CN106846832A - The optimal speed bootstrap algorithm in city signal intersection and system based on bus or train route collaboration - Google Patents

Abstract

The invention discloses an optimal vehicle speed guidance algorithm and a vehicle speed guidance system at urban signalized intersections based on vehicle-road coordination. The basic assumptions such as "vehicle speed guidance" are continuously updated according to the current position of the vehicle through the real-time refresh of the vehicle speed guidance system, which reduces the constraints of the model. At the same time, the influence of the low speed of the vehicle when turning is considered in the actual driving process. In the calculation, the deceleration process of the left-turning vehicle before reaching the stop line and the influence of the speed of the queuing dissipation vehicle passing the stop line is lower than that of going straight. The system of the present invention has completed the design and development of the vehicle speed guidance system from theoretical models to physical equipment, and proposed a set of feasible, mature and economical solutions under the current actual conditions, which can realize the basic vehicle-road coordination function at a relatively low price .

Description

Optimal vehicle speed guidance algorithm and system at urban signalized intersections based on vehicle-road coordination

technical field

The invention relates to an optimal vehicle speed guidance algorithm and a vehicle speed guidance system at urban signalized intersections based on vehicle-road coordination, and belongs to the technical field of intelligent transportation.

Background technique

With the continuous improvement of people's living standards, the penetration rate of vehicles is also increasing. According to statistics from the Traffic Management Bureau of the Ministry of Public Security, as of the end of 2016, the number of motor vehicles nationwide reached 290 million, including 194 million cars; there were 360 million motor vehicle drivers, including more than 310 million car drivers. The sharp increase of motor vehicles has brought enormous pressure to road traffic. Due to the great uncertainty of the driver's driving behavior, the blind choice of vehicle speed makes the road resources that are not abundant in the first place unable to be used efficiently. It requires the owner to start and stop frequently to pass a traffic light intersection, which wastes a lot of time and fuel, increases the wear and tear of the vehicle, and emits more exhaust gas into the atmosphere. How to provide drivers with road-friendly, economical and safe vehicle speed guidance is very important.

Due to the introduction of the concept of vehicle-road coordination, a new door has been opened for the development of intelligent transportation technology. The vehicle-road coordination system can effectively improve the transportation efficiency and road safety level. Driven by electronic information technology and wireless communication technology, the vehicle-road coordination system can realize the rapid, accurate and effective transmission of information within the system, and promote the Information exchange between roads. In a vehicle-road collaborative environment, the intelligent roadside system can obtain real-time traffic conditions and signal phase information at intersections, and enable vehicles to adjust their speed reasonably through speed guidance to improve the efficiency of intersection traffic. At present, the vehicle-road coordination technology generally stays in the research stage, and has not achieved large-scale practical application at home and abroad, and the existing vehicle speed guidance algorithm is not perfect enough. Many existing methods divide the effective green light time into N equal intervals based on the saturated headway, and guide each vehicle entering the control range to reach the stop line within a certain period of green light time. This guidance method requires each vehicle to reach the stop line within the expected time, and if one vehicle deviates, it will affect the following vehicles, resulting in failure of vehicle speed guidance. The linear programming model it adopts has fewer considerations and is not easy to solve.

Contents of the invention

Purpose of the invention: the purpose of the present invention is to overcome the deficiencies of the prior art and the imperfection of the implementation plan, propose the optimal vehicle speed guidance algorithm at the city signalized intersection, and design a complete set of vehicle speed guidance system, which can meet the requirements of each function Under such circumstances, the development of on-board control units and roadside control units can be realized at a relatively economical cost.

Technical solution: In order to achieve the above-mentioned purpose of the invention, the present invention adopts the following technical solutions:

An optimal vehicle speed guidance algorithm at an urban signalized intersection, comprising the following steps:

(1) If the target vehicle meets the maximum road speed limit and can reach the stop line before the end of the green light, and the queued vehicles in front can dissipate before the end of the green light in this cycle, it is considered that the target vehicle can pass the intersection within this signal cycle, Enter step (2), otherwise guide the target vehicle to slow down and stop and wait for the next cycle to pass through the intersection, and end;

(2) If the time required for the target vehicle to travel to the stop line at the maximum speed limit of the road is less than the queuing dissipation time of the vehicles in front of the queue, it is considered that the target vehicle can pass the intersection with the vehicles in front of the queue in the form of a convoy, and if so, guide the target vehicle to When the queued vehicles in front dissipate, reach the stop line, otherwise guide the target vehicle to pass as soon as possible.

further,

If _{t x} + _{t m} ≤ T is _satisfied , it is considered that the target vehicle can reach the stop line before the end of the green light while driving at the highest road speed limit; The cycle green light dissipates before the end; among them, T is the length of a signal cycle, t _x is the time from the current moment to the beginning of this cycle, t _m is the time required for vehicles to pass the intersection at the maximum speed limit of the road, and T _g is the time required for a cycle The phase length of the green light, h _s is the saturated headway, t _q is the dissipation time of the vehicles queued ahead;

For straight vehicles, a ₁ is the acceleration of the target vehicle when accelerating on the road section; v _m is the maximum speed limit of the road; v ₀ is the current speed of the target vehicle; L is the distance between the current position of the target vehicle and the stop line;

L _q is the queue length, a _ms is the vehicle startup acceleration, t _t is the startup loss time;

For left-turning or right-turning vehicles, considering that the vehicle speed is slow and there is a deceleration process before approaching the stop line, the modified t _m and t _q are:

Among them, v _left is the speed of left-turning vehicle; v _right is the speed of left-turning vehicle; a ₂ is the deceleration acceleration of the target vehicle on the road section. Further, if t _m ≤ T _r +t _q +h _s -t _x is satisfied, it is considered that the target vehicle can pass through the intersection with the queued vehicles ahead in a platoon.

Further, the guiding method for the target vehicle to reach the stop line when the queued vehicles in front have dissipated is as follows: The guiding method to guide the target vehicle to pass as soon as possible is: Among them, v _g is the speed of the guiding vehicle, v ₀ is the current speed of the target vehicle, L is the distance between the current position of the target vehicle and the stop line, T _r is the phase duration of the red light in a cycle, t _q is the dissipation time of the vehicles in front of the queue, h _s is Saturation headway, t _r is the driver's reaction time.

Further, the guiding target vehicle to decelerate and stop is to guide the vehicle to travel at an economical speed from the current moment, and the calculation method of the economical speed is:

Among them, a _com is the appropriate acceleration during the deceleration process of the vehicle, v ₀ is the current speed of the target vehicle, t _r is the driver's reaction time; a _slip is the sliding acceleration of the vehicle; t ₁ is the sliding time of the target vehicle, and L is the target vehicle The distance between the current position and the stop line, L _q is the queue length.

Further, for the situation where straight-going and right-turning share the same lane, the speed guidance of right-turning vehicles is corrected, including:

a. If you are going straight on a red light phase and there is no queued vehicle in front, you will be guided according to the normal right-turn speed guidance system in which the signal phase is green and the queued vehicles in front have dissipated;

b. Going straight on a red light phase and there are queuing vehicles in front, the right-turning vehicle will be restricted by the queuing vehicles and guided according to the speed of going straight;

c. Going straight on the green light phase, and the queued vehicles in front have not dissipated, guide the right-turning vehicle to reach the stop line and turn when the queued vehicles in front have dissipated, that is, the signal phase in the guidance system is green according to the normal speed, and the vehicle ahead Guidance is carried out by the guidance method that the queuing vehicles have not dissipated;

d. If the green light is on the straight line, and the vehicles in the queue ahead have dissipated, guide the right-turning vehicle in accordance with the normal speed guidance system in which the signal phase is green and the vehicles in the queue ahead have dissipated.

A speed guidance system for urban signalized intersections based on vehicle-road coordination and optimal vehicle speed guidance algorithms, including a vehicle-mounted terminal module and a roadside information exchange center module; wherein the vehicle-mounted terminal module and the roadside information exchange center module are connected through a wireless link , the roadside information exchange center module is used to obtain signal light timing information and vehicle queuing information, as well as receive vehicle position and vehicle speed information from the vehicle-mounted terminal, perform calculations to obtain the optimal vehicle speed suggested by the vehicle, and then feed back to the vehicle-mounted terminal module; the vehicle-mounted terminal The module is used to send vehicle position and vehicle speed information to the roadside information exchange center module in real time, and receive and display suggested vehicle speed.

Further, the vehicle-mounted terminal module includes: a GPS signal receiving module, a human-computer interaction module, a wireless communication module, and an MCU module; wherein the MCU module includes a GPS data processing unit, a wireless communication control unit, a display control unit, and a main control unit; the main The control unit is respectively connected with the GPS data processing unit, the wireless communication control unit and the display control unit, the GPS data processing unit is connected with the GPS signal receiving module, the display control unit is connected with the man-machine interaction module, and the wireless communication control unit is connected with the wireless communication module.

Further, the roadside information exchange center module includes: a queuing image acquisition module, a signal lamp control host computer, a wireless communication module, and an MCU module; wherein the MCU module includes an image processing unit, a core algorithm unit, a serial port communication unit, and a wireless communication control unit and the main control unit; the main control unit is respectively connected with the image processing unit, the core algorithm unit and the serial communication unit; the image processing unit is connected with the queuing image acquisition module to perform image processing and obtain the length of the queuing vehicle; the serial communication unit and the signal lamp control the upper computer Connected to obtain the timing information of the signal lights, the core algorithm unit is connected to the image processing unit and the serial communication unit respectively, and calculates the optimal speed of the vehicle according to the collected information.

Beneficial effect: compared with prior art, the advantage of the present invention is:

For the proposed optimal vehicle speed guidance algorithm, the vehicle speed guidance strategy proposed in the present invention does not include the basic assumptions in previous studies such as "vehicles are not allowed to overtake or change lanes, and all vehicles follow the speed guidance". , continuously calculate according to the current position of the vehicle, reducing the constraints of the model. At the same time, the influence of the low speed of the vehicle when turning is considered in the actual driving process. In the calculation, the deceleration process of the left-turning vehicle before reaching the stop line and the influence of the speed of the queuing dissipation vehicle passing the stop line is lower than that of going straight. Moreover, the influence of different entrance road configurations is considered, and the situation of different turning shared lanes is corrected, so that this guidance method is suitable for various intersections.

For the physical realization of the vehicle speed guidance system, the present invention has completed the design and development of the vehicle speed guidance system from the theoretical model to the physical equipment, and proposed a set of feasible, mature and economical solutions under the current actual conditions, which can be used relatively The low price realizes the basic vehicle-road coordination function.

Description of drawings

Fig. 1 is the algorithm flow chart of the present invention.

Figure 2 is a block diagram of system hardware implementation, including roadside information exchange center module and vehicle terminal module.

Fig. 3 is a schematic diagram of the specific implementation of the roadside information exchange center module.

Figure 4 is a schematic diagram of the specific implementation of the vehicle terminal module.

Figure 5 is a flow chart of the system work.

detailed description

As shown in Figure 1, it is a flow chart of the optimal guidance algorithm for urban signalized intersections disclosed in the embodiment of the present invention. No Pass through the intersection during this signal light cycle. If it is impossible to pass, guide the vehicle to stop at the end of the queue at an economical speed; if it is possible to pass the intersection, then judge whether it is necessary to guide the vehicle and the vehicle in front to pass in the form of a convoy, if not, then guide the vehicle to pass as soon as possible, if necessary When the form of a convoy passes through the intersection, the vehicles are guided to the stop line when the queue dissipates. After the above process is judged, the guide vehicle speed is calculated respectively.

As shown in Figure 2, it is a block diagram of hardware implementation of the vehicle speed guidance system of the present invention, and the optimal vehicle speed guidance system disclosed by the embodiment of the present invention includes the following components: vehicle-mounted terminal module and roadside information exchange center module; vehicle-mounted terminal module and roadside information exchange The modules communicate with each other through wireless channel links and carry out information transmission and interaction.

Among them, the vehicle terminal module includes four main physical modules: GPS signal receiving module 210 , human-computer interaction module (display screen) 214 , wireless communication module 209 , and MCU module 217 . The MCU module includes four logic units: GPS data processing unit 211 , wireless communication control unit 212 , display control unit 213 and main control unit 215 . The main control unit 215 is connected to the GPS data processing unit 211, the wireless communication control unit 212 and the display control unit 213 respectively, the GPS data processing unit 211 is connected to the GPS signal receiving module 210, the display control unit 213 is connected to the human-computer interaction module 214, wireless The communication control unit 212 is connected to the wireless communication module 209 . Figure 4 is a schematic diagram of the specific implementation of the vehicle terminal module. As shown in Figure 4, the MCU module MSP430 is the main body, which is connected to the GPS through a serial port to realize the modification of the GPS communication baud rate, the setting of the sampling frequency, and the filtering of the sending content, and the collected latitude and longitude, speed, heading, and real-time clock information Save it to the MCU module; the human-computer interaction module obtains the suggested speed and other information from the MCU module through the serial port, and displays the real-time speed and suggested speed to the driver in the form of an analog dashboard. The MCU module is connected with the wireless communication module through the SPI communication mode, and controls the wireless communication module to send and receive data. The debugging interface module is connected with the computer through the JTAG port. The power supply module is powered by a lithium battery that is chopper-boosted and then stabilized to 3.3v. In this embodiment, the GPS module in the vehicle terminal module is NEO-6M high-performance GPS, the wireless communication module is NRF24L01, the human-computer interaction module is a TFT color screen, and the MCU module is MSP430F5529.

The roadside information exchange center module includes 4 main physical modules: queuing image acquisition module 201, signal light control host computer 205, wireless communication module 208, MCU module 216; the MCU module includes 5 logic units: image processing unit 202, core Algorithm unit 203 , serial port communication unit 204 facing signal lamp host computer, wireless communication control unit 207 and main control unit 206 . Main control unit 206 is connected with image processing unit 202, core algorithm unit 203 and serial port communication unit 204 respectively; Image processing unit 202 is connected with queuing image acquisition module 201, carries out image processing, obtains the length of queuing vehicle; serial port communication unit 204 and signal light control The upper computer 205 is connected to obtain the timing information of the signal lights. The core algorithm unit 203 is respectively connected to the image processing unit 202 and the serial communication unit 204 to calculate the optimal speed of the vehicle according to the collected information. Figure 3 is a schematic diagram of the specific implementation of the roadside information exchange center module. As shown in Figure 3, the MCU module imports the image data from the queuing image acquisition module to the MCU module through DMA, performs image processing, and obtains the length of the queuing vehicles. The MCU module is connected with the signal lamp control host computer through the serial communication interface to obtain the timing information of the signal lamp. The MCU module is connected to the wireless communication module through SPI, and controls the orderly connection between the wireless communication module and the vehicle terminal to realize the collection of road vehicle position, speed, heading and other information and send the suggested speed to the vehicle. The roadside information exchange center module also includes a debugging interface module and a power supply module, and the debugging interface module is connected with a computer through a JTAG port. The power supply module is powered by a lithium battery that is chopper-boosted and then stabilized to 3.3v. In this embodiment, the queuing image acquisition module is an OV16860 sensor, the wireless communication module is NRF24L01, and the MCU module is MSP430F5529. MSP430 saves the image dot matrix data of the camera to the MCU for image processing through DMA; MSP430 obtains the signal light timing data from the signal light control host computer through RS232. MSP430 is connected to the wireless communication module through the SPI hardware in USCI_B to receive and send wireless signals.

The core algorithm unit in the above-mentioned roadside information exchange center module adopts the optimal vehicle speed guidance algorithm as follows:

1. Straight driving speed guidance

For vehicles within the guidance range, the vehicle speed guidance system mainly judges the way the vehicle passes through the intersection based on the vehicle's position, speed, current signal phase, and queuing situation in front of the stop line. When the following conditions are met, the target vehicle can pass through the intersection in this period, otherwise it needs to stop and wait for the next period.

t _x +t _m ≤ T (1)

t _q +h _s ≤ T _g (2)

Among them, t _x is the time length from the current moment to the beginning of this cycle; h _s is the saturated headway; T _g is the phase length of the green light in one cycle; T _r is the phase length of the red light in one cycle; T=T _r +T _g is the total duration of a signal cycle; t _m is the time required for vehicles to pass through the intersection at the maximum speed limit of the road; t _q is the dissipation time of vehicles queuing ahead. Equation (1) indicates that the vehicle can reach the stop line before the end of the green light when driving at the highest road speed limit, and Equation (2) indicates that the vehicles queuing in front can dissipate before the end of the green light in this cycle.

a ₁ is the acceleration of the target vehicle when accelerating on the road section; v _m is the maximum speed limit of the road; v ₀ is the current speed of the vehicle; L is the distance from the current position to the stop line; t _q0 is the queuing dissipation time excluding the start-up loss time ; L _q is the queue length; a _ms is the vehicle startup acceleration; t _t is the startup loss time.

a. Vehicles can pass through the intersection within this period. If the target vehicle can pass through the intersection within this period through the guidance of vehicle speed, the optimization goal is to guide the vehicle to pass without stopping to reduce the delay of passing through the intersection. On this basis, it is further judged whether the vehicle can pass through the intersection with the queued vehicles ahead in a platoon. When formula (5) is satisfied, that is, the time required for vehicles to travel to the stop line at the maximum speed limit of the road is less than the queuing dissipation time, the vehicles can follow the vehicles in front and pass in the form of a platoon.

t _m ≤T _r +t _q +h _s -t _x (5)

If the vehicle can pass in the form of a convoy with the vehicles in front, then guide the target vehicle to reach the stop line when the queued vehicles in front dissipate. The guidance method is as follows:

If the vehicle cannot pass in a convoy with the vehicle in front, that is, the queue has dissipated when driving to the stop line at the maximum speed limit on the road, guide the target vehicle to pass as soon as possible. The guidance method is as follows:

b. The vehicle needs to slow down and stop and wait for the next cycle to pass through the intersection. If the vehicle cannot reduce the single-vehicle delay through speed guidance, it will guide the vehicle to slow down and stop to the end of the queuing vehicle in an economical and energy-saving manner. From the current moment, the vehicle will be guided to drive at an economical speed. The calculation method of the economical speed is as follows:

Among them, a _com is the appropriate acceleration during the deceleration process of the vehicle, which can be set according to empirical values; t _r is the driver's reaction time; a _slip is the sliding acceleration of the vehicle; t ₁ is the sliding time of the target vehicle.

2. Speed guidance for left-turning and right-turning vehicles

In the actual driving process, there is a big difference between the left-turning vehicle and the straight-going vehicle in the steering process. This study is based on the execution algorithm, considering that the left-turning right-turning vehicle has a slow speed during the steering process and has a deceleration process before approaching the stop line. The calculated values of t _m and t _q are corrected.

a. Correction of t _m in different directions

Taking the speed guidance of a left-turning vehicle as an example, considering that there is a deceleration process before the vehicle reaches the stop line, the calculation method of t _m is obtained:

Among them, v _left is the speed of the left-turn vehicle; a ₂ is the deceleration acceleration of the target vehicle on the road section.

The speed guidance method of right-turning vehicles is the same as that of left-turning vehicles.

b. Correction of t _q in different directions

Taking the left-turning vehicle as an example, the turning speed of the left-turning vehicle is slower than that of going straight in the process of queuing and dissipating. The corresponding calculation method is as follows:

Among them, t _qleft0 is the left-turn queuing dissipation time excluding the start-up loss time.

The speed guidance for a right-turning vehicle is similar to that for a left-turning vehicle.

3. Speed guidance under different lane configurations

In the actual traffic environment, there are often situations where multiple turns share the same lane, and vehicles between different turns will be restricted by each other. In this study, the straight right lane is taken as an example to correct the speed guidance of right-turning vehicles.

a. If you are going straight on a red light phase and there is no queued vehicle in front, you will be guided according to the normal right-turn speed guidance system in which the signal phase is green and the queued vehicles in front have dissipated;

b. Going straight on a red light phase and there are queuing vehicles in front, the right-turning vehicle will be restricted by the queuing vehicles and guided according to the speed of going straight;

c. Going straight on the green light phase, and the queued vehicles in front have not dissipated, guide the right-turning vehicle to reach the stop line and turn when the queued vehicles in front have dissipated, that is, the signal phase in the guidance system is green according to the normal speed, and the vehicle ahead Guidance is carried out by the guidance method that the queuing vehicles have not dissipated;

d. If the green light is on the straight line, and the vehicles in the queue ahead have dissipated, guide the right-turning vehicle in accordance with the normal speed guidance system in which the signal phase is green and the vehicles in the queue ahead have dissipated.

In this embodiment, relevant empirical parameter values can be checked in the literature and selected according to experience when the algorithm is specifically calculated, such as: a _ms is ^2.78m /s for the vehicle starting acceleration; t _t is 1.5s for the starting loss time; v _left is 30m/s for left turning speed.

As shown in Figure 5, the specific working process of the vehicle speed guidance system of the present invention is as follows:

1) The roadside information exchange center module is initialized, communicates with the signal light control host computer, and obtains the real-time timing information of the signal light; at the same time, obtains the image from the vehicle queuing image acquisition module and calculates the current vehicle queuing length; after that, waits for the vehicle terminal module to be connected;

2) Initialize the vehicle terminal module, establish a connection with the roadside information exchange center module, and prepare for data transmission;

3) The vehicle-mounted terminal module packs and sends the vehicle's current location and vehicle speed information to the information exchange center module, and at the same time sends a request for obtaining the recommended optimal vehicle speed;

4) The roadside information exchange center module takes the received vehicle position and speed information sent by the vehicle terminal module, the current signal light timing information, the current vehicle queue length and the current intersection coordinates as parameters, and imports them into the suggested optimal vehicle speed algorithm for calculation ;

5) The roadside information exchange center module transmits the recommended optimal vehicle speed obtained from the calculation (can be calculated according to the three directions of left, straight and right, and push the three speeds at the same time) to the vehicle-mounted terminal module, and the vehicle-mounted terminal module will recommend the optimal vehicle speed in real time displayed to the user.

The vehicle speed guidance strategy proposed by the present invention overcomes the limitations of the traditional vehicle-road coordination model, and eliminates restrictions such as the inability to overtake and change lanes, making the model more in line with the actual road conditions and designing a complete set of vehicle speed guidance systems. Through product development using msp430 as the hardware platform to realize its main functional modules, and by comparing the total passing time of vehicles before and after guidance, it is concluded that the suggested speed calculated by the present invention has a higher driving reference value. Therefore, the vehicle-road coordination-based speed guidance algorithm and system of the present invention have great significance for improving the overall traffic efficiency of the road.

Claims (9)

1. the optimal speed bootstrap algorithm in a kind of city signal intersection, it is characterised in that comprise the following steps：

(1) if target vehicle meets can reach stop line with highest road speed limit traveling before green light terminates, and front is queued up Vehicle can dissipate before this cycle green light terminates and finish, then it is assumed that target vehicle can pass through intersection within this signal period, enter Enter step (2), otherwise guiding target vehicle deceleration stops and waits next cycle by intersection, terminates；

(2) disappear if target vehicle meets to travel to stop line required time to be queued up less than front queuing vehicle with road Maximum speed limit The time of dissipating, then it is assumed that target vehicle can pass through intersection with front queuing vehicle in fleet's form, if then guiding target car Front queuing vehicle dissipate finish when reach stop line, otherwise guiding target vehicle passes through as early as possible.

2. the optimal speed bootstrap algorithm in a kind of city signal intersection according to claim 1, it is characterised in that：

If meeting t_x+t_m≤ T, then it is assumed that target vehicle can reach stop line with highest road speed limit traveling before green light terminates；If Meet t_q+h_s≤T_g, then it is assumed that target vehicle front queuing vehicle can dissipate before this cycle green light terminates and finish；Wherein, T is One signal period duration, t_xIt is the duration that current time starts away from this cycle, t_mFor vehicle with road Maximum speed limit by intersecting The time required to mouthful, T_gIt is green light phase duration, h in a cycle_sIt is saturation headway, t_qWhen being dissipated for front queuing vehicle Between；

For through vehicles,a₁It is acceleration of the target vehicle when section accelerates；v_mIt is road Road Maximum speed limit；v₀It is target vehicle present speed；L is target vehicle current location apart from stop line distance；

L_qIt is queue length, a_msIt is vehicle launch acceleration, t_tTo start the loss time；

For left-hand rotation or right-turning vehicles, it is considered to which speed is slower and has moderating process before stop line, to t_mAnd t_qIt is after amendment：

$t_{mleft}=\left\{\begin{array}{cc}\frac{L}{v_m}+\frac{{(v_m-v_0)}^2}{2a_1{v}_m}+\frac{{(v_m-v_{left})}^2}{2a_2{v}_m}& \frac{v_m^2-v_0^2}{2a_1}+\frac{v_m^2-v_{left}^2}{2a_2}<L\\ \frac{a_1{a}_2}{a_1+a_2}\sqrt{\frac{a_2{v}_0^2+a_1{v}_{left}^2+2a_1{a}_{2}L}{a_2-a_1}}-\frac{v_0}{a_1}-\frac{v_{left}}{a_2}& \frac{v_0^2-v_{left}^2}{2a_2}\&le;L\\ \frac{2L}{v_0+v_{left}}& \frac{v_0^2-v_{left}^2}{2a_2}\&GreaterEqual;L\end{array}\right.$

$t_{qleft}=t_t+\frac{2L_q}{v_{left}}$

$t_{mright}=\left\{\begin{array}{cc}\frac{L}{v_m}+\frac{{(v_m-v_0)}^2}{2a_1{v}_m}+\frac{{(v_m-v_{right})}^2}{2a_2{v}_m}& \frac{v_m^2-v_0^2}{2a_1}+\frac{v_m^2-v_{right}^2}{2a_2}<L\\ \frac{a_1{a}_2}{a_1+a_2}\sqrt{\frac{a_2{v}_0^2+a_1{v}_{right}^2+2a_1{a}_{2}L}{a_2-a_1}}-\frac{v_0}{a_1}-\frac{v_{right}}{a_2}& \frac{v_0^2-v_{right}^2}{2a_2}\&le;L\\ \frac{2L}{v_0+v_{right}}& \frac{v_0^2-v_{right}^2}{2a_2}\&GreaterEqual;L\end{array}\right.$

$t_{qright}=t_t+\frac{2L_q}{v_{right}}$

Wherein, v_leftIt is left-hand rotation speed；v_rightIt is left-hand rotation speed, a₂For the acceleration that target vehicle slows down in section.

3. the optimal speed bootstrap algorithm in a kind of city signal intersection according to claim 2, it is characterised in that：

If meeting t_m≤T_r+t_q+h_s-t_x, then it is assumed that target vehicle can pass through intersection with front queuing vehicle in fleet's form.

4. the optimal speed bootstrap algorithm in a kind of city signal intersection according to claim 2, it is characterised in that：

The guiding target vehicle front queuing vehicle dissipate finish when reach stop line guidance mode be： The guidance mode that the guiding target vehicle passes through as early as possible is： Wherein, v_gIt is guiding speed, v₀It is target vehicle present speed, L is target vehicle current location apart from stop line distance, T_rFor Red light phase duration, t in a cycle_qIt is front queuing vehicle resolution time, h_sIt is saturation headway, t_rFor driver is anti- Between seasonable.

5. the optimal speed bootstrap algorithm in a kind of city signal intersection according to claim 1, it is characterised in that：

The guiding target vehicle deceleration parking is that vehicle is guided since current time with economy cruising, guiding speed Calculation：

$v_g=\left\{\begin{array}{cc}{v}_0-\frac{v_0^2\&CenterDot;t_r}{2(L-L_q)}& \frac{v_0^2}{2a_{com}}>L-L_q\\ v_0+a_{slip}{t}_r& \frac{v_0^2}{2a_{slip}}>L-L_q\\ v_0-a_{slip}(t_r-t_1)& \frac{v_0^2}{2a_{slip}}\&le;L-L_q\end{array}\right.$

Wherein, a_comSuitable acceleration in for vehicle deceleration process, v₀It is target vehicle present speed, t_rWhen being reacted for driver Between；a_slipAcceleration is slided for vehicle；t₁It it is the time that target vehicle is slided, L is target vehicle current location apart from stop line Distance, L_qIt is queue length.

6. the optimal speed bootstrap algorithm in a kind of city signal intersection according to claim 1, it is characterised in that：For straight Row and the shared situation in track of turning right, are modified to the guiding of right-turning vehicles speed, including：

A. straight trip behavior red light phase and front without queuing vehicle, then according to signal phase in normal right-hand rotation speed guiding system For green, and the queuing vehicle guidance mode for finishing that dissipated in front is guided；

B. straight trip behavior red light phase and there is queuing vehicle in front, then right-turning vehicles will be limited by queuing vehicle, according to straight Capable speed guiding is guided；

C. straight trip behavior green light phase, and front queuing vehicle does not dissipate and finishes, then guide the right-turning vehicles in front queuing car To dissipate reach when finishing and stop line and turned to, i.e., be green and preceding according to signal phase in normal speed guiding system The square queuing vehicle guidance mode for finishing that do not dissipate is guided；

D. straight trip behavior green light phase, and front queuing vehicle has dissipated and has finished, then guide the right-turning vehicles according to normal car Signal phase is for green in fast guiding system, and the queuing vehicle guidance mode for finishing that dissipated in front is guided.

7. it is based on using one kind of the optimal speed algorithm of city signal intersection speed according to claim any one of 1-6 The city signal intersection speed guiding system of bus or train route collaboration, it is characterised in that：Handed over including car-mounted terminal module and roadside information Switching center9's module；Wherein car-mounted terminal module is attached with roadside message switching center module by Radio Link, roadside letter Breath switching centre module is used to obtain traffic signal timing information and vehicle queue information, and receives the car that car-mounted terminal is sent Position and speed information, carry out computing and show that vehicle feeds back to car-mounted terminal module after advising optimal speed；Car-mounted terminal mould Block is used to send vehicle location and speed information to roadside message switching center module in real time, and receives suggestion speed and show Show.

8. a kind of city signal intersection speed based on bus or train route collaboration according to claim 7 guides system, its feature It is：The car-mounted terminal module includes：Gps signal receiver module, human-computer interaction module, wireless communication module and MCU module； Wherein MCU module includes gps data processing unit, wireless communication control unit, display control unit and main control unit；Master control list Unit be connected with gps data processing unit, wireless communication control unit and display control unit respectively, gps data processing unit and Gps signal receiver module is connected, and display control unit is connected with human-computer interaction module, wireless communication control unit and radio communication Module is connected.

9. a kind of city signal intersection speed based on bus or train route collaboration according to claim 7 guides system, its feature It is：The roadside message switching center module includes：Queuing image collection module, Signalized control host computer, radio communication Module, MCU module；Wherein MCU module includes graphics processing unit, core algorithm unit, serial communication unit, radio communication control Unit processed and main control unit；Main control unit is connected with graphics processing unit, core algorithm unit and serial communication unit respectively；Figure As processing unit is connected with queuing image collection module, image procossing is carried out, obtain queuing vehicle length；Serial communication unit with Signalized control host computer be connected, obtain signal lamp timing information, core algorithm unit respectively with graphics processing unit and string Port communications unit is connected, and the information according to collection calculates the optimal velocity of vehicle.