A control method and system of intelligent wiper and a car

Abstract

The application discloses a kind of intelligent wiper control method and system, car, wherein method includes obtaining wiper switch signal and vehicle information on vehicle CAN bus;Based on wiper switch signal, it is judged whether to start the automatic control of wiper;After judging to start the automatic control of wiper, the theoretical wiping speed of wiper is calculated based on the vehicle information read on vehicle CAN bus, and the wiper motor is controlled according to the theoretical wiping speed of wiper.The application has the advantages that the rain sensor is cancelled, the purpose of low-cost wiper control is realized, the control of wiper is realized through logic control, and the cost of wiper control is saved.

Description

Technical Field

[0001] This invention relates to the field of automotive wiper control, and particularly to a control method and system for intelligent wipers, and an automobile. Background Technology

[0002] Automatic wiper technology is driven by a triple force: policy, market, and industrial upgrading. Global safety and environmental regulations are driving demand for high-performance, low-energy wipers; the popularization of new energy vehicles and high-end models is increasing the penetration rate of smart wipers and releasing the potential of emerging markets; and under the trend of intelligentization, wipers, as a component of ADAS, are deeply integrated with functions such as autonomous driving and vehicle speed linkage, accelerating technological iteration.

[0003] Current technology is based on sensor fusion and intelligent algorithms: rain sensors (infrared / capacitive) are combined with environmental data (camera, radar) to achieve multimodal perception and control the speed of the windshield wipers.

[0004] Existing wiper control technology relies on the addition of hardware sensors, such as rain sensors. After the automatic wiper function is turned on, the wiper speed is controlled based on the rainfall signal collected by the rain sensor. This solution is not suitable for cost-sensitive vehicles. Due to the limitation of hardware cost control, the industry is looking for ways to control wipers without rain sensors. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a smart wiper control method and system for automobiles. By eliminating the rain sensor, the automatic wiper speed is controlled by logic control, effectively meeting the cost requirements of wiper control.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a control method for intelligent windshield wipers, comprising acquiring windshield wiper switch signals and vehicle information on the vehicle CAN bus; determining whether to activate automatic windshield wiper control based on the windshield wiper switch signals; after determining that automatic windshield wiper control is activated, calculating the theoretical wiping speed of the windshield wipers based on the vehicle information read from the vehicle CAN bus, and controlling the windshield wiper motor according to the theoretical wiping speed of the windshield wipers.

[0007] The system collects the wiper motor's wiper return signal and calculates the actual wiper speed based on the signal. The wiper speed setting is then adjusted based on the real-time calculated theoretical and actual wiper speeds.

[0008] The vehicle information on the CAN bus includes the ignition switch status signal and the vehicle speed signal; the automatic control of the wipers is determined based on the wiper switch signal and the ignition switch status signal; when the ignition switch is in the ON position and the wiper switch is in the INT position and a set time threshold is continuously set, the automatic control of the wipers is determined to be activated.

[0009] The theoretical wiping speed Vm of the windshield wipers is calculated based on the vehicle speed signal read from the vehicle's CAN bus; the calculation formula is: Vm=K*Vv+C; Where K is a proportionality constant; C is the number of scraping times constant; and Vv is the vehicle speed.

[0010] The wiper return signal is acquired and the number of times it returns to its original position per unit time is calculated as the actual wiping speed of the wiper; the wiper return signal is acquired through the output position signal of the wiper motor.

[0011] The actual wiping speed Vs and the theoretical wiping speed Vm of the windshield wipers are controlled as follows: When Vm≤Vs, control the windshield wipers to run intermittently at low speed; When Vm > Vs + T, control the windshield wipers to operate intermittently at high speed. When Vs < Vm ≤ Vs + T, the windshield wipers maintain the current setting and operate intermittently. Where T is a constant threshold.

[0012] After the automatic control of the wipers is activated, the actual wiping speed is periodically calculated and compared with the current theoretical wiping speed to adjust the current wiper control level.

[0013] If the ignition switch is returned to the OFF position or the wiper INT switch signal is invalid, the automatic wiper control function is deactivated.

[0014] A smart windshield wiper control system includes an on-board controller; the on-board controller is connected to a wiper switch and a vehicle CAN bus to obtain wiper switch signals and vehicle information on the vehicle CAN bus; the output of the on-board controller is connected to a wiper motor to control the operating status and speed of the wiper motor; the on-board controller obtains a wiper return signal output by the wiper motor; the on-board controller integrates control software to implement the method.

[0015] An automobile that uses the method to control windshield wipers; or the automobile includes the control system described above.

[0016] The advantages of this invention are: it eliminates the rain sensor, achieving low-cost wiper control; and it achieves wiper control through logic control, saving wiper control costs. Attached Figure Description

[0017] The following is a brief explanation of the contents of each of the accompanying drawings and the markings in the drawings: Figure 1 This is a schematic diagram of the control system of the present invention; Figure 2This is a flowchart illustrating the control method of the present invention. Detailed Implementation

[0018] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and the description of the preferred embodiments.

[0019] The main purpose of this embodiment is to eliminate the rain sensor and achieve wiper speed control. The wiper speed is controlled by vehicle speed, wiper switch and return signal to meet the user's purpose of automatic wiper control in rainy weather. This achieves a low-cost wiper control strategy, which is convenient for cost control and suitable for low-cost vehicle models.

[0020] like Figure 1-2 The diagram shown illustrates the system structure and control strategy of the wiper control scheme in this embodiment. In a smart wiper control method of this embodiment, the method includes acquiring a wiper switch signal and vehicle information on the vehicle's CAN bus; determining whether to activate automatic wiper control based on the wiper switch signal; and after determining that automatic wiper control is activated, calculating the theoretical wiping speed based on the vehicle information read from the vehicle's CAN bus, and controlling the wiper motor according to the theoretical wiping speed.

[0021] The automatic wiper control function is activated based on the wiper switch signal and the vehicle's ON signal. When the ignition switch is ON and the wiper switch is INT for a set time threshold, automatic wiper control is activated. An ON ignition signal indicates the vehicle is running, while the INT signal indicates the wipers are in automatic mode. To avoid interference or fluctuations, the INT signal must remain valid for a set time before activating automatic wiper control, preventing erroneous activation. This valid time threshold can be calibrated; this solution uses 50ms as the threshold standard.

[0022] In this embodiment, when the ignition switch is returned to the OFF position or the wiper INT switch signal is invalid, it is determined that the automatic wiper control function is exited, the automatic control is ended, and the wipers are stopped.

[0023] In this embodiment, after the automatic control function is activated, the theoretical wiper wiping speed is first calculated, and then the vehicle wipers are controlled according to the theoretical wiping speed to control the operation of the wipers. After the wipers are running, the wiper motor's wiper return signal is collected, and the actual wiper wiping speed is calculated based on the wiper return signal. The control of the wiper speed level is adjusted based on the real-time calculated theoretical wiper wiping speed and the actual wiper wiping speed.

[0024] Because the theoretical wiping speed is a calculated value, after using the theoretical wiping speed for control, it is necessary to compare the theoretical and actual operating speeds to fine-tune the wiper speed. Generally, automatic wiper controls also have multiple speed settings, which can be adjusted based on the relationship between the theoretical and actual speeds.

[0025] In this embodiment, the vehicle information on the CAN bus includes the ignition switch status signal and the vehicle speed signal; the automatic control of the wipers is determined based on the wiper switch signal and the ignition switch status signal; and the theoretical wiping speed is calculated based on the vehicle speed.

[0026] In this embodiment, the theoretical wiping speed Vm of the windshield wipers is calculated based on the vehicle speed signal read from the vehicle's CAN bus; the calculation formula is: Vm=K*Vv+C; Where K is a proportionality constant, C is the number of scraping cycles constant, and Vv is the vehicle speed. The theoretical scraping speed is the scraping speed that meets the basic requirements of the vehicle. It is calculated by relating it to the vehicle speed. This scraping speed can actually meet the needs of the vehicle at different speeds. For example, at low speeds, the number of scraping cycles provided by the scraping constant can meet the requirements of low-speed driving. Because the lower the vehicle speed, the slower the forward movement, the lower the requirements for forward visibility and the risk of collision. Therefore, the scraping speed can be lower. At higher speeds, the distance traveled per unit time is greater. At this time, it is necessary to ensure the scraping speed as much as possible. Therefore, it is reasonable to calculate the theoretical scraping speed through speed. The specific constant can be calibrated through experiments.

[0027] In this embodiment, the constant C is calibrated to be around 20 times / min, and k is around 0.6. These values ​​can be fine-tuned. Taking C = 20 and K = 0.6 as an example, when the vehicle speed is 1 km / h, the theoretical wiping speed is 20.6 times per minute, approximately once every three seconds. At this speed of 1 km / h, the wiping speed clearly meets the requirements. When the vehicle speed is 10 km / h, the theoretical wiping speed is 26 times per minute. Clearly, at 10 km / h, the wiping speed of approximately once every two seconds also meets the requirements. At 50 km / h, a common speed in urban areas, the calculated theoretical speed is 50 times per minute. At this speed, the wiping speed is 50, which is sufficient even with heavy rainfall. Therefore, this solution calculates the theoretical wiping speed based on vehicle speed, meeting the user's basic requirements.

[0028] After controlling the vehicle using the theoretical wiping speed, the speed is adjusted by comparing the theoretical and actual wiping speeds. The wiper return signal is acquired, and the number of returns per unit time is calculated as the actual wiping speed. The wiper return signal is obtained through the output position signal of the wiper motor. Once the actual wiping speed corresponding to the return signal is obtained, the real-time theoretical vehicle speed is immediately calculated based on the current vehicle speed. This real-time theoretical wiping speed is compared with the previously calculated actual wiping speed to adjust the current wiper control speed and level. Generally, if the vehicle speed remains constant, the wiping speed also remains constant, and the theoretical and actual wiping speeds remain within the same range. When the vehicle speed changes, the calculated theoretical value changes, while the statistically calculated actual value is from the previous moment. The wiper speed level is adjusted by comparing the previously calculated actual wiping speed with the current theoretical speed value, as detailed below: The actual wiping speed Vs and the theoretical wiping speed Vm of the windshield wipers are controlled as follows: When Vm≤Vs, control the windshield wipers to run intermittently at low speed; When Vm > Vs + T, control the windshield wipers to operate intermittently at high speed. When Vs < Vm ≤ Vs + T, the windshield wipers maintain the current setting and operate intermittently. Where T is a constant threshold, and in this embodiment, T is set to 3.

[0029] In this embodiment, after the automatic control of the wipers is activated, the actual wiping speed of the wipers is periodically calculated and compared with the current theoretical wiping speed to adjust the current wiper control level. At the beginning of the operation, the theoretical value is used for control, and then the control of the wipers is adjusted according to the relationship between the actual value and the theoretical value to meet the user's needs for the wiper working speed.

[0030] like Figure 1 As shown, this embodiment eliminates the rain sensor, resulting in an intelligent wiper control system, including an onboard controller. The onboard controller is connected to the wiper switch and the vehicle CAN bus to obtain wiper switch signals and vehicle information from the CAN bus. The output of the onboard controller is connected to the wiper motor to control its operating state and speed. The onboard controller also acquires the wiper return signal output by the wiper motor. The onboard controller integrates control software that implements the method described in the above embodiment to control the wiper speed. In this embodiment, the onboard controller is implemented using a BCM (Balanced Controller Management) system.

[0031] This embodiment also provides a car that controls the windshield wipers using the method described above; or the car that controls the windshield wipers using the control system described above.

[0032] The simplified intelligent wiper function provided in this embodiment requires acquiring accurate vehicle speed information from the VCU via a CAN network, acquiring wiper switch position information via a hard-wired interface, and acquiring vehicle ignition switch information via a hard-wired structure. Then, intelligent wiper control is achieved through a pure software logic algorithm. This algorithm relies on a wiper control system based on the vehicle's body controller, and its basic principle is as follows: Figure 1 As shown, the body controller performs logical operations on the control algorithm by collecting the wiper mode signal from the combination switch, the ignition switch status signal, the vehicle speed signal from the CAN bus, and the wiper return signal, and then controls the wiper motor to perform corresponding actions. Its working process is as follows: 1. First, the ignition switch of the whole vehicle needs to be switched from the OFF position to the ON position to test whether the power supply of the whole vehicle is in the ON position and the whole vehicle is powered on at low voltage. Only after the BCM receives this power can it work normally. 2. The wiper switch needs to be adjusted from other positions to the INT position so that the vehicle controller can accurately collect the INT signal from the wiper switch. 3. Other controllers on the vehicle, such as ABS and VCU, need to send vehicle speed information to the CAN bus network. At this time, the body controller can collect vehicle speed-related information from the CAN network bus. 4. The wiper control port of the body controller needs to be directly connected to the wiper motor so that the body controller can drive the wiper motor normally. At the same time, the return signal in the wiper motor needs to be returned and connected to the body controller so that the body controller can know whether the wiper is in the initial position.

[0033] 5. After the body controller receives all the information from 1 to 4 above, the body control system can run this simple intelligent wiper control algorithm normally. The algorithm runs as follows.

[0034] 6. Triggering method of this control algorithm: The ignition switch is in the ON position and the wiper INT switch signal is valid for ≥50ms.

[0035] This control algorithm can be turned off when the ignition switch is returned to the OFF position or the wiper INT switch signal is invalid.

[0036] This control algorithm implements intelligent control of the wiper wiping speed, which should satisfy the following formula: Vm=K*Vv+C Vm: Theoretical wiping speed of windshield wipers (strokes / minute) Vv: Vehicle speed (km / h) C: Scraping speed constant (times / minute) K: Proportional constant C=20 (times / minute), K=0.6 (These data will be adjusted based on actual test results). Meanwhile, the BCM calculates the actual wiping speed Vs (wipers per minute) automatically based on the wiper return signal. When Vm≤Vs, the windshield wipers operate intermittently at low speed. When Vm > Vs + 3, the windshield wipers operate intermittently at high speed. When Vs < Vm ≤ Vs + 3, the wipers maintain the current speed setting (high or low) and operate intermittently.

[0037] This simplified intelligent wiper control algorithm reuses the vehicle's existing speed and switch signals, eliminating the need for high-cost rain sensors. It achieves intelligent adjustment of the wiper motor speed through speed segment mapping and dynamic correction logic, combining significant cost advantages with high reliability (dual-mode control + redundant design). It provides an efficient, safe, and easily integrated intelligent solution for economy vehicles and the aftermarket.

[0038] Obviously, the specific implementation of this invention is not limited to the above-described methods. Any non-substantial improvements made using the inventive concept and technical solution of this invention are within the protection scope of this invention.

Claims

1. A method for controlling intelligent windshield wipers, characterized in that: This includes acquiring wiper switch signals and vehicle information on the vehicle's CAN bus; determining whether to activate the wipers based on the wiper switch signals; after determining that the wipers should be activated, calculating the theoretical wiping speed based on the vehicle information read from the vehicle's CAN bus, and controlling the wiper motor according to the theoretical wiping speed; and acquiring the wiper motor's wiper return signal and calculating the actual wiping speed based on the wiper return signal. The wiper speed setting is controlled by adjusting the theoretical and actual wiper wiping speeds based on real-time calculations. Vehicle information on the CAN bus includes ignition switch status signals and vehicle speed signals. Automatic wiper control is activated based on the wiper switch signals and ignition switch status signals. When the ignition switch is in the ON position and the wiper switch is in the INT position for a set time threshold, automatic wiper control is activated. The current theoretical wiper wiping speed Vm is calculated based on the vehicle speed signal read from the vehicle's CAN bus; the calculation formula is: Vm = K * Vv + C. Where K is a proportional constant; C is the number of wiping cycles constant; and Vv is the vehicle speed. The wiper return signal is acquired, and the number of returns per unit time is calculated as the actual wiper wiping speed. The wiper return signal is obtained through the output position signal of the wiper motor. The actual wiper speed Vs and the theoretical wiper speed Vm are controlled as follows: When Vm≤Vs, control the windshield wipers to run intermittently at low speed; When Vm > Vs + T, control the windshield wipers to operate intermittently at high speed. When Vs < Vm ≤ Vs + T, the windshield wipers maintain the current setting and operate intermittently. Where T is a constant threshold; after the automatic control of the wipers is started, the actual wiping speed of the wipers is periodically calculated and compared with the current theoretical wiping speed to adjust and control the current wiper control level.

2. The intelligent wiper control method as described in claim 1, characterized in that: If the ignition switch is returned to the OFF position or the wiper INT switch signal is invalid, the automatic wiper control function is deactivated.

3. A control system for an intelligent windshield wiper, characterized in that: The system includes an on-board controller; the on-board controller is connected to the wiper switch and the vehicle CAN bus to obtain wiper switch signals and vehicle information on the vehicle CAN bus; the output of the on-board controller is connected to the wiper motor to control the operating status and speed of the wiper motor; the on-board controller obtains the wiper return signal output by the wiper motor; the on-board controller integrates control software that implements the method as described in claim 1 or 2.

4. A car, characterized in that: The vehicle uses the method described in claim 1 or 2 to control the windshield wipers; or the vehicle includes the control system described in claim 3.

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