110] (1) The present invention first proposes a method for sensing the start-stop waves of downstream external vehicles. This method obtains some motion and state information of downstream vehicles through sensors such as lidar and millimeter-wave radar. Then, the specific state estimate of downstream external vehicles is estimated by using the motion and state information obtained by the observation through a Luneburger observer. With the help of this sensor and observer, the queue system can realize the sensing of different forms of start-stop waves from downstream vehicles.

[0111] (2) This invention also proposes a new control gain design approach. This approach combines the start-stop wave information obtained from sensing, the specific communication topology network structure adopted by the vehicle queuing, the queuing geometric strategy, the physical parameters of the vehicles themselves at the queuing nodes, and the vibration characteristic analysis results to design a suitable vehicle queuing that can estimate the downstream vehicles. Motion status, and according to the vehicle The motion state adjustment queue internal node vehicle following distance is suppressed. The generated start-stop waves ensure the stability and safety of the car queues themselves and the vehicles following upstream in the queue, thereby improving the smoothness and efficiency of traffic flow. Attached Figure Description

[0112] Figure 1 This is a schematic diagram of the composition structure of the vehicle queuing system of the present invention;

[0113] Figure 2 This is a schematic diagram of the equivalent spring mass model of the present invention;

[0114] Figure 3 This is a schematic diagram of a BD-structured communication topology network queue according to the present invention;

[0115] Figure 4 This is a schematic diagram of a communication topology queue with a PF structure according to the present invention;

[0116] Figure 5 The attenuation coefficient of this invention varies with and A schematic diagram illustrating the changing pattern;

[0117] Figure 6 For the downstream vehicle interference signal of the present invention Schematic diagrams of modal response curves for each order, where (a) is the first-order modal response, (b) is the second-order modal response, (c) is the third-order modal response, (d) is the fourth-order modal response, (e) is the fifth-order modal response, (f) is the sixth-order modal response, (g) is the seventh-order modal response, and (h) is the eighth-order modal response.

[0118] Figure 7 This is a schematic diagram of the relative displacement curve of the BD structure queue model of the present invention, wherein (a) is the actual displacement response diagram of the queue, (b) is the relative displacement curve of the downstream interference signal, and (c) is the relative displacement curve of the upstream interference signal.

[0119] Figure 8 This is a schematic diagram of the relative velocity curve of the BD structure queue model of the present invention, wherein (a) is the actual displacement response diagram of the vehicle, (b) is the relative velocity curve of the downstream interference signal, and (c) is the relative velocity curve of the upstream interference signal. Detailed Implementation

[0120] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0121] Please see Figure 1-8 The present invention is based on a car queuing system with N cars, which includes four subsystems: node vehicle dynamics model, communication topology network, queue spacing geometry, and distributed controller.

[0122] Among them, the node vehicle dynamics model adopts the linear vehicle dynamics model, which is mainly used to describe the motion state of each node in the queue;

[0123] The communication topology network subsystem is mainly used to characterize the state information (such as position, speed, and acceleration) of each node vehicle shared between vehicles in the queue, as well as its transmission method and transmission direction;

[0124] The queue spacing geometry subsystem is mainly used to describe the car-following strategies adopted by vehicles at each node (such as fixed-gap car-following strategy and fixed-time-distance car-following strategy).

[0125] The distributed controller subsystem is mainly used to control the movement of vehicles at each node. The specific execution signals of the controller depend on the information provided by the three subsystems mentioned above.

[0126] like Figure 1 and Figure 2As shown, a downstream start-stop wave sensing and suppression control method based on vehicle queuing includes the following steps:

[0127] S1. Construct error state coordinates based on spacing geometry strategy; according to vehicle physical parameters and queuing system, select spacing geometry strategy with fixed headway, calculate the expected following distance of the vehicle and define the expected position to obtain the vehicle error state coordinates.

[0128] As a preferred technical solution of the present invention, the step of converting the state of the node vehicle from ground coordinates to error state coordinates includes the following steps:

[0129] S1.1. Based on the specific traffic conditions, the physical attributes of the vehicles at the nodes, and the queue system N, a spacing geometry strategy with a fixed headway is adopted to calculate and select the desired following distance.

[0130] The specific traffic conditions include: fixed headway and fixed spacing.

[0131] The vehicle's physical properties include: vehicle safety range, vehicle motion state, and vehicle dynamic parameters;

[0132] The queue system N is the last vehicle in the queue system;

[0133] As a preferred embodiment of the present invention, the fixed headway geometry strategy in step S1.1 uses... Indicates node vehicle and adjacent vehicles Expected following distance, expected following distance The calculation formula is as follows:

[0134]

[0135] in, Indicates node vehicle Half of the safe range; Indicates adjacent vehicles Half of the safe range; For the node vehicle in step S1.1 In absolute coordinates, the absolute displacement relative to the origin of the absolute coordinate system; For node vehicles Absolute velocity in absolute coordinates; For node vehicles The fixed headway constant; For node vehicles The communication neighborhood, that is, the area in the car queue that can communicate with vehicles. The set of all vehicles that are communicating; For mathematical representation of nodal vehicles The adjacency matrix elements of the communication topology, if Then the vehicle With vehicles No communication; For the neighborhood In the middle, vehicles The fixed headway constant.

[0136] S1.2. Based on the selected desired following distance and the desired position of the reference vehicle outside the queue, define and obtain the desired position of each node vehicle, and transform the node vehicle state under a fixed headway into a dynamic value. (i.e., error states of each order) and expected value The sum of these values ​​is used to set the vehicle state of the node with a dynamic value of 0 to the 0-error position, thus obtaining the vehicle error state coordinates.

[0137] The error state coordinates include: displacement error state coordinates, velocity error state coordinates, and acceleration error state coordinates;

[0138] In step S1.2 of the present invention, the following is used Indicates vehicle When the queue is in a stable state, vehicles The position relative to the origin, i.e., the desired position, then the first... The expected position of a vehicle at a node is calculated using the following formula:

[0139]

[0140] in, Indicates the desired position of vehicle N. Indicates the first following vehicle outside the queue. (i.e., vehicles) The desired position of (located upstream in the queue, adjacent to vehicle N, but not included in the queue system). Indicates vehicle The distance between the vehicle and the Nth node vehicle within the queue;

[0141] As a preferred technical solution of the present invention, based on the definition of the desired position, for the vehicle In step S1.2, the vehicle The expression for the expected position is as follows:

[0142]

[0143]

[0144] As a preferred embodiment of the present invention, the fixed spacing geometric strategy in step S1.1 uses... Indicates node vehicle and adjacent vehicles The expected distance between them The calculation formula can be simplified from the fixed headway geometry strategy to a fixed spacing geometry strategy, as shown in the following expression:

[0145]

[0146] in, Indicates node vehicle Half of the safe range; Indicates adjacent vehicles Half of the safe range;

[0147] As a preferred technical solution of the present invention, for the first in the queue For each node vehicle, the error expression in step S1.2 is as follows:

[0148]

[0149] in, Representing node vehicles respectively Displacement error state coordinates, velocity error state coordinates, and acceleration error state coordinates during the vibration process. Indicates the desired speed. Indicates the expected acceleration. Indicates vehicle Absolute displacement relative to the origin of the coordinate system Indicates vehicle absolute speed, Indicates vehicle The absolute acceleration.

[0150] S2. Downstream State Perception and Information Sharing Based on State Observer: Based on vehicle error state coordinates, a dynamic model of the queuing system is obtained by combining the desired following distance and vehicle dynamics through a fixed-distance geometric strategy; partial state information of downstream external vehicles is obtained by using LiDAR and millimeter-wave radar sensors; the partial state information of downstream external vehicles is input, and the complete state information estimate of downstream external vehicles is estimated by using a Luenberger state observer; the complete state estimate of downstream external vehicles is input, and the complete state estimate of downstream external vehicles is shared with node vehicles with communication connections within the queuing through the vehicular network within the queuing;

[0151] As a preferred embodiment of the present invention, step S2 includes the following steps:

[0152] S2.1 Constructing the dynamic model of the queuing system; Based on the vehicle error state coordinates, through a fixed headway strategy, the desired following distance and vehicle dynamics are combined to obtain the dynamic model of the queuing system;

[0153] As a preferred technical solution of the present invention, in step S2.1, a dynamic model of the queuing system is established. Firstly, it is assumed that, under the conditions required by the present invention, for vehicles... Error state variables of each order: displacement error state coordinates Velocity error state coordinates and acceleration error state coordinates It is not required that it satisfies a differential relation, that is:

[0154]

[0155] in, This represents a differential operator that differentiates with respect to time; therefore, for the car queue under the aforementioned fixed-space geometry strategy, combined with... The calculation formulas for displacement error state coordinates, velocity error state coordinates, and acceleration error state coordinates satisfy the following conditions:

[0156]

[0157] in, , and These are the relative displacement, relative velocity, and relative acceleration in the error state coordinates of step S1.2, respectively. For vehicles with communication capabilities Relative acceleration;

[0158] control signal Input to jerk (i.e. acceleration) In the derivative of, that is:

[0159]

[0160] in, For vehicles Inertial time delay time constant; since all N vehicles in the queue satisfy the same vehicle dynamics relationship, then according to the vehicle... The overall dynamic model of the queue system, obtained by organizing the states of each order, is as follows:

[0161]

[0162] Among them, matrix It is an N-order identity matrix; matrix Represents the adjacency matrix of the communication topology; matrix This matrix represents the headway constants of all vehicles in the queue; This represents a matrix composed of the inertial time delay constants of vehicles at each node; For matrix The inverse matrix; matrix ,matrix ,matrix sum matrix All of these are control parameter matrices, and the values ​​of the matrix elements need to be determined based on the specific control strategy settings and communication network structure. This represents the Hadamard product operator.

[0163] S2.2, Perceiving downstream vehicle information: By using lidar and millimeter-wave radar sensors, partial status information of downstream external vehicles is obtained;

[0164] The aforementioned status information includes longitudinal spacing and longitudinal velocity;

[0165] First, this invention assumes that the prediction target is an external vehicle downstream (i.e., in front of the queue). The entire convoy followed the vehicles. Then proceed; preferably, in the specification of this invention, it is assumed that only vehicles are predicted. The longitudinal spacing and longitudinal velocity are unknown; furthermore, this specification only uses lidar and millimeter-wave radar sensors as illustrative examples to demonstrate the acquisition of vehicle data. The process of the corresponding state;

[0166] Preferably, the vehicle The longitudinal spacing and longitudinal velocity are respectively expressed as and Since the following distance can be converted into coordinates relative to the steady-state position using the coordinate transformation method described in step S1, the vehicle can be directly... The relative displacement state replaces the longitudinal spacing.

[0167] S2.3 Input partial state information of downstream external vehicles, and estimate the complete state information of downstream external vehicles through the Luenberger state observer;

[0168] The complete state information estimate includes: estimated position, estimated velocity, estimated acceleration, and estimated disturbance.

[0169] This invention uses a Luenberger state observer to estimate the specific state of downstream external vehicles by utilizing partially observed state information; furthermore, in order to construct the vehicle... The dynamic equations of the vehicle, assuming the vehicle The movement pattern and the vehicles within the queue are consistent, and vehicles also need to be configured. accelerometer For a bounded unknown perturbation Furthermore, its derivative (i.e., higher-order perturbations) is a bounded unknown constant. Then the vehicle The dynamic equation The expression is:

[0170]

[0171] in, For the system matrix, For the input matrix, For the output matrix, For the merged state variables, The derivative of the merged state variables, Similarly For output variables, ,for Matrix transpose;

[0172] Downstream vehicles Estimates of all states , To estimate the location; To estimate the speed; To estimate acceleration; To estimate the disturbance; since the estimated value and the true value satisfy the same differential relationship, and only the longitudinal relative displacement... and longitudinal velocity Given, relative longitudinal acceleration Unknown, disturbance The basic principle of the Luenberger observer is based on known observations (referred to as "unknown" in this invention specification). and ) Correcting vehicles Estimates of all states Thus, the estimated value Converging to the true value Within the allowable range of nearby errors; define the estimation error. The expression is:

[0173]

[0174] As a preferred technical solution of the present invention, based on the estimation error Definition and vehicles From the dynamic equations of the observer, we can obtain the following dynamic equations:

[0175]

[0176] in, The observer gain matrix; due to unknown perturbations and its higher-order perturbations For bounded unknowns, in the estimation error If the dynamic relationship is not satisfied, then for have:

[0177]

[0178] From the above, we can obtain the dynamic equation for the observer estimation error. for:

[0179]

[0180] in, The system matrix is ​​given by the observer error dynamics, and the gain matrix is ​​solved using the pole placement method. By taking the value of , an observer that meets the convergence requirement of the estimation error can be designed, so that the estimation error is dynamically stable; by running the dynamic equation of the observer, the estimated value is continuously corrected.

[0181] As a preferred technical solution of the present invention, in step S2.3, the estimation of the complete state information of the downstream external vehicle by using the Luenberger state observer needs to be combined with the dynamic model in step S2.1 and the state variables to be predicted to derive the corresponding observer model.

[0182] S2.4 Input the complete state estimate of the downstream external vehicle, and share the complete state estimate of the downstream external vehicle with the node vehicle with communication connection within the queue through the vehicle network inside the queue;

[0183] As a preferred technical solution of the present invention, the vehicle network within the queue is shared with all communication-enabled nodes within the queue. The mathematical form of the specific topology of the vehicle network within the queue is a communication topology adjacency matrix. express:

[0184]

[0185] Among them, matrix The distribution of non-zero elements depends on the network structure, including but not limited to bidirectional (BD) and predecessor following (PF) structures. Indicates with vehicles Vehicles with communication capabilities ; Satisfy the following expression:

[0186]

[0187] As a preferred technical solution of the present invention, in this embodiment, the specific topology of the internal vehicle network adopts a bidirectional car-following structure (BD structure), and the adjacency matrix of the BD structure... for:

[0188] .

[0189] S3. Distributed Controller Setup and Vibration Suppression: Based on the vehicle error state coordinates, the vehicle control signal is obtained by setting the car-following control strategy of the distributed controller of the queuing system; by constructing an extended state space equation containing a state observer, and by establishing an equivalent spring mass vibration model, vibration analysis and attenuation coefficient analysis, the physical interpretation of the dynamic characteristics of the system, vibration response characteristics and selection of control gain are obtained to complete the suppression of the start-stop waves of downstream vehicles and the overall motion control of the queuing system.

[0190] As a preferred embodiment of the present invention, step S3 includes the following steps:

[0191] S3.1 Set the car-following control strategy of the queue system distributed controller; input the vehicle error state coordinates, and obtain the vehicle control signal by setting the car-following control strategy of the queue system distributed controller;

[0192] As a preferred embodiment of the present invention, the car-following control strategy of the queue system distributed controller in step S3.1 is to set only vehicle 1 in the entire queue to use the state observer to estimate the vehicle status. The motion state of vehicle 1, and other vehicles at nodes after vehicle 1, share state information and adjust their own motion state through the vehicle-to-everything (V2X) network within the queue in step S2.4; for vehicle 1, its control signal... The expression is:

[0193]

[0194] For vehicles at other nodes after vehicle 1, the control signal The expression is as follows:

[0195]

[0196] in, For node vehicles The communication neighborhood, For the communication neighborhood of node vehicle 1, For vehicles with communication capabilities, For adjacency matrix elements, For vehicle 1 and vehicle The displacement error control gain, Let be the displacement error state coordinates of vehicle 1. For vehicles Displacement error state coordinates, Let be the relative velocity of vehicle 1 in the error state coordinate system. For vehicles The relative velocity in the error state coordinate system. Let be the relative displacement of vehicle 1 in the error state coordinate system. The feedforward control gain is the displacement error between vehicle 1 and the downstream vehicle. For the estimated location of downstream vehicles, Let be the fixed headway constant for vehicle 1 at node . Let be the relative acceleration of vehicle 1 in the error state coordinate system. For the estimated speed of downstream vehicles, The speed error feedforward control gain between vehicle 1 and the downstream vehicle. For the estimated acceleration of downstream vehicles, For vehicles With vehicles The displacement error control gain, For vehicles Displacement error state coordinates, For vehicles Relative acceleration in the error state coordinate system.

[0197] S3.2 Construct the extended state-space equations that include the state observer;

[0198] The extended state space equations that include the state observer are constructed as follows: based on the dynamic model of the queue system, the state observer and the queue system distributed controller follow the car-following control strategy, and the extended state space equations are obtained by combining the state of the queue system and the state of the observer into an extended state vector.

[0199] As a preferred embodiment of the present invention, in step S3.2, establishing the extended state-space equations including the state observer first involves retrieving the state variables of the queue system from step S2.1. Replace with Then the dynamic equation becomes as follows:

[0200]

[0201] As a preferred technical solution of the present invention, the car queuing system used in this embodiment includes 8 node vehicles. However, the technical method provided by the present invention is also applicable to car queuings with other sizes of node vehicles, including but not limited to queuing sizes of 2, 4, and N vehicles. For the BD structure car queuing used in this embodiment, the inertial time delay time constant of each node vehicle... The matrix values ​​were selected as 0.8, 0.6, 0.5, 0.9, 0.7, 0.4, 0.3, and 0.2 respectively. middle:

[0202]

[0203]

[0204]

[0205]

[0206]

[0207]

[0208] in, For the displacement error feedforward control gain, For the speed error feedforward control gain, h The headway constant is fixed.

[0209] Then select As extended state variables, combined with the dynamic equation of the observer in step S2.3, and substituted into the expression for calculating the control signal in step S3.1, the extended state space equation can be obtained as follows:

[0210]

[0211] in As described in step S2.3, the remaining submatrices are:

[0212]

[0213]

[0214]

[0215] .

[0216] S3.3 Based on the extended state-space equation, by establishing an equivalent spring-mass vibration model, vibration analysis and attenuation coefficient analysis, the physical interpretation of the dynamic characteristics of the system, vibration response characteristics and selection of control gain are obtained to complete the suppression of the start-stop wave of downstream vehicles and the overall motion control of the queue system.

[0217] As a preferred technical solution of the present invention, the establishment of an equivalent spring-mass vibration model in step S3.3 to analyze the vibration characteristics of the car queuing system under external disturbances is first based on the dynamic equation of the queuing system:

[0218]

[0219] This invention sets up a matrix sum matrix The following relationship must be satisfied:

[0220]

[0221] in, The first proportionality coefficient, This is the second proportionality coefficient; for vehicles The motion is assumed to be an interference signal. Then, the system dynamic equations are solved through decoupling operations. The system mechanical equations after the solution are obtained are:

[0222]

[0223] in, and These are the decoupled inertia matrix, velocity control gain matrix, and displacement control gain matrix, respectively, thus transforming the original system into a whole. A series of independent, single-degree-of-freedom damped forced vibration systems;

[0224] As a preferred embodiment of the present invention, the analysis of the vibration characteristics of the car queuing system under external disturbances in step S3.3 first involves... Based on a mutually independent single-degree-of-freedom damped forced vibration system, the external force is expressed in the same form as the homomorphic solution, as follows:

[0225]

[0226] in, Indicates originating from a vehicle Interference signals, Indicates the amplitude of the interference signal. Indicates the angular frequency of the interference signal. Indicates the initial phase of the interference signal (i.e. (Phase of time).

[0227] After decoupling, in this embodiment of the invention, It contains 8 sub-components, and its initial phase Set to 0, amplitude The angular frequencies are shown in Table 1:

[0228] Table 1: Downstream Vehicle Interference Signal Modal Parameters

[0229]

[0230] Substituting the homomorphic solution, we obtain the corresponding amplitude attenuation coefficient as follows:

[0231]

[0232] in, For the first Damping ratio, For the first The first vibration mode, and its corresponding expression is as follows:

[0233]

[0234]

[0235] Define the frequency ratio as Then we have:

[0236]

[0237] As a preferred technical solution of the present invention, the following is selected according to Table 2. and ;

[0238] Table 2: Parameters of Frequency Ratio and Damping Ratio of Vibration System

[0239]

[0240] Subsequently, the vibration characteristics of each vehicle node in the decoupled system under different time delay constants and different external disturbances are analyzed using the attenuation coefficient. As a preferred technical solution of the present invention, in the embodiment... , For example, to show the attenuation coefficient as and The pattern of change, such as Figure 5 As shown.

[0241] As a preferred embodiment of the present invention, in step S3.3, the control gain value is selected based on its own physical parameters, the motion and state information of adjacent vehicles obtained through communication, and the estimated state information of downstream external vehicles. This is equivalent to solving the matrix using the pole placement method. The values ​​of the observer control parameters are obtained by solving the calculation.

[0242] As a preferred technical solution of the present invention, in step S3.3, the control gain value is selected based on the vibration characteristic analysis results. Specifically, a suitable following distance is selected, and an attenuation coefficient that meets the requirements is set. At the same time, the queue controller matrix is ​​calculated based on the queue's own physical parameters, the motion and state information of adjacent vehicles obtained through communication, and the estimated state information of downstream external vehicles. ,matrix ,matrix sum matrix The control gain value is selected according to the chosen value. And control gain, obtained Modal curves and nodal vehicle displacement simulation curves, velocity simulation curves, etc. Figure 6 and Figure 7 , Figure 8 As shown; Figure 6 For the downstream vehicle interference signal of the present invention Schematic diagrams of modal response curves for each order, where (a) is the first-order modal response, (b) is the second-order modal response, (c) is the third-order modal response, (d) is the fourth-order modal response, (e) is the fifth-order modal response, (f) is the sixth-order modal response, (g) is the seventh-order modal response, and (h) is the eighth-order modal response. Figure 7 This is a schematic diagram of the relative displacement curve of the BD structure queue model of the present invention, wherein (a) is the actual displacement response diagram of the queue, (b) is the relative displacement curve of the downstream interference signal, and (c) is the relative displacement curve of the upstream interference signal. Figure 8 This is a schematic diagram of the relative velocity curve of the BD structure queue model of the present invention. (a) is the actual displacement response diagram of the vehicle, (b) is the relative velocity curve of the downstream interference signal, and (c) is the relative velocity curve of the upstream interference signal. Under the BD communication structure, the queue can resist upstream and downstream interference at the same time and maintain the stability of displacement and velocity. Through vibration analysis and control gain design, the system achieves effective attenuation of traffic waves and improves the smoothness and safety of queue driving.

[0243] Compared with existing technologies, this invention provides a downstream start-stop wave sensing and suppression control method based on vehicle queuing, which has the following beneficial effects:

[0244] This invention first proposes a method for sensing start-stop waves from downstream external vehicles. This method acquires partial motion and state information of downstream vehicles using sensors such as lidar and millimeter-wave radar. Then, using a Luneburger observer, it estimates the specific state of the downstream external vehicles based on the observed motion and state information. With the help of this sensor and observer, the queuing system can sense different forms of start-stop waves from downstream vehicles.

[0245] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A downstream start-stop wave sensing and suppression control method based on vehicle platooning, characterized in that, Specifically, the following steps are included: S1. Construct error state coordinates based on spacing geometry strategy: Based on vehicle physical parameters and queuing system, select spacing geometry strategy with fixed headway, calculate the expected following distance of the vehicle and define the expected position to obtain the vehicle error state coordinates. S1.

1. Based on the specific traffic conditions, the physical attributes of vehicles at the nodes, and the queuing system, a spacing geometry strategy with a fixed headway is adopted to calculate and select the desired following distance. The specific traffic conditions include: fixed headway and fixed spacing. The physical properties of the vehicle include: vehicle safety range, vehicle motion state, and vehicle dynamic parameters; The queue system includes N vehicles; S1.

2. Based on the selected desired following distance and the desired position of the reference vehicle outside the queue, define and obtain the desired position, and transform the node vehicle state under a fixed headway into a dynamic value. Compared with expected value The sum of these values ​​is used, and the dynamic value is set to the preset error state to obtain the vehicle error state coordinates. The vehicle error state coordinates include: displacement error state coordinates, velocity error state coordinates, and acceleration error state coordinates; The spacing geometry strategy using a fixed headway in S1.1 calculates and selects the desired following distance in the following specific way: use Indicates node vehicle and adjacent vehicles Expected following distance, expected following distance The calculation formula is as follows: ； in, Indicates node vehicle Half of the safe range; Indicates adjacent vehicles Half of the safe range; For vehicles In absolute coordinates, the absolute displacement relative to the origin of the absolute coordinate system; For node vehicles Absolute velocity in absolute coordinates; For node vehicles The fixed headway constant; For node vehicles The communication neighborhood; For mathematical representation of nodal vehicles The adjacency matrix elements of the communication topology; For the neighborhood In the middle, vehicles The fixed headway constant; The method for obtaining the vehicle error state coordinates in S1.2 is as follows: using Indicates vehicle When the queue is in a stable state, vehicles The position relative to the origin, i.e., the desired position, then the first... The expected position of a vehicle at a node is calculated using the following formula: ； in, This represents the desired position of the Nth vehicle. Indicates the first following vehicle outside the queue. The expected position Indicates vehicle The distance between the vehicle and the Nth vehicle in the internal queuing system; Node vehicles The expression for the expected position is as follows: ； ； The calculation formula can be simplified from the fixed headway geometry strategy to a fixed spacing geometry strategy, as shown in the following expression: ； in, Indicates node vehicle Half of the safe range; Indicates adjacent vehicles Half of the safe range; The expressions for the displacement error state coordinates, velocity error state coordinates, and acceleration error state coordinates are as follows: ； in, Representing node vehicles respectively Displacement error state coordinates, velocity error state coordinates, and acceleration error state coordinates during the vibration process. Indicates the desired coordinates. Indicates the desired speed. Indicates the expected acceleration. Indicates node vehicle Absolute displacement coordinates relative to the origin. Indicates node vehicle absolute speed, Indicates node vehicle Absolute acceleration; S2. Downstream State Perception and Information Sharing Based on State Observer: Based on the vehicle error state coordinates, a dynamic model of the queuing system is obtained by combining the following distance and vehicle dynamics through a fixed headway spacing geometry strategy. Partial state information of downstream external vehicles is obtained through observation using lidar and millimeter-wave radar sensors. The partial state information of the downstream external vehicles is input, and the complete state information estimate of the downstream external vehicles is estimated using a Luneburg state observer. The complete state estimate of the downstream external vehicles is then shared with the communication-connected node vehicles within the queuing through the queuing's internal vehicle network. S3. Distributed Controller Setup and Vibration Suppression: Based on the vehicle error state coordinates, the vehicle control signal is obtained by setting the car-following control strategy of the distributed controller of the queuing system. By constructing an extended state space equation containing a state observer, and by establishing an equivalent spring mass vibration model, vibration analysis, and attenuation coefficient analysis, the physical interpretation of the system's dynamic characteristics and vibration response characteristics are obtained. Based on the physical interpretation and response characteristics, the control gain is selected to suppress the start-stop waves of downstream vehicles and to achieve the overall motion control of the queuing system.

2. The downstream start-stop wave sensing and suppression control method based on vehicle queuing according to claim 1, characterized in that, S2 includes the following steps: S2.1 Constructing the dynamic model of the queuing system; Based on the vehicle error state coordinates, through a fixed headway strategy, the desired following distance and vehicle dynamics are combined to obtain the dynamic model of the queuing system; S2.2, Perceiving downstream vehicle information: By using lidar and millimeter-wave radar sensors, partial status information of downstream external vehicles is obtained; The aforementioned status information includes longitudinal spacing and longitudinal velocity; S2.3 Input partial state information of downstream external vehicles, and estimate the complete state information of downstream external vehicles through the Luneburg state observer; The complete state information estimate includes: estimated position, estimated velocity, estimated acceleration, and estimated disturbance. S2.4 Input the complete state estimate of the downstream external vehicle, and share the complete state estimate of the downstream external vehicle with the node vehicles with communication connection within the queue through the vehicle network within the queue.

3. The downstream start-stop wave sensing and suppression control method based on vehicle platooning according to claim 2, characterized in that, The method for constructing the dynamic model of the queue system in S2.1 is as follows: For vehicles Error state variables of each order: displacement error state coordinates Velocity error state coordinates and acceleration error state coordinates It does not need to satisfy differential relations, vehicle absolute velocity and absolute acceleration The expression is as follows: ； in, Describes the differential operator that takes the derivative with respect to time. Indicates the desired coordinates. Indicates the desired speed. Indicates the expected acceleration. Indicates vehicle The absolute displacement coordinates relative to the origin; therefore, for a car queue under a fixed-space geometry strategy, combined with... The calculation formula for displacement error state coordinates Velocity error state coordinates and acceleration error state coordinates The states at each order satisfy: ； in, , and These represent the relative displacement, relative velocity, and relative acceleration in the error state coordinates, respectively. For vehicles with communication capabilities Relative acceleration; For node vehicles The communication neighborhood; For the neighborhood In the middle, vehicles The fixed headway constant; For mathematical representation of nodal vehicles The adjacency matrix elements of the communication topology; For node vehicles The fixed headway constant; control signal Input to The jerk is expressed as follows: ； in, For node vehicles Inertial time delay time constant; since all vehicles in the queue satisfy the same vehicle dynamics relationship, then according to the node vehicles The overall dynamic model of the queue system, obtained by organizing the states of each order, is as follows: ； Among them, matrix The order of the matrix is ​​set to the total number of vehicles in the queue, N; Represents the adjacency matrix of the communication topology; matrix This matrix represents the headway constants of all vehicles in the queue; This represents a matrix composed of the inertial time delay constants of vehicles at each node; For matrix The inverse matrix; matrix ,matrix ,matrix sum matrix All are control parameter matrices. This represents the Hadamard product operator, where N is the last vehicle in the queue system.

4. The downstream start-stop wave sensing and suppression control method based on vehicle platooning according to claim 2, characterized in that, The method for estimating the complete state information of downstream external vehicles in S2.3 is as follows: using a Luneburg state observer, the specific state estimates of downstream external vehicles are estimated by utilizing the partially observed state information of the downstream external vehicles; and a vehicle state is constructed. The dynamic equations of the vehicle, assuming the vehicle accelerometer There exists a bounded unknown perturbation ,and The derivative is a bounded unknown constant. Then the vehicle The dynamic equation The expression is: ； in, For the system matrix, For the input matrix, For the output matrix, To merge state variables, The derivative of the merged state variables, For output variables, Matrix transpose; Downstream vehicle V F Estimates of all states , To estimate the location; To estimate the speed; To estimate acceleration; To estimate the disturbance; since the estimated value and the true value satisfy the same differential relationship, and only the longitudinal relative displacement of the downstream vehicle is considered. and longitudinal velocity Given, relative longitudinal acceleration Unknown, disturbance The Luenberger observer is unknown; it corrects the downstream vehicle V based on known observations. F Estimates of all states Thus, the estimated value Converging to the true value within the allowable range of error; defining the estimation error. The expression is: ； The dynamic equation of the observer is: ； in, The observer gain matrix is... This is the output matrix; due to unknown perturbations and its higher-order perturbations For bounded unknowns, in the estimation error If the dynamic relationship is not satisfied, then for have: ； From the above, we can obtain the dynamic equation for the observer estimation error. for: ； in, This is the system matrix for the observer error dynamics.

5. The downstream start-stop wave sensing and suppression control method based on vehicle platooning according to claim 2, characterized in that, In S2.4, the method of sharing the complete state estimate of downstream external vehicles with the communication-connected node vehicles within the queue through the queue's internal vehicle network is as follows: It is shared with all communication-connected node vehicles within the queue through the queue's internal vehicle network. The mathematical form of the specific topology of the queue's internal vehicle network is the communication topology adjacency matrix. express: ； Among them, the adjacency matrix The order is N, which represents the total number of vehicles in the queuing system. For node vehicles, matrix The distribution of non-zero elements depends on the network structure, including but not limited to bidirectional car-following structures and lead-car-following structures; Indicates the vehicle at the node Vehicles with communication capabilities ; Satisfy the following expression: 。 6. The downstream start-stop wave sensing and suppression control method based on vehicle queuing according to claim 1, characterized in that, S3 includes the following steps: S3.1 Set the car-following control strategy of the queue system distributed controller; input the vehicle error state coordinates, and obtain the vehicle control signal by setting the car-following control strategy of the queue system distributed controller; S3.2 Construct the extended state-space equations that include the state observer; S3.3 Based on the extended state-space equation, by establishing an equivalent spring-mass vibration model, vibration analysis and attenuation coefficient analysis, the physical interpretation of the system's dynamic characteristics, vibration response characteristics and selection of control gain are obtained to complete the suppression of downstream vehicle start-stop waves and the overall motion control of the queuing system.

7. The downstream start-stop wave sensing and suppression control method based on vehicle platooning according to claim 6, characterized in that, The method for obtaining the vehicle control signal in S3.1 is as follows: input the vehicle error state coordinates, and set the car-following control strategy of the queue system distributed controller, setting only the first vehicle in the entire queue to use the state observer to estimate the downstream vehicles. The motion state of the vehicle, and the node vehicles with communication connections obtained by the other node vehicles after the first vehicle through step S2; for the control signal of vehicle 1 The expression is: ； For vehicles at nodes after the first one, the control signal... The expression is as follows: ； in, For node vehicles The communication neighborhood, For the communication neighborhood of the first vehicle, For vehicles with communication capabilities, For elements of the adjacency matrix, For the first vehicle and the vehicle with communication capability The displacement error control gain, Let be the displacement error state coordinates of vehicle 1. For vehicles with communication capabilities Displacement error state coordinates, Let be the relative velocity of the first vehicle in the error state coordinate system. For vehicles with communication capabilities The relative velocity in the error state coordinate system. Let be the relative displacement of vehicle 1 in the error state coordinate system. This is the feedforward control gain for the displacement error between the first vehicle and the downstream vehicle. For the estimated location of downstream vehicles, Let be the fixed headway constant of the first vehicle at node . Let be the relative acceleration of the first vehicle in the error state coordinate system. For the estimated speed of downstream vehicles, The feedforward control gain is the speed error between the first vehicle and the downstream vehicle. For the estimated acceleration of downstream vehicles, For node vehicles With communication vehicles The displacement error control gain, For node vehicles Displacement error state coordinates, For node vehicles Relative acceleration in the error state coordinate system; The method for constructing the extended state-space equations including the state observer in S3.2 is as follows: based on the dynamic model of the queue system, the state observer and the queue system's distributed controller follow the car-following control strategy, and by combining the state of the queue system and the state of the observer into an extended state vector, the extended state-space equations are obtained; the extended state-space equations... The expression is: ； in, To expand state variables, For higher-order perturbations, the bounded unknown constants, To expand the system matrix, For external measurement input matrix, The external perturbation input matrix is... This refers to the longitudinal spacing between downstream vehicles. This represents the longitudinal speed of the downstream vehicle.

8. The downstream start-stop wave sensing and suppression control method based on vehicle platooning according to claim 6, characterized in that, In S3.3, by establishing an equivalent spring-mass vibration model, performing vibration analysis and attenuation coefficient analysis, the physical interpretation of the system's dynamic characteristics, vibration response characteristics, and the method for selecting the control gain are as follows: velocity control gain matrix. and displacement control gain matrix The following relationship must be satisfied: ； in, The first proportionality coefficient, The second proportionality coefficient; matrix The matrix represents the inertial time delay constants of the vehicles at each node. The system dynamics equations are solved using decoupling operations. The resulting system mechanical equations are expressed as follows: ； in, and These are the decoupled inertia matrix, velocity control gain matrix, and displacement control gain matrix, respectively. This transforms the original system into a queuing system consisting of a total of 1,000 vehicles, each with independent single-degree-of-freedom damped forced vibrations. Relative acceleration error vector, Relative velocity error vector, Relative displacement error vector; This indicates interference signals originating from downstream vehicles; Based on mutually independent single-degree-of-freedom damped forced vibration systems, the external force is expressed in the same form as the homomorphic solution, as follows: ； in, This indicates interference signals from downstream vehicles. Indicates the amplitude of the interference signal. Indicates the angular frequency of the interference signal. This represents the initial phase of the interference signal, where t is a time variable.

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