CN104192148B - A kind of major trunk roads speed planing method based on traffic signal information precognition - Google Patents

Abstract

A kind of major trunk roads speed planing method based on traffic signal information precognition, comprises the following steps: step 1) obtain nearest traffic light data；Step 2) obtain the distance with nearest traffic light；Step 3) determine by traffic intersection time range；Step 4) calculation optimization speed；Step 5) judge whether to need by next crossing, if it is, proceed to step 1)；Otherwise, arrive at.

Description

A kind of major trunk roads speed planing method based on traffic signal information precognition

Technical field

The invention belongs to automobile intelligent assist control field, relate to a kind of major trunk roads car based on traffic signal information precognition Speed planing method, controls the most significant for mixed power electric car, pure electric automobile.

Background technology

Oil crisis is always one of major issue of China's economic development faces.The fuel oil consumption reducing automobile can have Effect reduces the consumption of petroleum in Urban Transportation field, has great importance China's energy sustainable development.Orthodox car The acceleration of fuel oil consumption and driver and brake operation course, and dead time is closely related.Automobile is transported on through street During row, can freely travel, electromotor remains a constant speed rotation as far as possible, and fuel economy is preferable.But, automobile is city master When running on arterial highway, can be affected by traffic light, constantly be accelerated, brake, idling operation, the not only combustion of electromotor Oil consumption increases, and there is potential safety hazard.It practice, in order to reduce the automobile fuel oil consumption when major trunk roads travel, automobile Traveling needs to accomplish following three points as far as possible:

1), when being avoided by traffic intersection, quickly accelerate and brake operating；

2) exterior traffic crossing when avoiding red light, the most idle；

3) automobile is controlled within limits by speed during traffic intersection.

Vision and drive reaction distance about 75 meters due to driver, i.e. automobile has traffic light in distance Make acceleration within traffic intersection about 75 meters or brake operating just can affect automobile by the way of traffic intersection.But by Accurately the situation of change of traffic light cannot be predicted in driver, therefore may take when by traffic intersection Quickly accelerate or braking, and be difficult to actively avoid auto idle speed before red light.

Perfect along with the development of Modern wireless communication technology and ground communication equipment, when automobile travels on major trunk roads, Even if automobile and front have the traffic intersection distance of traffic light up to thousands of rice, remain able to obtain this traffic road in real time Mouth signal information accurately.Speed is planned by speed planing method exactly according to signal information, and is supplied to drive Member is as steered reference, thus the method as far as possible controlling the speed of automobile.The method is possible not only to avoid quickly adding of driver Speed and brake operating, and can maximum possible make automobile when green light by traffic intersection, the fuel oil reducing automobile disappears Consumption.But the most domestic, also there is no technology and method that relevant automobile speed plans.

The present invention is directed to automobile when running on major trunk roads the most unobstructed, establish and a kind of believe based on traffic signal The major trunk roads speed planing method of breath.The traffic light information that the method is obtained by wireless telecommunications system, to automobilism Time and acceleration are optimized, and by the speed curves cooked up being supplied to driver as steered reference, thus Make automobile it can be avoided that the quick acceleration and deceleration operation that brings due to signal lights, and idle, reduce automobile in phase To fuel oil consumption when running on unobstructed major trunk roads.

Summary of the invention

Due to current China not to automobile primary arterial highway speed planing method and technology, have influence on vapour to a certain extent Car fuel economy is not enough in order to make up this, it is contemplated that the impact of traffic behavior, the present invention is according to the nearest traffic intersection in front Signal information, automobile speed is carried out planning and calculates, and running time and acceleration are optimized, then by will The speed planned is supplied to driver as steered reference, thus reduces the fuel oil consumption of automobile.

The present invention is achieved through the following technical solutions.A kind of major trunk roads speed planning side based on traffic signal information precognition Method, comprises the following steps:

Step 1): obtain nearest traffic light data.Automobile enters section, first passes through wireless communication system and obtains Traffic intersection signal lamp delta data t recently^s, s ∈ { g, r}.S is signal lights type, and g represents that green light, r represent red light.Signal There are two kinds of situations in lamp change situation, as shown in Figure 1.When running into signal lights and being initially red light, then definition is transformed to green the 1st time The time of lamp isThe time that 2nd time is transformed to red light isThen the time that the 3rd time is transformed to green light isBy that analogy.In like manner, when being initially green light, thenBy that analogy.

Step 2): obtain the distance with nearest traffic light.Automobile enters i-th section, passes through wireless location system Obtain distance D of automobile and the signal lights in i-th section_i。

Step 3): determine by traffic intersection time range.In view of the flow of road, need to reduce automobile as far as possible and pass through The time in section.The automobile shortest time arrives the mode of operation of road cross: first from initial velocity v₀, with acceleration It is worth greatly a_hAccelerate, reach the speed maximum v that road is allowed_limAfter, travel at the uniform speed traffic intersection.

Therefore, the acceleration time t of automobile_aFor:

$t_a=\frac{v_{\lim }-v_0}{a_h}$

With speed v_limThe time of traveling at the uniform speed be:

$t_c=\frac{1}{v_{\lim }}[D_i-v_0\left(\frac{v_{\lim }-v_0}{a_h}\right)-\frac{1}{2}a{\left(\frac{v_{\lim }-v_0}{a_h}\right)}^2]$

The automobile shortest time is t by the time at crossing_t,

t_t=t_a+t_c

Automobile is t by the upper limit of the time interval of traffic intersection i_l, lower limit is t_h, the automobile time by i-th crossing Section is $\left(\begin{array}{cc}{t}_i^l& t_i^h\end{array}\right].$

Be green light during in order to make automobile exterior traffic crossing, when automobile with the shortest time by i-th crossing time, receive When the initial signal of traffic signal information is green light, automobile by the time interval of traffic intersection is:

If $t_{k-1}^g<t_t<t_k^r$

Then $\begin{array}{c}{t}_i^l=t_t\\ t_i^h=t_k^r\end{array}$

If $t_{k+1}^g<t_t<t_k^r$

Then $\begin{array}{c}{t}_i^l=t_k^g\\ t_i^h=t_{k+1}^r\end{array}$

In formula, k is signal change number of times.

Step 4): calculation optimization speed.Consuming performance to improve the fuel oil of automobile, speed planning algorithm needs to protect as far as possible Hold speed constant, reduce unnecessary acceleration or brake operating.The present invention is in the less major trunk roads of vehicle flowrate enterprising driving speed During planning, automobile is used the most once to accelerate or the method for brake operating.The automobile first time of carrying out is t_eAcceleration or Person's brake operating, acceleration is a；Last again with speed v₁At the uniform velocity travel, v₁=v₀+at_e。

In order to ensure the handling capacity of road, it is required that automobile exists $\left(\begin{array}{cc}{t}_i^l& t_i^h\end{array}\right]$ Traffic intersection is passed through in time.It addition, be Improve the fuel economy of automobile, it is required that the speed change minimum of automobile.Therefore, the present invention is with by time and acceleration Degree absolute value sum as optimization aim, majorized function such as following formula:

Min |a|+t

Constraints is:

1) $(v_0{t}_e+\frac{1}{2}{{\mathrm{at}}_e}^2)+(v_0+{\mathrm{at}}_e)(t-t_e)=D_L$

2)0≤t_e≤t

3)t_l≤ t ＜ t_h

4)a_l≤a≤a_h

5)0≤v₀+at_e≤v_lim

In formula, a_lFor acceleration minima, a_hFor acceleration maximum.

Step 5): drive a vehicle according to planning speed by after traffic intersection, according to operator demand, it may be judged whether need to enter Next crossing, forwards step 1 if necessary to)；If it is not required, then end stroke.

Accompanying drawing explanation

Fig. 1 speed planning implementation method schematic diagram；

Fig. 2 test roads figure；

Fig. 3 traffic signal information schematic diagram；

Fig. 4 speed planning curve synoptic diagram；

Fig. 5 major trunk roads speed planning speed curves figure；

Fig. 6 tradition driver's regulation speed curve chart；

Car model figure in Fig. 7 advisor；

Wherein, D in Fig. 3 and Fig. 4_LIt it is the distance between current car position and nearest traffic intersection signal lamp.Automobile exists Current location, obtains two kinds of situations that nearest traffic intersection signal lamp data exist, and upper figure is to run into signal lights to be initially red light, Figure below is initially green light for running into signal lights.

In Fig. 5 and Fig. 6, upper figure is that automobile distance in the process of moving changes over curve, and figure below is that automobile is travelling During speed change over curve.

Detailed description of the invention

It is as follows that the invention will be further described below in conjunction with the accompanying drawings:

Due to current China not to automobile primary arterial highway speed planing method and technology, have influence on automobile to a certain extent Fuel economy, not enough in order to make up this, the present invention has carried out speed planning to the most unobstructed major trunk roads, by wireless biography The signal lights distance of the nearest traffic intersection in transfer device precognition front and information, carry out planning and calculate automobile speed, to when travelling Between and acceleration be optimized, then the speed planned is supplied to driver as steered reference, thus reduces automobile Fuel oil consumes, and detailed process is as shown in Figure 1.

Embodiment 1

Illustrating as a example by root North Street, western imperial city by South Road, Zizhuyuan Park, Beijing, vehicle running route figure is as shown in Figure 2. With South Road, Zizhuyuan Park as starting point, root North Street, western imperial city is terminal.Altogether through ten traffic having traffic light on this road Crossing: Capital Gymnasium South Road, Sanlihe Road, civilian emerging East Street, exhibition road, Che Gongzhuan North Street, Guan Yuanqiao, lane of raising an infant, Zhao step on Yu Lu, street, Xin Jie Kou and root North Street, western imperial city.

Obtain nearest traffic light data.Automobile enters section, first passes through wireless communication system and obtains inbreeding Logical belisha beacon delta data t^s, s ∈ { g, r}.S is signal lights type, and g represents that green light, r represent red light.Signal lights converts There are two kinds of situations in situation, as shown in Figure 3.When running into signal lights and being initially red light, then definition be transformed to for the 1st time green light time Between beThe time that 2nd time is transformed to red light isThen the time that the 3rd time is transformed to green light isWith This analogizes.In like manner, when being initially green light, then $t_1^r<t_2^g<t_3^r,$ By that analogy.

This testing time is 7:00:00 in the morning on April 5th, 2014, and automobile is positioned at starting point (South Road, Zizhuyuan Park), respectively The signal lights conversion moment t of individual traffic intersection^sArray (unit s) is:

Capital Gymnasium South Road: [45,85,185,235,335,375,475,525,625], initial signal lights is r；

Sanlihe Road: [45,90,160,205,275,320,390,435,505], initial signal lights is r；

The emerging East Street of literary composition: [33,89,153,209,273,329,393,449,513], initial signal lights is r；

Exhibition road: [80,140,225,285,370,430,515,575,635], initial signal lights is r；

Che Gongzhuan North Street: [73,146,219,292,365,438,511,584,657], initial signal lights is g；

Official garden bridge: [40,90,245,295,450,500,655,705,860], initial signal lights is r；

Raise an infant lane: [60,140,225,305,390,470,555,635,720], initial signal lights is r；

Zhaodengyu Road: [50,140,215,305,380,470,545,635,710], initial signal lights is r；

Street, Xin Jie Kou: [87,152,252,317,417,482,582,647,747], initial signal lights is r；

Root North Street, western imperial city: [204,284,344,424,484,564,624,704,764], initial signal lights is r；

From test starting point to the end, i.e. from South Road, Zizhuyuan Park to root North Street, western imperial city, the distance of automobile distance traffic intersection Array D of composition_iFor [501,1184,1671,2062,2525,3051,3823,4083,4526,4849], unit m.

Assume that initial speed when automobile starts stroke is 40km/h；The max. speed of road is 50km/h；Adding of automobile Speed is 1.5m/s²；Deceleration is-2m/s²。

Step 1) automobile when the South Road, Zizhuyuan Park, first pass through wireless transmitting system and obtain Capital Gymnasium South Road Traffic light information converting, [45,85,185,235,335,375,475,525,625].Owing to initial signal lights is r；Cause This, $t_1^g=45s,t_2^r=85s,t_3^g=185s,$ The like.

Step 2) simultaneously, automobile passes through wireless location system and road-map, can obtain automobile and Capital Gymnasium south Distance D on road₁, D₁=501m.

Step 3) determine that automobile passes through the time range at Capital Gymnasium South Road.The initial velocity v of automobile₀=40km/h, Accelerate with peak acceleration, a_h=1.5m/s², reach the speed maximum v that road is allowed_limAfter=50km/h, travel at the uniform speed To traffic intersection.

Therefore, the acceleration time t of automobile_aFor:

$t_a=\frac{v_{\lim }-v_0}{a_h}=1.8519s$

With speed v_limThe time of traveling at the uniform speed be:

$t_c=\frac{1}{v_{\lim }}[D_i-v_0\left(\frac{v_{\lim }-v_0}{a_h}\right)-\frac{1}{2}a{\left(\frac{v_{\lim }-v_0}{a_h}\right)}^2]=34.4053s$

The time at automobile shortest time arrival crossing is t_t,

t_t=t_a+t_c=36.2572s

Therefore, definition automobile is t by the upper limit of the time interval of traffic intersection i_l, lower limit is t_h。

Traffic lights information converting according to Capital Gymnasium South Road, automobile is initially accelerated to maximal rate, the evenest It is red light that speed runs to signal lights during traffic intersection, therefore cannot pass through.So that automobile passes through traffic when green light Crossing, the present invention uses nearest green time section as the time range of automobile.Permissible according to traffic light information converting Obtain, this interval be [45 85).

Step 4) calculation optimization speed.Consuming performance to improve the fuel oil of automobile, speed planning algorithm needs to protect as far as possible Hold speed constant, reduce unnecessary acceleration or brake operating.The present invention is in the less major trunk roads of vehicle flowrate enterprising driving speed During planning, automobile is used the most once to accelerate or the method for brake operating.Automobile is first at start time t_s, carry out the time For t_eAcceleration or brake operating, acceleration is a；Last again with speed v₁At the uniform velocity travel, v₁=v₀+at_e.Speed planning curve As shown in Figure 4.

In order to the acceleration making automobile is minimum, and ensure the handling capacity of road, it is required that automobile exists $\left(\begin{array}{cc}{t}_i^l& t_i^h\end{array}\right]$ Time In pass through traffic intersection.The present invention using acceleration absolute value and by time sum as optimization aim, majorized function is as follows Formula:

Min |a|+t

Constraints is:

1) $(v_0{t}_e+\frac{1}{2}{{\mathrm{at}}_e}^2)+(v_0+{\mathrm{at}}_e)(t-t_e)=D_L$

2) 0≤t_e≤t

3) t_l≤ t ＜ t_h

4) a_l≤a≤a_h

5) 0≤v₀+at_e≤v_lim

In formula, a_lFor acceleration minima ,-2m/s², a_hFor acceleration maximum, 1.5m/s²。

By using matlab coding to solve above-mentioned formula, automobile can be obtained from South Road, Zizhuyuan Park to capital physical culture During South Road, shop, optimum speed curves is first with acceleration 0.0016m/s²Running 16.8173s, then travel at the uniform speed arrival Capital Gymnasium South Road.The operation time of whole process is 45s, thus ensures in the way of not parking by Capital Gymnasium south Road.

Step 5) owing to during automobile uniform motion, speed is more than 10km/h, the time is more than 10s, and therefore employing has been planned Speed is run.

Step 6) then, automobile, when Capital Gymnasium South Road, first obtains the traffic light signals letter of Sanlihe Road Breath, be now 7:00:45, the traffic lights information converting of Sanlihe Road become [45,115,160,230,275,345,390, 460], initial signal lights is g.Automobile is D with the distance of the traffic lights of Sanlihe Road₂=1184m-501m=683m.

Step 7) first automobile calculate the shortest by the time, and speed curves be optimized calculating.Discovery automobile needs With deceleration-0.0905m/s²Run slowly 112.0411s, and travel at the uniform speed Sanlihe Road the most again, the operation of whole process Time is 115s.When automobile is by Sanlihe Road, the time is 7:02:40, and continues to travel to civilian emerging East Street.

Step 8) after the same method, garage is crossed all traffic intersections and is arrived at.Automobile passes through the tenth Total operation time of root North Street, Ji Xi imperial city, crossing is 631s.The whole process of automobilism is all without parking.

Contrast with the speed curves without speed planning algorithm, i.e. driver obtains traffic signal according to vision Information is also accelerated or time the distance of deceleration-operation is 75m, speed curves figure as shown in Figure 6: automobile passes through the tenth road Mouthful, total operation time of root North Street, the most western imperial city is 630s.

It is found that the used time of two kinds of speed curves is essentially the same from Fig. 5 and Fig. 6, differ 1s.But use speed rule The speed curves that the method for calculating is set up, can at utmost avoid automobile to stop before red light, decrease the dead time of automobile；And And accelerate more mild with brake operating, thus at utmost reduce the fuel oil consumption of automobile.

Present invention vehicle simulation software based on U.S.'s regenerative resource laboratory advisor, applies orthodox car model Carrying out consuming relative analysis with or without the transport condition under speed planning control and car load fuel oil, car model is as shown in Figure 7.

Table 1 embodiment 1 is calculated fuel oil consumption contrast table

Can obtain from table 1, automobile, according to the speed curves using speed planning algorithm to obtain, is compared and is not used speed The speed curves that planning algorithm obtains travels, and hundred kilometers of fuel oil consumption reduce 14.3%.Therefore, the planning of major trunk roads speed is used to calculate Method can effectively significantly improve the fuel economy of automobile.

Claims (5)

1. a major trunk roads speed planing method based on traffic signal information precognition, comprises the following steps:

Step 1) obtain nearest traffic light data；

Step 2) obtain the distance with nearest traffic light；

Step 3) determine by traffic intersection time range；

Step 4) calculation optimization speed；

Step 5) judge whether to need by next crossing, if it is, proceed to step 1)；Otherwise, arrive at；

Described step 3) in calculated the time t most being short to reach crossing by below equation_t=t_a+t_c；

Wherein t_aFor the acceleration time of automobile, t_cThe time traveled at the uniform speed with the speed maximum allowed for automobile；

$t_a=\frac{v_{\lim }-v_0}{a_h},t_c=\frac{1}{v_{\lim }}\&lsqb;D_i-v_0\left(\frac{v_{\lim }-v_0}{a_h}\right)-\frac{1}{2}a{\left(\frac{v_{\lim }-v_0}{a_h}\right)}^2\&rsqb;;$

Wherein, v_limFor the speed maximum allowed, v₀For initial velocity, a_hFor the maximum of acceleration, D_iFor automobile and i-th The distance of the signal lights in section, α is acceleration.

Method the most according to claim 1, it is characterised in that described step 1) obtain nearest friendship by wireless communication system Ventilating signal lamp data.

Method the most according to claim 1, it is characterised in that described step 2) obtained and inbreeding by wireless location system The distance of ventilating signal lamp.

Method the most according to claim 1, it is characterised in that described step 4) in acceleration absolute value and by the time it With as optimization aim.

Method the most according to claim 1, it is characterised in that described method, based on vehicle simulation software advisor, applies vapour Vehicle model carries out consuming relative analysis with or without the transport condition under speed planning control and car load fuel oil.