Whole vehicle control method and system for electric vehicle passing through a red light

Abstract

The present application relates to electric vehicle control technical field, provide a kind of electric vehicle through traffic light whole vehicle control method and system, comprising: obtaining the road surface image in front of vehicle, and the road surface state is identified;Vehicle torque is obtained, and friction coefficient is calculated;Based on road surface state and friction coefficient, determine road surface safety speed;Obtain vehicle front radar information, judge whether there is vehicle in front, if there is vehicle in front, then determine safe following vehicle speed;Vehicle distance stop line distance, green light remaining time vehicle, vehicle available maximum speed and speed limit identification speed are obtained, in combination with road surface safety speed and safe following vehicle speed, judge whether vehicle can pass through traffic light, if can pass through traffic light, then calculate the lowest passing speed, and issue a reminder.Let user more reassuredly drive through traffic light intersection.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of electric vehicle control, and particularly relates to a whole vehicle control method and system for an electric vehicle passing through a red light. BACKGROUND

[0002] The statements in this section merely provide background information related to the present application and do not necessarily constitute the prior art.

[0003] Many drivers are worried or entangled about whether the remaining time is sufficient when passing through a red light, especially novice drivers, which may lead to running a yellow light or a red light; there are also situations of not timely stopping to the road center or zebra crossing, or of stopping down by emergency braking, even leading to rear-end collision due to not timely braking of the rear vehicle, and causing serious traffic accidents; especially in rainy and snowy weather, the driver's grasp of the braking timing will be less accurate, and traffic jams and traffic accidents occur frequently. SUMMARY

[0004] In order to solve the technical problems in the background art, the present application provides a whole vehicle control method and system for an electric vehicle passing through a red light, which estimates whether the vehicle can safely pass through the green light without overspeeding according to the maximum vehicle speed available, the road speed limit, the safe following vehicle speed under the condition of a vehicle in front, and the road surface safe speed under rainy and snowy weather, and informs the user through a large screen display or voice prompt, so that the user can drive more safely through the red light intersection

[0005] In order to achieve the above purpose, the present application adopts the following technical solutions:

[0006] The first aspect of the present application provides a whole vehicle control method for an electric vehicle passing through a red light, which comprises:

[0007] Obtaining the road surface image in front of the vehicle to identify the road surface state; obtaining the vehicle torque to calculate the friction coefficient; determining the road surface safe speed based on the road surface state and the friction coefficient;

[0008] Obtaining the front radar information of the vehicle to determine whether there is a vehicle in front, and if there is a vehicle in front, determining the safe following vehicle speed;

[0009] Obtaining the distance of the vehicle from the stop line, the green light remaining time of the vehicle, the maximum vehicle speed available, and the speed limit sign speed, combining the road surface safe speed and the safe following vehicle speed to determine whether the vehicle can pass through the red light, and if the red light can be passed, calculating the minimum passing speed and issuing a prompt.

[0010] Further, the step of determining whether the vehicle can pass through the red light comprises:

[0011] Determining whether the distance Li of the vehicle from the stop line and the green light remaining time T satisfy: V(T-t)≥Li, wherein V is the maximum vehicle speed available VM , the minimum value of the speed limit sign speed V 一 , the minimum value of the road safety speed Vs and the safe following speed Va, t is the reserved time;

[0012] If it is satisfied, the vehicle can pass the red light, and the minimum passing speed is Vmi n = Li / (T - t);

[0013] If it is not satisfied, the vehicle cannot pass the red light.

[0014] Further, the road safety speed is:

[0015]

[0016] Wherein, V M is the maximum speed available to the vehicle; k is determined according to the road surface state; ξ1 and ξ2 are adjustment parameters; a is a threshold value; μ is the friction coefficient.

[0017] Further, the friction coefficient is: μ = T / (r·m·g), wherein T is the torque, r is the wheel radius, m is the vehicle mass, and g is the acceleration of gravity.

[0018] Further, the determination method of the safe following speed is:

[0019] If the vehicle speed V 本 is equal to or less than the speed of the preceding vehicle V 前 , and the distance is greater than the set value, the safe following speed Va = V 前 .

[0020] If the vehicle speed V 本 is higher than the speed of the preceding vehicle V 前 , and the distance is less than the set value, the safe following speed Va = q × V 前 , wherein q is obtained according to the experiment;

[0021] If the vehicle speed V 本 is lower than the speed of the preceding vehicle V 前 , and the distance is less than the set value, the safe following speed Va = p × V 本 , wherein p is obtained according to the experiment.

[0022] Further, it also includes: when the vehicle cannot pass the red light and the driver gives a deceleration instruction, the vehicle is decelerated by an energy recovery method, and if the energy recovery torque is insufficient, the ESP compensates for the hydraulic brake.

[0023] Further, the deceleration when the vehicle is decelerated by the energy recovery method is a = Li / T, wherein Li is the distance of the vehicle from the stop line, and T is the remaining green light time.

[0024] The second aspect of the present application provides a whole vehicle control system for an electric vehicle to pass a traffic light, comprising:

[0025] a road surface safety vehicle speed determination module configured to: acquire a road surface image in front of the vehicle, identify a road surface state; acquire a vehicle torque, and calculate a friction coefficient; and determine a road surface safety vehicle speed based on the road surface state and the friction coefficient;

[0026] a safe following vehicle speed module configured to: acquire radar information in front of the vehicle, determine whether there is a vehicle in front, and if there is a vehicle in front, determine a safe following vehicle speed;

[0027] a determination module configured to: acquire a distance of the vehicle from a stop line, a remaining time of a green light, a maximum available vehicle speed, and a speed limit sign speed, combine the road surface safety vehicle speed and the safe following vehicle speed, and determine whether the vehicle can pass the traffic light, and if the vehicle can pass the traffic light, calculate a minimum passing speed, and issue a prompt.

[0028] The third aspect of the present application provides a computer readable storage medium having a computer program stored thereon, the program being executed by a processor to implement the steps of the whole vehicle control method for an electric vehicle to pass a traffic light as described above.

[0029] The fourth aspect of the present application provides a computer device comprising a computer readable storage medium, a processor, and a computer program stored on the computer readable storage medium and executable on the processor, the processor executing the program to implement the steps of the whole vehicle control method for an electric vehicle to pass a traffic light as described above.

[0030] Compared with the prior art, the present application has the following beneficial effects:

[0031] The present application estimates whether the vehicle can safely pass the green light without speeding according to the maximum available vehicle speed, the road speed limit, the safe following vehicle speed when there is a vehicle in front, and the road surface safety vehicle speed in rainy and snowy weather, informs the user through a large screen display or voice prompt, and enables the user to drive more safely through the traffic light intersection.

[0032] The present application uses energy recovery to actively limit the vehicle speed when it is determined that the vehicle cannot pass the green light, thereby ensuring the safety of the user. BRIEF DESCRIPTION OF DRAWINGS

[0033] The drawings accompanying the specification of the present application form a part thereof, serve to provide further understanding of the present application, and together with the description of the exemplary embodiments of the present application and the explanation thereof serve to explain the present application, and do not constitute an improper limitation of the present application.

[0034] Figure 1 is a traffic light intersection working condition diagram of the first embodiment of the present application;

[0035] Figure 2 The system block diagram of the electric vehicle of the first embodiment of the present application is shown in the figure.

[0036] Figure 3 The structural schematic diagram of the computer device of the fourth embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely below with reference to the drawings of the embodiments of the present application.

[0038] It should be pointed out that the following detailed description is exemplary and is intended to provide further illustration of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as generally understood by those skilled in the art to which the present application belongs.

[0039] Embodiment one

[0040] The embodiment provides a whole vehicle control method for an electric vehicle passing through a traffic light.

[0041] The whole vehicle control method for the electric vehicle passing through the traffic light provided by the embodiment identifies the remaining time of the traffic light and the distance between the vehicle and the traffic light, estimates whether the vehicle can safely pass through the green light without overspeeding according to the maximum speed available for the vehicle, the road speed limit, the safe following vehicle speed under the condition that there is a vehicle in front, and the safe road speed under the condition of rain and snow, informs the user through large screen display or voice prompt, and actively limits the speed using energy recovery when it is judged that the vehicle cannot pass through the green light, so that the user can drive more safely through the traffic light intersection.

[0042] The whole vehicle control method for the electric vehicle passing through the traffic light provided by the embodiment is suitable for electric vehicles, such as Figure 2 As shown in the figure, the electric vehicle includes an image acquisition unit, a vehicle control system (VCU), a battery management system (BMS), a high-voltage battery, a motor control module (MCU), a motor, a vehicle stability system (ESP), an inverter (DC-DC), a traffic sign recognition system (TSR), an instrument control unit (ICU), a large screen control unit (IHU), and a vehicle accelerator pedal, a gear shifting mechanism, a brake pedal, etc.

[0043] The battery management system (BMS) is responsible for responding to high-voltage connection, calculating charging and discharging power, and sending to the VCU.

[0044] The image acquisition unit adopts a CCD (Charge Coupled Device), acquires real-time images of the road in front of the vehicle, and sends to the VCU.

[0045] Wherein, the motor control module (MCU) real-time collects motor state and responds to the torque command of VCU, and feeds back actual torque and rotating speed to VCU.

[0046] Wherein, the vehicle stability system (ESP) collects vehicle speed and sends to VCU.

[0047] Wherein, the inverter (DC-DC) collects output voltage and current and sends to VCU.

[0048] Wherein, the traffic sign recognition system (TSR) is responsible for identifying traffic lights and speed limit information, and feeding back to VCU.

[0049] Wherein, the large screen control unit (IHU) collects vehicle front radar information, calculates the distance of vehicle to intersection according to GPS positioning, and feeds back to VCU.

[0050] Wherein, the vehicle control system (VCU) interacts with the above controllers through CAN communication, and summarizes information to calculate whether the vehicle can pass through the traffic light intersection within the remaining time of the traffic light under multiple working conditions.

[0051] Wherein, the large screen control unit (IHU) has display and voice reminding functions, and informs the driver according to the information fed back by VCU.

[0052] Wherein, the instrument control unit (ICU) receives the information such as whether the intersection can be passed sent by VCU for display.

[0053] The embodiment provides a kind of whole vehicle control method of electric vehicle through traffic light, vehicle passes through traffic light intersection, from the logical judgment of vehicle distance stop line distance L, including the following steps:

[0054] Step 1, the vehicle control system (VCU) is classified and identified to the road surface image in front of vehicle, and is divided into dry, wet and extremely slippery three road surface states.

[0055] Specifically, the classification step includes: extracting the road area in the image by image segmentation, and removing vehicle interference by adaptive threshold method;After extracting the image texture attribute value and the average value of gray scale in the road area, classification is carried out by Bayes classifier and the like.

[0056] Step 2, based on torque T, calculate the friction coefficient: μ = T / (r·m·g), wherein, r is wheel radius, m is vehicle mass, g is acceleration of gravity, dry asphalt road surface μ is about 0.6-0.8, ice and snow road surface μ is as low as 0.1-0.2.

[0057] Step 3, based on road surface state and friction coefficient μ, determine the safe speed of road surface:

[0058]

[0059] wherein, V M is the maximum vehicle speed available; k is determined according to the road surface state, in this embodiment, 0.7 is taken when the road surface state is dry, 0.4 is taken when the road surface state is wet and slippery, and 0.1 is taken when the road surface state is extremely slippery; and xi and x2 are adjustment parameters; a is a threshold value, and 0.3 is taken; according to the value, when the difference between k and μ is small, it is indicated that the image recognition result and the friction coefficient calculation result are close, and there is no error in the image recognition result or the friction coefficient calculation result caused by other reasons, at this time, the product of the two is used for adjustment, and the speed adjustment effect is obvious; when the difference between k and μ is large, there are other factors affecting the image recognition result or the friction coefficient calculation result, which causes inaccurate calculation, at this time, the median value of the two is taken for adjustment, which can avoid the speed adjustment being too large due to the error and affecting the driving.

[0060] wherein, the maximum vehicle speed available is calculated by the VCU according to the available power of the motor and the battery, and the speed limit when the vehicle fails or the power is limited is considered.

[0061] Step 4, the VCU judges whether there is a vehicle in front based on the front radar information of the vehicle; if there is no vehicle in front, the safe following speed Va = the speed limit sign speed V max , then directly enter step 5; otherwise, the vehicle speed V 本 is obtained (such as V1, V2, V3 and V4 in Figure 1 ), the front vehicle speed V 前 and the distance A between the vehicle and the front vehicle (such as A1, A2 in Figure 1 ) are obtained, the vehicle speed is adjusted, and the safe following speed is obtained:

[0062] (1) if the vehicle speed is equal to or less than the front vehicle speed, and the distance is greater than the set value 3m, the driver is reminded to keep the vehicle speed unchanged or accelerate to be equal to the front vehicle speed, at this time, the safe following speed Va = V 前 .

[0063] (2) if the vehicle speed is higher than the front vehicle speed, and the distance is less than the set value 3m, the driver is reminded to take deceleration measures to reduce the speed and maintain the safe distance, at this time, the safe following speed Va = q x V 前 , wherein q is obtained according to the experiment, and its value is less than 1.

[0064] (3) if the vehicle speed is lower than the front vehicle speed, and the distance is less than the set value 3m, the driver is reminded to take deceleration measures to maintain the safe distance, at this time, the safe following speed Va = p x V 本 , wherein p is obtained according to the experiment, and its value is less than 1.

[0065] Step 5, judge whether the distance Li of the vehicle to the stop line and the remaining green light time satisfy the following formula:

[0066] V(T-t)≥Li

[0067] Wherein, V is the minimum value of the maximum vehicle speed V M , the speed limit sign speed V max , the road safety speed Vs and the safe following speed Va, T is the remaining green light time, t is the user set reserved time (such as 1s), Li is the current distance of the vehicle to the stop line (such as L1, L2, L3, L4 in the above embodiment). Figure 1

[0068] If the above formula is satisfied, the vehicle can normally pass the red and green light, and the minimum passing speed V min = Li / (T-t) is calculated, and the driver is prompted by the large screen control unit, voice or display;

[0069] If the above formula is not satisfied, the vehicle cannot directly pass under the current green light and needs to be slowed down to stop for the next green light, and the driver is prompted by the large screen control unit, voice or display: if the driver does not step on the brake to slow down, the vehicle can be slowed down to 10km / h (which can be calibrated) by the VCU according to the deceleration a=Li / T through energy recovery method, so that the driver can step on the brake at any time, if the energy recovery torque is insufficient, the ESP compensation hydraulic brake can be used to meet the deceleration a requirement, and the VCU judges whether to turn on the brake light or double flash to prompt the rear vehicle; if the driver directly brakes to slow down, the driver's request is directly responded.

[0070] Embodiment two

[0071] The embodiment provides a whole vehicle control system for an electric vehicle to pass a red and green light, which specifically comprises:

[0072] A road safety speed determination module configured to: acquire a road image in front of the vehicle, identify a road state; acquire a vehicle torque, and calculate a friction coefficient; and determine a road safety speed based on the road state and the friction coefficient;

[0073] A safe following speed module configured to: acquire radar information in front of the vehicle, judge whether there is a vehicle in front, and if there is a vehicle in front, determine a safe following speed;

[0074] A judgment module configured to: acquire a distance of the vehicle to a stop line, a remaining green light time of the vehicle, a maximum vehicle speed available to the vehicle and a speed limit sign speed, combine the road safety speed and the safe following speed, judge whether the vehicle can pass the red and green light, and if the vehicle can pass the red and green light, calculate a minimum passing speed and issue a prompt.

[0075] ​It should be noted that each module in the embodiment corresponds to each step in Embodiment One, and the specific implementation process is the same, which will not be repeated here.

[0076] Embodiment Three

[0077] The embodiment provides a computer readable storage medium, which stores a computer program, and the program is executed by a processor to realize steps in a whole vehicle control method of an electric vehicle passing through a traffic light.

[0078] Embodiment Four

[0079] The embodiment provides a computer device, which comprises a display device, an input device, a computer readable storage medium (a volatile memory and a non-volatile storage medium), a processor, a communication interface (i.e., a network interface) and a computer program stored in the computer readable storage medium and capable of running on the processor. Figure 3 As shown in the figure, the processor, the communication interface and the computer readable storage medium are connected through a bus or other means. The communication interface is used to receive and send data, and the processor executes the program to realize steps in the whole vehicle control method of the electric vehicle passing through the traffic light.

[0080] Any reference to memory, storage, database or other medium provided by the present application and used in the embodiments can include non-volatile and / or volatile memory. The non-volatile memory can include read only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. The volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, the RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (SSRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM) and memory bus dynamic RAM (RDRAM) and the like.

[0081] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart or flows and / or block diagram block or blocks. Figure 1 one or more flow or flows and / or block diagram block or blocks. Figure 1 one or more flow or flows and / or block diagram block or blocks.

[0082] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart or flows and / or block diagram block or blocks. Figure 1 one or more flow or flows and / or block diagram block or blocks. Figure 1 one or more flow or flows and / or block diagram block or blocks.

[0083] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart or flows and / or block diagram block or blocks. Figure 1 one or more flow or flows and / or block diagram block or blocks. Figure 1 one or more flow or flows and / or block diagram block or blocks.

[0084] The application described above is merely preferred embodiments of the application, and the application is not limited thereto. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the application shall be included in the protection scope of the application.

Claims

1. A vehicle control method for an electric vehicle passing through a traffic light, characterized by, The method comprises the following steps: acquiring an image of a road surface in front of the vehicle and identifying a road surface state; acquiring a torque of the vehicle and calculating a friction coefficient; determining a safe vehicle speed on the road surface based on the road surface state and the friction coefficient; acquiring radar information of the vehicle in front and determining whether there is a vehicle in front, and if there is a vehicle in front, determining a safe following vehicle speed; acquiring a distance of the vehicle to a stop line, a remaining time of a green light, a maximum available vehicle speed and a speed limit sign speed, combining the safe vehicle speed on the road surface and the safe following vehicle speed, determining whether the vehicle can pass through the red and green light, if the vehicle can pass through the red and green light, calculating a minimum passing speed, and issuing a reminder. The step of judging whether the vehicle can pass the traffic light comprises judging whether the distance Li of the vehicle from the stop line and the remaining green light time T satisfy: , wherein V is the minimum value of V M , the speed limit sign vehicle speed V max , the road safety vehicle speed , and the safe following vehicle speed Va, t is the reserved time; if yes, the vehicle can pass the traffic light, and the minimum passing speed is ; if not, the vehicle cannot pass the traffic light.

2. The whole vehicle control method for an electric vehicle passing a traffic light according to claim 1, characterized by, The safe vehicle speed on the road surface is: where V M is the maximum speed available to the vehicle; k is determined according to the state of the road surface; and is an adjustment parameter; is a threshold value; μ is the coefficient of friction.

3. The vehicle control method of claim 1, wherein, The friction coefficient is: μ = T / (r·m·g), wherein T is the torque, r is the wheel radius, m is the vehicle mass, and g is the acceleration of gravity.

4. The whole vehicle control method for an electric vehicle passing a traffic light according to claim 1, characterized by, The determination method of the safe following vehicle speed is: If the vehicle speed V 本 is equal to or less than the preceding vehicle speed V 前 , and the distance is greater than a set value, the safe following vehicle speed Va=V 前 ; If the vehicle speed V 本 is higher than the front vehicle speed V 前 , and the distance is less than a set value, then the safe following vehicle speed Va=q×V 前 , where the value of q is obtained from experiments; If the vehicle speed V 本 is lower than the front vehicle speed V 前 , and the distance is less than a set value, then the safe following vehicle speed Va = p x V 本 , where the value of p is obtained according to experiments.

5. The whole vehicle control method for an electric vehicle passing a traffic light according to claim 1, characterized by, The method further comprises the following steps: when the vehicle cannot pass through the red and green light and the driver gives a deceleration instruction, decelerating the vehicle through an energy recovery method, and if the energy recovery torque is insufficient, compensating the hydraulic brake through ESP.

6. The whole vehicle control method for an electric vehicle passing a traffic light according to claim 5, characterized by, The deceleration of the vehicle when decelerating by the energy recovery method is where Li is the distance of the vehicle from the stop line, and T is the remaining green light time.

7. A whole vehicle control system for an electric vehicle passing through a traffic light, characterized by, The method comprises the following steps: a road surface safe vehicle speed determination module configured to acquire an image of a road surface in front of the vehicle and identify a road surface state; acquiring a torque of the vehicle and calculating a friction coefficient; determining a safe vehicle speed on the road surface based on the road surface state and the friction coefficient; a safe following vehicle speed module configured to acquire radar information of the vehicle in front and determine whether there is a vehicle in front, and if there is a vehicle in front, determine a safe following vehicle speed; a determination module configured to acquire a distance of the vehicle to a stop line, a remaining time of a green light, a maximum available vehicle speed and a speed limit sign speed, combine the safe vehicle speed on the road surface and the safe following vehicle speed, determine whether the vehicle can pass through the red and green light, if the vehicle can pass through the red and green light, calculate a minimum passing speed, and issue a reminder. The steps for determining whether a vehicle can pass through the traffic light include: determining whether the distance Li from the vehicle to the stop line and the remaining green light time T satisfy the following conditions: Where V is the maximum available vehicle speed V M Speed ​​limit sign, vehicle speed V max Road safety speed The minimum value among the following four factors—safe following speed Va—is taken, where t is the allowance time. If this condition is met, the vehicle can proceed through the traffic light, with a minimum speed of [missing value]. If the conditions are not met, the vehicle may not proceed through the traffic light.

8. A computer-readable storage medium having stored thereon a computer program, characterized in that, The program is executed by the processor to realize the steps in the whole vehicle control method of the electric vehicle passing through the red and green light according to any one of claims 1-6.

9. A computer device comprising a computer readable storage medium, a processor, and a computer program stored on the computer readable storage medium and executable on the processor, characterized in that, The processor executes the program to realize the steps in the whole vehicle control method of the electric vehicle passing through the red and green light according to any one of claims 1-6.

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