A method for considering overtake decision of oncoming vehicle

Abstract

This invention belongs to the field of automotive technology, specifically a method for overtaking decisions considering oncoming vehicles. It includes the following steps: Step 1, determining whether an overtaking intention arises; Step 2, if an overtaking intention arises, determining whether a decision to switch from following the current lane to overtaking can be made; Step 3, if an overtaking decision is made, determining whether it is permissible to overtake by using the oncoming lane based on whether there is interaction with the oncoming vehicle; Step 4, using the result of Step 3 as a state transition condition in driving behavior decision-making; Step 5, generating the vehicle's path and speed based on the vehicle's state in Step 4. This invention considers overtaking safety, traffic efficiency, and the aggressiveness of driving, improving the traffic efficiency of intelligent vehicles.

Description

Technical Field

[0001] This invention belongs to the field of automotive technology, specifically a method for overtaking decisions that take into account oncoming vehicles. Background Technology

[0002] With the continuous development of vehicle-to-everything (V2X) technology, intelligent assisted driving and even intelligent driving technologies have become possible. In many situations, vehicles may need to change lanes to the adjacent oncoming lane to overtake other vehicles, which is called lane-changing overtaking. During this process, there is a possibility of collision with oncoming vehicles in the opposite lane, and there is also a possibility of scraping the vehicle being overtaken.

[0003] Existing overtaking algorithms rarely consider the interaction between oncoming vehicles, but in rural road conditions, overtaking by using other vehicles is unavoidable. Summary of the Invention

[0004] This invention provides an overtaking decision-making method that takes into account oncoming vehicles. This method considers overtaking safety, traffic efficiency, and the aggressiveness of driving, thereby improving the traffic efficiency of intelligent vehicles.

[0005] The technical solution of this invention is described below in conjunction with the accompanying drawings:

[0006] A method for overtaking decisions considering oncoming vehicles includes the following steps:

[0007] Step 1: Determine if there is an intention to overtake;

[0008] Step 2: If an intention to overtake arises, determine whether it is possible to switch from following in the current lane to overtaking;

[0009] Step 3: If an overtaking decision is to be made, determine whether it is permissible to overtake by judging whether there is any interaction with oncoming vehicles;

[0010] Step 4: Use the judgment result of Step 3 as the state transition condition in driving behavior decision-making;

[0011] Step 5: Based on the vehicle's state in Step 4, generate the vehicle's path and speed.

[0012] Furthermore, the specific method for step one is as follows:

[0013] When the vehicle in front of you is traveling at a speed lower than the desired speed or when the obstacle in front is stationary, you need to overtake the vehicle in front by using another vehicle in the same lane. This is the intention to overtake.

[0014] Furthermore, the specific method for step two is as follows:

[0015] The conditions for shifting from following in the same lane to overtaking are:

[0016] D threshold =S F -2·S LC -D safe

[0017] S ego <D threshold &V F <V expect

[0018] Among them, D threshold S is the distance between this vehicle and the vehicle in front, F; F S is the projection of the coordinates of the foreground obstacle onto the road coordinate system; LC =V LC T LC The lane-changing space of a vehicle at its current speed is given by the lane-changing speed V. LC And the time T for lane changing LC The decision; D safe S represents the safe distance between the vehicle in front and the vehicle ahead when the vehicle in front is traveling at zero speed. ego V is the projection of the vehicle coordinate system onto the road coordinate system; F V represents the speed of vehicle F ahead in this lane; expect This is the vehicle's expected speed.

[0019] That is, when the desired speed is greater than the speed of the vehicle in front in the current lane and the distance between the vehicle and the vehicle in front is less than D. threshold At this time, the intention to overtake is generated and the process transitions to the overtaking execution phase.

[0020] Furthermore, the overtaking execution phase includes overtaking execution phase 1: moving from the original lane to the adjacent lane; overtaking execution phase 2: driving along the adjacent lane in the adjacent lane; and overtaking phase 3: returning from the adjacent lane to the original lane.

[0021] Furthermore, the specific method for step three is as follows:

[0022] When there is no interaction with oncoming vehicles;

[0023] When an oncoming vehicle is in the conflict zone, if the oncoming vehicle is at position 1, it cannot complete the overtaking maneuver; its intention to overtake is to yield. Position 1 satisfies the following formula:

[0024] intention = yield, S C1 ∈[S ego S Conflict ]; where S C1 S represents the position of the projection of vehicle C1 onto the road coordinate system; ego S is the projection of this vehicle onto the road coordinate system;Conflict This represents the projection of the conflict area onto the road coordinate system at the current moment;

[0025] When the vehicle is in position 2, the overtaking task can be performed, and the intention of overtaking is not to yield; position 2 satisfies the following formula:

[0026] intention = not yield, S C1 ≤S ego Among them, S C1 S represents the position of the projection of vehicle C1 onto the road coordinate system; ego This is the projection of the vehicle onto the road coordinate system;

[0027] Determine the time when this vehicle and the oncoming vehicle arrive at the conflict zone;

[0028] When the vehicle's current speed V ego ≥Expected speed V for overtaking expect When the vehicle exceeds or reaches the desired speed, the time to reach the conflict zone is calculated using the following formula:

[0029]

[0030] b = V ego -V F

[0031]

[0032] C = S ego -S Conflict

[0033] Among them, S Conflict S is the projection of the conflict area onto the road coordinate system at the current moment; ego V is the projection of this vehicle onto the road coordinate system; expect V is the desired speed for overtaking. F The speed of the vehicles of the road users ahead in this lane; To predict the future time t at time t. acc The projection of the vehicle onto the road coordinate system at time t; acc V is the time required for the vehicle to accelerate from its current speed to the desired overtaking speed. ego The vehicle's current speed; a exp a is the desired acceleration of the vehicle; F For the acceleration of traffic participants ahead;

[0034] When the vehicle's current speed V ego <Expected speed V for overtaking expect When calculating the time it takes for a vehicle to reach the conflict zone, two scenarios need to be considered.

[0035] Scenario 1: The vehicle arrives at the conflict zone C1 before accelerating to the desired overtaking speed; the time it takes for the vehicle to reach the conflict zone is calculated using the following formula:

[0036]

[0037]

[0038]

[0039]

[0040]

[0041] t acc V is the time required for the vehicle to accelerate from its current speed to the desired overtaking speed. expect V is the desired speed for overtaking. ego The vehicle's current speed; To predict the future time t at time t. acc The projection of the conflict area onto the road coordinate system at time S; Conflict V is the projection of the conflict area onto the road coordinate system at the current moment; F The speed of the vehicles of the road users ahead in this lane; a F For the acceleration of traffic participants ahead; To predict the future time t at time t. acc The projection of the vehicle onto the road coordinate system at any given moment;

[0042] The second scenario: After accelerating to the desired speed, the vehicle maintains that speed until it reaches the conflict zone C2; ​​the time it takes for the vehicle to reach the conflict zone is calculated using the following formula:

[0043]

[0044] b = V ego -V F

[0045]

[0046] c = S ego -S Conflict

[0047] If the interaction between the two vehicles occurs when the TTC of the two vehicles = |T ego -T C1 |<TTC Threshold When the time interval is 3 seconds, there is a game theory problem between the two cars; if the time to stop (TTC) of both cars is greater than the time to stop (TTC) of the other car... Threshold= 3s, then the right-of-way is allocated to whoever arrives first; otherwise, if the oncoming traffic arrives at the potential conflict zone in less time than the main vehicle, the main vehicle must yield to the oncoming traffic; otherwise, the main vehicle will decide to overtake, that is, to pass through the potential conflict zone first.

[0048] When interacting with oncoming vehicles;

[0049] When two vehicles engage in a game, this vehicle calculates the aggressiveness of the other vehicles based on their motion states towards the conflict point; the set of actions for this vehicle is: The set of actions of oncoming vehicles is The act of yielding to this vehicle This vehicle failed to yield to the other vehicle. An action to yield to oncoming traffic; This refers to the action of not yielding to oncoming vehicles.

[0050] Furthermore, the specific method for step five is as follows:

[0051] Overtaking execution process:

[0052] The conflict zone is determined by the fact that its movement speed is consistent with the speed of vehicle F; that is, when the vehicle F is moving, the conflict zone is also moving in real time; the location of the conflict zone is calculated using the following formula.

[0053] D csafe =L car +D Fsafe

[0054]

[0055] S Conflict =S F +D csafe

[0056] Among them, D csafe The distance from the conflict zone to the vehicle ahead in this lane; L car The length of this vehicle should allow sufficient space for lane changing; D Fsafe To determine the vehicle's speed V at speed F F Under these conditions, allow sufficient braking distance for vehicle F to react; V F The speed of the vehicles of the road users ahead in this lane; t Delay For driver reaction time during braking and braking system delay; D stop S is the distance between the vehicle and the parent vehicle when the vehicle's speed F is 0; Conflict S is the projection of the conflict area onto the road coordinate system. FThe projection of the vehicle's F direction onto the road coordinate system;

[0057] Overtaking execution phase 1:

[0058] The projection S of this vehicle's road coordinate system ego The final position is determined by transforming the vehicle's position from its Cartesian coordinate system to the Frenet coordinate system, and by setting the lane-changing time to T. LC =3s; The distance required for lane changing is calculated using the following formula;

[0059]

[0060] Among them, D LC V represents the lane-changing space required for this vehicle to change lanes. ego T represents the speed of this vehicle. LC This is the time for changing lanes;

[0061] The Frenet coordinate system is transformed to the Cartesian coordinate system by the following formula, and the global coordinate system at the start and end of the lane change is obtained by solving the global coordinate system.

[0062]

[0063]

[0064] x0 is the x-coordinate of the starting position of the vehicle lane change; y0 is the y-coordinate of the starting position of the vehicle lane change. The heading angle at the starting position of the vehicle lane change; x d y is the x-coordinate of the vehicle's final position after lane change; d The ordinate is the vertical coordinate of the vehicle's final position after lane change; The heading angle is the final position of the vehicle after lane change. The parameters of the cubic polynomial are determined by the coefficients of the cubic polynomial based on its initial and final positions. Since there are four unknowns, four equations can be derived from the initial and final positions to solve for the four unknowns of the cubic polynomial, calculated using the following formula:

[0065] y = a3x 3 +a2x 2 +a1x+a0

[0066]

[0067]

[0068]

[0069] Overtaking execution phase 2:

[0070] During the overtaking execution phase 2, the vehicle was traveling in the adjacent lane when S...ego ≥S Switch Then the overtaking phase of the main vehicle changes from phase 2 to overtaking execution phase 3; S Switch The position where the transition from stage 2 to stage 3 is obtained by the following formula;

[0071]

[0072]

[0073]

[0074] Among them, D Switch This is half the lane-changing space for this vehicle; To address the conflict zone within half the lane-changing time t LC The position reached inside; V F Let a be the speed of vehicle F; F Let F be the acceleration of vehicle F;

[0075] Overtaking execution phase 3:

[0076] The process transitions from overtaking execution phase 2 to overtaking execution phase 3, which generates a lane-changing path from lane 2 to lane 1. The starting position of the lane-changing plan in this phase is determined by the triggering of phase 2. The ending position of the lane-changing plan is determined by the starting position of the lane-changing plan and is calculated using the following formula.

[0077]

[0078]

[0079] Then the trajectory for the second lane change is generated using the following formula;

[0080] y = a3x 3 +a2x 2 +a1x+a0

[0081]

[0082]

[0083]

[0084] If an intention to yield is required during the overtaking phase, the process will transition to returning to the original lane. The method for generating the path to return to the original lane and the path for changing lanes is determined by the following formula.

[0085] y = a3x 3 +a2x 2 +a1x+a0

[0086]

[0087]

[0088]

[0089] The starting and ending points for returning to the original lane are calculated using the following formula.

[0090]

[0091]

[0092] By determining the vehicle's position and current speed, the time to return to the original lane is T. MB The speed of this vehicle is V. ego The distance required to change lanes is D. MB =V ego ·T MB The speed planning method for returning to the original lane is to determine the speed of the vehicle by considering the longitudinal speeds of oncoming vehicles and the vehicle in front, as well as the distance between the vehicle and the two vehicles. The speed is calculated using the following formula.

[0093]

[0094] T E =(S C1 -S e ) / (V WaitMax +V C1 )

[0095] S F +V F T E -S ego =V WaitMax T E +D safe

[0096] Among them, D safe For vehicles in V MBmax At speeds that require maintaining a safe distance from other road users in front in this lane; pd a is the maximum braking deceleration expected by the driver of this vehicle. pdmax t is the maximum braking deceleration of the vehicle in front; Delay Delay time for driver and braking system; D stop S represents the distance between the vehicle and an obstacle in front of it in its lane when the vehicle is stopped. C1 S represents the projected position of an oncoming vehicle in the road coordinate system. ego V represents the projected position of the vehicle in the road coordinate system. C1 T represents the speed of oncoming vehicles. E The time it takes for this vehicle to meet an oncoming vehicle; SF V represents the position of the projection of vehicle F in the road coordinate system. F V is the longitudinal velocity of vehicle F; WaitMax This is the maximum speed planned during the waiting phase;

[0097] If an intention to yield is required during the overtaking phase, the process will transition to returning to the original lane. The method for generating the path to return to the original lane and the path for changing lanes is determined by the following formula.

[0098] y = a3x 3 +a2x 2 +a1x+a0

[0099]

[0100]

[0101]

[0102] The starting and ending points for returning to the original lane are calculated using the following formula;

[0103]

[0104]

[0105] By determining the vehicle's position and current speed, the time to return to the original lane is T. MB The speed of this vehicle is V. ego The distance required to change lanes is D. MB =V ego ·T MB The speed planning method for returning to the original lane is to determine the speed of the vehicle by considering the longitudinal speeds of oncoming vehicles and the vehicle in front, as well as the distance between the vehicle and the two vehicles. The speed is calculated using the following formula.

[0106]

[0107] T E =(S C1 One S eqo ) / (V WaitMax +V C1 )

[0108] S F +V F T E -S ego =V WaitMax T E +D safe

[0109] During the waiting phase, it is also necessary to continuously calculate the changes in the location of the conflict area; if the vehicle's position is greater than S after the overtaking execution phase 1 ends. Switch To determine the location transitioning from Phase 2 to Phase 3, the conflict zone will increase by a distance D along the road coordinate system. changeS The conflict zone is determined by the following formula;

[0110] D changes =S ego +D LC -S Switch

[0111]

[0112] D changes S represents the distance of the change in the conflict zone. ego D is the projection of this vehicle onto the road coordinate system. LC =V ego T LC V represents the space distance for lane changing; ego T is the vehicle's speed. LC The time required for a lane change; S Switch This is the position from overtaking phase 2 to overtaking phase 3;

[0113] The speed gains of this vehicle are as follows:

[0114] When overtaking is not allowed:

[0115] When this vehicle chooses not to overtake, it will continue to travel in the original lane and will enter the waiting phase / return to the original lane phase; the speed planning result of returning to the original lane / waiting phase is used as the speed benefit of choosing not to overtake.

[0116]

[0117] in, The benefit of a given speed, assuming no overtaking, is calculated using the above formula; v wait The speed gain of the vehicle at time t if it switches from the overtaking phase to the return-to-the-original-lane / waiting phase is calculated using the following formula; v traffic This represents the legal speed limit in that traffic scenario;

[0118]

[0119] T E =(S c1 -S ego ) / (V WaitMax +V C1 )

[0120] SF +V F T E -S ego =V WaitMax T E +D safe

[0121] When this vehicle chooses an overtaking strategy

[0122]

[0123] The vehicle speed will reach the vehicle's desired speed; among which, The benefit of a given speed under overtaking conditions is calculated using the above formula; the expected speed v that the overtaking vehicle can reach is... overtake = 20m / s; the legal speed v in traffic scenarios traffic =25m / s;

[0124] Speed ​​gain for oncoming vehicles:

[0125] When yielding to oncoming traffic:

[0126] After this vehicle arrives at the conflict zone, oncoming vehicles arrive at the conflict zone; the speed gain is calculated based on the time it takes for this vehicle to arrive at the conflict zone. The speed that can be obtained when avoiding an oncoming vehicle is obtained by the following formula;

[0127]

[0128]

[0129] When an oncoming vehicle does not yield.

[0130] If the oncoming vehicle does not yield, the speed it will achieve will be Oncoming vehicles will gain a greater speed, therefore the speed gain of oncoming vehicles can be calculated using the following formula;

[0131] The safety benefits of this vehicle are as follows:

[0132] When the intention of this vehicle is to overtake, and the intention of the oncoming vehicle is also to overtake, the benefit of safety is obtained by the following formula;

[0133] TTC=||T ego -T C1 |

[0134]

[0135] Furthermore, the risk and benefit of the vehicle need to be normalized; if the time it takes for the vehicle to reach the conflict zone is longer than the time it takes for the following vehicle to reach the conflict zone, the safety benefit obtained will be lower.

[0136] When the vehicle's intention is to overtake, and the oncoming vehicle's intention is to yield, the safety benefit is 1, which is the maximum value. When the vehicle's intention is to yield, there is no conflict with the oncoming vehicle, so the safety benefit is also 1, as shown by the following formula:

[0137]

[0138] The safety benefits for oncoming vehicles are as follows:

[0139] When the oncoming vehicle intends not to yield, and the vehicle intends to overtake, the safety benefit is calculated using the following formula;

[0140]

[0141] The risk and benefit of vehicles are normalized; when both parties are vying for right of way, the safety benefits of oncoming vehicles are the same as the safety benefits of the vehicle itself.

[0142] When the oncoming vehicle intends to overtake, and the vehicle intends to yield, the safety benefit is 1, which is the maximum value. When the oncoming vehicle intends to yield, there is no conflict with the vehicle, so the safety benefit is also 1, as shown by the following formula:

[0143]

[0144] The payoff matrices for the two vehicles are shown below:

[0145]

[0146] In strategy combination The total benefits of overtaking vehicles and oncoming vehicles are shown below: α1 and β1 represent the weighting parameters of this vehicle between speed and safety factor; α2 and β2 represent the weighting parameters of this vehicle between speed and safety factor; the sum of the two weighting parameters is 1. and This indicates that the two vehicles are in strategy combination S 11 The total revenue is obtained through the following formula:

[0147]

[0148]

[0149] In strategy combination The total revenue of overtaking vehicles and oncoming vehicles is obtained by the following formula;

[0150]

[0151]

[0152] In strategy combination The total revenue of overtaking vehicles and oncoming vehicles is obtained by the following formula;

[0153]

[0154]

[0155] In strategy combination The total revenue of overtaking vehicles and oncoming vehicles is obtained by the following formula;

[0156]

[0157]

[0158] The interaction between the two vehicles is modeled using a dynamic game theory approach, with the other vehicle as the leader and the vehicle itself as the follower. After establishing the dynamic game, the game equilibrium is solved using the following formula.

[0159]

[0160]

[0161] The subscripts L and F represent leaders and followers; s L The strategy representing the leader, s F The strategy of representing followers; This represents the optimal strategy for followers; The optimal strategy representing the leader; S F S represents the strategy space of followers; L The strategic space representing the leader; P represents the optimal set of strategies for followers given the leader's strategy. F Let P be the cost function for the followers. L , where is the cost function of the leader;

[0162] Because drivers interact with different types of traffic participants during driving, it is necessary to calculate the driver's level of aggression. Different types of drivers have different weighting coefficients for safety indicators. Based on the motion state of the interacting vehicles and the positional relationship of the conflict zone, the driving style coefficient of oncoming vehicles is estimated.

[0163] a F t is the acceleration of the vehicle in front in this lane; ego V is the time required for this vehicle to reach the conflict zone. FThis is the speed of the vehicle ahead in this lane; Let t be the projection of the conflict area onto the road coordinate system at time t; Let t be the time t when this vehicle arrives at the conflict zone. ego The location reached by the conflict zone; This is the projection of the position of oncoming vehicles onto the road coordinate system; Let t be the time t when this vehicle arrives at the conflict zone. ego The location reached by oncoming vehicles; For oncoming vehicles at the predicted time t ego The distance to the conflict zone;

[0164]

[0165]

[0166]

[0167] a max Represents the magnitude of acceleration during vehicle acceleration; a min D represents the limit of acceleration when a vehicle decelerates; max D represents the distance between the oncoming vehicle and the conflict zone, given the maximum acceleration of the oncoming vehicle during acceleration. min This refers to the distance between the oncoming vehicle and the conflict zone, given the limit of acceleration during deceleration.

[0168]

[0169]

[0170] when At this time, the oncoming vehicle's current motion is outside the conflict zone; when At this time, the oncoming vehicle has not exceeded the conflict zone under its current motion state; the k coefficient is to adjust the level of aggression according to the current motion range; if D max The larger the proportion within the range of driving ability, the larger k is, indicating that the oncoming vehicle is driving more aggressively.

[0171]

[0172] ρ represents the aggressiveness of the oncoming vehicle. It is modulated by the factor k; the smaller ρ is, the more aggressive the vehicle.

[0173]

[0174] The degree of aggression ρ adjusts the weights of the safety factor β1 and β2; β′1 is the weighting coefficient of the main vehicle after considering the degree of aggression; β′2 is the weighting coefficient of the oncoming vehicle after considering the degree of aggression; ω1 is the magnitude of the influence of the degree of aggression on the weighting coefficient of the main vehicle; ω2 is the magnitude of the influence of the degree of aggression on the weighting coefficient of the oncoming vehicle.

[0175] β′1=β1-ω1p

[0176] β′2=β2+ω2ρ

[0177] To ensure the safety of the game, if an oncoming vehicle still enters the conflict zone even when it is at maximum deceleration, D min If the value is ≤0, the game ends, and the output game result is to yield.

[0178] The beneficial effects of this invention are as follows:

[0179] 1) The overtaking decision algorithm of the present invention can support overtaking vehicles that can be dynamic traffic participants or static traffic participants;

[0180] 2) This invention proposes a model for game theory with oncoming vehicles under overtaking maneuvers; it takes into account safety, traffic efficiency and the degree of driving aggression; and improves the traffic efficiency of intelligent vehicles. Attached Figure Description

[0181] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0182] Figure 1 This is a schematic diagram of the overtaking decision-making framework of the present invention;

[0183] Figure 2 This is a schematic diagram of driving along the route;

[0184] Figure 3 This is a diagram illustrating the triggering of an overtaking intention.

[0185] Figure 4 This is a schematic diagram of the first stage of the overtaking maneuver.

[0186] Figure 5 This is a schematic diagram of the second stage of the overtaking maneuver.

[0187] Figure 6 This is a schematic diagram of the third stage of the overtaking maneuver.

[0188] Figure 7This is a diagram illustrating the vehicle returning to its original lane.

[0189] Figure 8 A diagram illustrating a vehicle waiting to overtake.

[0190] Figure 9 A schematic diagram illustrating the changes in the conflict zone;

[0191] Figure 10 A diagram showing oncoming vehicles within and out of the conflict zone;

[0192] Figure 11 This is a diagram showing the time it takes for this vehicle and an oncoming vehicle to reach the conflict zone;

[0193] Figure 12 A diagram illustrating the game between leaders and followers;

[0194] Figure 13 This is a schematic diagram for estimating the aggressiveness of oncoming vehicles. Detailed Implementation

[0195] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0196] See Figure 1 This invention provides a method for overtaking decisions that takes into account oncoming vehicles, dividing overtaking into the following parts: the driving behavior decision layer includes: lane keeping, overtaking execution module, returning to the original lane, and waiting phase. The decision output includes path and speed.

[0197] 1) Follow the lane: Drive in the lane before overtaking, that is, maintain the current lane;

[0198] 2) Overtaking Execution: This includes three overtaking execution phases: Phase 1: Moving from the original lane to the adjacent lane. Phase 2: Moving along the adjacent lane. Phase 3: Returning to the original lane from the adjacent lane.

[0199] 3) Return to original lane: When overtaking is attempted, if oncoming or following vehicles do not yield, the vehicle returns to its original lane from the adjacent lane. 4) Wait for overtaking: After triggering the overtaking intention, if overtaking conditions are not met, the vehicle waits for overtaking. This invention considers a two-lane scenario where the driving directions of the current lane and the adjacent lane are not the same.

[0200] Specifically as follows:

[0201] Step 1: Determine if there is an intention to overtake;

[0202] The specific method is as follows:

[0203] When the vehicle ahead in this lane is traveling at a speed lower than the desired speed, or when the obstacle ahead is stationary, this vehicle needs to overtake the vehicle ahead by using another lane. The intention to overtake is determined by observing the movement and position of the vehicle F ahead in this lane. Figure 2 As shown.

[0204] Step 2: If an intention to overtake arises, determine whether it is possible to switch from following in the current lane to overtaking;

[0205] The condition for shifting from following in the same lane to overtaking is as follows: That is, when the desired speed is greater than the speed of the vehicle ahead in the same lane and the distance between the vehicle and the vehicle ahead is less than D. threshold At this point, the intention to overtake is generated, and the process transitions to the overtaking execution phase. D threshold This refers to the distance between the vehicle and the vehicle in front (F) when the vehicle transitions from maintaining a straight-ahead position to making an overtaking decision. It is the space reserved to ensure the vehicle can return to its original lane if the overtaking attempt fails.

[0206] The conditions for shifting from following in the same lane to overtaking are:

[0207] D threshold =S F -2·S LC -D safe

[0208] S ego <D threshold &V F <V expect

[0209] Among them, D threshold S is the distance between this vehicle and the vehicle in front, F; F S is the projection of the coordinates of the foreground obstacle onto the road coordinate system; Lc =V LC T LC The lane-changing space of a vehicle at its current speed is given by the lane-changing speed V. LC And the time T for lane changing LC The decision; D safe S represents the safe distance between the vehicle in front and the vehicle ahead when the vehicle in front is traveling at zero speed. ego V is the projection of the vehicle coordinate system onto the road coordinate system; F V represents the speed of vehicle F ahead in this lane; expect This is the vehicle's expected speed.

[0210] That is, when the desired speed is greater than the speed of the vehicle in front in the current lane and the distance between the vehicle and the vehicle in front is less than D. threshold At this time, the intention to overtake is generated and the process transitions to the overtaking execution phase.

[0211] Step 3: If an overtaking decision is to be made, determine whether it is permissible to overtake by judging whether there is any interaction with oncoming vehicles;

[0212] The specific method is as follows:

[0213] When there is no interaction with oncoming vehicles;

[0214] When oncoming vehicles are in the conflict zone, such as Figure 10 As shown. When an oncoming vehicle is in position 1, it cannot complete the overtaking maneuver; the intention to overtake is to yield. Position 1 satisfies the following formula:

[0215] intention = yield, S c1 ∈[S ego S Conflict ]; where S c1 S represents the position of the projection of vehicle C1 onto the road coordinate system; ego S is the projection of this vehicle onto the road coordinate system; Conflict This represents the projection of the conflict area onto the road coordinate system at the current moment;

[0216] When the vehicle is in position 2, the overtaking task can be performed, and the intention of overtaking is not to yield; position 2 satisfies the following formula:

[0217] intention = not yield, S C1 ≤S ego Among them, S C1 S represents the position of the projection of vehicle C1 onto the road coordinate system; ego This is the projection of the vehicle onto the road coordinate system;

[0218] like Figure 11 As shown, due to the conflict zone created by overtaking other traffic participants, there is a yielding and overtaking issue between this vehicle and other traffic participants. The time T for this vehicle to reach the conflict zone... ego The time taken is determined by the vehicle's speed and the distance to the conflict zone. The solution considers three different scenarios. Since the conflict zone changes continuously with the position of the vehicles ahead, and the speed within the conflict zone is the same as the speed of the vehicles ahead (F), calculating the time it takes for the vehicle to reach the conflict zone requires taking into account the motion of the vehicles ahead.

[0219] When the vehicle's current speed V ego ≥Expected speed V for overtaking expectWhen the vehicle exceeds or reaches the desired speed, the time to reach the conflict zone is calculated using the following formula:

[0220]

[0221] b = V ego -V F

[0222]

[0223] c = S ego One S Conflict

[0224] Among them, S Conflict S is the projection of the conflict area onto the road coordinate system at the current moment; ego V is the projection of this vehicle onto the road coordinate system; expect V is the desired speed for overtaking. F The speed of the vehicles of the road users ahead in this lane; To predict the future time t at time t. acc The projection of the vehicle onto the road coordinate system at time t; acc V is the time required for the vehicle to accelerate from its current speed to the desired overtaking speed. ego The vehicle's current speed; a exp a is the desired acceleration of the vehicle; F For the acceleration of traffic participants ahead;

[0225] When the vehicle's current speed V ego <Expected speed V for overtaking epect When calculating the time it takes for a vehicle to reach the conflict zone, two scenarios need to be considered.

[0226] Scenario 1: The vehicle arrives at the conflict zone C1 before accelerating to the desired overtaking speed; the time it takes for the vehicle to reach the conflict zone is calculated using the following formula:

[0227]

[0228]

[0229]

[0230]

[0231]

[0232] t acc V is the time required for the vehicle to accelerate from its current speed to the desired overtaking speed. expect V is the desired speed for overtaking.ego The vehicle's current speed; To predict the future time t at time t. acc The projection of the conflict area onto the road coordinate system at time S; Conflict V is the projection of the conflict area onto the road coordinate system at the current moment; F The speed of the vehicles of the road users ahead in this lane; a F For the acceleration of traffic participants ahead; To predict the future time t at time t. acc The projection of the vehicle onto the road coordinate system at any given moment;

[0233] The second scenario: After accelerating to the desired speed, the vehicle maintains that speed until it reaches the conflict zone C2; ​​the time it takes for the vehicle to reach the conflict zone is calculated using the following formula:

[0234]

[0235] b = V ego -V F

[0236]

[0237] c = S ego -S Conflict

[0238] If the interaction between the two vehicles occurs when the TTC of the two vehicles = |T ego -T C1 |<TTC Threshold When the time interval is 3 seconds, there is a game theory problem between the two cars; if the time to stop (TTC) of both cars is greater than the time to stop (TTC) of the other car... Threshold = 3s, then the right-of-way is allocated to whoever arrives first; otherwise, if the oncoming traffic arrives at the potential conflict zone in less time than the main vehicle, the main vehicle must yield to the oncoming traffic; otherwise, the main vehicle will decide to overtake, that is, to pass through the potential conflict zone first.

[0239] When interacting with oncoming vehicles;

[0240] When two vehicles engage in a game, this vehicle calculates the aggressiveness of the other vehicles based on their motion states towards the conflict point; the set of actions for this vehicle is: The set of actions of oncoming vehicles is The act of yielding to this vehicle This vehicle failed to yield to the other vehicle. An action to yield to oncoming traffic; This refers to the action of not yielding to oncoming vehicles.

[0241] Step 4: Use the judgment result of Step 3 as the state transition condition in driving behavior decision-making;

[0242] Step 5: Based on the vehicle's state in Step 4, generate the vehicle's path and speed.

[0243] The specific method is as follows:

[0244] Overtaking execution process:

[0245] The determination of the conflict zone, and the relationship between the location of the conflict zone and the location of vehicle F, are as follows: Figure 3 As shown; the speed at which the conflict zone moves is the same as the speed of vehicle F; that is, when the vehicle F in front is moving, the conflict zone is also moving in real time; the position of the conflict zone is calculated by the following formula;

[0246] D csafe =L car +D Fsafe

[0247]

[0248] S Conflict =S F +D csafe

[0249] Among them, D csafe The distance from the conflict zone to the vehicle ahead in this lane; L car The length of this vehicle should allow sufficient space for lane changing; D Fsafe To determine the vehicle's speed V at speed F F Under these conditions, allow sufficient braking distance for vehicle F to react; V F The speed of the vehicles of the road users ahead in this lane; t Delay For driver reaction time during braking and braking system delay; D stop S is the distance between the vehicle and the parent vehicle when the vehicle's speed F is 0; Conflict S is the projection of the conflict area onto the road coordinate system. F The projection of the vehicle's F direction onto the road coordinate system;

[0250] Overtaking execution phase 1:

[0251] like Figure 3 The projection S of the road coordinate system of this vehicle ego The final position is determined by transforming the vehicle's position from its Cartesian coordinate system to the Frenet coordinate system, and by setting the lane-changing time to T. LC =3s; The distance required for lane changing is calculated using the following formula;

[0252]

[0253] Among them, D LC V represents the lane-changing space required for this vehicle to change lanes. ego T represents the speed of this vehicle. LC This is the time for changing lanes;

[0254] The Frenet coordinate system is transformed to the Cartesian coordinate system by the following formula, and the global coordinate system at the start and end of the lane change is obtained by solving the global coordinate system.

[0255]

[0256]

[0257] x0 is the x-coordinate of the starting position of the vehicle lane change; y0 is the y-coordinate of the starting position of the vehicle lane change. The heading angle at the starting position of the vehicle lane change; x d y is the x-coordinate of the vehicle's final position after lane change; d The ordinate is the vertical coordinate of the vehicle's final position after lane change; The heading angle is the final position of the vehicle after lane change. The parameters of the cubic polynomial are determined by the coefficients of the cubic polynomial based on its initial and final positions. Since there are four unknowns, four equations can be derived from the initial and final positions to solve for the four unknowns of the cubic polynomial, calculated using the following formula:

[0258] y = a3x 3 +a2x 2 +a1x+a0

[0259]

[0260]

[0261]

[0262] Overtaking execution phase 2:

[0263] See Figure 5 During the overtaking phase 2, the vehicle was traveling in the adjacent lane when S... ego ≥S Switch Then the overtaking phase of the main vehicle changes from phase 2 to overtaking execution phase 3; S Switch The position where the transition from stage 2 to stage 3 is obtained by the following formula;

[0264]

[0265]

[0266]

[0267] Among them, D Switch This is half the lane-changing space for this vehicle; To address the conflict zone within half the lane-changing time t LC The position reached inside; V F Let a be the speed of vehicle F; F Let F be the acceleration of vehicle F;

[0268] Overtaking execution phase 3:

[0269] See Figure 6 The process transitions from overtaking execution phase 2 to overtaking execution phase 3, which generates a lane-changing path from lane 2 to lane 1. The starting position of the lane-changing plan in this phase is determined by the triggering of phase 2. The ending position of the lane-changing plan is determined by the starting position of the lane-changing plan and is calculated using the following formula.

[0270]

[0271]

[0272] Then the trajectory for the second lane change is generated using the following formula;

[0273] y = a3x 3 +a2x 2 +a1x+a0

[0274]

[0275]

[0276]

[0277] If an intention to yield is required during the overtaking phase, the process will transition to returning to the original lane. The method for generating the path to return to the original lane and the path for changing lanes is determined by the following formula.

[0278] y = a3x 3 +a2x 2 +a1x+a0

[0279]

[0280]

[0281]

[0282] The starting and ending points for returning to the original lane are calculated using the following formula.

[0283]

[0284]

[0285] By determining the vehicle's position and current speed, the time to return to the original lane is TM. B The speed of this vehicle is Ve. g o; The distance required for lane changing is DMB = Ve g o×TMB; The speed planning method for returning to the original lane is to determine the speed of the vehicle by considering the longitudinal speeds of oncoming vehicles and the vehicle in front, as well as the distance between the vehicle and the two vehicles. The speed is calculated using the following formula.

[0286]

[0287] TE = (S C1 -S eqo ) / (VW aitMax +VC1)

[0288] SF+VFTE-Se go =VWa itMax TE+Dsa fe

[0289] Among them, D safe For vehicles in VM Bmax At speeds that require maintaining a safe distance from other road users in front in this lane; pd a is the maximum braking deceleration expected by the driver of this vehicle. pd max is the maximum braking deceleration of the vehicle in front; tD elay Delay time for driver and braking system; D stop S represents the distance between the vehicle and an obstacle in front of it in its lane when the vehicle is stopped. C1 S represents the projected position of an oncoming vehicle in the road coordinate system. ego VC1 represents the projected position of this vehicle in the road coordinate system; TE represents the speed of the oncoming vehicle; S represents the time it takes for this vehicle to meet the oncoming vehicle; F Let V be the position of the projection of vehicle F in the road coordinate system; VF is the longitudinal velocity of vehicle F; VW aitMax This is the maximum speed planned during the waiting phase;

[0290] If an intention to yield is required during the overtaking phase, the process will transition to returning to the original lane. The method for generating the path to return to the original lane and the path for changing lanes is determined by the following formula.

[0291] y = a3x 3 +a2x 2 +a1 x+a0

[0292]

[0293]

[0294]

[0295] The starting and ending points for returning to the original lane are calculated using the following formula;

[0296]

[0297]

[0298] By determining the vehicle's position and current speed, the time to return to the original lane is TM. B The speed of this vehicle is Ve. g o; The distance required for lane changing is DMB = Ve g o…TMB, such as Figure 7 As shown; the speed planning method for returning to the original lane is to determine the speed of the vehicle by the longitudinal speed of the oncoming vehicle and the vehicle in front, as well as the distance between the vehicle and the two vehicles, and is obtained by the following formula;

[0299]

[0300] TE = (S C1 One S eqo ) / (VW aitMax +VC1)

[0301] SF+VFTE-Se go =VWa itMax TE+Dsa fe

[0302] like Figure 8 As shown, the system continuously assesses the collision risk in the lane while waiting to overtake. If the overtaking attempt is suspected of being a preemptive move, then the overtaking maneuver proceeds. If the attempt is suspected of being a swerve, the system continues to wait. The overtaking waiting phase places greater emphasis on speed planning.

[0303] Speed ​​planning during the waiting phase is determined based on the speed of the vehicle in front, the speed of oncoming vehicles, and the space between the vehicle and both vehicles. This paper's speed planning determines the maximum expected speed for the vehicle during the overtaking waiting phase under current conditions. During the waiting phase, the vehicle continuously plans its optimal speed while in motion. The planning period is ΔD. p lan = V = e g ot p lan. t p lan represents the planning time period.

[0304] D safe For vehicles in VM Bmax At speeds, a safe distance must be maintained from other road users in front in this lane. pdThis is the maximum braking deceleration expected by the driver of this vehicle. pd `max` represents the maximum braking deceleration of the vehicle in front. `tD` elay Delay time for the driver and braking system. (D) stop S represents the distance between the vehicle and an obstacle in front of it in this lane when the vehicle has stopped. C1 S represents the projected position of an oncoming vehicle in the road coordinate system. ego This represents the projected position of the vehicle in the road coordinate system. VC1 is the speed of the oncoming vehicle. TE is the time it takes for the vehicle to meet the oncoming vehicle. S F VF represents the projected position of vehicle F in the road coordinate system. VF represents the longitudinal velocity of vehicle F. VW aitMax This is the maximum speed planned during the waiting phase.

[0305]

[0306] TE = (SC1 - Se) g o) / (VWaitMax+VC1)

[0307] SF+VFTE-Se g o=VWaitMaxTE+Dsa f e

[0308] During the waiting phase, it is also necessary to continuously calculate the changes in the location of the conflict zone. For example... Figure 9 As shown, if the position of this vehicle is greater than SS after the overtaking execution phase 1 is completed... witch To determine the location transitioning from Phase 2 to Phase 3, the conflict zone will increase by a distance D along the road coordinate system. changeS The conflict zone is determined by the following formula: D changeS S represents the distance at which the conflict zone changes. ego D is the projection of this vehicle onto the road coordinate system. LC =V ego T LC V represents the spatial distance for lane changing. ego This is the vehicle's speed. (T) Lc The time required for a lane change. (S) Switch This is the position from overtaking phase 2 to overtaking phase 3.

[0309] D changes =S ego +D LC -S Switch

[0310]

[0311] The benefits of this vehicle include speed benefits and safety benefits;

[0312] Speed ​​gain of this vehicle:

[0313] When overtaking is not allowed:

[0314] When this vehicle chooses not to overtake, it will continue to travel in its original lane and enter a waiting / returning to the original lane phase. The speed planning result for returning to the original lane / waiting phase is used as the speed gain for choosing not to overtake.

[0315]

[0316] in The benefit of a given speed, assuming no overtaking, is calculated using the above formula. wait The speed gain of the vehicle at time t if it switches from the overtaking phase to the return-to-the-original-lane / waiting phase is calculated using the following formula. traffic This represents the legal speed limit in that traffic scenario.

[0317]

[0318] T E =(S C1 -S ego ) / (V WaitMax +V C1 )

[0319] S F +V F T E -S ego =V WaitMax T E +D safe

[0320] When this vehicle chooses an overtaking strategy

[0321]

[0322] The vehicle speed will reach the vehicle's desired speed. Among them... The benefit of a given speed under overtaking conditions is calculated using the above formula. The expected speed v that the overtaking vehicle can reach is... goer t ake =20m / s. The legal speed in this traffic scenario, vtraffic, is 25m / s.

[0323] Speed ​​gain for oncoming vehicles:

[0324] When yielding to oncoming traffic:

[0325] After this vehicle arrives at the conflict zone, oncoming vehicles also arrive at the conflict zone. Therefore, it is necessary to calculate the speed gain based on the time it takes for this vehicle to arrive at the conflict zone. The speed that can be obtained when avoiding an oncoming vehicle is obtained by the following formula.

[0326]

[0327]

[0328] When an oncoming vehicle does not yield;

[0329] If the oncoming vehicle does not yield, the speed it will achieve will be Oncoming vehicles will gain a greater speed, therefore the speed gain of oncoming vehicles can be calculated using the following formula.

[0330]

[0331] The safety benefits of this vehicle are as follows:

[0332] When the intention of this vehicle is to overtake, and the intention of the oncoming vehicle is also to overtake, the benefit of safety is obtained by the following formula;

[0333] TTC = | L g o-TC1|

[0334]

[0335] Furthermore, the risk and benefit of the vehicle need to be normalized; if the time it takes for the vehicle to reach the conflict zone is longer than the time it takes for the following vehicle to reach the conflict zone, the safety benefit obtained will be lower.

[0336] When the vehicle's intention is to overtake, and the oncoming vehicle's intention is to yield, the safety benefit is 1, which is the maximum value. When the vehicle's intention is to yield, there is no conflict with the oncoming vehicle, so the safety benefit is also 1, as shown by the following formula:

[0337]

[0338] The safety benefits for oncoming vehicles are as follows:

[0339] When the oncoming vehicle intends not to yield, and the vehicle intends to overtake, the safety benefit is calculated using the following formula;

[0340]

[0341] The risk and benefit of vehicles are normalized; when both parties are vying for right of way, the safety benefits of oncoming vehicles are the same as the safety benefits of the vehicle itself.

[0342] When the oncoming vehicle intends to overtake, and the vehicle intends to yield, the safety benefit is 1, which is the maximum value. When the oncoming vehicle intends to yield, there is no conflict with the vehicle, so the safety benefit is also 1, as shown by the following formula:

[0343]

[0344] The payoff matrices for the two vehicles are shown below:

[0345]

[0346] In strategy combination The total benefits of overtaking vehicles and oncoming vehicles are shown below: α1 and β1 represent the weighting parameters of this vehicle between speed and safety factor; α2 and β2 represent the weighting parameters of this vehicle between speed and safety factor; the sum of the two weighting parameters is 1. and This indicates that the two vehicles are in strategy combination S 11 The total revenue is obtained through the following formula:

[0347]

[0348]

[0349] In strategy combination The total revenue of overtaking vehicles and oncoming vehicles is obtained by the following formula;

[0350]

[0351]

[0352] In strategy combination The total revenue of overtaking vehicles and oncoming vehicles is obtained by the following formula;

[0353]

[0354]

[0355] In strategy combination The total revenue of overtaking vehicles and oncoming vehicles is obtained by the following formula;

[0356]

[0357]

[0358] The interaction between the two vehicles is modeled using a dynamic game theory approach, with the other vehicle as the leader and the vehicle itself as the follower. After establishing the dynamic game, the game equilibrium is solved using the following formula.

[0359]

[0360]

[0361] The subscripts L and F represent leaders and followers; S L The strategy representing the leader, s F The strategy of representing followers; This represents the optimal strategy for followers; SF represents the leader's optimal strategy; SL represents the follower's strategy space; This represents the set of optimal strategies for followers given the leader's strategy. PF is the follower's cost function, and PL is the leader's cost function, such as... Figure 12 As shown.

[0362] Because drivers interact with different types of traffic participants during driving, it is necessary to calculate the driver's level of aggression. Different types of drivers have different weighting coefficients for safety indicators. Based on the motion state of the interacting vehicles and the positional relationship of the conflict zone, the driving style coefficient of oncoming vehicles is estimated.

[0363] a F t is the acceleration of the vehicle in front in this lane; ego VF is the time required for this vehicle to reach the conflict area; VF is the speed of the vehicle ahead in this lane. Let t be the projection of the conflict area onto the road coordinate system at time t; The time tego is the time when this vehicle arrives at the conflict zone, and the location of the conflict zone reached; This is the projection of the position of oncoming vehicles onto the road coordinate system; For the time when this vehicle arrives at the conflict zone, tego represents the position reached by the oncoming vehicle; The distance between an oncoming vehicle and the conflict zone after the predicted time tego;

[0364]

[0365]

[0366]

[0367] a max Represents the magnitude of acceleration during vehicle acceleration; a min D represents the limit of acceleration when a vehicle decelerates; max D represents the distance between the oncoming vehicle and the conflict zone, given the maximum acceleration of the oncoming vehicle during acceleration. min This refers to the distance between the oncoming vehicle and the conflict zone, given the limit of acceleration during deceleration.

[0368]

[0369]

[0370] when At this time, the oncoming vehicle's current motion is outside the conflict zone; when At this time, the oncoming vehicle has not exceeded the conflict zone under its current motion state; the k coefficient is to adjust the level of aggression according to the current motion range; if D max The larger the proportion within the range of driving ability, the larger k is, indicating that the oncoming vehicle is driving more aggressively.

[0371]

[0372] ρ represents the aggressiveness of the oncoming vehicle. It is modulated by the factor k; the smaller ρ is, the more aggressive the vehicle.

[0373]

[0374] The degree of aggression ρ adjusts the weights of the safety factor β1 and β2; β′1 is the weighting coefficient of the main vehicle after considering the degree of aggression; β′2 is the weighting coefficient of the oncoming vehicle after considering the degree of aggression; ω1 is the magnitude of the influence of the degree of aggression on the weighting coefficient of the main vehicle; ω2 is the magnitude of the influence of the degree of aggression on the weighting coefficient of the oncoming vehicle.

[0375] β′1=β1-ω1ρ

[0376] β′2=β2+ω2p

[0377] To ensure the safety of the game, if an oncoming vehicle still enters the conflict zone even when it is at maximum deceleration, D min If the value is ≤0, the game ends, and the output game result is to yield.

[0378] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method of considering overtake decision for oncoming vehicles, characterized in that, Includes the following steps: Step 1: Determine if there is an intention to overtake; Step 2: If an overtaking intention arises, determine whether it is possible to switch from following in the current lane to overtaking. The specific method is as follows: The conditions for shifting from following in the same lane to overtaking are: ； ； in, This is the distance between this vehicle and the vehicle in front, F; The projection of the coordinates of the foreground obstacle onto the road coordinate system; The lane-changing space of a vehicle at its current speed is determined by the speed at which it changes lanes. and the time for changing lanes The decision; This refers to the safe distance between the vehicle in front and the vehicle ahead when the vehicle in front is traveling at zero speed. This is the projection of the vehicle's coordinate system onto the road coordinate system; The speed of vehicle F ahead in this lane; This is the vehicle's expected speed. That is, when the desired speed is greater than the speed of the vehicle in front in the current lane and the distance between the current vehicle and the vehicle in front is less than... At that time, the intention to overtake is generated and the process transitions to the overtaking execution phase; Step 3: If an overtaking decision is to be made, determine whether it is permissible to overtake by judging whether there is any interaction with oncoming vehicles; Step 4: Use the judgment result of Step 3 as the state transition condition in driving behavior decision-making; Step 5: Based on the vehicle's state in Step 4, generate the vehicle's path and speed.

2. The overtaking decision-making method considering oncoming vehicles according to claim 1, characterized in that, The specific method for step one is as follows: When the vehicle in front of you is traveling at a speed lower than the desired speed or when the obstacle in front is stationary, you need to overtake the vehicle in front by using another vehicle in the same lane. This is the intention to overtake.

3. The method of claim 1, wherein, The overtaking execution phase includes overtaking execution phase 1: moving from the original lane to the adjacent lane; overtaking execution phase 2: driving along the adjacent lane in the adjacent lane; and overtaking phase 3: returning from the adjacent lane to the original lane.

4. The method of claim 3, wherein, The specific method for step three is as follows: When there is no interaction with oncoming vehicles; When an oncoming vehicle is in the conflict zone, if the oncoming vehicle is at position 1, it cannot complete the overtaking maneuver; its intention to overtake is to yield. Position 1 satisfies the following formula: ;in, The position of the vehicle C1 projected onto the road coordinate system; This is the projection of the vehicle onto the road coordinate system; This represents the projection of the conflict area onto the road coordinate system at the current moment; When the vehicle is in position 2, the overtaking task can be performed, and the intention of overtaking is not to yield; position 2 satisfies the following formula: ;in, The position of the vehicle C1 projected onto the road coordinate system; This is the projection of the vehicle onto the road coordinate system; Determine the time when this vehicle and the oncoming vehicle arrive at the conflict zone; when When the vehicle exceeds or reaches the desired speed, the time to reach the conflict zone is calculated using the following formula: ； ； ； ； in, This represents the projection of the conflict area onto the road coordinate system at the current moment; This is the projection of the vehicle onto the road coordinate system; ; The speed of the vehicles of the road users ahead in this lane; In order to be in At present, predicting the future The projection of the vehicle onto the road coordinate system at any given moment; The time required for the vehicle to accelerate from its current speed to the desired overtaking speed; This represents the vehicle's current speed. The desired acceleration of the vehicle; For the acceleration of traffic participants ahead; When The time calculation for the vehicle to travel to the conflict area needs to be divided into two cases; Scenario 1: The vehicle arrives at the conflict zone before accelerating to the desired overtaking speed. The time it takes for a vehicle to reach the conflict zone is calculated using the following formula: ； ； ； ； ； The time required for the vehicle to accelerate from its current speed to the desired overtaking speed; ; This represents the vehicle's current speed. exist At present, predicting the future The projection of the conflict area onto the road coordinate system at any given moment; This represents the projection of the conflict area onto the road coordinate system at the current moment; The speed of the vehicles of the road users ahead in this lane; For the acceleration of traffic participants ahead; In order to be in At present, predicting the future The projection of the vehicle onto the road coordinate system at any given moment; The second scenario: After accelerating to the desired speed, the vehicle maintains that speed until it reaches the conflict zone. The time it takes for a vehicle to reach the conflict zone is calculated using the following formula: ； ； ； ； If the interaction between the two vehicles occurs between the two vehicles... In the case of [a situation where], there is a game theory problem between the two cars; if the two cars [are in a certain situation], then there is a game theory problem between the two cars. If the oncoming traffic arrives at the potential conflict zone in less time than the main vehicle arrives at the potential conflict zone, the main vehicle must give way to the oncoming traffic; otherwise, the main vehicle will decide to overtake, i.e., have priority to pass through the potential conflict zone. When interacting with oncoming vehicles; When two vehicles engage in a game, this vehicle calculates the aggressiveness of the vehicles based on their motion states towards the conflict point; the set of actions for this vehicle is: The set of actions of oncoming vehicles is . The act of yielding to this vehicle This vehicle failed to yield to the other vehicle. An action to yield to oncoming traffic; This refers to the action of not yielding to oncoming vehicles.

5. The method of claim 4, wherein, The specific method for step five is as follows: Overtaking execution process: The conflict zone is determined by the fact that its movement speed is consistent with the speed of vehicle F; that is, when the vehicle F is moving, the conflict zone is also moving in real time; the location of the conflict zone is calculated using the following formula. ； ； ； in, The distance between the conflict zone and the vehicle ahead in this lane; The length of this vehicle should allow sufficient space for lane changing; In order to determine the vehicle speed Under these conditions, give the vehicle Leave sufficient braking distance to react; The speed of the vehicles of the road users ahead in this lane; For driver reaction time during braking and braking system delay; For the vehicle Distance to this vehicle when the speed is 0; The projection of the conflict area onto the road coordinate system; For vehicles Projection to the road coordinate system; Overtaking execution phase 1: Projection of this vehicle's road coordinate system The final position is determined by transforming the vehicle's position from its Cartesian coordinate system to the Frenet coordinate system, and by setting the lane-changing time as... The distance required for lane changing is calculated using the following formula; ； in, This refers to the amount of space required for this vehicle to change lanes. This refers to the speed of the vehicle. This refers to the time spent changing lanes; The Frenet coordinate system is transformed to the Cartesian coordinate system by the following formula, and the global coordinate system at the start and end of the lane change is obtained by solving the global coordinate system. ； ； The x-coordinate represents the starting position of the vehicle lane change; The ordinate is the starting position of the vehicle changing lanes. The heading angle at the starting position of the vehicle lane change; The x-coordinate of the vehicle's final position after lane change; The ordinate is the vertical coordinate of the vehicle's final position after lane change; The heading angle is the final position of the vehicle after lane change. The parameters of the cubic polynomial are determined by the coefficients of the cubic polynomial based on its initial and final positions. Since there are four unknowns, four equations can be derived from the initial and final positions to solve for the four unknowns of the cubic polynomial, calculated using the following formula: ； ； ； ； Overtaking execution phase 2: During the overtaking phase 2, the vehicle was traveling in the adjacent lane when... Then the overtaking phase of the main vehicle changes from phase 2 to overtaking execution phase 3; The position where the transition from stage 2 to stage 3 is obtained by the following formula; ； ； ； in, This is half the lane-changing space for this vehicle; To allow for half the lane change time in the conflict zone The location reached within; Let F be the speed of vehicle F; Let F be the acceleration of vehicle F; Overtaking execution phase 3: The process transitions from overtaking execution phase 2 to overtaking execution phase 3, which generates a lane-changing path from lane 2 to lane 1. The starting position of the lane-changing plan in this phase is determined by the triggering of phase 2. The ending position of the lane-changing plan is determined by the starting position of the lane-changing plan and is calculated using the following formula. ； ； Then the trajectory for the second lane change is generated using the following formula; ； ； ； ； If an intention to yield is required during the overtaking phase, the process will transition to returning to the original lane. The method for generating the path to return to the original lane and the path for changing lanes is determined by the following formula. ； ； ； ； The starting and ending points for returning to the original lane are calculated using the following formula; ； ； By determining the vehicle's position and current speed, the time required to return to the original lane is... The speed of this vehicle is The distance required to change lanes is The speed planning method for returning to the original lane is to determine the speed of the vehicle by considering the longitudinal speeds of oncoming vehicles and the vehicle in front, as well as the distance between the vehicle and the two vehicles. The speed is calculated using the following formula. ； ； ； in, For vehicles in At speeds, a safe distance must be maintained from other road users in front of you in this lane; This is the maximum braking deceleration expected by the driver of this vehicle. The maximum braking deceleration of the vehicle in front; Delay time for the driver and braking system; This refers to the distance between the vehicle and an obstacle in front of it in the same lane when the vehicle is stopped. This represents the projected position of an oncoming vehicle in the road coordinate system. This represents the position of the vehicle's projection in the road coordinate system; The speed of oncoming vehicles; The time when this vehicle meets an oncoming vehicle; Let F be the position of the projection of vehicle F in the road coordinate system; Let F be the longitudinal velocity of vehicle F; This is the maximum speed planned during the waiting phase. If an intention to yield is required during the overtaking phase, the process will transition to returning to the original lane. The method for generating the path to return to the original lane and the path for changing lanes is determined by the following formula. ； ； ； ； The starting and ending points for returning to the original lane are calculated using the following formula; ； ； By determining the vehicle's position and current speed, the time required to return to the original lane is... The speed of this vehicle is The distance required to change lanes is The speed planning method for returning to the original lane is to determine the speed of the vehicle by considering the longitudinal speeds of oncoming vehicles and the vehicle in front, as well as the distance between the vehicle and the two vehicles. The speed is calculated using the following formula. ； ； ； During the waiting phase, it is also necessary to continuously calculate the changes in the location of the conflict zone; if the vehicle's position is greater than [a certain value] after the overtaking execution phase 1 ends. To determine the transition from Phase 2 to Phase 3, the conflict zone will increase in distance along the road coordinate system. The conflict zone is determined by the following formula; ； ； in, The distance of the conflict zone changes; This is the projection of the vehicle onto the road coordinate system; The space distance for changing lanes; This is the vehicle's speed; The time required for lane changing; This is the position from overtaking phase 2 to overtaking phase 3; The speed gains of this vehicle are as follows: When overtaking is not allowed: When this vehicle chooses not to overtake, it will continue to travel in the original lane and will enter the waiting phase / return to the original lane phase; the speed planning result of returning to the original lane / waiting phase is used as the speed benefit of choosing not to overtake. ； in, The benefit of a given speed under the condition of not overtaking is calculated using the above formula; In order to be in The speed gain of the vehicle if it switches from the overtaking phase to the return to the original lane / waiting phase is calculated using the following formula; Represents the legal speed limit in traffic scenarios; ； ； ； When this vehicle chooses an overtaking strategy: ； The vehicle speed will reach the vehicle's desired speed; among which, The benefit of a given speed under overtaking conditions is calculated using the above formula; the expected speed that the overtaking vehicle can achieve. Regulations on speed in traffic scenarios ; Speed ​​gain for oncoming vehicles: When yielding to oncoming traffic: After this vehicle arrives at the conflict zone, oncoming vehicles arrive at the conflict zone; the speed gain is calculated based on the time it takes for this vehicle to arrive at the conflict zone. The speed that can be obtained when avoiding an oncoming vehicle is obtained by the following formula; ； ； When an oncoming vehicle fails to yield: If the oncoming vehicle does not yield, the speed it will achieve will be Oncoming vehicles will gain a greater speed; therefore, the speed gain for oncoming vehicles can be calculated using the following formula: ； The safety benefits of this vehicle are as follows: When the intention of this vehicle is to overtake, and the intention of the oncoming vehicle is also to overtake, the benefit of safety is obtained by the following formula; ； ； Furthermore, the risk and benefit of the vehicle need to be normalized; if the time it takes for the vehicle to reach the conflict zone is longer than the time it takes for the following vehicle to reach the conflict zone, the safety benefit obtained will be lower. When the vehicle's intention is to overtake, and the oncoming vehicle's intention is to yield, the safety benefit is 1, which is the maximum value. When the vehicle's intention is to yield, there is no conflict with the oncoming vehicle, so the safety benefit is also 1, as shown by the following formula: ； The safety benefits for oncoming vehicles are as follows: When the oncoming vehicle intends not to yield, and the vehicle intends to overtake, the safety benefit is calculated using the following formula; ； The risk and benefit of vehicles are normalized; when both parties are vying for right of way, the safety benefits of oncoming vehicles are the same as the safety benefits of the vehicle itself. When the oncoming vehicle intends to overtake, and the vehicle intends to yield, the safety benefit is 1, which is the maximum value. When the oncoming vehicle intends to yield, there is no conflict with the vehicle, so the safety benefit is also 1, as shown by the following formula: ； The payoff matrices for the two vehicles are shown below: ； In strategy combination The total benefits for overtaking vehicles and oncoming vehicles are shown below: , This parameter represents the weighting of the vehicle's speed and safety factor. , This represents the weighting parameter between the vehicle's speed and safety factor; the sum of the two weighting parameters is 1. and This indicates the two vehicles in the strategy combination. The total revenue is obtained through the following formula: ； ； In strategy combination The total revenue of overtaking vehicles and oncoming vehicles is obtained by the following formula; ； ； In strategy combination The total revenue of overtaking vehicles and oncoming vehicles is obtained by the following formula; ; ； In the strategy combination The total benefit of the overtaking vehicle and the oncoming vehicle is obtained by the following equation; ； ； The interaction between the two vehicles is modeled using a dynamic game theory approach, with the other vehicle as the leader and the vehicle itself as the follower. After establishing the dynamic game, the game equilibrium is solved using the following formula. ； ； Subscript and Representing leaders and followers; Strategies representing leaders The strategy of representing followers; This represents the optimal strategy for followers; The optimal strategy representing the leader; The strategy space representing followers; The strategic space representing the leader; This represents the optimal set of strategies for followers given the leader's strategy. For the cost function of the followers, The cost function for the leader; Because drivers interact with different types of traffic participants during driving, it is necessary to calculate the driver's level of aggression. Different types of drivers have different weighting coefficients for safety indicators. Based on the motion state of the interacting vehicles and the positional relationship of the conflict zone, the driving style coefficient of oncoming vehicles is estimated. This is the acceleration of the vehicle in front in this lane; This is the time required for this vehicle to reach the conflict zone; This is the speed of the vehicle ahead in this lane; for The projection of the conflict area onto the road coordinate system at any given moment; The time it takes for this vehicle to reach the conflict zone The location reached by the conflict zone; This is the projection of the position of oncoming vehicles onto the road coordinate system; The time it takes for this vehicle to reach the conflict zone The location reached by oncoming vehicles; For oncoming vehicles at the predicted time The distance to the conflict zone; ； ； ； Represents the magnitude of acceleration during vehicle acceleration; It represents the limit of acceleration when a vehicle decelerates; This refers to the distance between the oncoming vehicle and the conflict zone, given the maximum acceleration of the oncoming vehicle during acceleration. This refers to the distance between the oncoming vehicle and the conflict zone, given the limit of acceleration during deceleration. ； ； when At this time, the oncoming vehicle's current motion is outside the conflict zone; when At this time, the oncoming vehicle has not crossed the conflict zone in its current state of motion; The coefficient is used to adjust the level of aggression based on the current range of motion; if The larger the proportion within the range of athletic ability, the better. The larger the value, the more aggressive the driving of oncoming vehicles. ； Due to the aggressiveness of oncoming vehicles, Adjust the degree of radicalism of the factors; The smaller the value, the more aggressive the vehicle. ； Radicality The proportion of the safety factor , Adjustments were made; The weighting coefficient after considering the aggressiveness of the main vehicle; Weighting coefficients for oncoming vehicles after considering the degree of aggression; The degree of aggression affects the weighting coefficient of this vehicle; The degree of aggression affects the weighting coefficient of oncoming vehicles; ； ； To ensure the safety of the game, when the oncoming vehicle is in the maximum deceleration, the oncoming vehicle still enters the conflict area, the game ends, and the output game result is yielding.

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