Disclosure of Invention
In view of the above, the invention aims to provide a system and a method for guiding the speed of a heterogeneous traffic flow of an expressway entrance ramp, so as to solve the problem that most of the current speed guiding systems and methods of the entrance ramp are concentrated on homogeneous traffic flows with the same intelligent degree, and the problem that heterogeneous traffic flows such as intelligent vehicles, internet-connected vehicles and common vehicles are mixed in the long term in the future is not considered.
In order to achieve the above purpose, the technical scheme of the invention is realized as follows:
a highway entrance ramp heterogeneous traffic flow speed guidance system, comprising:
The intelligent vehicle-mounted subsystem is used for acquiring intelligent vehicle information and is arranged on an intelligent vehicle; the network-connected vehicle-mounted subsystem is used for acquiring network-connected vehicle information and is arranged on a network-connected vehicle; the system comprises a common vehicle information acquisition subsystem for acquiring common vehicle information, wherein the common vehicle information acquisition subsystem is arranged on a road side;
the intelligent vehicle-mounted subsystem, the internet-connected vehicle-mounted subsystem and the common vehicle information acquisition subsystem are all in wireless connection with the road side speed decision-making subsystem, the road side speed decision-making subsystem guides vehicles according to the sequence, and the road side decision-making subsystem is also connected with the road side display screen display subsystem.
Further, the intelligent vehicle-mounted subsystem comprises a vehicle-mounted storage and wireless communication module, and a vehicle speed acquisition module, a GPS positioning module, a voice broadcasting module, a vehicle speed information display module, a brake and accelerator control module, a steering control module and a vehicle basic information storage module which are connected with the vehicle-mounted storage and wireless communication module;
The intelligent vehicle-mounted subsystem is in wireless connection with the road side speed decision-making subsystem through the vehicle-mounted storage and wireless communication module.
Further, the network-connected vehicle-mounted subsystem comprises a vehicle-mounted storage and wireless communication module, and a vehicle speed acquisition module, a GPS positioning module, a vehicle-mounted wireless communication module, a vehicle basic information storage module, a vehicle speed display module and a voice broadcasting module which are connected with the vehicle-mounted storage and wireless communication module;
The intelligent vehicle-mounted subsystem is in wireless connection with the road side speed decision-making subsystem through the vehicle-mounted storage and wireless communication module.
Further, the common vehicle information acquisition subsystem comprises a storage and wireless communication module, and a license plate shooting acquisition module, a position shooting acquisition module and a vehicle speed shooting acquisition module which are connected with the storage and wireless communication module;
the common vehicle information acquisition subsystem is connected with the road side speed decision subsystem through the storage and wireless communication module.
Further, the road side speed decision subsystem comprises a road side wireless communication module, a passing sequence service module connected with the road side wireless communication module, and an intelligent vehicle moving blocking speed calculation module, a network vehicle fixed blocking speed calculation module and a common vehicle fixed blocking speed calculation module connected with the passing sequence service module.
Further, the road side display screen display subsystem comprises a communication module, a guide information display module and a guide information voice playing module, wherein the guide information display module and the guide information voice playing module are connected with the communication module;
The communication module is a wireless or wired communication module.
A method for guiding the speed of a heterogeneous traffic flow of an expressway entrance ramp comprises the following steps:
s1, when a vehicle reaches a communication range of a road side speed decision subsystem, the road side speed decision subsystem acquires vehicle information;
S2, the road side speed decision subsystem receives the transmission information, distributes the passing right of the conflict point of the merging area according to the first-come first-serve principle, and arranges the passing sequence of all vehicles of the main road and the entrance ramp;
S3, the road side speed decision subsystem calculates a guiding speed v;
and S4, after the speed calculation is completed, the speed guiding center sends guiding information to the vehicles in the communication range.
Further, in the step S1, the method for obtaining the vehicle information by the road side speed decision subsystem is as follows:
The vehicle-mounted subsystems of the intelligent vehicle and the internet-connected vehicle interact with the road side speed decision subsystem, vehicle information is sent to the road side speed decision subsystem, and vehicle information of the common vehicle is acquired by the common vehicle information acquisition subsystem arranged on the road side and is sent to the road side speed decision subsystem.
Further, in the step S3, the guiding speed v is calculated by adopting a fixed blocking method for the common vehicle and the internet-connected vehicle, and the intelligent vehicle calculates the guiding speed v by adopting a moving blocking method, which comprises the following specific steps:
Aiming at the intelligent vehicle, the speed control precision is higher because the intelligent vehicle is controlled by a driving robot, a mobile blocking control method in a blocking interval theory is adopted, the passing time of a front vehicle in a passing sequence is taken as a target point, the predicted passing time of the vehicle is calculated and remembered according to the position and the speed of the vehicle, and the guiding speed is obtained by back-pushing;
The estimated passing time tpass of the intelligent vehicle has the following calculation formula:
Wherein treach is the time when the vehicle arrives at the communication range of the road side decision system, vi is the guiding speed of the vehicle, v0 is the speed when the vehicle arrives at the communication range, a is the acceleration of the vehicle, and x is the distance between the vehicle and the conflict point of the converging region;
According to the mobile occlusion control method, the estimated passing time of the previous vehicle is taken as a target point, and the estimated passing time tpass of the intelligent vehicle is as follows:
Where tpass-f is the expected passing time of the preceding vehicle in the order, tbrake is the shortest braking time of the vehicle, and tsafe is the safety time margin.
The two are combined, and the guiding speed of the vehicle i under the acceleration condition can be obtained:
The guiding speed of the vehicle i in the deceleration condition is:
wherein t isi＝tpass-f+tsafe-treach
For the network-connected vehicle, the vehicle is controlled by a driver, and the speed control precision is low, so that a fixed blocking control method is adopted, the passing time of the preceding vehicle in sequence is taken as a target point, and the predicted passing time and the guiding speed of the vehicle are obtained according to fixed length calculation;
The estimated passing time tpass, of the internet protocol vehicle has the following calculation formula:
Wherein treaction is the reaction time of the driver to the speed guiding information;
Taking the estimated passing time of the preceding vehicle in sequence as an end point of one end of the section and taking the safety headway as the section length tf of the fixed block, the estimated passing time tpass of the own vehicle is:
tpass＝ti-1+tf
the two are combined, and the guiding speed of the vehicle i under the condition of deceleration can be obtained:
Guiding speed of vehicle i under acceleration:
Wherein t=tpass-f+tf-treach-treaction
For common vehicles, the vehicle is controlled by a driver, and the speed control precision is low, so that a fixed blocking control method is also adopted, and the information of the common vehicle is acquired and sent with delay, so that the calculation method of the section length is different from that of the network-connected vehicle;
the calculation formula of the passing time of the common vehicle is as follows:
taking the estimated passing time of the preceding vehicle in the sequence as a target point, and fixing the blocked interval length as a safe headway time and the guiding speed on a driver reading display screen, wherein the estimated passing time of the vehicle is as follows:
tpass＝ti-1+tf+tread
the two are combined, and the guiding speed of the vehicle i under the condition of deceleration can be obtained:
Where the guiding speed of the vehicle i under acceleration:
Wherein t=ti-1+tf-treach-tsafe-treaction.
Further, in the step S4, the method for guiding the vehicle is as follows:
Guiding the intelligent vehicle to automatically drive and displaying guiding information to a vehicle user; the internet-enabled vehicle informs the information to the driver through vision and hearing; and meanwhile, the guiding information of the common car is visually and aurally broadcasted through the road side display screen.
Compared with the prior art, the system and the method for guiding the speed of the heterogeneous traffic flow of the expressway entrance ramp have the following advantages:
(1) The system for guiding the speed of the heterogeneous traffic flow of the expressway entrance ramp is provided by the invention, and can be used for rapidly guiding the vehicles on the expressway entrance ramp, and effectively solving the problem that the vehicles are easy to block at the entrance of the ramp by utilizing different subsystems aiming at different vehicles.
(2) The invention creates the method for guiding the speed of the highway entrance ramp heterogeneous traffic flow, which adopts different guiding speed calculation methods aiming at vehicles with different intelligent networking degrees, and adopts a more efficient moving blocking speed calculation method aiming at intelligent vehicles with higher intelligent networking degrees. Aiming at common vehicles and internet-connected vehicles, a fixed blocking speed calculation method is adopted. The system and the method can effectively reduce collision risk of the confluence area and improve traffic efficiency by guiding the speed of the individual vehicles. Meanwhile, the method aims at heterogeneous traffic flow environment and adopts a combined blocking interval control method, so that the method has the characteristics of strong practicability, long applicable period and high robustness.
Detailed Description
In order to more clearly illustrate the present invention, the present invention will be further described with reference to the preferred embodiments and the accompanying drawings. It is to be understood by persons skilled in the art that the following detailed description is illustrative and not restrictive, and that this invention is not limited to the details given herein.
As shown in fig. 2, a system for guiding a speed of a heterogeneous traffic flow of an entrance ramp of an expressway includes:
The intelligent vehicle-mounted subsystem is used for acquiring intelligent vehicle information and is arranged on an intelligent vehicle; the network-connected vehicle-mounted subsystem is used for acquiring network-connected vehicle information and is arranged on a network-connected vehicle; the system comprises a common vehicle information acquisition subsystem for acquiring common vehicle information, wherein the common vehicle information acquisition subsystem is arranged on a road side;
the intelligent vehicle-mounted subsystem, the internet-connected vehicle-mounted subsystem and the common vehicle information acquisition subsystem are all in wireless connection with the road side speed decision-making subsystem, the road side speed decision-making subsystem guides vehicles according to the sequence, and the road side decision-making subsystem is also connected with the road side display screen display subsystem.
The intelligent vehicle-mounted subsystem comprises a vehicle-mounted storage and wireless communication module, and a vehicle speed acquisition module, a GPS positioning module, a voice broadcasting module, a vehicle speed information display module, a brake and accelerator control module, a steering control module and a vehicle basic information storage module which are connected with the vehicle-mounted storage and wireless communication module;
The intelligent vehicle-mounted subsystem is in wireless connection with the road side speed decision-making subsystem through the vehicle-mounted storage and wireless communication module.
The network-connected vehicle-mounted subsystem comprises a vehicle-mounted storage and wireless communication module, and a vehicle speed acquisition module, a GPS positioning module, a vehicle-mounted wireless communication module, a vehicle basic information storage module, a vehicle speed display module and a voice broadcasting module which are connected with the vehicle-mounted storage and wireless communication module;
The intelligent vehicle-mounted subsystem is in wireless connection with the road side speed decision-making subsystem through the vehicle-mounted storage and wireless communication module.
The common vehicle information acquisition subsystem comprises a storage and wireless communication module, and a license plate shooting acquisition module, a position shooting acquisition module and a vehicle speed shooting acquisition module which are connected with the storage and wireless communication module;
the common vehicle information acquisition subsystem is connected with the road side speed decision subsystem through the storage and wireless communication module.
The road side speed decision subsystem comprises a road side wireless communication module, a passing sequence service module connected with the road side wireless communication module, and an intelligent vehicle moving blocking speed calculation module, a network vehicle fixed blocking speed calculation module and a common vehicle fixed blocking speed calculation module connected with the passing sequence service module.
The road side display screen display subsystem comprises a communication module, a guide information display module and a guide information voice playing module, wherein the guide information display module and the guide information voice playing module are connected with the communication module;
The communication module is a wireless or wired communication module.
It should be noted that, the vehicle-mounted subsystem of the intelligent vehicle, the network-connected vehicle-mounted subsystem, the common vehicle information acquisition subsystem, the road side speed decision subsystem and the road side display screen display subsystem can all be realized by adopting the prior art, for example, a vehicle speed acquisition module, a GPS positioning module, a vehicle speed information display module, a voice playing module, an accelerator and brake control module and a steering control module of the vehicle-mounted subsystem of the intelligent vehicle are similar to the functions of a Cadilac super cryise system.
The vehicle basic information storage module of the intelligent vehicle-mounted subsystem is similar to a hard disk in function, the hard disk is integrated on a vehicle, and the vehicle ECU reads internal data;
The vehicle-mounted wireless communication module of the intelligent vehicle-mounted subsystem is similar to the functions of an LTE-V vehicle-to-vehicle and road communication scheme communication unit of Datang mobile communication equipment limited company.
The vehicle speed acquisition module, the GPS positioning module, the vehicle speed display module and the voice broadcasting module of the network vehicle-mounted subsystem are similar to the functions of a Cadilac super cryise system.
The vehicle basic information storage module of the network vehicle-mounted subsystem is similar to a hard disk in function, the hard disk is integrated on a vehicle, and the vehicle ECU reads internal data;
the vehicle-mounted wireless communication module of the network-connected vehicle-mounted subsystem is similar to an LTE-V vehicle-mounted communication scheme communication unit of Datang mobile communication equipment limited company in function.
The common vehicle speed shooting and collecting module of the common vehicle-mounted subsystem has similar functions as a Haikang Wipe vision speed-measuring camera;
The position camera acquisition module of the common vehicle-mounted subsystem has similar functions with a vehicle speed feedback instrument radar TBR-510 of the Tuobao technology, and measures the vehicle position and the vehicle speed information;
The license plate camera acquisition module of the common vehicle-mounted subsystem has similar functions to a highway side speed camera of the Haikang vision;
The vehicle-mounted wireless communication module of the common vehicle-mounted subsystem has similar functions to an LTE-V vehicle-to-vehicle and vehicle road communication scheme of Datang mobile communication equipment limited company.
The road side speed decision subsystem functions similarly to the LTE-V car and road communication scheme of large tang mobile communication device limited.
The display screen wired/wireless communication module of the road side display information subsystem is similar to the LTE-V car and road communication scheme communication unit of Datang mobile communication equipment limited company in function.
The guiding information display module of the road side information display subsystem is similar to the gate type variable information board of the Hanwei photoelectric;
The voice broadcasting module of the road side display information subsystem is similar to the voice broadcasting device of Zhejiang Runxin intelligent transportation equipment limited company.
One innovation point of the patent application provides a system for guiding the speed of the heterogeneous traffic flow of the expressway entrance ramp, which realizes the guiding of the expressway entrance ramp vehicles by combining the subsystems so as to achieve the purpose of rapid passing (the aim of accelerating the rapid dredging of the ramp vehicles can be realized without depending on a guiding method); the other innovation point is that a guiding method is introduced on the basis of the system, so that high-precision guiding is realized, and the passing efficiency is effectively improved.
Fig. 1 shows a schematic diagram of the theory of occlusion zones, in which for a fixed occlusion method, the time interval between two vehicles passing through the point of conflict of the confluence zone is a fixed duration, and the length is a safety headway, and the passing interval is independent of the real-time speed and position of the two vehicles. For the mobile blocking method, the time interval of two vehicles passing through the conflict point is variable, the length of the mobile blocking method is related to the relative speed and the relative distance between the two vehicles, and the length of the mobile blocking method is composed of the braking time and the safety margin, so that the utilization efficiency of the passing time can be further improved, but the method has higher requirements on the guiding speed precision of each vehicle and is suitable for vehicles with higher intelligent networking degree. Fig. 3 is a schematic diagram of a scenario of the system for guiding the speed of a heterogeneous traffic flow of an entrance ramp of an expressway in an intelligent networking environment. The scene comprises heterogeneous traffic flows formed by three vehicles, namely an intelligent vehicle, a network-connected vehicle and a common vehicle. The system also comprises a common vehicle information acquisition subsystem for acquiring the common vehicle speed guiding information. And the road side display screen information display subsystem. The method is used for issuing the speed guiding information of the common vehicle. The road side speed decision subsystem is used for receiving all vehicle speed guiding information, arranging the passing sequence, calculating the speed guiding information and sending the speed guiding information. FIG. 3 is a block diagram of a highway entrance ramp heterogeneous traffic flow speed guidance system; the system is divided into five subsystems, namely an intelligent vehicle-mounted subsystem, an internet-connected vehicle-mounted subsystem, a common vehicle information acquisition subsystem, a road side speed decision subsystem and a road side display screen information display subsystem. The intelligent vehicle-mounted subsystem is used for information acquisition, information receiving and vehicle control of the intelligent vehicle. The network-connected vehicle-mounted subsystem is used for information acquisition, information receiving and information reminding of the network-connected vehicle. The common vehicle information acquisition subsystem is used for acquiring and transmitting the speed, the position and the vehicle information of the common vehicle. And the road side speed decision subsystem is used for receiving, arranging the passing sequence and calculating and sending the speed guiding information of all vehicles. And the road side display screen information display subsystem is used for issuing speed guiding information of the common vehicle.
Fig. 4 shows a logic flow chart of a vehicle speed guiding method, which is a method for guiding the heterogeneous traffic flow of the entrance ramp of the expressway in the intelligent networking environment, comprising the following steps:
And S01, when the vehicle reaches the communication range of the road side speed decision-making subsystem, collecting vehicle information and sending the vehicle information to the decision-making subsystem. For intelligent vehicles and internet-enabled vehicles, when the vehicles reach a communication range, the vehicles can package the required speed guiding information into a packet and send the packet to a decision subsystem in a wireless communication mode; for the common vehicle, the license plate, the maximum acceleration, the arrival time, the speed and the position information of the common vehicle are sent to the decision subsystem through cameras of a main road and an entrance ramp in the common vehicle information acquisition subsystem;
And S02, the road side speed decision subsystem receives the transmitted information, distributes the passing road rights of the conflict points of the merging areas according to the 'first-come first-serve' principle, and arranges the passing orders of all vehicles on the main road and the entrance ramp.
And S03, calculating the guiding speed v by using an occlusion interval theory in the high-speed railway by the road side speed decision subsystem. Since the common car and the internet-connected car are still people, the common car and the internet-connected car are calculated by adopting a fixed blocking method. Because the driving main body of the intelligent vehicle is a robot, the speed calculation is performed by adopting a mobile blocking method with higher passing efficiency and higher speed accuracy requirement.
S04, the speed calculation method of the different intelligent level vehicles is as follows:
For the intelligent vehicle, because the intelligent vehicle is controlled by the driving robot, the speed control precision is higher, and therefore, a mobile blocking control method in a blocking interval theory is adopted, the passing time of the front vehicle in the passing sequence is taken as a target point, and the predicted passing time of the vehicle is calculated and remembered according to the position and the speed of the vehicle, so that the guiding speed is obtained by back-pushing.
The whole speed guiding process of the intelligent vehicle comprises five stages of information sending, speed calculating, information receiving, speed adjusting and speed maintaining; because the intelligent vehicle has no driver reaction time, the three stages of information sending, speed calculating and information receiving generally only need about 100ms, so that the time spent in the three stages is ignored. The estimated passing time tpass of the intelligent vehicle is:
Where treach is the time when the vehicle arrives at the communication range of the road side decision system, vi is the guiding speed of the vehicle, v0 is the speed when the vehicle arrives at the communication range, a is the vehicle acceleration, and x is the distance from the vehicle to the point of conflict in the merging region.
According to the mobile occlusion control method, the estimated passing time of the previous vehicle is taken as a target point, and the estimated passing time tpass of the intelligent vehicle is as follows:
Where tpass-f is the expected passing time of the preceding vehicle in the order, tbrake is the shortest braking time of the vehicle, and tsafe is the safety time margin.
The two are combined, and the guiding speed of the vehicle i under the acceleration condition can be obtained:
The guiding speed of the vehicle i in the deceleration condition is:
wherein t isi＝tpass-f+tsafe-treach
For the internet-connected vehicle, the vehicle is controlled by a driver, and the speed control precision is low, so that a fixed blocking control method is adopted, the passing time of the preceding vehicle in sequence is taken as a target point, and the predicted passing time and the guiding speed of the vehicle are obtained through calculation according to a fixed length.
The speed guiding process of the internet-connected vehicle comprises five stages of information sending, speed calculation, driver reaction, speed adjustment and speed maintenance, wherein the two stages of information sending and speed calculation are ignored due to shorter time; the estimated transit time tpass of the internet protocol vehicle is as follows:
where treaction is the time of the driver's reaction to the speed guidance information.
Taking the estimated passing time of the preceding vehicle in sequence as an end point of one end of the section and taking the safety headway as the section length tf of the fixed block, the estimated passing time tpass of the own vehicle is:
tpass＝ti-1+tf
the two are combined, and the guiding speed of the vehicle i under the condition of deceleration can be obtained:
Guiding speed of vehicle i under acceleration:
Wherein t=tpass-f+tf-treach-treaction
For common vehicles, the vehicle is controlled by a driver, and the speed control precision is low, so that a fixed blocking control method is also adopted, and the information of the common vehicle is acquired and sent with delay, so that the calculation method of the section length is different from that of the network-connected vehicle;
The speed guiding process of the common vehicle comprises five stages of information sending, speed calculation, driver reaction, speed adjustment and speed maintenance, wherein the information sending comprises license plate recognition, speed measurement and the like, and generally requires about 500 ms; receiving information includes reading time, typically 1s, from a roadside display screen; the estimated passing time of the common car is as follows:
taking the estimated passing time of the preceding vehicle in the sequence as a target point, and fixing the blocked interval length as a safe headway time and the guiding speed on a driver reading display screen, wherein the estimated passing time of the vehicle is as follows:
tpass＝ti-1+tf+tread
the two are combined, and the guiding speed of the vehicle i under the condition of deceleration can be obtained:
Where the guiding speed of the vehicle i under acceleration:
Wherein t=ti-1+tf-treach-tsafe-treaction
And S05, after the speed calculation is completed, broadcasting guide information to vehicles in a communication range by the speed guide center, automatically driving by the intelligent vehicle, displaying the guide information to a vehicle user, and informing the information to a driver by the internet-connected vehicle through vision and hearing. Meanwhile, the guiding information of the common car is visually and aurally broadcasted through a road side display screen;
it should be understood that the foregoing examples of the present invention are provided merely for clearly illustrating the present invention and are not intended to limit the embodiments of the present invention, and that various other changes and modifications may be made therein by one skilled in the art without departing from the spirit and scope of the present invention as defined by the appended claims.