Method for determining lane changing form special for buses at intersection

Abstract

The invention discloses a method for determining a lane changing form special for buses at an intersection, which belongs to the field of traffic facility design and comprises the following steps of: collecting data, and calculating the maximum queuing length of vehicles at different intersection entrance lanes and a gap between a bus and an adjacent vehicle behind the bus after lane changing; determining the minimum number of times of lane changing of the bus before the intersection, and calculating the total distance required by lane changing of the bus; a random parameter logit bus lane changing risk model utilizing mean value and variance heterogeneity is constructed, the existing intersection bus lane changing risk grade probability is determined, and the form of an intersection bus lane is determined based on the risk grade probability; a random parameter logit bus lane changing risk model using mean value and variance heterogeneity is constructed to provide a scientific basis for optimization of a lane changing form special for buses at an intersection, and the accuracy of decision-making of traffic facilities special for buses is ensured.

Description

Technical Field

[0001] The invention relates to the field of traffic facility design, in particular to a method for determining a bus-only lane change form at an intersection. Background Art

[0002] Most buses change lanes at urban intersections by force, that is, they must change lanes because they need to enter the predetermined entrance lane. At present, the main methods for setting up bus-only lane changes at intersections include no special design, right-hand bus lanes, and intersection bus-only entrance lanes.

[0003] With the increasing congestion of urban traffic and the rapid development of public transportation systems, public transportation, especially buses, as the backbone of urban transportation, plays a vital role in alleviating urban traffic pressure and reducing environmental pollution. However, the urban road environment is complex and changeable, especially during peak hours, buses face many potential safety risks when changing lanes. Buses usually travel on fixed routes. Due to their large size and frequent roadside stops, it is difficult and frequent for vehicles to change lanes, and the braking distance is long. In particular, buses are forced to change lanes multiple times in a short period of time near intersections. Once an emergency occurs, their risk avoidance ability is far less flexible than that of small vehicles, which further increases the risk of buses changing lanes.

[0004] Therefore, special settings need to be made for bus lanes at intersections with heavy traffic pressure, such as setting up right-side bus lanes and intersection bus-only entrance lanes. The present invention aims to provide a method for determining the form of bus-only lane changes at intersections, which is used to improve the safety and efficiency of bus lane changes before intersections and ensure the safety of passengers and pedestrians. Summary of the invention

[0005] In order to improve the safety and efficiency of bus lane changing before intersections, the present invention provides a method for determining the bus lane changing form at intersections. The random parameter logit bus lane changing risk model using mean and variance heterogeneity is constructed to provide a scientific basis for optimizing the bus lane changing form at intersections, thereby ensuring the accuracy of bus-only transportation facility decision-making.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A method for determining a bus-only lane change form at an intersection comprises the following steps:

[0008] (1) Using intersection traffic camera monitoring to collect lane change data of buses at different types of intersections, including vehicle information, traffic environment, and traffic behavior, the maximum queue length of vehicles at the entrance lanes of different intersections was calculated;

[0009] (2) Obtaining the motion information of the bus and the vehicle behind it, and calculating the gap between the bus and the adjacent vehicle behind it after the lane change;

[0010] (3) Based on the location information of the upstream bus stop at the intersection, the location and type of the preceding bus stop, and the bus lane-changing model, determine the turning method of the bus through the intersection, and then determine the minimum number of lane changes required by the bus before the intersection, and calculate the total distance required for the vehicle to change lanes;

[0011] (4) The lane-changing risk level is divided according to the lane-changing gap between buses. A random parameter logit bus lane-changing risk model with heterogeneity of mean and variance is constructed, with the probability of lane-changing risk level as the dependent variable and road width, bus stop form, the minimum number of lane changes required before the intersection, the total distance required for vehicles to change lanes, intersection queue length, and bus length as independent variables.

[0012] (5) Use the mean and variance heterogeneous random parameter logi bus lane change risk model in step (4) to determine the risk level probability of bus lane change at the existing intersection, and determine the form of the bus lane at the intersection based on the risk level probability.

[0013] The vehicle information in the present invention includes vehicle length;

[0014] Traffic environment includes the number of lanes, bus stop format, average vehicle arrival rate, traffic flow, road speed limit, and signal light phase data;

[0015] Traffic behavior includes vehicle location, speed, acceleration, and lane change behavior.

[0016] The maximum queue length of vehicles at the entrance of the intersection in the present invention is calculated as follows:

[0017]

[0018] In the formula, t v ——The starting time difference between adjacent queued vehicles on the entrance lane;

[0019] Q is the average arrival rate of vehicles in one import flow direction at a certain signal phase of a signalized intersection;

[0020] q——the motor vehicle traffic flow in the same direction of the road section per hour;

[0021] r——The effective red light duration of the phase at the signalized intersection;

[0022] ε 1 ——Error term.

[0023] In the present invention, the calculation method of the bus lane-changing gap required for a single forced lane change of the bus in step (2) is as follows:

[0024]

[0025] In the formula, t c is the initial time when the bus changes lanes; T is the end time when the bus changes lanes; S x (0) is t c The initial distance between bus M and its adjacent vehicle M at the moment; a M (t) is the acceleration of bus M; a F (t) is the acceleration of vehicle F; v F (0) is t c The speed of car F at the moment; v M (0) is t c The speed of bus M at time t.

[0026] In the present invention, the total distance required for the vehicle to change lanes in step (3) is:

[0027]

[0028] Among them, K i ——Number of lane changes of the bus (i=1, 2, 3...);

[0029] N j ——The type of bus stop (j=0 is a straight bus stop, j=1 is a bay bus stop).

[0030] In the present invention, the random parameter logit bus lane change risk model with heterogeneity in mean and variance is:

[0031]

[0032] Where P n (m)——the probability that the nth bus lane change causes risk m;

[0033] β mn is the parameter matrix to be estimated for the lane change event; is the density function; is the parameter vector of the probability density function;

[0034] β mn =β m +θ mn Z mn +σ mn exp(w mn W mn )v mn (5)

[0035] In the formula, β m is the average parameter estimation matrix for all lane change events;

[0036] Z mn is the mean heterogeneity matrix affecting the risk level m of bus lane change events;

[0037] θ mn is the corresponding matrix of estimable parameters;

[0038] W mn is the variance heterogeneity matrix affecting the risk level m of the bus lane change event;

[0039] σ mn is the corresponding matrix of estimable parameters;

[0040] v mn is a random matrix with mean 0 and standard deviation 1.

[0041] In the present invention, the lane-changing risk level classification is carried out according to the lane-changing gap of the bus as follows:

[0042] When S x When (t)∈(5,+∞), the risk level is level one;

[0043] When S x When (t)∈(3.5,5], the risk level is level 2;

[0044] When S x When (t)∈(2.5,3.5], the risk level is level 3;

[0045] When S x When (t)∈(1,2], the risk level is level 4;

[0046] When S x When (t)∈(0,1], the risk level is level five.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] (1) The present invention calculates the lane-changing gaps of buses and classifies the lane-changing risk levels according to the lane-changing gaps of buses, thereby constructing a random parameter logit bus lane-changing risk model with the probability of lane-changing risk level as the dependent variable. The model is used to objectively obtain risk data, which can be used to implement dedicated lane-changing methods for buses at intersections, thereby improving the safety and efficiency of bus lane changes before intersections.

[0049] (2) The present invention combines historical traffic monitoring data to explore the relationship between the probability of lane change risk level as the dependent variable and the road width, bus stop form, the minimum number of lane changes required before the intersection, the total distance required for vehicle lane change, the intersection queue length, and the bus length as the independent variables. A random parameter logit bus lane change risk model using mean and variance heterogeneity is constructed to provide a scientific basis for optimizing the bus-only lane change form at intersections, thereby ensuring the accuracy of bus-only transportation facility decision-making. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a schematic diagram of the structure of the present invention. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] like Figure 1 As shown, the present invention provides a method for determining a bus-only lane change form at an intersection, specifically comprising:

[0053] (1) Use intersection traffic camera surveillance to collect lane change data of buses at different types of intersections, including vehicle characteristics (vehicle length, vehicle width), traffic environment (number of lanes, bus stop format, average vehicle arrival rate, traffic flow, road speed limit, and signal light phase data), and traffic behavior (vehicle speed, acceleration, lane change behavior). According to the spatial conditions and traffic conditions of the intersection, calculate the maximum queue length of vehicles at the entrance of different intersections.

[0054] Determine the maximum queue length for each lane of motor vehicles:

[0055]

[0056] In the formula, t v ——The starting time difference between adjacent queued vehicles on the entrance lane (s), take 1s;

[0057] Q——the average arrival rate of vehicles in one import flow direction at a certain signal phase of a signalized intersection (pcu / s);

[0058] q——motor vehicle traffic flow in the same direction of the road section per hour (pcu / h);

[0059] r——The effective red light duration of the phase at the signalized intersection (s);

[0060] ε 1——Error term.

[0061] (2) Obtain the motion information of the bus and the vehicle behind it, and calculate the gap between the bus and the adjacent vehicle behind it after the lane change according to formula (2);

[0062]

[0063] In the formula, t c is the initial time when the bus changes lanes; T is the end time when the bus changes lanes; S x (0) is t c The initial distance between bus M and its adjacent vehicle M at the moment; a M (t) is the acceleration of bus M; a F (t) is the acceleration of vehicle F; v F (0) is t c The speed of car F at the moment; v M (0) is t c The speed of bus M at time t.

[0064] (3) Obtain information about bus routes near the intersection and the location of bus stops upstream of the intersection. Combined with the bus lane-changing model, calculate the turning method of the bus through the intersection based on the station location and station type, and then determine the minimum number of lane changes required by the bus before the intersection, and calculate the total distance required for the vehicle to change lanes.

[0065] The total distance required for the vehicle to change lanes in step (3) is:

[0066]

[0067] Among them, K i ——Number of lane changes of the bus (i=1, 2, 3...);

[0068] N j ——The type of bus stop (j=0 is a straight bus stop, j=1 is a bay bus stop).

[0069] (4) The lane-changing risk levels are divided according to the lane-changing gaps between buses. A random parameter logit bus lane-changing risk model with heterogeneity of mean and variance is constructed with the probability of lane-changing risk level as the dependent variable and road width, bus stop form, the minimum number of lane changes required before the intersection, the total distance required for vehicles to change lanes, intersection queue length, and bus length as independent variables.

[0070] The random parameter logit bus lane change risk model using heterogeneity of mean and variance is constructed as follows:

[0071] Determine the risk level of the bus lane change event, level 1 risk: S x (t)∈(5,+∞); Secondary risk: S x (t)∈(3.5,5]; Three low risks: S x (t)∈(2,3.5]; Level 4 risk: S x (t)∈(1,2]; Level 5 risk: S x (t)∈(0,1].

[0072] The probability of risk m caused by bus lane change is taken as the independent variable, and the independent variable X is set to (x 1 :Road width; x 2 : Bus stop form; x 3 : number of lane changes; x 4 :Bus lane change distance (L Z ); x 5 :Intersection queue length (L 0 ); x 6 :Bus length L M ),

[0073] The lane change risk probability of the random parameter logit model for forced lane change before a bus intersection is defined as:

[0074]

[0075] Where P n (m)——the probability that the nth bus lane change causes risk m;

[0076] β mn ——Parameter matrix to be estimated for lane change event;

[0077] ——Matrix β mn The density function of

[0078] φ – parameter matrix of probability density function (mean and variance).

[0079] The estimated parameter matrix β of the lane change event mn for:

[0080] β mn =β m +θ mn Z mn +σ mn exp(w mn W mn )v mn (5)

[0081] In the formula, β m ——the average parameter estimation matrix of all lane change events;

[0082] Z mn ——It captures the mean heterogeneity matrix that affects the risk level m of the bus lane change event;

[0083] θ mn ——the corresponding matrix of estimable parameters;

[0084] W mn ——The heterogeneity matrix of variance that affects the risk level m of the bus lane change event is captured;

[0085] σ mn ——is the corresponding matrix of estimable parameters;

[0086] v mn ——is a random matrix with mean 0 and standard deviation 1.

[0087] Using NLOGIT6.0 software, the probability density function of the random parameter logit model that affects the lane change gap before the bus intersection is simulated and solved.

[0088] (5) Using the random parameter logit model results of mean and variance heterogeneity obtained in step (4), determine the risk level of bus lane changes at existing intersections, and adjust the form of bus lanes at intersections according to the risk level. The risk level is divided into five levels, with level one having the lowest risk and level five having the highest risk. If the risk level is greater than level three, the form of bus lanes at existing intersections needs to be adjusted to meet safety requirements. If the risk level is equal to or greater than level three, the form of bus lanes at existing intersections can be maintained.

[0089] What is described above is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for determining a bus-only lane change form at an intersection, characterized in that: The following steps are involved: (1) Using intersection traffic camera monitoring to collect lane change data of buses at different types of intersections, including vehicle information, traffic environment, and traffic behavior, the maximum queue length of vehicles at the entrance lanes of different intersections was calculated; (2) Obtaining the motion information of the bus and the vehicle behind it, and calculating the gap between the bus and the adjacent vehicle behind it after the lane change; (3) Based on the location information of the upstream bus stop at the intersection, the location and type of the preceding bus stop, and the bus lane-changing model, determine the turning method of the bus through the intersection, and then determine the minimum number of lane changes required by the bus before the intersection, and calculate the total distance required for the vehicle to change lanes; (4) The lane-changing risk level is divided according to the lane-changing gap between buses. A random parameter logit bus lane-changing risk model with heterogeneity of mean and variance is constructed, with the probability of lane-changing risk level as the dependent variable and road width, bus stop form, the minimum number of lane changes required before the intersection, the total distance required for vehicles to change lanes, intersection queue length, and bus length as independent variables. (5) Use the mean and variance heterogeneous random parameter logi bus lane change risk model in step (4) to determine the risk level probability of bus lane change at the existing intersection, and determine the form of the bus lane at the intersection based on the risk level probability.

2. The method for determining the lane change form of buses at intersections in a city according to claim 1, characterized in that: Vehicle information includes vehicle length; Traffic environment includes the number of lanes, bus stop format, average vehicle arrival rate, traffic flow, road speed limit, and signal light phase data; Traffic behavior includes vehicle location, speed, acceleration, and lane change behavior.

3. The method for determining the lane change form of buses at intersections in a city according to claim 1, characterized in that: The maximum queue length of vehicles on the entrance lane of an intersection is calculated as follows: Where, t v ——The starting time difference between adjacent queued vehicles on the entrance lane; Q is the average arrival rate of vehicles in one import flow direction at a certain signal phase of a signalized intersection; q——the motor vehicle traffic flow in the same direction of the road section per hour; r——The effective red light duration of the phase at the signalized intersection; ε1——error term.

4. The method for determining the lane change form of buses at intersections in a city according to claim 1, characterized in that: The calculation method of the bus lane change gap required for a single forced lane change of the bus in step (2) is as follows: Where, t c is the initial time when the bus changes lanes; T is the end time when the bus changes lanes; S x (0) is t c The initial distance between bus M and its adjacent vehicle M at the moment; a M (t) is the acceleration of bus M; a F (t) is the acceleration of vehicle F; v F (0) is t c The speed of car F at the moment; v M (0) is t c The speed of bus M at time t.

5. The method for determining the lane change form of buses at intersections in a city according to claim 1, characterized in that: The total distance required for the vehicle to change lanes in step (3) is: Among them, K i ——Number of lane changes of the bus (i=1, 2, 3...); N j ——The type of bus stop (j=0 is a straight bus stop, j=1 is a bay bus stop).

6. The method for determining the lane change form of buses at intersections in a city according to claim 1, characterized in that: The random parameter logit bus lane change risk model with heterogeneity in mean and variance is: Where P n (m)——the probability that the nth bus lane change causes risk m; β mn is the parameter matrix to be estimated for the lane change event; is the density function; is the parameter vector of the probability density function; b mn =b m +θ mn Z mn +s mn exp(w mn W mn )v mn (5) In the formula, β m is the average parameter estimation matrix for all lane change events; Z mn is the mean heterogeneity matrix affecting the risk level m of bus lane change events; θ mn is the corresponding matrix of estimable parameters; W mn is the variance heterogeneity matrix affecting the risk level m of the bus lane change event; σ mn is the corresponding matrix of estimable parameters; v mn is a random matrix with mean 0 and standard deviation 1.

7. The method for determining the lane change form of buses at intersections in a city according to claim 1, characterized in that: The lane change risk level classification based on the lane change gap of buses is as follows: When S x When (t)∈(5,+∞), the risk level is level one; When S x When (t)∈(3.5,5], the risk level is level 2; When S x When (t)∈(2.5,3.5], the risk level is level 3; When S x When (t)∈(1,2], the risk level is level 4; When S x When (t)∈(0,1], the risk level is level five.

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