Intelligent speed regulation system and method for entering and exiting ramp, computer storage medium and vehicle

Abstract

The invention provides an intelligent speed regulation system and method for entering and exiting a ramp, a computer storage medium and a vehicle. Comprising an acquisition module used for acquiring vehicle and road parameters, a ramp recommended speed calculation module used for calculating a ramp recommended speed, a first acceleration module used for obtaining a first acceleration recommended speed value based on the vehicle and road parameters and the ramp recommended speed, and a second acceleration module used for obtaining a second acceleration recommended speed value based on the first acceleration recommended speed value. The second acceleration module is used for obtaining a second acceleration recommended speed value based on the vehicle and road surface parameters and the first acceleration recommended speed value; and the control module is used for controlling the vehicle to accelerate. According to the method, a more reasonable speed regulation scheme is provided for a driver according to the road condition of the actual ramp, and in the process of driving out of the ramp, the vehicle is accelerated quickly for the first time, so that the speed difference between the vehicle and other vehicles is reduced, the safety of the vehicle is ensured, and the risk of traffic accidents is reduced; and carrying out second acceleration and freely driving by the driver.

Description

Technical Field

[0001] The present invention belongs to the technical field of auxiliary safe driving and intelligent traffic control, and specifically relates to an intelligent speed regulation system and method for entering and exiting ramps, a computer storage medium and a vehicle. Background Art

[0002] When a driver is driving a vehicle on a highway or expressway, he or she sometimes needs to enter a ramp to change the driving route. Since the ramps are all curved, it is difficult for the vehicle to turn in time if the speed is too fast. This situation is also a challenge to the lateral grip of the tires. Once the road surface is slippery, it is easy to skid, causing the vehicle to collide with the roadbed on both sides of the ramp, which is dangerous. Therefore, it is necessary to maintain a specific speed when the vehicle is driving on the ramp. However, since the speed of vehicles on highways and expressways is relatively fast, it is generally greater than the specific speed when the vehicle safely passes the ramp. Therefore, in most cases, the vehicle needs to slow down in advance before entering the ramp and accelerate again after exiting the ramp, which causes many problems.

[0003] Before entering the ramp, if the driver slows down too early, the driver will need to drive the vehicle for a long time, which will increase the relative speed between the vehicle and other vehicles on the main road, greatly increasing the risk of traffic accidents; if the driver slows down too late, the vehicle may accelerate too much during deceleration, resulting in a poor driving experience for the driver, and sudden deceleration may easily lead to rear-end collisions. Similarly, after exiting the ramp, if the driver accelerates too early, driving safety cannot be guaranteed; if the driver accelerates too late, the speed difference between the vehicle and other vehicles will be too large, greatly increasing the risk of traffic accidents.

[0004] In summary, during driving, providing drivers with reasonable speed control solutions that have both driving safety and driving comfort for different ramps has become an urgent problem to be solved by technical personnel in this field. Summary of the invention

[0005] The purpose of the present invention is to solve the above-mentioned problems existing in the prior art, and provide an intelligent speed regulation system, method, computer storage medium and vehicle for entering and exiting a ramp, aiming to assist the driver in adjusting the speed of the vehicle before the vehicle enters the ramp and after the vehicle exits the ramp by means of lane number and navigation information, so as to ensure that the vehicle passes the ramp safely; and to avoid sudden acceleration and deceleration before entering the ramp and after the vehicle exits the ramp, so as to ensure the comfort of the driving process.

[0006] One of the inventive objectives of the present invention is to provide an intelligent speed control system for an on-ramp and off-ramp, comprising:

[0007] An acquisition module, used to acquire vehicle and road parameters;

[0008] A ramp recommended speed calculation module, used for receiving the vehicle and road parameters, and obtaining the ramp recommended speed based on the vehicle and road parameters;

[0009] a first acceleration module, configured to receive the vehicle and road surface parameters, the ramp recommended speed, and obtain a first acceleration recommended speed value based on the vehicle and road surface parameters and the ramp recommended speed; or configured to receive the vehicle and road surface parameters and obtain the first acceleration recommended speed value based on the vehicle and road surface parameters;

[0010] a second acceleration module, configured to receive the vehicle and road parameters and the first acceleration recommended speed value, and obtain a second acceleration recommended speed value based on the vehicle and road parameters and the first acceleration recommended speed value;

[0011] The control module is configured to receive the first acceleration recommended speed value and the second acceleration recommended speed value and control vehicle acceleration.

[0012] In a preferred embodiment of the present invention, the vehicle and road parameters include but are not limited to the friction coefficient between the vehicle tires and the road surface, the local gravity acceleration, the curvature radius of the ramp, the number of lanes, the current maximum speed limit of the main road, the current vehicle speed, the upper speed limit, and the lower speed limit.

[0013] In a preferred embodiment of the present invention, the ramp recommended speed calculation module obtains the ramp recommended speed using the following formula:

[0014]

[0015] In formula (1), v 0 is the recommended speed for the ramp; N 1 is the first conversion parameter; μ is the friction coefficient between the vehicle tire and the road surface; g is the local acceleration of gravity; R is the curvature radius of the ramp.

[0016] In a preferred embodiment of the present invention, the first acceleration module obtains the first acceleration recommended speed value using the following formula:

[0017] v 3 =v 0 +K(v 4 -v 0 ) Formula (3)

[0018] In formula (3), v 3 v is the recommended speed value for the first acceleration; 0 is the recommended ramp speed; K is the speed conversion parameter; v 4 The speed value of the current maximum speed limit on the main road.

[0019] In a preferred implementation manner of the present invention, the second acceleration recommended speed value is 80-100% of the current main road maximum speed limit.

[0020] In a preferred embodiment of the present invention,

[0021] The control module is used to receive the first acceleration recommended speed value, and control the vehicle to accelerate the vehicle from the ramp recommended speed to the first acceleration recommended speed value within a first preset acceleration distance; and / or

[0022] The control module is used to receive the second acceleration recommended speed value, and control the vehicle to accelerate the vehicle from the first acceleration recommended speed value to the second acceleration recommended speed value within a second preset acceleration distance;

[0023] Preferably,

[0024] The first preset acceleration distance is 50 to 250 m; and / or

[0025] The second preset acceleration distance is 50 to 250 m;

[0026] More preferably,

[0027] After the first acceleration module calculates the first recommended acceleration speed value, based on the ramp recommended speed, the first recommended acceleration speed value and the first preset acceleration distance, the first acceleration is calculated and sent to the control module; the control module controls the vehicle to accelerate at the first acceleration; and / or

[0028] After receiving the first recommended acceleration speed value, the vehicle and road parameters, the second acceleration module calculates a second acceleration based on the first recommended acceleration speed value, the vehicle and road parameters, and the second preset acceleration distance and sends it to the control module; the control module controls the vehicle to accelerate at the second acceleration.

[0029] In a preferred embodiment of the present invention, the on-ramp and off-ramp intelligent speed regulation system further comprises:

[0030] a first deceleration module, configured to receive the vehicle and road parameters and the ramp recommended speed, and obtain a first deceleration recommended speed value based on the vehicle and road parameters and the ramp recommended speed;

[0031] a second deceleration module, configured to receive the first deceleration recommended speed value and the ramp recommended speed, and obtain a second deceleration based on the first deceleration recommended speed value and the ramp recommended speed;

[0032] Preferably,

[0033] The control module is used to receive the first deceleration recommended speed value, and control the vehicle to decelerate from the current vehicle speed to the first deceleration recommended speed value within a first preset deceleration distance; and / or

[0034] The control module is used to receive the second deceleration and control the vehicle to decelerate the vehicle from the first deceleration recommended speed value to the ramp recommended speed within a second preset deceleration distance;

[0035] More preferably,

[0036] The first preset deceleration distance is 400-600m; and / or

[0037] The second preset deceleration distance is 200 to 300 meters.

[0038] In a preferred embodiment of the present invention, the first deceleration module obtains the first deceleration recommended speed value using the following formula:

[0039] v 2 =v 1 -N 2 (v 1 -v 0 ) Formula (4)

[0040] In formula (4), v 2 v is the recommended speed value for the first deceleration; 1 is the current vehicle speed; N 2 is the conversion parameter; v 0 Recommended speed for ramps;

[0041] Preferably, the conversion parameter is set to a value of 0.3 to 0.5.

[0042] In a preferred embodiment of the present invention, the on-ramp and off-ramp intelligent speed regulation system further comprises:

[0043] The judgment module is used to take the smaller value between the ramp recommended speed and the vehicle speed lower limit as the optimized ramp recommended speed.

[0044] The second object of the present invention is to provide an intelligent speed control method for an on-ramp or off-ramp, which is performed using the intelligent speed control system for an on-ramp or off-ramp described in the first object of the present invention, and specifically comprises the following steps:

[0045] S1: Obtain vehicle and road parameters;

[0046] S2: Based on vehicle and road parameters, obtain the recommended ramp speed;

[0047] S3: when the vehicle reaches a preset acceleration position, based on the vehicle and road surface parameters, the ramp recommended speed, or based on the vehicle and road surface parameters, a first acceleration recommended speed value is obtained; and the vehicle is controlled to accelerate from the ramp recommended speed to the first acceleration recommended speed value; and / or

[0048] When the vehicle accelerates to a first recommended acceleration speed value, based on the vehicle and road parameters and the first recommended acceleration speed value, a second recommended acceleration speed value is obtained; the vehicle is controlled to accelerate from the first recommended acceleration speed value to the second recommended acceleration speed value; and / or

[0049] When the vehicle reaches a preset deceleration position, based on the vehicle and road parameters and the ramp recommended speed, a first deceleration recommended speed value is obtained; the vehicle is controlled to decelerate from the current speed to the first deceleration recommended speed value; and / or

[0050] When the vehicle decelerates to the first recommended deceleration speed value, the vehicle is controlled to decelerate from the first recommended deceleration speed value to the ramp recommended speed.

[0051] The third object of the present invention is to provide a computer-readable storage medium, wherein the computer-readable storage medium stores at least one computer-executable program, and the at least one program includes the intelligent speed control system for entry and exit ramps described in one of the objects of the present invention.

[0052] A fourth object of the present invention is to provide a vehicle comprising the computer-readable storage medium described in the third object of the present invention.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] 1. The intelligent speed control system for entering and exiting the ramp of the present invention provides the driver with a more reasonable speed control scheme according to the actual road conditions of the ramp. When exiting the ramp, the vehicle accelerates quickly for the first time to reduce the speed difference between the vehicle and other vehicles, ensure vehicle safety, and reduce the risk of traffic accidents; then the second acceleration is performed and the driver can drive freely. Before entering the ramp, the vehicle decelerates a little to avoid sudden deceleration to ensure the driver's driving experience; then the vehicle decelerates quickly to finally make the vehicle speed equal to the recommended speed when entering the ramp, ensuring that the vehicle passes the ramp at a more reasonable speed without causing danger, thus ensuring vehicle safety.

[0055] 2. The intelligent speed control system for entering and exiting the ramp of the present invention provides a reasonable acceleration plan in the process of exiting the ramp, combining the number of lanes, the current maximum speed limit of the main road and the recommended speed of the ramp, avoiding sudden acceleration while narrowing the speed difference with other vehicles as quickly as possible to ensure safety. Before entering the ramp, a reasonable deceleration plan is provided in combination with the recommended speed of the ramp and the current vehicle speed, instructing the driver to decelerate the current vehicle speed to the recommended speed in a safer and more reasonable manner and enter the ramp. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 It is a schematic diagram of the intelligent speed regulation system for the on-ramp and off-ramp of the present invention;

[0057] Figure 2 A schematic diagram of an intelligent speed regulation method for an on-ramp and off-ramp of the present invention;

[0058] Figure 3 A diagram showing the relationship between the vehicle speed and time before entering the ramp in the intelligent speed control method for entering and exiting the ramp of the present invention;

[0059] Figure 4 This is a graph showing the relationship between vehicle speed and time after exiting the ramp in the intelligent speed regulation method for on- and off-ramp of the present invention. DETAILED DESCRIPTION

[0060] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0061] Example 1

[0062] like Figure 1 As shown, the present invention provides an intelligent speed control system for ramps, including an acquisition module, a ramp recommended speed calculation module, a first acceleration module, a second acceleration module and a control module. The following will describe the five modules in detail.

[0063] Get Module , used to obtain vehicle and road parameters. Preferably, the vehicle and road parameters include but are not limited to the friction coefficient μ between the vehicle tire and the road surface, the local gravity acceleration g, the curvature radius R of the ramp, the number of lanes n, the current main road maximum speed limit value v 4 、Current vehicle speed v 1 , upper speed limit, and lower speed limit. More specifically, Get Module Used to obtain the friction coefficient μ between the vehicle tires and the road surface, the local gravity acceleration g, the curvature radius R of the ramp, the number of lanes n, and the current maximum speed limit v of the main road 4 、Current vehicle speed v 1 , upper speed limit, and lower speed limit. Among them, the local gravity acceleration g, the curvature radius R of the ramp, the friction coefficient μ between the vehicle tires and the road surface, the number of lanes n, and the current main road maximum speed limit v 4 , the upper speed limit, and the lower speed limit are all stored in the database, and the acquisition module can directly call these seven data. It should be noted that the friction coefficient μ between the vehicle tire and the road surface is obtained from the test in the previous experiment, and it is stored in the database after the test is completed. 1 Obtained through the vehicle speed sensor.

[0064] Ramp Recommended speed calculation module, and is in communication connection with the acquisition module; the ramp recommended speed calculation module is used to receive the vehicle and road parameters, and obtain the ramp recommended speed v based on the vehicle and road parameters 0 Preferably, the ramp recommended speed calculation module is used to receive the friction coefficient μ between the vehicle tire and the road surface, the local gravity acceleration g, and the curvature radius R of the ramp sent by the acquisition module, and calculate the ramp recommended speed v based on the friction coefficient μ between the vehicle tire and the road surface, the local gravity acceleration g, and the curvature radius R of the ramp. 0 It should be noted that the recommended ramp speed v 0 The recommended speed for the ramp you are about to enter is v. This is because different ramps have different optimal speeds. 0 The specific value of is related to the curvature radius R of the ramp, the friction coefficient μ between the vehicle tires and the road surface, and the gravitational acceleration g.

[0065] Specifically, the calculation process of the ramp recommended speed calculation module is shown in formula (1):

[0066]

[0067] In formula (1), v 0 is the recommended speed for the ramp; N 1 is the first conversion parameter; μ is the friction coefficient between the vehicle tire and the road surface; g is the local gravity acceleration; R is the curvature radius of the ramp. It should be noted that the "maximum speed" here refers to the maximum speed v of the vehicle without deviation calculated based on the curvature radius R, friction coefficient μ, and gravity acceleration g. max The specific calculation method is as follows and will not be repeated here.

[0068] The derivation process of formula (1) is as follows: first calculate the maximum static friction force f between the vehicle tire and the road surface, then assume that the vehicle speed is v when passing the current ramp, calculate the required centripetal force under the condition of speed v, and then make the required centripetal force less than or equal to the maximum static friction force f, so as to complete the physical model of the vehicle not skidding when passing the ramp. The physical model of the vehicle not skidding when passing the ramp is shown in formula (2):

[0069]

[0070] In formula (2), μ is the friction coefficient between the vehicle tire and the road surface; m is the total mass of the vehicle (unit: kg); g is the local acceleration of gravity; f is the maximum static friction between the vehicle tire and the road surface; v (unit: m / s) is the speed of the vehicle when passing the current ramp; R is the curvature radius of the ramp.

[0071] In order to ensure that the friction between the vehicle tires and the road surface can provide the centripetal force for the vehicle to turn, the vehicle speed needs to be as small as possible and less than or equal to a certain value, which is the maximum speed v passing the ramp. max Theoretically, the maximum static friction f between the vehicle tire and the road is equal to the centripetal force The maximum speed of the ramp can be calculated by formula (2). In actual driving, as long as the vehicle speed is less than the maximum speed v max , which can ensure the safe passage of vehicles on the ramp.

[0072] The maximum speed v is calculated in the present invention max After that, the recommended ramp speed v is given 0 You can set it according to your needs. However, in order to ensure the safe passage of vehicles, it is necessary to ensure the recommended ramp speed v 0 Strictly less than the maximum speed v max Therefore, the ramp recommended speed v is calculated according to formula (1) in the present invention: 0 ; In some cases, N 1 Set to 0.9, which is the recommended ramp speed v 0 Set to 0.9 times the maximum speed v max It should be noted that N 1 The value 0.9 is only used for exemplary purposes, and those skilled in the art may set the value to other values ​​less than 1.0 as required.

[0073] It can be seen that in actual use, the ramp recommended speed calculation module only needs to receive the curvature radius R of the next ramp, the local gravity acceleration g, and the friction coefficient μ between the vehicle tire and the road surface sent by the acquisition module to calculate the ramp recommended speed.

[0074] The first acceleration module , and is in communication with the ramp recommended speed calculation module and the acquisition module; the first acceleration module is used to receive the vehicle and road parameters, the ramp recommended speed v 0 , and based on the vehicle and road parameters, the ramp recommended speed v 0 Get the first acceleration recommended speed value v 3 or for receiving the vehicle and road parameters and obtaining a first acceleration recommended speed value v based on the vehicle and road parameters 3 Specifically, the first acceleration module is used to receive the ramp recommended speed v sent by the ramp recommended speed calculation module. 0 and for receiving the lane number n and the speed value v of the current maximum speed limit of the main road sent by the acquisition module 4 , and based on the ramp recommended speed v 0, the number of lanes n, the current maximum speed limit of the main road v 4 Calculate the first recommended acceleration speed value v for exiting the ramp 3 , to initially accelerate quickly and quickly reduce the speed difference between the vehicle and other vehicles after the vehicle exits the ramp, thereby reducing the risk of traffic accidents.

[0075] According to the driving habits of most drivers, when the number of lanes n is large, the speed of the vehicle is relatively fast; when the number of lanes n is small, the speed of the vehicle is relatively slow, but still maintains a relatively high speed. In order to enable the vehicle to reduce the speed difference with vehicles in other lanes more quickly, thereby reducing the risk of traffic accidents, the present invention sets the first acceleration recommended speed value v when the vehicle exits the ramp and merges into the main road 3 , the number of lanes n is considered.

[0076] Specifically, the calculation process of the first acceleration module is shown in formula (3):

[0077] v 3 =v 0 +K(v 4 -v 0 ) Formula (3)

[0078] In formula (3), v 3 v is the recommended speed value for the first acceleration; 0 is the recommended ramp speed; K is the speed conversion parameter; v 4 is the speed value of the current maximum speed limit on the main road. It should be noted that the speed conversion parameter K is directly related to the number of lanes n, and the corresponding relationship between the two is shown in Table 1. As can be seen from Table 1, in general, the number of lanes is 2, 3, 4 or greater than 4. According to the number of lanes n in Table 1, the speed conversion parameter K corresponding to the number of lanes n can be queried and substituted into formula (3). Combined with the recommended ramp speed v 0 and the current main road maximum speed limit value v 4 , the first recommended acceleration speed value v can be calculated 3 .

[0079] Table 1 Conversion table of lane number n and speed conversion parameter K

[0080] Number of lanes n 2 3 >＝4 Speed ​​conversion parameter K 0.6 0.7 0.8

[0081] Second acceleration module , and is in communication connection with the first acceleration module and the acquisition module; the second acceleration module is used to receive the vehicle and road parameters, the first acceleration recommended speed value v 3 , and based on the vehicle and road parameters, the first acceleration recommended speed value v 3 Get the second acceleration recommended speed value v 5; The control module is used to receive the first acceleration recommended speed value v 3 and the second acceleration recommended speed value v 5 The second acceleration module is used to receive the first acceleration recommended speed value v sent by the first acceleration module. 3 and a speed value v for receiving the current maximum speed limit of the main road sent by the acquisition module 4 , and based on the first acceleration recommended speed value v 3 , the current maximum speed limit of the main road v 4 Calculate the second recommended acceleration speed value v for exiting the ramp 5 , so that the vehicle can accelerate for the second time after the first acceleration after exiting the ramp and adjusting the vehicle speed to a higher speed. It should be noted that the second acceleration recommended speed value v 5 The speed value v can be slightly lower than the current maximum speed limit of the main road 4 , or the speed required by the driver. Preferably, the second acceleration recommended speed value v 5 is the speed value v of the maximum speed limit 4 When the vehicle speed reaches the second acceleration recommended speed value v 5 Just maintain the current speed and drive at a constant speed.

[0082] Control Module , connected to the first acceleration module and the second acceleration module; the control module is used to receive the first acceleration recommended speed value v 3 and the second acceleration recommended speed value v 5 Specifically, the control module is used to receive the first acceleration recommended speed value v sent by the first acceleration module. 3 , and control the vehicle to accelerate from the ramp recommended speed v within the first preset acceleration distance 0 Accelerate to the first recommended acceleration speed value v 3 The control module is used to receive the second acceleration recommended speed value v sent by the second acceleration module 5 , and controls the vehicle to accelerate from the first recommended acceleration speed value v within the second preset acceleration distance 3 Accelerate to the second recommended acceleration speed value v 5 .

[0083] It should be noted that when the vehicle reaches the preset acceleration position (i.e., when exiting the ramp), the first acceleration module and the control module are triggered; wherein the first acceleration module receives the ramp recommended speed v 0 , the number of lanes n and the current maximum speed limit of the main road v 4 , calculate the first recommended acceleration speed value v 3 , sent to the control module; the control module receives the first acceleration recommended speed value v3 , and control the vehicle to accelerate from the ramp recommended speed v within the first preset acceleration distance 0 Accelerate to the first recommended acceleration speed value v 3 When the vehicle accelerates to the first recommended acceleration speed value v 3 , triggering the second acceleration module and the control module; wherein the second acceleration module receives the first acceleration recommended speed value v 3 , the current maximum speed limit of the main road v 4 , get the second acceleration recommended speed value v 5 , sent to the control module; the control module receives the second acceleration recommended speed value v 5 , and controls the vehicle to accelerate from the first recommended acceleration speed value v within the second preset acceleration distance 3 Accelerate to the second recommended acceleration speed value v 5 In addition, the present invention determines whether the vehicle has exited the ramp based on the map positioning information, that is, determines whether the vehicle has reached the preset acceleration position based on the map positioning information. This is a conventional method in the art and will not be described in detail here.

[0084] Preferably, the first preset acceleration distance is 50 to 250 m; and / or the second preset acceleration distance is 50 to 250 m. For example, after exiting the ramp, the vehicle starts to accelerate, and the ramp recommended speed v 0 Accelerate to the first recommended acceleration speed value v 3 It needs to be completed within 250m. After exiting the ramp and accelerating for the first time, the vehicle accelerates for the second time from the first recommended speed value v 3 Accelerate to the second recommended acceleration speed value v 5 Need to be completed within 250 meters.

[0085] Furthermore, the first acceleration module calculates and obtains the first acceleration recommended speed value v 3 Then, based on the ramp recommended speed v 0 、The first acceleration recommended speed value v 3 and the first preset acceleration distance L, calculate the first acceleration a, and send it to the control module, the control module controls the vehicle to accelerate with the first acceleration, so that the vehicle accelerates from the ramp recommended speed v within the first preset acceleration distance L 0 Accelerate to the first recommended acceleration speed value v 3 The calculation process of the first acceleration a is shown in formula (5):

[0086]

[0087] In formula (5), v 3 v is the recommended speed value for the first acceleration; 0is the recommended speed for the ramp; a is the first acceleration; t is the acceleration time; and L is the first preset acceleration distance.

[0088] Similarly, the second acceleration module calculates and receives the first acceleration recommended speed value v 3 and the current main road maximum speed limit value v 4 After that, based on the first acceleration recommended speed value v 3 , the current maximum speed limit of the main road v 4 and a second preset acceleration distance, calculate a second acceleration, and send it to the control module, the control module controls the vehicle to accelerate with the second acceleration, so that the vehicle accelerates from the first recommended acceleration speed value v within the second preset acceleration distance 3 Accelerate to the second recommended acceleration speed value v 5 In another preferred embodiment of the present invention, within the second preset distance, the acceleration is 0.4-0.8 m / s 2 , more preferably 0.6 m / s 2 , in order to further improve the driver's driving comfort.

[0089] In a preferred embodiment of the present invention, the on-ramp and off-ramp intelligent speed control system further includes a first deceleration module and a second deceleration module. The following will describe in detail the relationship between the two modules and the acquisition module, the ramp recommended speed calculation module, the first acceleration module, the second acceleration module, and the control module.

[0090] The first reduction module , and is in communication with the ramp recommended speed calculation module and the acquisition module; the first deceleration module is used to receive the vehicle and road parameters, the ramp recommended speed v 0 , and based on the vehicle and road parameters, the ramp recommended speed v 0 Get the first deceleration recommended speed value v 2 Specifically, the first deceleration module is used to receive the ramp recommended speed v sent by the ramp recommended speed calculation module. 0 and for receiving the current vehicle speed v sent by the acquisition module 1 , and based on the ramp recommended speed v 0 and current vehicle speed v 1 Calculate the first recommended deceleration speed value v before entering the ramp 2 , so as to slow down a little in advance to facilitate lane changing.

[0091] Specifically, the calculation process of the first deceleration module is shown in formula (4):

[0092] v 2 =v 1 -N 2 (v 1 -v0 ) Formula (4)

[0093] In formula (4), v 2 v is the recommended speed value for the first deceleration; 1 is the current vehicle speed; N 2 is the conversion parameter; v 0 is the recommended speed for the ramp. 2 , recommended ramp speed v 0 and current vehicle speed v 1 Substituting into formula (4), the first deceleration recommended speed value v can be calculated 2 Preferably, the conversion parameter N 2 The value of is 0.3-0.5, preferably 0.4, to avoid excessive deceleration and further improve the driving comfort of the driver.

[0094] The second deceleration module , is in communication with the recommended speed calculation module and the first deceleration module; the second deceleration module is used to receive the first deceleration recommended speed value v 2 and the ramp recommended speed v 0 , and based on the first deceleration recommended speed value v 2 The recommended ramp speed v 0 The second deceleration module is used to receive the ramp recommended speed v sent by the recommended speed calculation module. 0 and for receiving the first deceleration recommended speed value v sent by the first deceleration module 2 , and based on the first deceleration recommended speed value v 2 , recommended ramp speed v 0 The second deceleration of the ramp is obtained so that the vehicle can decelerate faster when approaching the ramp entrance, and finally the vehicle speed when entering the ramp is equal to the ramp recommended speed v 0 When the vehicle speed reaches the ramp recommended speed v 0 Just maintain the current speed and drive at a constant speed.

[0095] The first deceleration module is in communication with the control module, and the control module is used to receive the first deceleration recommended speed value v sent by the first deceleration module. 2 , and control the vehicle to change from the current speed v within the first preset deceleration distance 1 Slow down to the first recommended speed value v 2 The second deceleration module is in communication with the control module, and the control module is used to receive the second deceleration sent by the second deceleration module, and control the vehicle to decelerate from the first recommended deceleration speed value v within the second preset deceleration distance. 2 Slow down to the recommended ramp speed v 0 .

[0096] It should be noted that when the vehicle reaches a preset deceleration position (exemplarily, the preset position is 1 km away from the ramp entrance), the first deceleration module and the control module are triggered; wherein the first deceleration module receives the ramp recommended speed v 0 and current vehicle speed v 1 , calculate the first deceleration recommended speed value v 2 , sent to the control module; the control module receives the first deceleration recommended speed value v 2 , and control the vehicle to change from the current speed v within the first preset deceleration distance 1 Slow down to the first recommended speed value v 2 When the vehicle decelerates to the first recommended deceleration speed value v 2 , triggering the second deceleration module and the control module; wherein the second deceleration module receives the first deceleration recommended speed value v 2 , recommended ramp speed v 0 , obtain the second deceleration and send it to the control module; the control module receives the second deceleration and controls the vehicle to decelerate from the first recommended deceleration speed value v within the second preset deceleration distance 2 Slow down to the recommended ramp speed v 0 In addition, the present invention determines whether the vehicle is about to enter the ramp according to the map positioning information, that is, determines whether the vehicle reaches the preset deceleration position according to the map positioning information. This is a conventional method in the art and will not be repeated here.

[0097] Preferably, the first preset deceleration distance is 400-600m; and / or the second preset deceleration distance is 200-300m. Exemplarily, when the vehicle reaches the preset deceleration position, it starts to decelerate, and the current vehicle speed v 1 Slow down to the first deceleration recommended speed value v 2 It needs to be completed within 500m. When the vehicle decelerates to the first recommended deceleration speed value v 2 When the vehicle is decelerated from the first recommended speed value v 2 Slow down to the recommended ramp speed v 0 Need to be completed within 250 meters.

[0098] It should be noted that the first deceleration module calculates the first deceleration recommended speed value v 2 Then, based on the current vehicle speed v 1 、The first deceleration recommended speed value v 2 and the first preset deceleration distance L 1 , calculate the first deceleration and send it to the control module, the control module controls the vehicle to decelerate at the first deceleration to achieve the vehicle within the first preset deceleration distance from the current vehicle speed v 1 Slow down to the first deceleration recommended speed value v 2 Similarly, the second deceleration module receives the first deceleration recommended speed value v2 and ramp recommended speed v 0 Then, based on the first deceleration recommended speed value v 2 , recommended ramp speed v 0 and a second preset deceleration distance, calculate a second deceleration, and send it to a control module, the control module controls the vehicle to decelerate at the second deceleration, so that the vehicle decelerates from the first recommended deceleration speed value v within the second preset deceleration distance. 2 Slow down to the recommended ramp speed v 0 .

[0099] In a preferred embodiment of the present invention, the on-ramp and off-ramp intelligent speed regulation system further includes a judgment module connected to the acquisition module, the ramp recommended speed calculation module, the first acceleration module, and the first deceleration module; the judgment module is used to obtain the ramp recommended speed v 0 and the lower speed limit as the smaller value of the optimized ramp recommended speed. Specifically, the judgment module is used to compare the ramp recommended speed v sent by the ramp recommended speed calculation module. 0 and the lower speed limit sent by the acquisition module (obtained based on the number of lanes n and Table 2), and the smaller one is used as the final optimized ramp recommended speed v 优 , sent to the first acceleration module and the first deceleration module. The subsequent first acceleration recommended speed value v 3 、The first deceleration recommended speed value v 2 The recommended speed of the optimized ramp is v 优 Recommended speed v as ramp 0 Perform calculations.

[0100] Table 2 Number of lanes and upper and lower speed limits on urban roads

[0101]

[0102]

[0103] The speed regulation method of this implementation mode adjusts the vehicle speed to a lower level to ensure driving safety. This method can simplify the driver's deceleration action, reduce the restrictions on the driver's actions under complex road conditions, and provide more operating space for the driver to deal with complex road conditions.

[0104] Example 2

[0105] like Figure 2 As shown, the present invention provides an intelligent speed regulation method for an entry and exit ramp, comprising the following steps:

[0106] S1: Obtain vehicle and road parameters.

[0107] Specifically, the friction coefficient μ between the vehicle tires and the road surface, the local gravity acceleration g, the curvature radius R of the ramp, the number of lanes n, and the current maximum speed limit v of the main road are obtained. 4 、Current vehicle speed v 1 Among them, the local gravity acceleration g, the curvature radius R of the ramp, the friction coefficient μ between the vehicle tires and the road surface, the number of lanes n, and the current maximum speed limit v of the main road 4 All are stored in the database, and the acquisition module can directly call the five data items. It should be noted that the friction coefficient μ between the vehicle tire and the road surface is obtained from the test in the previous experiment, and it is stored in the database after the test is completed. 1 Obtained through the vehicle speed sensor.

[0108] S2: Based on vehicle and road parameters, get the recommended ramp speed v 0 。

[0109] Specifically, based on the friction coefficient μ between the vehicle tires and the road surface, the local gravity acceleration g, and the curvature radius R of the ramp, the recommended ramp speed v is calculated: 0 Specifically, the calculation process of the ramp recommended speed calculation module is shown in formula (1):

[0110]

[0111] In formula (1), v 0 is the recommended speed for the ramp; N 1 is the first conversion parameter; μ is the friction coefficient between the vehicle tire and the road surface; g is the local gravity acceleration; R is the curvature radius of the ramp. The derivation process of formula (1) has been described in detail above and will not be repeated here.

[0112] S3: When the vehicle reaches a preset position or reaches a preset speed, any step of S31 to S34 is executed.

[0113] Therefore, step S3 includes:

[0114] S31: When the vehicle reaches the preset acceleration position, based on the vehicle and road parameters, the ramp recommended speed v 0 , or based on the vehicle and road parameters, obtain the first acceleration recommended speed value v 3 ; Control the vehicle from the ramp recommended speed v 0 Accelerate to the first recommended acceleration speed value v 3 .

[0115] Specifically, when the vehicle reaches the preset acceleration position, based on the ramp recommended speed v 0 , the number of lanes n, the current maximum speed limit of the main road v 4, get the first recommended acceleration speed value v for exiting the ramp 3 ; Within the first preset acceleration distance, the vehicle is at the recommended speed v of the ramp 0 Accelerate to the first recommended acceleration speed value v 3 Specifically, the calculation process of the first acceleration module is shown in formula (3):

[0116] v 3 =v 0 +K(v 4 -v 0 ) Formula (3)

[0117] In formula (3), v 3 v is the recommended speed value for the first acceleration; 0 is the recommended ramp speed; K is the speed conversion parameter; v 4 The speed value of the current maximum speed limit on the main road.

[0118] S32: When the vehicle accelerates to the first recommended acceleration speed value v 3 When the vehicle and road parameters and the first acceleration recommended speed value v 3 , get the second acceleration recommended speed value v 5 ; Control the vehicle from the first acceleration recommended speed value v 3 Accelerate to the second recommended acceleration speed value v 5 .

[0119] Specifically, when the vehicle accelerates to the first recommended acceleration speed value v 3 When the first acceleration recommended speed value v 3 , the current maximum speed limit of the main road v 4 Calculate the second recommended acceleration speed value v for exiting the ramp 5 ; Within the second preset acceleration distance, the vehicle accelerates from the first recommended speed value v 3 Accelerate to the second recommended acceleration speed value v 5 When the vehicle speed reaches the second acceleration recommended speed value v 5 Just maintain the current speed and drive at a constant speed.

[0120] S33: When the vehicle reaches the preset deceleration position, based on the vehicle and road parameters, the ramp recommended speed v 0 , get the first deceleration recommended speed value v 2 ; Control the vehicle from the current speed v 1 Slow down to the first recommended speed value v 2 .

[0121] When the vehicle reaches the preset deceleration position, based on the ramp recommended speed v 0 and current vehicle speed v 1Calculate the first recommended deceleration speed value v before entering the ramp 2 ; Within the first preset deceleration distance, the vehicle changes from the current speed v 1 Slow down to the first recommended speed value v 2 Specifically, the calculation process of the first deceleration module is shown in formula (4):

[0122] v 2 =v 1 -N 2 (v 1 -v 0 ) Formula (4)

[0123] In formula (4), v 2 v is the recommended speed value for the first deceleration; 1 is the current vehicle speed; N 2 is the conversion parameter; v 0 is the recommended speed for the ramp. 2 , recommended ramp speed v 0 and current vehicle speed v 1 Substituting into formula (4), the first deceleration recommended speed value v can be calculated 2 .

[0124] S34: When the vehicle decelerates to the first recommended deceleration speed value v 2 When the vehicle is controlled to decelerate at the first recommended speed value v 2 Slow down to the recommended ramp speed v 0 .

[0125] When the vehicle decelerates to the first recommended deceleration speed value v 2 When the ramp recommended speed v 0 , recommended ramp speed v 0 The second deceleration of the vehicle entering the ramp is obtained; within the second preset deceleration distance, the vehicle is decelerated from the first recommended deceleration speed value v 2 Slow down to the recommended ramp speed v 0 When the vehicle speed reaches the ramp recommended speed v 0 Just maintain the current speed and drive at a constant speed.

[0126] It should be noted that the numbering of steps S31 to S34 does not limit the execution order, and when the triggering condition of any one of the four steps is met, the corresponding instruction can be executed.

[0127] Combine the following Figure 3 The acceleration method after exiting the ramp (ie, step S31 and step S32 ) is exemplarily described.

[0128] S31: When the vehicle just exits the ramp (i.e. before time t4), the acquisition module obtains the lane number n of the current main road and the speed value v of the current maximum speed limit of the main road 4 ; The first recommended acceleration speed value v is calculated by formula (3) 3 Then, starting from time t4, the vehicle starts to accelerate quickly within the next 50 to 250 meters until the vehicle speed reaches the first recommended acceleration speed value v at time t5. 3 .

[0129] S32: Starting from time t5, the vehicle accelerates slowly within a distance of 50 to 250 meters until, at time t6, the vehicle speed reaches a speed value v slightly less than the current maximum speed limit of the main road. 4 speed or the speed required by the driver and maintain a constant speed.

[0130] The speed regulation process of S31 and S32 can be summarized as follows: after exiting the ramp, the vehicle is initially accelerated quickly to reduce the speed difference between the vehicle and other vehicles, and then the vehicle speed is freely adjusted according to the needs of the driver or accelerated to a speed value v slightly less than the current maximum speed limit of the main road. 4 The speed of the vehicle.

[0131] Combine the following Figure 4 The deceleration method before entering the ramp (i.e., step S33 and step S34) is exemplarily described. Assuming that the current vehicle speed v 1 =120km / h, the recommended ramp speed v is calculated according to steps S1 and S2 0 =70km / h.

[0132] S33: When the vehicle reaches a position 1 km away from the ramp entrance, set to time t1, the current vehicle speed v detected by the vehicle speed sensor 1 =120km / h, the ramp recommended speed v is obtained through the ramp recommended speed calculation module 0 =70km / h; According to formula (4), v 2 =100km / h(N 2 =0.4). Then, starting from time t1, within the next 400-600 meters, the speed is reduced by 0.4 times the speed difference, so that the vehicle speed is reduced to the first recommended deceleration speed value v at time t2. 2 =100km / h. That is, at time t2, the vehicle speed drops to 100km / h.

[0133] S34: From time t2, the vehicle speed is reduced to v in the next 200 to 300 meters until time t3. 0 =70km / h. Speed ​​decelerates to v 0 =70km / h, maintain a constant speed of 70km / h and drive through the ramp.

[0134] The speed regulation process of S33 and S34 can be summarized as follows: before entering the ramp, the vehicle is decelerated a little in advance to facilitate lane change; when the vehicle approaches the ramp entrance, it is decelerated faster, and finally the speed of the vehicle entering the ramp is equal to the ramp recommended speed v 0 , and then pass the ramp at a constant speed.

[0135] Example 3

[0136] Since the speed limit on urban roads is generally less than or equal to 80 km / h, the speed difference between vehicles is small, and the speed is generally between 50-80 km / h. At the same time, since the distance of urban roads is shorter than that of highways and the traffic volume is larger, it is difficult to instruct the driver to complete more complex speed control actions in urban roads with more complex road conditions. The present invention also provides a simplified intelligent speed control method for entry and exit ramps for urban roads.

[0137] When the vehicle exits the ramp, step S31 can also be replaced by the following steps: based on the number of lanes n, obtain the first recommended acceleration speed value v 3 Specifically, when the vehicle just exits the ramp, the number of lanes n of the current main road is obtained. According to the obtained number of lanes n, the corresponding upper speed limit is obtained in combination with Table 2, and the upper speed limit is used as the first acceleration recommended speed value v 3 Within the first preset acceleration distance, the vehicle changes from the ramp recommended speed v 0 Accelerate to the first recommended acceleration speed value v 3 .

[0138] S32: Based on the first acceleration recommended speed value v 3 , the current maximum speed limit of the main road v 4 Calculate the second recommended acceleration speed value v for exiting the ramp 5 Within the second preset acceleration distance, the vehicle accelerates from the first recommended acceleration speed value v 3 Accelerate to the second recommended acceleration speed value v 5 When the vehicle speed reaches the second acceleration recommended speed value v 5 Just maintain the current speed and drive at a constant speed.

[0139] The speed control method of this embodiment uses the average speed of normal driving on the main road of each lane as the upper speed limit and the speed after initial acceleration on the exit ramp to ensure that the vehicle accelerates in time and reduce the speed difference with other vehicles. The lowest speed at which the main road of each lane can travel smoothly is used as the lower speed limit to ensure that all vehicles can pass normally and reduce traffic jams.

[0140] In a preferred embodiment of the present invention, when the vehicle is about to enter the ramp, step S33 may further include the following steps: obtaining a lower speed limit based on the number of lanes n; obtaining a lower speed limit based on the lower speed limit and the ramp recommended speed v 0 , get the optimized ramp recommended speed v 优 Specifically, before the vehicle enters the ramp on the urban road section, the method in step S2 is used to calculate the recommended ramp speed v 0 (N 1 Set to 0.8). Get the number of lanes n on the main road after the ramp; Based on the obtained number of lanes n, and in combination with Table 2, get the corresponding lower speed limit. Compare the recommended speed v of the ramp 0 and the lower speed limit, the smaller one is taken as the final optimized ramp recommended speed v 优 . Based on the optimized ramp recommended speed v 优 and current vehicle speed v 1 Calculate the first recommended deceleration speed value v before entering the ramp 2 Within the first preset deceleration distance, the vehicle changes from the current speed v 1 Slow down to the first recommended speed value v 2 .

[0141] S34: Recommended speed v based on optimized ramp 优 , recommended ramp speed v 0 The second deceleration of the vehicle entering the ramp is obtained. Within the second preset deceleration distance, the vehicle is decelerated from the first recommended deceleration speed value v 2 Slow down to the recommended ramp speed v 0 When the vehicle speed reaches the optimized ramp recommended speed v 优 Just maintain the current speed and drive at a constant speed.

[0142] Since the curvature radius of the ramp in the city is small, the speed regulation method of this embodiment adjusts the vehicle speed to a lower level to ensure driving safety. This method can simplify the driver's deceleration action, reduce the restrictions on the driver's actions under complex road conditions, and provide more operating space for the driver to deal with complex road conditions.

[0143] The present invention also relates to a computer-readable storage medium, wherein the computer-readable storage medium stores at least one computer-executable program, wherein the at least one program includes the aforementioned intelligent speed control system for on-ramp and off-ramp. The present invention also relates to a vehicle, comprising the computer-readable storage medium.

[0144] The above technical solution is only one implementation mode of the present invention. For those skilled in the art, it is easy to make various types of improvements or modifications based on the principles disclosed in the present invention, and it is not limited to the technical solution described in the above specific embodiments of the present invention. Therefore, the above description is only preferred and does not have a restrictive meaning.

Claims

1. An intelligent speed control system for on-ramp and off-ramp, characterized in that: include: An acquisition module, used to acquire vehicle and road parameters; A ramp recommended speed calculation module, used for receiving the vehicle and road parameters, and obtaining the ramp recommended speed based on the vehicle and road parameters; A first acceleration module, configured to receive the vehicle and road parameters and the ramp recommended speed, and obtain a first acceleration recommended speed value based on the vehicle and road parameters and the ramp recommended speed; or for receiving the vehicle and road parameters and obtaining a first acceleration recommended speed value based on the vehicle and road parameters; a second acceleration module, configured to receive the vehicle and road parameters and the first acceleration recommended speed value, and obtain a second acceleration recommended speed value based on the vehicle and road parameters and the first acceleration recommended speed value; The control module is configured to receive the first acceleration recommended speed value and the second acceleration recommended speed value and control vehicle acceleration.

2. The system according to claim 1, characterized in that The vehicle and road parameters include but are not limited to the friction coefficient between the vehicle tires and the road surface, the local gravity acceleration, the curvature radius of the ramp, the number of lanes, the current maximum speed limit of the main road, the current vehicle speed, the upper speed limit, and the lower speed limit.

3. The system according to claim 1, characterized in that The ramp recommended speed calculation module obtains the ramp recommended speed using the following formula: In formula (1), v0 is the recommended ramp speed; N1 is the first conversion parameter; μ is the friction coefficient between the vehicle tire and the road surface; g is the local gravity acceleration; and R is the curvature radius of the ramp.

4. The system according to claim 1, characterized in that The first acceleration module obtains the first acceleration recommended speed value by using the following formula: v3=v0+K(v4-v0) Formula (3) In formula (3), v3 is the first acceleration recommended speed value; v0 is the ramp recommended speed; K is the speed conversion parameter; and v4 is the speed value of the current main road maximum speed limit.

5. The system according to claim 2, characterized in that The second acceleration recommended speed value is 80-100% of the current main road maximum speed limit.

6. The system according to claim 1, characterized in that The control module is used to receive the first acceleration recommended speed value, and control the vehicle to accelerate the vehicle from the ramp recommended speed to the first acceleration recommended speed value within a first preset acceleration distance; and / or The control module is used to receive the second acceleration recommended speed value, and control the vehicle to accelerate the vehicle from the first acceleration recommended speed value to the second acceleration recommended speed value within a second preset acceleration distance; Preferably, The first preset acceleration distance is 50 to 250 m; and / or The second preset acceleration distance is 50 to 250 m; More preferably, After the first acceleration module calculates the first acceleration recommended speed value, based on the ramp recommended speed, the first acceleration recommended speed value and the first preset acceleration distance, the first acceleration is calculated and sent to the control module; The control module controls the vehicle to accelerate at the first acceleration; and / or After receiving the first recommended acceleration speed value, the vehicle and road parameters, the second acceleration module calculates a second acceleration based on the first recommended acceleration speed value, the vehicle and road parameters, and the second preset acceleration distance and sends the second acceleration to the control module; The control module controls the vehicle to accelerate at the second acceleration.

7. The system according to claim 1, characterized in that The on-ramp and off-ramp intelligent speed control system also includes: a first deceleration module, configured to receive the vehicle and road parameters and the ramp recommended speed, and obtain a first deceleration recommended speed value based on the vehicle and road parameters and the ramp recommended speed; a second deceleration module, configured to receive the first deceleration recommended speed value and the ramp recommended speed, and obtain a second deceleration based on the first deceleration recommended speed value and the ramp recommended speed; Preferably, The control module is used to receive the first deceleration recommended speed value, and control the vehicle to decelerate from the current vehicle speed to the first deceleration recommended speed value within a first preset deceleration distance; and / or The control module is used to receive the second deceleration and control the vehicle to decelerate the vehicle from the first deceleration recommended speed value to the ramp recommended speed within a second preset deceleration distance; More preferably, The first preset deceleration distance is 400-600m; and / or The second preset deceleration distance is 200 to 300 meters.

8. The system according to claim 7, characterized in that The first deceleration module obtains the first deceleration recommended speed value using the following formula: v2=v1-N2(v1-v0) Formula (4) In formula (4), v2 is the first deceleration recommended speed value; v1 is the current vehicle speed; N2 is the conversion parameter; v0 is the ramp recommended speed; Preferably, the conversion parameter is set to a value of 0.3 to 0.

5.

9. The system according to claim 2, characterized in that The on-ramp and off-ramp intelligent speed control system also includes: The judgment module is used to take the smaller value between the ramp recommended speed and the vehicle speed lower limit as the optimized ramp recommended speed.

10. An intelligent speed control method for an entry and exit ramp, characterized in that: include: S1: Obtain vehicle and road parameters; S2: Based on vehicle and road parameters, obtain the recommended ramp speed; S3: when the vehicle reaches a preset acceleration position, a first acceleration recommended speed value is obtained based on the vehicle and road surface parameters, the ramp recommended speed, or based on the vehicle and road surface parameters; and the vehicle is controlled to accelerate from the ramp recommended speed to the first acceleration recommended speed value; and / or When the vehicle accelerates to a first recommended acceleration speed value, based on the vehicle and road parameters and the first recommended acceleration speed value, a second recommended acceleration speed value is obtained; and the vehicle is controlled to accelerate from the first recommended acceleration speed value to the second recommended acceleration speed value; and / or When the vehicle reaches a preset deceleration position, a first deceleration recommended speed value is obtained based on the vehicle and road parameters and the ramp recommended speed; the vehicle is controlled to decelerate from the current speed to the first deceleration recommended speed value; and / or When the vehicle decelerates to the first recommended deceleration speed value, the vehicle is controlled to decelerate from the first recommended deceleration speed value to the ramp recommended speed.

11. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores at least one computer-executable program, and the at least one program includes the intelligent speed regulation system for on-ramp and off-ramp according to any one of claims 1 to 9.

12. A vehicle, characterized in that: Comprising the computer-readable storage medium of claim 11.

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