Method and system for preview control for road joints

Abstract

The present application relates to the field of vehicle control, and more particularly, to a method for identifying a road seam, and a method and system for preview control for a road seam. The invention provides a method for identifying a road joint, the method is applied to a vehicle, and the method comprises the following steps: monitoring the driving state of the vehicle; in response to the driving state satisfying a predetermined condition, calculating a dynamic characteristic of the vehicle based on the driving state; identifying the type of the road surface event based on the dynamic characteristics; in response to the type of the road event being identified as a road seam, a signal indicative of the road seam is sent to a cloud platform along with a current location of the vehicle.

Description

Technical Field

[0001] This application relates to the field of vehicle control, and more specifically, to methods for identifying road joints and methods and systems for pre-aiming control of road joints. Background Technology

[0002] In current electric vehicles, the overall system from the motor to the wheels has low damping, exhibiting underdamped characteristics. Therefore, when driving on wet or slippery roads, it is prone to significant tire slippage, which can even cause vehicle instability in severe cases, greatly affecting the driving experience and driving safety.

[0003] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this application, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0004] If the road surface is consistently wet and slippery over a considerable distance, causing tire slippage, the vehicle's controller can determine that the vehicle is currently on a slippery surface and adjust its control parameters accordingly. However, sometimes most areas of the road surface do not cause tire slippage, with only a few sections (e.g., steel bridge joints) causing severe skidding under specific weather conditions (e.g., rain) or circumstances (e.g., standing water). In such cases, because the time the vehicle spends passing through these sections is very short (typically no more than 100 ms), and because the vehicle's controller needs time to make this determination (i.e., determine if the vehicle is passing through a wet road joint) and adjust its control parameters, by the time the controller determines that the vehicle is passing through these sections, the vehicle has usually already reached a normal road surface that will not cause slippage, and therefore no further adjustment of its control parameters is necessary.

[0005] In addition, other road surface events such as dents, potholes, bumps, and speed bumps can also cause changes in vehicle driving conditions (e.g., vehicle instability), but these road surface events may be eliminated or altered with road maintenance. To make control parameter adjustments more accurate and targeted, it is also necessary to distinguish road joint events from these types of road surface events to avoid inappropriate adjustments to control parameters due to misidentification or changes in road surface events.

[0006] To address or at least mitigate one or more of the above problems, the following technical solutions are provided. The method and system for pre-aiming control of road joints according to one or more embodiments of this application can ensure that road joints are accurately identified and, based on the location of the identified road joints, promptly send signals to one or more vehicles, enabling them to perform pre-aiming control of the road joints, thereby improving the driving experience and ensuring driving safety.

[0007] According to a first aspect of this application, a method for identifying road joints is provided, the method being applied to a vehicle, the method comprising: monitoring the driving state of the vehicle; calculating dynamic characteristics of the vehicle based on the driving state in response to the driving state satisfying predetermined conditions; identifying a type of road surface event based on the dynamic characteristics; and sending a signal indicating the road joint, along with the vehicle's current position, to a cloud platform in response to the type of the road surface event being identified as a road joint.

[0008] As an alternative or supplement to the above solutions, in a method according to an embodiment of this application, the driving state includes: vehicle speed and wheel speed of each wheel, and the predetermined condition includes: the difference between the vehicle speed and one or more of the wheel speeds exceeds a threshold.

[0009] As an alternative or supplement to the above solution, in a method according to an embodiment of this application, the driving state further includes the road surface state, and the predetermined condition further includes: the road surface state is a wet and slippery road surface.

[0010] As an alternative or supplement to the above solutions, in a method according to an embodiment of this application, the dynamic characteristics include: vehicle acceleration, rate of change of wheel speed of each wheel, amount of slip between wheel speed and vehicle speed, and slip time.

[0011] As an alternative or supplement to the above solutions, in a method according to an embodiment of this application, the types of road surface events further include: flyovers, depressions, potholes, speed bumps, and manhole covers.

[0012] According to a second aspect of this application, a method for pre-aiming control of road joints is provided, the method being applied to a cloud platform, the method comprising: receiving from one or more vehicles a first signal indicating a road joint and a location associated with the road joint; marking the road joint on a cloud layer of the cloud platform based on the location; monitoring the positioning and navigation information of the one or more vehicles; and when the positioning and navigation information of one of the one or more vehicles indicates that the vehicle is expected to pass through the location, sending a second signal to the vehicle to cause the vehicle to perform pre-aiming control of the road joint.

[0013] As an alternative or supplement to the above solutions, in a method according to an embodiment of this application, the one or more vehicles are configured to perform pre-aiming control for road joints in response to receiving the second signal.

[0014] As an alternative or supplement to the above solution, in a method according to an embodiment of this application, the method further includes: sending the distance between the vehicle's location and the location and / or the expected time for the vehicle to arrive at the location, together with the second signal, to the vehicle.

[0015] As an alternative or supplement to the above solutions, in a method according to an embodiment of this application, performing pre-aiming control for road joints includes: adjusting control parameters of the brake control unit, the front axle motor, and / or the rear axle motor before the vehicle passes the position.

[0016] According to a third aspect of this application, a system for pre-aiming control of road joints is provided, the system comprising: one or more vehicles and a cloud platform communicatively coupled to the one or more vehicles; the one or more vehicles being configured to: identify road joints; and in response to identifying a road joint, send a first signal indicating the road joint along with the vehicle's current position to the cloud platform; the cloud platform being configured to: in response to receiving the first signal and the current position of the vehicle from one of the one or more vehicles, mark the position of the road joint based on the current position; monitor positioning and navigation information of the one or more vehicles; and when the positioning and navigation information of one of the one or more vehicles indicates that the vehicle is expected to pass through the position, send a second signal to the vehicle to cause the vehicle to perform pre-aiming control of the road joint.

[0017] A method for identifying road seams according to one or more embodiments of this application enables one or more vehicles to identify road seams based on their dynamic characteristics and provide the location of the identified road seams to a cloud platform. The cloud platform can then determine which vehicles will pass through the road seams based on the positioning and navigation of the one or more vehicles and notify these vehicles. In this way, these vehicles can know the location of road seams ahead of them and adjust their control parameters in advance through anticipation control to mitigate or eliminate the potential negative impacts of these road seams, thereby improving the driving experience and ensuring driving safety. Attached Figure Description

[0018] The above and / or other aspects and advantages of this application will become clearer and more readily understood from the following description taken in conjunction with the accompanying drawings, in which the same or similar elements are denoted by the same reference numerals. In the drawings: Figure 1 This is a schematic diagram of a vehicle-cloud architecture 100 according to an embodiment of this application; Figure 2 This is a flowchart of a method 200 for identifying road joints according to an embodiment of this application; Figure 3This is a schematic diagram 300 illustrating the dynamic characteristics of a vehicle passing through a wet road joint according to an embodiment of this application; Figure 4 This is a flowchart of a method 400 for pre-aiming control of road joints according to an embodiment of this application; Figure 5 This is a flowchart of a process 500 in which a vehicle performs pre-aiming control of road joints based on signals from a cloud platform, according to an embodiment of this application. Detailed Implementation

[0019] The following detailed description is merely exemplary in nature and is not intended to limit the disclosed technology or its application and use. Furthermore, it is not intended to be bound by any express or implied theory presented in the foregoing technical fields, background art, or the following detailed description.

[0020] In the following detailed description of the embodiments, numerous specific details are set forth in order to provide a more thorough understanding of the disclosed technology. However, it will be apparent to those skilled in the art that the disclosed technology can be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the description.

[0021] Terms such as "possessing" and "comprising" indicate that, in addition to the units (modules) and steps directly and explicitly stated in the specification and claims, the technical solution of this application does not exclude the presence of other units (modules) and steps not directly or explicitly stated. Terms such as "first" and "second" do not indicate the order of the units in terms of time, space, size, etc., but are merely used to distinguish the units. Furthermore, the steps in this document are not limited to being performed in the order they are written; a step written later may be performed simultaneously with or before a step written earlier.

[0022] Pre-aiming control is an advanced control strategy that improves the control accuracy and stability of a system by acquiring future path information in advance and optimizing control inputs. This application primarily addresses road surface events involving slippery road joints (especially those with metallic surfaces). Pre-aiming control enables vehicles to adjust control parameters in advance to mitigate tire slippage caused by slippery road joints.

[0023] To achieve this type of pre-aiming control, a global map can be built on a cloud platform, and the pre-aiming points (e.g., road joints to be traversed in the future) of one or more vehicles can be determined by real-time monitoring of the positioning and navigation information of one or more vehicles. One or more embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0024] Figure 1 This is a schematic diagram of a vehicle-cloud architecture 100 according to an embodiment of this application. Figure 1 As illustrated in the diagram, this architecture 100 includes a cloud platform 11 and one or more vehicles (e.g., vehicles 102, 104, and 106, collectively referred to as vehicle 10). Each vehicle in vehicle 10 is communicatively coupled to the cloud platform 11 and is capable of transmitting signals to and / or receiving signals from the cloud platform 11 via an onboard communication module. Additionally, the cloud platform can monitor the positioning and navigation information of each vehicle. Figure 1 Only three vehicles 10 (i.e., vehicles 102, 104, and 106) communicatively coupled to the cloud platform 11 are shown schematically. It should be understood that such vehicle-cloud architectures may include more or fewer vehicles.

[0025] Figure 1 The vehicle-cloud architecture 100 illustrated in the figure can serve as a system for pre-aiming control of road seams according to an embodiment of this application. The system includes one or more vehicles (e.g., vehicles 102, 104, and / or 106) and a cloud platform (e.g., cloud platform 11) communicatively coupled to the one or more vehicles. The one or more vehicles are configured to: identify road seams; and in response to identifying a road seam, send a first signal indicating the road seam along with the vehicle's current position to the cloud platform; the cloud platform is configured to: in response to receiving the first signal and the current position of one of the vehicles from the one or more vehicles, mark the location of the road seam based on the current position; monitor the positioning and navigation information of the one or more vehicles; and when the positioning and navigation information of one of the one or more vehicles indicates that the vehicle is expected to pass through the location, send a second signal to the vehicle to cause the vehicle to perform pre-aiming control of the road seam. Reference will then be made to... Figures 2-5 The process of system operation will be described in detail.

[0026] To determine the location of road seams on the global map of the cloud platform, one or more vehicles can be used to identify road seams on the road surface. For example, if vehicle 102 is traveling in a first direction on a first road, when vehicle 102 identifies a road seam, it can send a signal and its current position to the cloud platform 11. The cloud platform 11 can then determine the location of the road seam on the first road based on this signal and the vehicle's current position. Similarly, the cloud platform 11 can identify road seams on a second road using a second vehicle 104, and on a third road using a third vehicle 106.

[0027] Next reference Figure 2This section describes in detail the process of identifying road joints using vehicles. Figure 2 This is a flowchart of a method 200 for identifying road joints according to an embodiment of this application. Method 200 is applied to vehicles (e.g., Figure 1 The method 200 includes vehicles 102, 104, 106, and / or any other vehicles communicatively coupled to the cloud platform 11, and can be executed by one or more controllers on the vehicles. Method 200 includes: in step 202, monitoring the driving state of the vehicles, the driving state including the vehicle speed and the wheel speeds of each wheel, wherein the vehicle speed can be obtained in various ways, such as derived from wheel speeds or calculated based on Global Positioning System (GPS) signals. Then, in step 204, determining whether the driving state meets predetermined conditions. The predetermined conditions include the difference between the vehicle speed and one or more of the wheel speeds exceeding a threshold. When the difference between the vehicle speed and one or more of the wheel speeds exceeds the threshold, it means that there may be road surface events such as road joints, depressions, potholes, bumps (which may cause fly-offs), speed bumps, etc., on the road, and at this time, the road surface event recognition algorithm is triggered.

[0028] As mentioned above, road joints with metallic surfaces (e.g., steel bridge joints) may be more slippery in rainy or flooded conditions, making their identification potentially easier. In some embodiments, a vehicle may determine whether the weather in its current driving area is sunny or rainy via an external weather system (or based on its own rain sensor), and consequently, whether the current road surface condition is dry or slippery. Accordingly, the driving state also includes the condition of the road surface the vehicle is traveling on, and the predetermined condition further includes the condition that the road surface is slippery.

[0029] Next, in step 206, in response to the driving state meeting predetermined conditions, the vehicle's dynamic characteristics are calculated based on the driving state. These dynamic characteristics include: vehicle acceleration, the rate of change of wheel speeds of each wheel, the amount of slip between the wheel speeds of each wheel and the vehicle speed, and the slip time. The vehicle acceleration, the rate of change of wheel speeds of each wheel, the amount of slip between the wheel speeds of each wheel and the vehicle speed, and the slip time can be obtained through simple calculations (e.g., differentiation, subtraction) using the vehicle speed and the wheel speeds of each wheel.

[0030] Then, in step 208, the type of road surface event is identified based on the dynamic characteristics. Besides road joints, the types of road surface events also include: flyovers, ledges, potholes, speed bumps, and manhole covers. Next, as an example, reference will be made to... Figure 3 This describes how to identify road joints based on dynamic characteristics.

[0031] Figure 3This is a schematic diagram 300 illustrating the dynamic characteristics of a vehicle passing through a slippery road joint according to an embodiment of this application. Specifically, when there are road surface events ahead of the vehicle, the driver may slow the vehicle down to pass through the road ahead. At this time, such as Figure 3 As illustrated by the solid lines, the vehicle's reference speed / reference wheel speed will decrease over time. However, as... Figure 3 As illustrated by the dashed line, when a vehicle's wheels pass through a wet road joint, the vehicle may slip due to the low friction on the wet joint surface. In this case, the wheel speed of the slipping wheel decreases rapidly relative to the vehicle speed. Furthermore, because road joints are typically narrow (e.g., ten centimeters), the slipping wheel quickly recovers after passing through the joint, returning to the same speed as the reference vehicle / wheel speed after a short period of fluctuation.

[0032] In addition, since road joints are usually almost perpendicular to the direction of vehicle travel and run laterally across the road surface, the characteristic wheel speed fluctuations caused by them usually occur simultaneously on both wheels of the same axle (in contrast, road events such as manhole covers and potholes may only affect one side of the wheels), and after occurring on the two wheels of the front axle, they occur on the two wheels of the rear axle in a very short time.

[0033] By utilizing these dynamic characteristics (e.g., both wheels on the same axle simultaneously experiencing large negative slippage lasting less than 200 ms; no large positive slippage; and / or no significant irregular negative slippage), the vehicle can determine that it has traversed a slippery road joint. Similarly, other road surface events have corresponding characteristics, enabling the vehicle's Vehicle Control Unit (VCU) to identify these types of road surface events accordingly. Furthermore, compared to image recognition methods, recognition based on dynamic characteristics does not require the vehicle to be equipped with expensive vision sensors and can have faster computation speeds and / or lower computational resource consumption.

[0034] In some embodiments, the vehicle's VCU may also incorporate the vehicle's pitch angle, acceleration in the vertical direction, and the like to identify other road surface events.

[0035] Next, return Figure 2 In step 210, it is determined whether the identified road surface event is a road joint. As mentioned above, road surface events such as dents, potholes, bumps, and speed bumps may be eliminated or changed during road maintenance, while road joints are almost never changed after road construction. Therefore, marking road joints on the global map of the cloud platform may be more appropriate.

[0036] In step 212, in response to the road surface event being identified as a road joint, a signal indicating the road joint, along with the vehicle's current location, is sent to the cloud platform. Then, in response to the receipt of this signal, the cloud platform can mark the location of the road joint on a global map; this process will be referenced below. Figure 4 It was described in further detail.

[0037] In some embodiments, steps 202-208 can be performed by the vehicle's VCU, and steps 210 and 212 can be performed by a controller on the vehicle that is different from the VCU, such as the Autonomous Driving Controller (ADC). Specifically, the VCU can perform the following operations: driving status monitoring, triggering road event recognition algorithms, and / or identifying road event types. The VCU then provides the identified road event type to the ADC via Controller Area Network (CAN) signals. The ADC can acquire positioning information from GPS and weather information, and send a signal indicating road joints along with the vehicle's current location to the cloud platform (via the vehicle communication module).

[0038] Next reference Figure 4 , Figure 4 This is a flowchart of a method 400 for pre-aiming control of road joints according to an embodiment of this application. Method 400 is applied to a cloud platform (e.g., Figure 1 The method includes: in step 402, from one or more vehicles (e.g., cloud platform 11), the method includes: Figure 1 Vehicles 102, 104, and / or 106 receive a first signal indicating a road joint and the location associated with the road joint (e.g., the vehicle's location at the time the first signal was sent). Then, in step 404, the road joint is marked on a cloud layer (e.g., a global map) of the cloud platform based on its location. Next, in step 406, the positioning and navigation information of the one or more vehicles is monitored until step 408, when the positioning and navigation information of one of the one or more vehicles indicates that the vehicle is expected to pass through the location. Then, the process proceeds to step 410, where a second signal is sent to the vehicle to cause it to perform pre-aiming control for the road joint.

[0039] In some embodiments, method 400 further includes sending the distance between the vehicle's location and the position, and / or the expected time for the vehicle to arrive at the position, along with the second signal, to the vehicle. In this way, the vehicle can more accurately determine how far and / or how long it will take to pass through a slippery road joint, thereby enabling more precise adjustments to the vehicle's control parameters.

[0040] In some embodiments, steps 402 and 404 can be performed by the cloud platform's map marking system, while steps 406-410 can be performed by the cloud platform's vehicle monitoring system, with the two systems communicatively coupled. This arrangement facilitates the modular development and deployment of systems on the cloud platform.

[0041] Next reference Figure 5 , Figure 5 Vehicles according to embodiments of this application (e.g., Figure 1 Vehicle 104 in the middle) is based on signals from the cloud platform (e.g., Figure 4 The flowchart illustrates the process 500 of pre-aiming control for the road joint, executed by the second signal in step 410. Process 500 is performed by a vehicle about to pass through the road joint. In step 502, the vehicle receives information from a cloud platform (e.g., Figure 1 The cloud platform 11) receives a second signal indicating that the vehicle is about to pass through the road joint.

[0042] Furthermore, as mentioned above, the vehicle may also receive additional signals from the cloud platform, indicating the distance between the vehicle's location and the location of the road joint and / or the expected time for the vehicle to arrive at the location. In another embodiment, the vehicle may be configured to automatically perform pre-aiming control after a predetermined time following the receipt of the second signal (thus eliminating the need for additional signals from the cloud platform).

[0043] In some embodiments, the vehicle's ADC can determine whether an ahead road seam will have an impact based on external weather or rain sensors. For example, in clear weather, a road seam may not have a significant impact on the vehicle's wheel speed.

[0044] Then, in step 504, in response to receiving the second signal, the vehicle performs pre-aiming control for the road seam. In some embodiments, performing pre-aiming control for the road seam includes adjusting control parameters of the Brake Control Unit (BCU), the front axle motor, and / or the rear axle motor before the vehicle passes the location. Specifically, based on the second signal (and possibly signals indicating distance and / or time), the vehicle can determine at what time it will pass the slippery road seam. Further, the vehicle can determine at what time each of the two front wheels and the two rear wheels will pass the slippery road seam, and then the vehicle can adjust the control parameters of the Brake Control Unit, the front axle motor, and / or the rear axle motor such that when the two front wheels pass the slippery road seam, torque is provided and / or only brakes are applied to the two rear wheels, and when the two rear wheels pass the slippery road seam, torque is provided and / or only brakes are applied to the two front wheels. In this way, the driving experience when the vehicle passes through slippery road seams can be improved, and driving safety can be ensured.

[0045] Furthermore, as described above, this application can also be implemented as a computer storage medium storing a program for causing a computer to execute the methods described in any of the above embodiments. Here, various types of computer storage media can be used as computer storage media, such as disks (e.g., magnetic disks, optical disks, etc.), cards (e.g., memory cards, optical cards, etc.), semiconductor memory (e.g., ROM, non-volatile memory, etc.), and tapes (e.g., magnetic tape, cassette tape, etc.).

[0046] Where applicable, the various embodiments provided in this application may be implemented using hardware, software, or a combination of hardware and software. Furthermore, where applicable, without departing from the scope of this application, the various hardware and / or software components described herein may be combined into composite components comprising software, hardware, and / or both. Where applicable, without departing from the scope of this application, the various hardware and / or software components described herein may be divided into sub-components comprising software, hardware, or both. Additionally, where applicable, it is contemplated that software components may be implemented as hardware components, and vice versa.

[0047] The software (such as program code and / or data) according to this application can be stored on one or more computer storage media. It is also contemplated that the software identified herein can be implemented using one or more networked and / or otherwise general-purpose or special-purpose computers and / or computer systems. Where applicable, the order of the various steps described herein can be changed, combined into compound steps, and / or divided into sub-steps to provide the features described herein.

[0048] The embodiments and examples presented herein are provided to best illustrate embodiments of this application and its particular applications, thereby enabling those skilled in the art to implement and use this application. However, those skilled in the art will understand that the above description and examples are provided for ease of illustration and example only. The descriptions presented are not intended to cover all aspects of this application or to limit this application to the precise forms disclosed.

Claims

1. A method for identifying road joints, characterized in that, The method is applied to a vehicle, and the method includes: Monitor the driving status of the vehicle; In response to the driving state meeting predetermined conditions, the dynamic characteristics of the vehicle are calculated based on the driving state; Based on the aforementioned dynamic characteristics, the type of road surface event can be identified; In response to the road surface event being identified as a road joint, a signal indicating the road joint, along with the vehicle's current location, is sent to the cloud platform.

2. The method as described in claim 1, wherein, The driving state includes: vehicle speed and wheel speed of each wheel, and the predetermined condition includes: the difference between the vehicle speed and one or more of the wheel speeds exceeds a threshold.

3. The method as described in claim 2, wherein, The driving state also includes the road surface state, and the predetermined condition further includes: the road surface state is a wet and slippery road surface.

4. The method of claim 1, wherein, The dynamic characteristics include: vehicle acceleration, rate of change of wheel speed of each wheel, amount of slip between wheel speed and vehicle speed, and slip time.

5. The method of claim 1, wherein, The types of road surface incidents also include: flyovers, ledges, potholes, speed bumps, and manhole covers.

6. A method for pre-aiming control of road joints, characterized in that, The method is applied to a cloud platform, and the method includes: Receive a first signal indicating a road joint and the location associated with the road joint from one or more vehicles; Based on the location, mark the road joint on the cloud layer of the cloud platform; Monitor the location and navigation information of the one or more vehicles; and When the positioning and navigation information of one or more of the vehicles indicates that the vehicle is expected to pass through the location, a second signal is sent to the vehicle to cause the vehicle to perform pre-aiming control for the road joint.

7. The method of claim 6, wherein, The one or more vehicles are configured to perform pre-aiming control for road joints in response to receiving the second signal.

8. The method of claim 6, wherein, The method further includes sending the distance between the vehicle's location and the location, and / or the expected time for the vehicle to arrive at the location, together with the second signal, to the vehicle.

9. The method of claim 8, wherein, Performing pre-aiming control for road joints includes adjusting control parameters of the brake control unit, front axle motor, and / or rear axle motor before the vehicle passes the location.

10. A system for pre-aiming control of road joints, characterized in that, The system includes: one or more vehicles and a cloud platform communicatively coupled to the one or more vehicles; The one or more vehicles are configured to: identify road seams; and in response to identifying a road seam, send a first signal indicating the road seam along with the vehicle's current location to a cloud platform; The cloud platform is configured to: in response to receiving the first signal and the current position of the vehicle from one or more of the vehicles, mark the position of the road joint based on the current position; monitor the positioning and navigation information of the one or more vehicles; and when the positioning and navigation information of one or more of the vehicles indicates that the vehicle is expected to pass through the position, send a second signal to the vehicle to cause the vehicle to perform pre-aiming control for the road joint.

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