Method for controlling a vehicle with an acc system with deceleration strip detection function and the system

Abstract

The invention relates to a method for controlling a vehicle by means of an adaptive cruise control system, comprising the steps of detecting a speed bump located on the trajectory of the vehicle, determining the distance to the speed bump, the geometry of the speed bump and the current vehicle speed, classifying the speed bump according to its geometry, selecting a speed limit value from a plurality of predetermined speed limit values based on the classification of the speed bump, calculating the required braking intensity based on the current vehicle speed, the distance to the speed bump and the speed limit value, and braking the vehicle according to the calculated intensity. The invention also relates to a system capable of performing the method.

Description

Technical Field

[0001] This invention relates to a method for controlling a vehicle using an adaptive cruise control system (ACC) with speed bump detection, an adaptive cruise control system with speed bump detection, and an advanced driver assistance system (ADAS) incorporating the adaptive cruise control system. Background Technology

[0002] Adaptive cruise control (ACC) is a widely used feature in modern advanced driver assistance systems (ADAS). Currently, almost all new cars are equipped with ACC, primarily for highway driving scenarios. However, ACC also has the potential to enhance driving comfort in urban and rural environments, where it can be configured to maintain the vehicle speed at specified limits (e.g., 30 km / h in city centers) to comply with local regulations.

[0003] In standard ACC (Adaptive Cruise Control) implementations, if there are no other vehicles directly in front, the system maintains a preset speed regardless of surrounding road infrastructure (such as speed bumps). Therefore, the vehicle may drive over these obstacles at the set speed, potentially causing discomfort to occupants and posing a risk of chassis damage, thus adversely affecting the vehicle's durability. Depending on the type of obstacle, its impact and effect on the vehicle vary, requiring corresponding solutions. Summary of the Invention

[0004] Therefore, the object of the present invention is to provide an adaptive cruise control method and system to overcome the above-mentioned defects. Another object of the present invention is to provide a method and system capable of determining and performing the required operation based on the type of speed bump that is an obstacle.

[0005] The above-mentioned objectives are achieved by the method of claim 1, the adaptive cruise control system of claim 7, and the advanced driver assistance system of claim 9. Advantageous embodiments and further improvements of the invention are defined by the dependent claims.

[0006] The method for controlling a vehicle using an adaptive cruise control system as described in this invention includes the following steps: detecting speed bumps located on the vehicle's driving trajectory; determining the distance to the speed bump, the geometry of the speed bump, and the current vehicle speed; classifying the speed bumps according to their geometry; selecting a speed limit based on the type of speed bump; calculating the required braking intensity based on the current vehicle speed, the distance to the speed bump, and the speed limit; and braking the vehicle according to the calculated intensity.

[0007] Applying braking force to the vehicle according to the calculated intensity will decelerate the vehicle to the speed limit. The speed limit may not be a fixed speed such as 20 km / h, but may be a speed range such as 18-22 km / h. If the required braking force is determined to be zero, it means that no braking is required. Therefore, the step of calculating the required braking force may include the step of calculating whether braking is necessary.

[0008] According to one embodiment of the method, it further includes the steps of: determining whether the adaptive cruise control system has set a speed limit; and accelerating the vehicle to the speed limit after detecting that the vehicle has passed over the speed bump. This allows the vehicle to maintain the speed limit set by the user or ACC, without losing speed due to speed bumps.

[0009] According to one embodiment of the method, classifying speed bumps based on their geometry includes classification based on their height and / or width in the vehicle's direction of travel and / or the slope of an uphill ramp and / or the slope of a downhill ramp. Speed ​​bumps can be divided into multiple predetermined categories. For example, these predetermined categories could be the maximum height range of speed bumps detected by the method. These predetermined categories may include combinations of multiple determined features of the speed bumps, or may include subcategories with additional features.

[0010] According to one embodiment of the method, it further includes the steps of: defining a reserved distance from the speed bump based on the vehicle speed and / or a selected permissible speed limit and / or a classified speed bump category; and subtracting the reserved distance from the distance from the speed bump used to calculate the required braking intensity.

[0011] The step of defining a pre-determined distance and subtracting it from the distance to the speed bump used to calculate the required braking intensity can be performed before the step of calculating the required braking intensity based on the current vehicle speed, the distance to the speed bump, and the speed limit. Alternatively, this step can be performed after the above calculation step, followed by repeating the calculation step. The pre-determined distance ensures that the vehicle will not be braking when driving over the speed bump. In other words, because a pre-determined distance of, for example, 2 meters is subtracted from the distance used to calculate the braking intensity, the vehicle's braking will be completed before entering the pre-determined distance range from the speed bump. Therefore, pitching or sinking of the vehicle due to braking when driving over the speed bump can be avoided, as this could significantly exacerbate discomfort for vehicle occupants or damage the vehicle.

[0012] According to one embodiment of the method, defining the reserved distance includes: calculating the pitch angle of the vehicle when braking with a calculated intensity; and, based on the pitch angle, calculating whether the distance between the front chassis of the vehicle and the ground is less than the height determined by the speed bump classification. If so, the reserved distance is subtracted from the distance to the speed bump used to calculate the required braking intensity.

[0013] This means that the allowance distance is subtracted only when the pitch angle causes the distance between the vehicle chassis and the ground to be less than the height determined by the speed bump classification. This distance can be a distance associated with a threshold of increased occupant discomfort, or it can be the height of the speed bump. For example, if the distance is less than the height of the speed bump, the discomfort from driving over the speed bump may be greater than the discomfort from braking; therefore, the increased braking intensity that may be necessary due to the reduced available braking distance is acceptable. In other words, this embodiment allows for a trade-off between the discomfort from braking and the discomfort caused by the vehicle driving over a speed bump at a specific pitch angle. The braking intensity can be calculated as described in the foregoing embodiments.

[0014] According to one embodiment of the method, a first discomfort value is selected from a set of predetermined values ​​based on the calculated braking intensity; a second discomfort value is calculated based on the classification of the speed bump and the vehicle speed; if the discomfort corresponding to the first discomfort value is greater than the discomfort corresponding to the second discomfort value, braking of the vehicle is prohibited.

[0015] This means that the vehicle will only be braked if the discomfort caused by driving over a speed bump at its current speed is greater than the discomfort caused by braking.

[0016] According to one embodiment of the present invention, any one of the speed limit, allowance distance, predetermined distance, and discomfort value can be predefined or selected by the vehicle user. This allows the user to set the driving behavior of ACC according to their own preferences.

[0017] The present invention also relates to an adaptive cruise control system for controlling a vehicle, comprising: a sensor configured to detect a speed bump located on the vehicle's driving trajectory, determine the distance to the speed bump, and determine the geometry of the speed bump; and a controller connected to the sensor and configured to perform the method described in any of the above embodiments.

[0018] The sensor can be a camera sensor, and the controller can be configured to classify speed bumps. Since most new vehicles equipped with ACC already include camera sensors, this method can be applied and implemented without adding any additional components.

[0019] The present invention also relates to an advanced driver assistance system, which includes the adaptive cruise control system described in any of the above embodiments.

[0020] The methods and systems claimed in this invention can minimize the impact of vehicle driving behavior on occupants. Adaptive cruise control systems with speed bump detection can not only detect speed bumps but also reduce discomfort when driving over them by braking the vehicle. This significantly improves driving comfort and protects and extends the service life of vehicle components, such as chassis components. Attached Figure Description

[0021] The preferred embodiments of the method will now be described with reference to the accompanying drawings.

[0022] Figure 1 The driving scenario with speed bumps is shown; Figure 2 The steps of one embodiment of the present invention are shown; Figure 3a -c indicates the execution Figure 2 The vehicle described in the method; Figure 4a The vehicle is shown during braking. Figure 4b A vehicle is shown performing some steps of another embodiment of the invention; Figure 5 It shows Figure 4b The steps of the embodiments of the present invention; Figure 6 The steps of yet another embodiment of the present invention are shown. Detailed Implementation

[0023] Figure 1 A driving scenario is illustrated. In this scenario, a vehicle is traveling on a narrow lane, and a speed bump 10 is located before an intersection. According to one embodiment, a system can detect the speed bump 10 via its sensors and perform [action / action]. Figure 2 The method steps are described below.

[0024] In step S1, the speed bump 10 is detected. This can be achieved by a sensor or by a controller that receives sensor information. For example, the sensor could be a camera sensor that provides image data to the controller, or it could contain an image detection device and directly detect the speed bump 10. The speed bump 10, as a type of obstacle on the road, is detected by its typical characteristics. These characteristics include its strip shape (perpendicular to the vehicle's trajectory in most cases), uphill and downhill sections with different slopes, and its top located between two slopes.

[0025] Step S1 not only detects the speed bump 10, but also determines whether it is located on the vehicle's travel trajectory. Therefore, only the speed bumps that the vehicle will cross when continuing along the current trajectory are considered.

[0026] Figure 3a The image shows vehicle 20 located on driving trajectory 30. This scenario could be... Figure 1 In the scenario shown, speed bump 10 is located on the driving trajectory 30. If vehicle 20 continues to travel along the current trajectory, it will cross speed bump 10.

[0027] After detecting the speed bump 10 located on the driving trajectory 30, step S2 determines the distance to the speed bump 10, the geometry of the speed bump 10, and the current vehicle speed v. The distance D to the speed bump 10 refers to the distance from the front of the vehicle 20 to the starting point of the speed bump 10. The current vehicle speed v is visually represented by the length of an arrow. The current vehicle speed v can be a limited speed set by the adaptive cruise control system. For example, in Figure 1 In the driving scenario shown, the current speed v can be the speed limit for that road segment, such as 30 km / h.

[0028] The geometry of the speed bump 10 may include detecting its height H and / or width W in the direction of travel of the vehicle 20 and / or the slope of the uphill section and / or the slope of the downhill section. Based on the data used for speed bump detection, one or more features may be detected. Typically, the height H and the slope of the uphill section of the speed bump 10 may be detected, as these are the most prominent features visible from the vehicle 20.

[0029] The detected features can be used to classify the speed bump 10 according to its geometry in step S3. Classification can be based on a single feature (such as the height H of the speed bump 10) or on a specific number of features. For example, the speed bump 10 can be divided into one of several predetermined categories. These categories may include height ranges, such as Category I: H = 1-5 cm; Category II: H = 5-10 cm; Category III: H = 10-15 cm; Category IV: H > 15 cm. Each category may contain subcategories to achieve combinations of different features.

[0030] In step S4, a speed limit value v3 is selected based on the category of the speed bump. The speed limit value v3 can be selected from multiple predetermined speed limits, which may include speed limits predetermined for the category to which the speed bump 10 belongs. For example, a single predetermined speed limit of 35 km / h can be defined for Category I, a single predetermined speed limit of 25 km / h can be defined for Category II, and so on. Each category may contain multiple predetermined speed limits, from which one can be selected according to the speed bump category. This allows for defining different speed limits for different subcategories of each category.

[0031] Step S5 calculates the required braking intensity. This calculation is based on the current vehicle speed v, the distance D from the speed bump 10, and the speed limit v3 selected in step S4.

[0032] Following the example above, if the speed bump 10 detected (step S1) is determined (step S2) to have a height between 5 and 10 centimeters, it is classified as Category II (step S3). This category defines a single predetermined speed limit of 25 km / h, which is selected (step S4) and used for calculation. If the current vehicle speed is 33 km / h and the distance D to the speed bump 10 is 10 meters, then step S5 calculates the required braking intensity to ensure that the vehicle 20 reduces to the 25 km / h speed limit before reaching the speed bump 10. Preferably, the calculation of the required braking intensity should ensure that the braking process is completed before reaching the speed bump 10. This can be achieved by incorporating a reserved distance D into the calculation. R The implementation details and related embodiments will be described below. Figure 4b The following description is provided. During braking, vehicle 20 will pitch forward due to inertia, causing the center of gravity to shift to the front wheels. This shift in the center of gravity exerts a downward force on the front suspension and an upward force on the rear suspension, causing the front of the vehicle to drop and the rear to lift. Driving over speed bump 10 in a pitched state may cause discomfort to the occupants and shorten the lifespan of vehicle components due to the additional stress on the suspension. Completing the braking process before driving over speed bump 10 can avoid this situation.

[0033] In step S6, the vehicle 20 is braked according to the calculated intensity. For example, the braking intensity is calculated in a way that ensures the braking process is completed within the time it takes for the vehicle 20 to travel most of the distance D. In this way, the discomfort caused by braking can be minimized while ensuring that the braking process is completed before crossing the speed bump 10. Figure 3b The vehicle 20 in step S6 is shown. The vehicle speed v2 is reduced due to braking, and the distance D between it and the speed bump 10 is partially covered. Figure 3c The image shows the state of vehicle 20 after traveling a distance D and crossing speed bump 10, at which point the vehicle speed v3 is equal to the selected speed limit v3 reached through braking.

[0034] Figure 4a The diagram illustrates the state of vehicle 20 during braking. Due to braking, vehicle 20 experiences a pitch angle, which can be represented by angle α. In this case, angle α refers to the angle between the chassis of vehicle 20 and the travel trajectory 30. The resulting force causes the front of vehicle 20 to drop, reducing the distance H between the front chassis and the surface of the travel trajectory 30. F As mentioned earlier, driving a vehicle over a speed bump in a pitched position may cause discomfort and shorten the lifespan of components. Furthermore, if the distance is H... F If the height H of the speed bump 10 is less than that of the speed bump 10, the chassis of the vehicle 20 may impact the surface of the speed bump 10, thereby damaging the vehicle 20.

[0035] To ensure that vehicle 20 does not pitch when driving over speed bump 10, one embodiment of the method may include step 4a, which can be performed after step S4 of selecting speed limit value v3 (see...). Figure 5 In step 4a, based on the current vehicle speed v and / or the selected speed limit v3 and / or the classified speed bump category, the reserved distance D is selected. R (See Figure 4b For example, higher vehicle speeds v or speed bump categories corresponding to larger speed bump heights H may increase the defined allowance distance D. R Subtract this reserved distance from the distance D between the speed bump 10 and the speed bump to obtain the distance DD. R This distance is then used in step S5 to calculate the required braking intensity. Therefore, it is ensured that the braking process occurs when the vehicle 20 enters the reserved distance D. R The range was completed beforehand, and vehicle 20 was along the reserved distance D. R Sufficient time is allowed to return to a level state during the journey, so that the distance H F The distance was restored to the normal driving distance.

[0036] according to Figure 6 In the embodiment of the invention shown, step S5b includes calculating the pitch angle of the vehicle 20 during calculated intensity braking. Then, the distance between the front chassis of the vehicle 20 and the ground (which can be H) is calculated based on the pitch angle. F Is the height H determined by the classification of the speed bump 10? If so, subtract the reserved distance D from the distance D from the speed bump 10. R Then, repeat step S5, and then execute step S6 based on the recalculated braking intensity. If the calculated distance between the front chassis of vehicle 20 and the ground is greater than the height H determined by the classification of speed bump 10, then the braking intensity calculated in step S5 is directly used to brake vehicle 20 in step S6.

[0037] This embodiment is able to reduce the available braking distance (DD) R The decision is to weigh the discomfort caused by increased braking intensity against the discomfort caused by the vehicle pitching over the speed bump 10 (while also posing a risk that the chassis may impact the speed bump 10).

[0038] The method of the present invention is not limited to the embodiments described above, but covers all embodiments within the scope of the claims. Furthermore, where technically feasible, the embodiments can be combined with each other.

Claims

1. A method for controlling a vehicle (20) via an adaptive cruise control system, comprising the following steps: Detect speed bumps (10) located on the vehicle's (20) driving trajectory; Determine the distance (D) to the speed bump (10), the geometry of the speed bump, and the current vehicle speed (v); They are classified according to the geometry of the speed bumps (10); Select a speed limit (v3) based on the type of speed bump; Based on the current vehicle speed (v) and the distance to the speed bump (D; DD) R ) and the speed limit (v3), calculate the required braking intensity; The vehicle (20) is braked based on the calculated strength.

2. The method for controlling a vehicle (20) via an adaptive cruise control system according to claim 1, wherein, The method further includes the following steps: Determine if the adaptive cruise control system has a speed limit set; and After detecting that the vehicle has passed the speed bump (10), the vehicle is accelerated to the specified speed.

3. The method for controlling a vehicle (20) via an adaptive cruise control system according to any one of the preceding claims, wherein, Classifying the speed bumps (10) according to their geometry includes classifying them according to their height (H) and / or width (W) in the direction of travel of the vehicle (20) and / or the slope of the uphill section and / or the slope of the downhill section.

4. The method for controlling a vehicle (20) via an adaptive cruise control system according to any one of the preceding claims, wherein, The method further includes the following steps: Based on the vehicle speed (v) and / or the selected speed limit (v3) and / or the classified speed bump category, a reserved distance (D) from the speed bump (10) is defined. R );as well as Subtract the reserved distance (D) from the distance (D) to the speed bump (10) used to calculate the required braking intensity. R ).

5. The method for controlling a vehicle (20) via an adaptive cruise control system according to claim 4, wherein, Limited reserved distance (D) R )include: Calculate the pitch angle (α) of the vehicle (20) under calculated intensity braking; and Based on the pitch angle (α), calculate the distance (H) between the front chassis of the vehicle (20) and the ground (30). F If the height (H) is less than that defined by the classification of the speed bump (10), then the reserved distance (D) is subtracted from the distance (D) from the speed bump (10) used to calculate the required braking intensity. R ).

6. The method of controlling a vehicle (20) via an adaptive cruise control system according to any one of the preceding claims, wherein, A first discomfort value is selected from a set of predetermined values ​​based on the calculated braking intensity; a second discomfort value is calculated based on the classification of the speed bump (10) and the vehicle speed (v); and if the discomfort corresponding to the first discomfort value is greater than the discomfort corresponding to the second discomfort value, braking of the vehicle (20) is prohibited.

7. An adaptive cruise control system for controlling a vehicle (20), comprising: The sensor is configured to detect speed bumps (10) located on the driving trajectory of the vehicle (20), determine the distance (D) to the speed bumps (10), and determine the geometry of the speed bumps; as well as A controller, which is connected to the sensor and configured to perform the method of any one of claims 1 to 6.

8. The adaptive cruise control system for controlling a vehicle according to claim 7, wherein, The sensor is a camera sensor.

9. An advanced driver assistance system, comprising the adaptive cruise control system of claim 7 or 8.

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