A safe time interval control strategy and system when driving

Abstract

The application discloses a safe time interval control strategy and system when driving, and the strategy comprises the following steps: when the forward speed of the current vehicle is greater than a first vehicle speed, starting a safe time interval control function; calculating a following vehicle time interval in real time according to the forward speed of the current vehicle and the distance between the current vehicle and a front target vehicle; when the following vehicle time interval is less than a first time interval or the predicted collision time is less than a first time, issuing a reminder; when the following vehicle time interval is less than a second time interval or the predicted collision time is less than a second time, automatically applying a first braking force to the current vehicle to slow down the current vehicle; and when the following vehicle time interval is greater than a third time interval or the predicted collision time is greater than a third time, automatically releasing the first braking force; wherein the second time interval is less than the first time interval, the third time interval is greater than the first time interval, the second time is less than the first time, and the third time is greater than the first time. The safe time interval control function is started when the conditions are met, and the function greatly improves the safety and comfort of autonomous driving.

Description

Technical Field

[0001] This application relates to the field of automotive driving safety technology, and more specifically, to a safe distance control strategy and system for driving. Background Technology

[0002] With the continuous development of intelligent technology, more active and passive safety technologies are being applied to automobiles. Safety has always been a crucial aspect of automotive development at every stage. In recent years, commonly used driver assistance systems include: Automatic Emergency Braking (AEB), Adaptive Cruise Control (ACC), Smart Cruise Control (SCC), Forward Collision Warning (FCW), and Emergency Lane Keeping Assist (ELK). These systems use cameras, millimeter-wave radar, and other sensors to detect the vehicle's surroundings and identify potential collision risks, promptly alerting the driver or allowing the vehicle to brake or swerve autonomously to ensure safety. In recent years, the driving experience through active and passive safety has also gained increasing attention from major automakers. The pursuit of safety, comfort, and driving pleasure has become an inevitable trend in the development of intelligent vehicles.

[0003] Currently, many vehicles are equipped with ACC and SCC cruise control functions, which utilize cameras, lidar, millimeter-wave radar, and other technologies to detect the vehicle's forward driving environment and achieve intelligent cruise control. This function allows the vehicle to stay within its lane and follow the vehicle in front. When the vehicle in front accelerates, decelerates, or stops, the vehicle will automatically decelerate, stop, start, and accelerate according to the cruise control's set speed and following distance. This function can greatly reduce the driver's stress and workload. However, ACC / SCC systems are used infrequently in complex urban traffic. This is because complex urban traffic involves many vehicles, pedestrians, and intersections. Vehicles need to cope with various vehicles cutting in and out at various intersections and curves. The lag in ACC and SCC's frequent identification of new CIPV targets and their corresponding deceleration and acceleration can reduce driving safety and traffic efficiency. In addition, the ACC / SCC system will deactivate and enter standby mode after the driver applies the brakes or makes a sharp turn, requiring the driver to reactivate the function. In urban driving, this leads to frequent system entry into standby mode, requiring the driver to frequently reactivate the function, resulting in insufficient convenience of use.

[0004] In addition, there are FCW and AEB systems, whose main function is to warn of an impending collision and bring the vehicle to a timely stop to avoid an accident. FCW and AEB systems activate when a collision is imminent, designed to trigger warnings and emergency braking in emergency situations to ensure avoidance or mitigation of a collision. However, when following too closely to another vehicle, if the vehicle in front suddenly brakes, the driver may not react in time, leading to a rear-end collision. Even if AEB is triggered, it may still cause a rear-end collision. Triggering, falsely triggering, or failing to trigger AEB in a timely manner all contribute to a poor driving experience for the driver.

[0005] In summary, existing vehicle active and passive safety technologies fail to achieve the expected driving safety and comfort, resulting in a poor user experience. Summary of the Invention

[0006] This application provides a safe following distance control strategy and system. The safe following distance control function is activated when certain conditions are met. Once activated, this function will not affect normal driving and will not be frequently deactivated. The driver can control the vehicle's acceleration, deceleration, and steering at any time. Appropriate braking force is automatically applied to decelerate (rather than stop) only when the following distance is too small or the risk of collision is very high. When the vehicle is safe again, the applied braking force is automatically released and normal driving resumes. It only serves to control vehicle speed and distance, reduce the occurrence of collisions, or mitigate collision damage, while greatly enhancing the sense of security and comfort of autonomous driving.

[0007] This application provides a safe distance control strategy during driving, including:

[0008] When the forward vehicle speed exceeds the first speed limit, the safe distance control function is activated.

[0009] The following distance is calculated in real time based on the vehicle's forward speed and its distance from the target vehicle ahead;

[0010] A warning will be issued when the following distance is less than the first time distance or the estimated collision time is less than the first time interval.

[0011] When the following distance is less than the second time distance or the expected collision time is less than the second time, the first braking force is automatically applied to decelerate the vehicle. When the following distance is greater than the third time distance or the expected collision time is greater than the third time, the first braking force is automatically released.

[0012] Among them, the second time interval is less than the first time interval, and the third time interval is greater than the first time interval; the second time is less than the first time, and the third time is greater than the first time.

[0013] Preferably, when the following distance is less than the first following distance, the following distance display on the instrument panel is red.

[0014] Preferably, when the following distance is less than the second following distance, the following distance display on the instrument panel turns red, and a voice reminder is given that the following distance is less than the threshold.

[0015] Preferably, the safe distance control function is activated when the reversing speed is greater than the second speed.

[0016] The system calculates the estimated collision time in real time based on the vehicle's reversing speed and its distance from the target vehicle or obstacle behind it.

[0017] When the expected collision time is less than the fourth time, the second braking force is automatically applied to decelerate the vehicle; when the expected collision time is greater than the fourth time, the second braking force is automatically released.

[0018] Preferably, the braking deceleration of the braking force is greater than or equal to the preset deceleration.

[0019] This application also provides a safe driving distance control system, including a start condition judgment module, a calculation module, a reminder module, and a braking module;

[0020] The activation condition judgment module is used to activate the safe distance control function when the current vehicle speed is greater than the first vehicle speed.

[0021] The calculation module is used to calculate the following distance in real time based on the vehicle's forward speed and its distance from the target vehicle ahead;

[0022] The alert module is used to issue an alert when the following distance is less than the first time distance or the expected collision time is less than the first time interval.

[0023] The braking module is used to automatically apply a first braking force to decelerate the vehicle when the following distance is less than a second time distance or the expected collision time is less than a second time. When the following distance is greater than a third time distance or the expected collision time is greater than a third time, the first braking force is automatically released.

[0024] Among them, the second time interval is less than the first time interval, and the third time interval is greater than the first time interval; the second time is less than the first time, and the third time is greater than the first time.

[0025] Preferably, the safe following distance control system also includes an instrument panel, and when the following distance is less than a first following distance, the following distance display on the instrument panel is red.

[0026] Preferably, when the following distance is less than the second following distance, the following distance display on the instrument panel turns red, and a voice reminder is given that the following distance is less than the threshold.

[0027] Preferably, the start condition judgment module is also used to activate the safe distance control function when the reversing speed is greater than the second speed;

[0028] The calculation module is also used to calculate the estimated collision time in real time based on the vehicle's reversing speed and its distance from the target vehicle or obstacle behind it;

[0029] The braking module is also used to automatically apply a second braking force to decelerate the vehicle when the expected collision time is less than the fourth time, and to automatically release the second braking force when the expected collision time is greater than the fourth time.

[0030] Preferably, the braking deceleration of the braking force is greater than or equal to the preset deceleration.

[0031] Other features and advantages of this application will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0032] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the present application and, together with their description, serve to explain the principles of the present application.

[0033] Figure 1 A flowchart of the safe distance control strategy for driving provided in this application;

[0034] Figure 2 A schematic diagram illustrating the detection range of the camera and radar provided in this application;

[0035] Figure 3 The structural diagram of the safe driving distance control system provided in this application;

[0036] Figure 4 This is a structural diagram of one embodiment of the safe driving distance control system provided in this application. Detailed Implementation

[0037] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0038] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0039] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the specification.

[0040] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0041] This application provides a safe following distance control strategy and system. The safe following distance control function is activated when certain conditions are met. Once activated, this function does not affect normal driving and is not frequently deactivated. The driver can control the vehicle's acceleration, deceleration, and steering at any time. Appropriate braking force is automatically applied to decelerate (rather than stop) only when the following distance is too small or the risk of collision is very high. When the vehicle is safe again, the applied braking force is automatically released and normal driving resumes. It only serves to control vehicle speed and distance, reduce the occurrence of collisions, or mitigate collision damage. At the same time, it greatly enhances the sense of security and comfort of autonomous driving, aiming to help drivers reduce collisions and mitigate collision damage while enjoying the fun and excitement of autonomous driving.

[0042] like Figure 1 As shown, the safe driving distance control strategy provided in this application includes:

[0043] S110: When the forward speed is greater than the first speed (e.g., 15 kph), activate the safe distance control function.

[0044] As an example, the safe distance control function can be turned on or off in the vehicle's infotainment system, or it can be activated automatically.

[0045] S120: Calculates following distance in real time based on the vehicle's forward speed and the distance to the target vehicle ahead.

[0046] Figure 2 The detection ranges of the radar and cameras are given. Figure 2 As shown, the detection area of ​​the front camera is 0~150M directly in front of the vehicle; the detection area of ​​the front radar is 0~70M directly in front of the vehicle; and the detection areas of the left and right radars are 0~30M directly in front of the vehicle.

[0047] After the front radar and camera identify the target vehicle ahead, they will display a model of the vehicle ahead on the instrument panel and show the following distance. When the following distance is reasonable and there is no risk of rear-end collision, the following distance on the instrument panel will be displayed in green.

[0048] S130: Issue a warning when the following distance is less than the first time distance or the estimated time to collision (TTC) is less than the first time.

[0049] Preferably, when the following distance is less than the first following distance, the following distance display on the instrument panel is red.

[0050] S140: When the following distance is less than the second time distance or the estimated collision time is less than the second time, the first braking force is automatically applied to decelerate the vehicle. When the following distance is greater than the third time distance or the estimated collision time is greater than the third time, the first braking force is automatically released. The first braking force is different from the AEB system; this function does not need to stop the vehicle, but only controls the speed and distance.

[0051] For stationary or low-speed target vehicles, braking is mainly initiated in advance based on TTC. Whether based on following distance or TTC, whichever reaches the braking working condition first will trigger braking. The braking deceleration should be greater than or equal to the preset deceleration (e.g., -5m / s²) to ensure comfort and safety.

[0052] Preferably, when the following distance is less than the second following distance, the following distance display on the instrument panel turns red, and a voice reminder is given that the following distance is less than the threshold (i.e., the distance is too close).

[0053] Among them, the second time interval is less than the first time interval, and the third time interval is greater than the first time interval; the second time is less than the first time, and the third time is greater than the first time.

[0054] Preferably, the safe driving distance control strategy provided in this application further includes:

[0055] S150: When the reversing speed is greater than the second speed (e.g., 3 kph), the safe distance control function is activated.

[0056] S160: Calculates the estimated collision time in real time based on the vehicle's reversing speed and the distance between it and the target vehicle or obstacle behind it.

[0057] S170: When the expected collision time is less than the fourth time, the second braking force is automatically applied to decelerate the vehicle; when the expected collision time is greater than the fourth time, the second braking force is automatically released.

[0058] Preferably, the safe driving distance control strategy provided in this application further includes:

[0059] S180: When the vehicle's forward speed exceeds the third speed limit while turning, the safe distance control function is activated.

[0060] S190: Calculates the distance and relative speed between the vehicle and surrounding vehicles in real time based on the vehicle's forward speed and its distance from the target vehicle ahead and vehicles traveling in the same direction to the side.

[0061] S1100: When the expected collision time is less than the fifth time, the third braking force is automatically applied to decelerate the vehicle; when the expected collision time is greater than the fifth time, the third braking force is automatically released.

[0062] Table 1 provides an example of the threshold values ​​for forward driving, reversing, and vehicle steering (yawing).

[0063]

[0064] Based on the above, this application also provides a safe driving distance control system. For example... Figure 3As shown, the safe distance control system during driving includes a start-up condition judgment module 310, a calculation module 320, a reminder module 330, and a braking module 340.

[0065] The start condition judgment module 310 is used to start the safe distance control function when the current vehicle speed is greater than the first vehicle speed.

[0066] The calculation module 320 is used to calculate the following distance in real time based on the vehicle's forward speed and its distance from the target vehicle ahead.

[0067] The reminder module 330 is used to issue a reminder when the following distance is less than the first time distance or the expected collision time is less than the first time.

[0068] The braking module 340 is used to automatically apply a first braking force to decelerate the vehicle when the following distance is less than a second time distance or the expected collision time is less than a second time. When the following distance is greater than a third time distance or the expected collision time is greater than a third time, the first braking force is automatically released.

[0069] The second time interval is less than the first time interval, and the third time interval is greater than the first time interval. The second time is less than the first time, and the third time is greater than the first time.

[0070] Preferably, the safe following distance control system also includes an instrument panel 350, which displays the following distance in red when the following distance is less than a first following distance.

[0071] Preferably, when the following distance is less than the second following distance, the following distance display on the instrument panel 350 turns red, and a voice reminder is given that the following distance is less than the threshold.

[0072] Preferably, the start condition judgment module 310 is also used to start the safe distance control function when the reversing speed is greater than the second speed.

[0073] The calculation module 320 is also used to calculate the estimated collision time in real time based on the vehicle's reversing speed and its distance from the target vehicle or obstacle behind it.

[0074] The braking module 340 is also used to automatically apply a second braking force to decelerate the vehicle when the expected collision time is less than the fourth time, and to automatically release the second braking force when the expected collision time is greater than the fourth time.

[0075] Preferably, the start condition judgment module 310 is also used to start the safe distance control function when the forward speed of the vehicle is greater than the third speed when the vehicle is turning.

[0076] The calculation module 320 is also used to calculate the distance and relative speed between the vehicle and surrounding vehicles in real time based on the vehicle's forward speed and its distance from the target vehicle in front and the vehicles traveling in the same direction to the side.

[0077] The braking module 340 is also used to automatically apply a third braking force to decelerate the vehicle when the expected collision time is less than the fifth time, and to automatically release the third braking force when the expected collision time is greater than the fifth time.

[0078] This application does not impose restrictions on the entities responsible for calculating following distance and estimated collision time, or on the actuators for applying braking force, as long as they are controllers capable of performing these functions. This functional system includes numerous components (MPC module, PDC module, Body Controller (BCM), EPC controller, ICU instrument controller, etc.), but is not limited to these. The system can monitor and control following distance and automatically release the brakes at a safe following distance, enabling safe driving and reversing while maintaining stable safety and comfort. The interaction method is not limited to instrument displays or voice alarms; ultimately, it aims to help drivers drive safely, promptly mitigate collision risks, and simultaneously ensure driving pleasure and comfort.

[0079] Figure 4 One example is given. Figure 4 In this system, the Electronic Stability Control (ESC) system monitors both forward and reverse vehicle speeds. When the forward speed exceeds 15 kph, the safe distance control function is activated. At this time, the Multimedia Personal Computer (MPC) controller calculates the following distance and estimated time of collision (TTC) in real time. If TTC ≤ 1.5s or the following distance ≤ 0.5s, continuous braking is applied until TTC > 1.5s or the following distance > 0.5s, at which point the braking is released. When the reverse speed is ≥ 3 kph, the safe distance control function is activated. At this time, the Parking Distance Control (PDC) system calculates the estimated time of collision in real time. If TTC ≤ 1s, continuous braking is applied until TTC > 1s, at which point the braking is released.

[0080] Once activated, the safe following distance control function of this application can not only identify vehicles in front and behind and issue warnings and deceleration, but also warn and decelerate vehicles to the side. All deceleration is much gentler than that of the automatic braking system (AEB), making following safer. Pre-deceleration and reasonable control of following distance can effectively avoid rear-end collisions caused by following too closely. It pursues safety and comfort, allowing drivers to fully experience the joy of driving while ensuring driving safety, providing a better sense of driving safety and comfort, and enhancing the customer's car ownership experience.

[0081] While specific embodiments of this application have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of this application. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of this application. The scope of this application is defined by the appended claims.

Claims

1. A safe time gap control strategy for driving, characterized by, The method comprises: starting the safety time interval control function when the forward vehicle speed is greater than a first vehicle speed; calculating the following time interval in real time according to the forward vehicle speed of the ego vehicle and the distance between the ego vehicle and the front target vehicle; issuing a warning when the following time interval is less than a first time interval or the estimated collision time is less than a first time; automatically applying a first braking force to decelerate the ego vehicle when the following time interval is less than a second time interval or the estimated collision time is less than a second time, and automatically releasing the first braking force when the following time interval is greater than a third time interval or the estimated collision time is greater than a third time; wherein the second time interval is less than the first time interval, the third time interval is greater than the first time interval; the second time is less than the first time, and the third time is greater than the first time; starting the safety time interval control function when the reverse vehicle speed is greater than a second vehicle speed; calculating the estimated collision time in real time according to the reverse vehicle speed of the ego vehicle and the distance between the ego vehicle and the rear target vehicle or obstacle; automatically applying a second braking force to decelerate the ego vehicle when the estimated collision time is less than a fourth time, and automatically releasing the second braking force when the estimated collision time is greater than the fourth time; starting the safety time interval control function when the forward vehicle speed is greater than a third vehicle speed when the vehicle is turning; calculating the distance and relative speed between the ego vehicle and the surrounding vehicles in real time according to the forward vehicle speed of the ego vehicle and the distance between the ego vehicle and the front target vehicle and the side target vehicle traveling in the same direction; automatically applying a third braking force to decelerate the ego vehicle when the estimated collision time is less than a fifth time, and automatically releasing the third braking force when the estimated collision time is greater than the fifth time.

2. The safe time-to-collision control strategy of claim 1, wherein, When the following time interval is less than the first time interval, the following time interval display on the instrument panel is red.

3. The on-road safety time gap control strategy of claim 2, wherein, When the following time interval is less than the second time interval, the following time interval display on the instrument panel is red, and a voice warning is given that the following time interval is less than the threshold value.

4. The safe time interval control strategy for driving while intoxicated according to claim 1, wherein, The braking deceleration of the braking force is greater than or equal to the preset deceleration.

5. A safe time interval control system for use in driving a vehicle, characterized by The method comprises a starting condition judgment module, a calculation module, a warning module, and a braking module; the starting condition judgment module is used to start the safety time interval control function when the forward vehicle speed is greater than a first vehicle speed; the calculation module is used to calculate the following time interval in real time according to the forward vehicle speed of the ego vehicle and the distance between the ego vehicle and the front target vehicle; the warning module is used to issue a warning when the following time interval is less than a first time interval or the estimated collision time is less than a first time; the braking module is used to automatically apply a first braking force to decelerate the ego vehicle when the following time interval is less than a second time interval or the estimated collision time is less than a second time, and automatically release the first braking force when the following time interval is greater than a third time interval or the estimated collision time is greater than a third time; wherein the second time interval is less than the first time interval, the third time interval is greater than the first time interval; the second time is less than the first time, and the third time is greater than the first time; the starting condition judgment module is also used to start the safety time interval control function when the reverse vehicle speed is greater than a second vehicle speed; the calculation module is also used to calculate the estimated collision time in real time according to the reverse vehicle speed of the ego vehicle and the distance between the ego vehicle and the rear target vehicle or obstacle; The brake module is further configured to automatically apply a second brake force to decelerate the ego vehicle when the predicted time to collision is less than a fourth time, and automatically release the second brake force when the predicted time to collision is greater than the fourth time; The start condition judging module is further configured to start the safety time-to-collision control function when the forward vehicle speed is greater than a third vehicle speed when the vehicle is turning; The calculation module is further configured to calculate the distance and relative speed between the ego vehicle and the surrounding vehicles in real time according to the forward vehicle speed of the ego vehicle and the distance between the ego vehicle and the front target vehicle and the side same-direction vehicle; The brake module is further configured to automatically apply a third brake force to decelerate the ego vehicle when the predicted time to collision is less than a fifth time, and automatically release the third brake force when the predicted time to collision is greater than the fifth time.

6. The in-vehicle time-to-live control system of claim 5, wherein, The instrument panel is further configured to display the time-to-collision distance in red on the instrument panel when the time-to-collision distance is less than a first time-to-collision distance.

7. The in-vehicle time-to-live control system of claim 6, wherein, The instrument panel is further configured to display the time-to-collision distance in red on the instrument panel and remind the driver through voice when the time-to-collision distance is less than a second time-to-collision distance.

8. The in-vehicle time-to-live control system of claim 5, wherein, The brake force has a brake deceleration greater than or equal to a preset deceleration.

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