A method and apparatus for parking vehicles on roads with different slopes

Abstract

This invention provides a vehicle parking method and apparatus based on roads with different gradients. The method includes acquiring vehicle status information, including a vehicle speed signal; determining whether the vehicle is in a stopped state based on the vehicle speed signal; if the vehicle is in a stopped state, calculating the gradient value of the vehicle's current position based on a longitudinal acceleration sensor, and determining whether the gradient value is greater than a preset gradient value; if the gradient value is greater than the preset gradient value, immediately parking the vehicle through an electronic parking system. This application adds a PBC module to the vehicle stability control system, enabling the vehicle to be parked immediately through the electronic parking system when parking on a steep slope, preventing the vehicle from rolling away due to reduced braking force at the wheels.

Description

Technical Field

[0001] This invention relates to the field of electronic information technology, and in particular to a method and apparatus for parking vehicles on roads with different slopes. Background Technology

[0002] With the continuous development of vehicle electronics, more and more vehicles are now equipped with Electronic Stability Controller (ESC) and Electronic Park Brake (EPB) systems. The ESC's Auto Hold function works in conjunction with the EPB. Auto Hold uses hydraulic pressure to keep the vehicle in place, while the EPB applies parking brakes via the wheel-end brakes. When the vehicle is parked, Auto Hold uses hydraulic pressure to keep the vehicle stationary; after a set time, the EPB applies the parking brake.

[0003] In existing technologies, the vehicle is typically held in place initially by an Auto Hold hydraulic system, followed by EPB (Electronic Brake Brake) for a certain period. During the hydraulic hold period, leakage in the ESC's internal valve body and brake cooling can cause a decrease in braking force at the wheels, making the vehicle prone to rolling backward, especially on steep inclines, thus affecting safety. Furthermore, if the hydraulic hold system detects rolling backward, the ESC will actively apply pressure, resulting in significant noise and impacting comfort. Summary of the Invention

[0004] Based on this, the purpose of the present invention is to provide a vehicle parking method and device based on roads with different slopes, to solve the problem that in the prior art, when parking a vehicle, the ESC first performs Auto Hold hydraulic holding and then the EPB puts the vehicle in place. This causes the vehicle to roll away on a steep slope, and the braking force at the wheel end is easily reduced during the Auto Hold hydraulic holding period due to leakage in the internal valve body structure of the ESC and the cooling of the brake. This can easily lead to the vehicle rolling away and affect safety.

[0005] This invention provides a vehicle parking method based on roads with different slopes. The method is implemented through a vehicle parking device, which includes a vehicle stability control system and an electronic parking system. The vehicle stability control system includes a control unit and an Auto hold module, a PBC module, wheel speed sensors, and a longitudinal acceleration sensor, all connected to the control unit. The PBC module controls the electronic parking system and has PBC software. The wheel speed sensors are used to collect status signals of each wheel of the vehicle, and the longitudinal acceleration sensor is used to calculate the slope value of the vehicle's current position.

[0006] The method is specifically applied to a control unit, and the method includes:

[0007] When the Auto hold function is enabled, the vehicle status information is acquired, including the vehicle speed signal.

[0008] Determine whether the vehicle is in a stopped state based on the vehicle speed signal;

[0009] If the vehicle is stationary, the slope value of the vehicle's current position is calculated based on the longitudinal acceleration sensor, and it is determined whether the slope value is greater than a preset slope value.

[0010] If the slope value is greater than the preset slope value, the electronic parking system will be activated to park the vehicle immediately when the Auto hold function is triggered.

[0011] The above-mentioned vehicle parking method based on roads with different slopes, by adding a PBC module to the vehicle stability control system, allows the electronic parking system to be activated immediately when the Auto hold function is triggered when the vehicle needs to be parked on a slope with a large gradient. This avoids the need for the ESC to perform Auto hold hydraulic holding first, followed by the electronic parking brake system. This prevents the braking force at the wheels from decreasing due to leakage in the ESC's internal valve body structure or brake cooling during the Auto hold hydraulic holding process, which could easily cause the vehicle to roll away.

[0012] In addition, the vehicle parking method based on roads with different slopes according to the present invention may also have the following additional technical features:

[0013] Furthermore, after the step of immediately actuating the electronic parking system to park the vehicle when the Auto hold function is triggered, the method further includes:

[0014] The CAN network signal causes the instrument panel parking light to flash, display warning information, and emit an alarm sound, while simultaneously driving the electronic parking system's switch indicator light to illuminate and flash.

[0015] Furthermore, after determining whether the vehicle is in a stopped state based on the vehicle speed signal, the process further includes:

[0016] If the vehicle is not in a stopped state, the vehicle speed signal will continue to be monitored.

[0017] Furthermore, after the step of determining whether the slope value is greater than the preset slope value, the method further includes:

[0018] If the slope value is not greater than the preset slope value, the Auto hold module will keep the vehicle in place according to the existing parking strategy.

[0019] Furthermore, after the step of maintaining the vehicle in place according to the existing parking strategy by the Auto hold module, the following steps are included:

[0020] Obtain the holding time of the brake pressure provided by the Auto hold module;

[0021] Determine whether the holding time exceeds a preset time;

[0022] If the holding time exceeds the preset time, the vehicle will be parked using the electronic parking system.

[0023] Furthermore, if the slope value is greater than the preset slope value, the step of immediately activating the electronic parking system to park the vehicle when the Auto hold function is triggered includes:

[0024] The vehicle's lateral attitude is obtained based on the slope value, and it is determined whether the lateral attitude is a planar attitude.

[0025] If not, the lateral tilt angle of the vehicle is obtained based on the lateral posture, the braking force level of the vehicle is determined based on the lateral tilt angle, and the corresponding parking braking force is adjusted according to the force level. Attached Figure Description

[0026] Figure 1 This is a block diagram of the vehicle parking device in an embodiment of the present invention;

[0027] Figure 2 This is a flowchart of a vehicle parking method based on roads with different slopes in the first embodiment of the present invention;

[0028] Figure 3 This is a flowchart of a vehicle parking method based on roads with different slopes in the second embodiment of the present invention;

[0029] Figure 4 This is a flowchart of step S205 in the second embodiment of the present invention;

[0030] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0031] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Several embodiments of the invention are illustrated in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0033] To address the issue that existing parking solutions, which involve first using ESC (Electronic Stability Control) for Autohold hydraulic holding followed by EPB (Electronic Brake Braking) for parking on steep slopes, are prone to vehicle rollover due to reduced braking force at the wheels during Autohold pressure maintenance caused by factors such as leakage in the ESC's internal valve body and brake cooling, thus compromising safety, this application proposes a vehicle parking method and apparatus for roads with varying slopes. The method is implemented using a vehicle parking device, such as... Figure 1 As shown, the vehicle parking device includes:

[0034] The vehicle stability control system and electronic parking system are included. The vehicle stability control system includes a control unit and an Auto hold module, a PBC module, wheel speed sensors, and a longitudinal acceleration sensor, which are respectively connected to the control unit. The PBC module controls the electronic parking system and has PBC software (i.e., parking brake controller). The wheel speed sensors are used to collect the status signals of each wheel of the vehicle, and the longitudinal acceleration sensor is used to calculate the slope value of the current position of the vehicle.

[0035] Example 1

[0036] Please see Figure 2 The figure shows a vehicle parking method based on roads with different slopes according to the first embodiment of the present invention, the method including steps S101 to S104:

[0037] S101. Obtain vehicle status information.

[0038] When the Auto Hold function is activated, the system acquires vehicle status information, specifically the vehicle speed signal. When the driver applies the brakes to stop the vehicle, the ESC's Auto Hold function is triggered. Auto Hold first maintains braking pressure to keep the vehicle in place for a certain period, after which the EPB (Electronic Brake Brake) initiates parking, and Auto Hold disengages from the hydraulic holding state. During the Auto Hold hydraulic holding period, if vehicle roll is detected, the ESC actively applies pressure to increase the braking pressure on the wheels to prevent roll. However, the active pressure application by the ESC generates significant noise, affecting comfort. Therefore, adjustments to the existing parking mechanism are needed to avoid safety and comfort issues.

[0039] S102. Determine whether the vehicle is stationary based on the vehicle speed signal.

[0040] If the vehicle is stationary, the slope value of the vehicle's current position is calculated based on the longitudinal acceleration sensor, and step S103 is executed.

[0041] S103. Determine whether the slope value is greater than the preset slope value.

[0042] To properly configure vehicle braking conditions, it is necessary to define each braking scenario. This means braking must be performed according to different scenarios to maximize the vehicle's braking performance, ensuring braking safety while also improving braking and mechanical performance. In this application, a slope exceeding a preset slope value can be defined as a significant slope.

[0043] If the slope value is greater than the preset slope value, then proceed to step S104;

[0044] S104. When the Auto hold function is triggered, the electronic parking system is immediately activated to park the vehicle.

[0045] In summary, the vehicle parking method based on roads with different slopes in the above embodiments of the present invention, by adding a PBC module to the vehicle stability control system, enables the vehicle to be parked immediately by the electronic parking system when the Auto hold function is triggered when the vehicle needs to be parked on a slope with a large gradient. This avoids the need for the ESC to perform Auto hold hydraulic holding first, followed by the electronic parking brake system, thereby preventing the braking force at the wheel end from decreasing due to leakage in the internal valve body structure of the ESC, brake temperature cooling, etc. during the Auto hold pressure holding process, which could easily cause the vehicle to roll away.

[0046] Example 2

[0047] Please see Figure 3The figure shows a vehicle parking method based on roads with different slopes according to the second embodiment of the present invention, the method including steps S201 to S207:

[0048] S201. Obtain vehicle status information.

[0049] In this application, the status information includes the vehicle speed signal. In this application, the ESC (Vehicle Stability Control) module integrates the PBC software from the EPB (Electronic Parking System). The ESC optimizes the control strategy by identifying the slope value of the vehicle's location and adopting different control strategies for different slopes, effectively preventing the vehicle from rolling back on steep inclines and improving comfort.

[0050] Furthermore, after the Auto hold function is activated by the switch, when the driver applies the brakes to stop the vehicle, the ESC determines whether the vehicle has stopped based on the signals collected by the wheel speed sensors of each wheel. After determining that the vehicle is stopped, the ESC calculates the slope value of the vehicle's current position based on the longitudinal acceleration sensor (G-sensor) and selects different control schemes for different slopes.

[0051] S202. Determine whether the vehicle is stationary based on the vehicle speed signal.

[0052] If the vehicle is not in a stopped state, proceed to step S203;

[0053] If the vehicle is stationary, the slope value of the vehicle's current position is calculated based on the longitudinal acceleration sensor, and step S204 is executed.

[0054] S203. Continue to monitor vehicle speed signals.

[0055] S204. Determine whether the slope value is greater than the preset slope value.

[0056] In this embodiment, when the slope value is small and does not exceed the set value (e.g., 30%), Auto hold performs hydraulic holding. After the hydraulic holding time reaches the set value, EPB (Electronic Parking System) performs parking.

[0057] When the gradient is too steep, exceeding the set value (e.g., 30%), to prevent the vehicle from rolling back due to reduced braking force caused by ESC valve body leakage or brake cooling, the ESC module, upon triggering the Auto hold hydraulic hold, immediately activates the EPB (Electronic Parking Brake) system to hold the vehicle. This is achieved by sending a CAN network signal to the instrument panel parking light to flash, displaying corresponding warning information, and emitting an alarm sound. Simultaneously, the EPB (Electronic Parking Brake) switch indicator light flashes. These visual and auditory signals alert the driver to the excessive gradient and the risk of rolling back.

[0058] If the slope value is not greater than the preset slope value, then proceed to step S205;

[0059] If the slope value is greater than the preset slope value, then proceed to step S206;

[0060] S205. The Auto hold module keeps the vehicle in place according to the existing parking strategy.

[0061] As a concrete example, such as Figure 4 As shown, step S205 includes steps S2051-S2053:

[0062] S2051. Obtain the holding time of the braking pressure provided by the Auto hold module.

[0063] S2052. Determine whether the holding time exceeds the preset time.

[0064] If the holding time exceeds the preset time, then proceed to step S2053;

[0065] S2053. Parking is performed using the electronic parking system.

[0066] Specifically, the preset time can be 1 minute, 3 minutes, etc., and the specific time can be determined according to the actual situation. When the holding time exceeds the preset time, it is considered that this is not a temporary parking and the vehicle parking system needs to proceed to the next step to ensure that the vehicle can be parked safely and stably.

[0067] S206. When the Auto hold function is triggered, the electronic parking system is immediately activated to park the vehicle.

[0068] This invention addresses the issue of vehicle rollback during Auto Hold on steep inclines. It optimizes the control strategy by using a slope sensor to identify the current incline and employing different control methods for different slopes. Specifically: when the slope is gentle, the existing strategy first applies Auto Hold hydraulic pressure, and after a set time, the EPB (Electronic Power Brake) initiates parking. When the slope is steep, the EPB initiates parking immediately upon triggering Auto Hold hydraulic pressure, alerting the driver via instrument panel indicators, audio, and power indicator lights to the excessive incline and potential rollback risk. This effectively prevents rollback and avoids the significant noise generated by the ESC (Electronic Stability Control) actively applying pressure due to vehicle rollback, thus improving comfort.

[0069] As a specific example, steps S205 and S206 specifically include:

[0070] The vehicle's lateral attitude is obtained based on the slope value, and it is determined whether the lateral attitude is a planar attitude.

[0071] If the lateral attitude is not planar, meaning the slope where the vehicle is currently stationary is tilted in the lateral direction, then if we assume the vehicle is positioned in a spatial coordinate system with the vehicle's center as the origin, the vehicle is tilted not only in the z-axis direction but also in the x-axis direction. In this embodiment, the lateral attitude is the vehicle's attitude in the x-axis direction of the spatial coordinate system. To further determine the vehicle's parking attitude, the lateral tilt angle of the vehicle is obtained based on the lateral attitude, the vehicle's braking force level is determined based on the lateral tilt angle, and the corresponding hydraulic holding force and parking braking force are adjusted based on the force level.

[0072] If the vehicle is also tilted in the x-direction, the force on each wheel will be different. Taking the direction of the vehicle's front as positive, from the driver's perspective, the vehicle includes the left front wheel, right front wheel, left rear wheel, and right rear wheel. The following example illustrates how the braking force on each wheel differs when the vehicle is tilted laterally:

[0073] When a vehicle is on a slope with a lateral inclination, causing the right front wheel to be suspended in the air, the vehicle's weight distribution has shifted from its original position due to the severe tilt. Applying the same braking force to each wheel according to the existing distribution strategy is unreasonable and unnecessary. Furthermore, each braking action will cause wear, and braking devices have a limited lifespan. Therefore, it is essential to determine the vehicle's braking force level based on the lateral tilt angle and adjust the corresponding hydraulic holding force and parking brake force accordingly to improve braking performance and reduce wear.

[0074] Specifically, when a vehicle is on a slope with a lateral inclination, causing its right front wheel to be suspended in the air, the right front wheel is not in contact with the slope. However, other structures on the right front of the vehicle are in contact with the slope, such as the chassis located at the right front. To ensure the vehicle's force balance, the left front wheel, left rear wheel, and right rear wheel are all in contact with the slope. In this case, even if braking force is applied to the right front wheel, it will not affect the overall parking effect of the vehicle, and the braking force level of the right front wheel is the lowest. However, because the right front wheel is suspended in the air, the force on the left front wheel and right rear wheel is much greater than the force when the slope is not lateral. In this scenario, the left front wheel and right rear wheel are the main force points, so to ensure safe and stable parking, the braking force level of the left front wheel and right rear wheel is the highest. As for the left rear wheel, because the vehicle body is tilted to the right front, the left rear of the vehicle body is lifted up, so the braking force level of the left rear wheel is in the middle. Therefore, the hydraulic holding force and parking brake force applied to the vehicle should be highest for the left front wheel and the right rear wheel, followed by the left rear wheel, and lowest for the right front wheel. Distributing the braking force in this order avoids wasting resources, reduces wear on the braking system, and extends its service life.

[0075] In another alternative embodiment, similarly, when the vehicle's right front wheel sinks into a pit and contacts the bottom, the braking force level of the right front wheel is the highest, followed by the braking force level of the left front wheel and the right rear wheel, with the braking force level of the left rear wheel being the lowest. Therefore, the hydraulic holding force and parking brake force applied to the vehicle should also be highest for the right front wheel, followed by the left front wheel and the right rear wheel, with the left rear wheel being the lowest.

[0076] S207: The instrument parking light flashes and displays warning information and sounds an alarm via CAN network signal, while simultaneously driving the electronic parking system switch indicator light to light up and flash.

[0077] It should be noted that the method provided in the second embodiment of the present invention has the same implementation principle and some technical effects as the first embodiment. For the sake of brevity, any parts not mentioned in this embodiment can be referred to the corresponding content in the first embodiment.

[0078] In summary, the vehicle parking method based on roads with different slopes in the above embodiments of the present invention, by adding a PBC module to the vehicle stability control system, enables the vehicle to be parked immediately through the electronic parking system when the vehicle needs to be parked on a slope with a large gradient. This avoids the situation where the ESC performs Auto Hold hydraulic holding first, which can lead to a decrease in braking force at the wheel end due to leakage in the internal valve body structure of the ESC, brake temperature cooling, etc., which can easily cause the vehicle to roll away.

[0079] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0080] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0081] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A vehicle parking method based on roads with different slopes, characterized in that, The method is implemented through a vehicle parking device, which includes a vehicle stability control system and an electronic parking system. The vehicle stability control system includes a control unit and an Auto hold module, a PBC module, wheel speed sensors, and a longitudinal acceleration sensor, which are respectively connected to the control unit. The PBC module controls the electronic parking system and has PBC software. The wheel speed sensors are used to collect the status signals of each wheel of the vehicle, and the longitudinal acceleration sensor is used to calculate the slope value of the current position of the vehicle. The method is specifically applied to a control unit, and the method includes: When the Auto hold function is enabled, the vehicle status information is acquired, including the vehicle speed signal. Determine whether the vehicle is in a stopped state based on the vehicle speed signal; If the vehicle is stationary, the slope value of the vehicle's current position is calculated based on the longitudinal acceleration sensor, and it is determined whether the slope value is greater than a preset slope value. If the slope value is greater than the preset slope value, the electronic parking system will be immediately activated to park the vehicle when the Auto hold function is triggered. The step of immediately activating the electronic parking system to park the vehicle when the Auto hold function is triggered if the slope value is greater than the preset slope value includes: The vehicle's lateral attitude is obtained based on the slope value, and it is determined whether the lateral attitude is a planar attitude. If not, the lateral tilt angle of the vehicle is obtained based on the lateral posture, the braking force level of the vehicle is determined based on the lateral tilt angle, and the corresponding parking braking force is adjusted based on the force level. The steps of obtaining the vehicle's lateral tilt angle based on the lateral posture, determining the vehicle's braking force level based on the lateral tilt angle, and adjusting the corresponding parking braking force based on the force level include: When a vehicle is on a slope with a lateral inclination that causes the right front wheel to be suspended in the air, the hydraulic holding force and parking brake force applied to the vehicle are highest on the left front wheel and the right rear wheel, followed by the left rear wheel, and lowest on the right front wheel. When the right front wheel of a vehicle sinks into a pit and contacts the bottom of the pit, the hydraulic holding force and parking brake force applied to the vehicle are highest at the right front wheel, followed by the left front wheel and the right rear wheel, and lowest at the left rear wheel.

2. The vehicle parking method based on roads with different slopes according to claim 1, characterized in that, Following the step of immediately actuating the electronic parking system to park the vehicle when the Autohold function is triggered, the following steps are also included: The CAN network signal causes the instrument panel parking light to flash, display warning information, and emit an alarm sound, while simultaneously driving the electronic parking system's switch indicator light to illuminate and flash.

3. The vehicle parking method based on roads with different slopes according to claim 1, characterized in that, Following the step of determining whether the vehicle is stationary based on the vehicle speed signal, the following further steps are also included: If the vehicle is not in a stopped state, the vehicle speed signal will continue to be monitored.

4. The vehicle parking method based on roads with different slopes according to claim 1, characterized in that, After determining whether the slope value is greater than the preset slope value, the method further includes: If the slope value is not greater than the preset slope value, the Auto hold module will keep the vehicle in place according to the existing parking strategy.

5. The vehicle parking method based on roads with different slopes according to claim 4, characterized in that, After the Auto hold module maintains the vehicle in place according to the existing parking strategy, the following steps are included: Obtain the holding time of the brake pressure provided by the Auto hold module; Determine whether the holding time exceeds a preset time; If the holding time exceeds the preset time, the vehicle will be parked using the electronic parking system.

6. The vehicle parking method based on roads with different slopes according to claim 1, characterized in that, If the slope value is greater than the preset slope value, the steps for immediately activating the electronic parking system to park the vehicle when the Auto hold function is triggered include: The vehicle's lateral attitude is obtained based on the slope value, and it is determined whether the lateral attitude is a planar attitude. If not, the lateral tilt angle of the vehicle is obtained based on the lateral posture, the braking force level of the vehicle is determined based on the lateral tilt angle, and the corresponding parking braking force is adjusted according to the force level.

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