Automobile automatic windshield wiper control system and method

Abstract

The present invention discloses an automatic windshield wiper control system and method for an automobile. The system includes an automatic wiper switch, configured to send an on-state signal to a rain detection module upon being turned on by the driver; a vehicle speed detection module, configured to detect vehicle speed in real time and send the signal to the rain detection module; the rain detection module, configured to obtain infrared light reception values ​​in real time upon receiving the on-state signal, determine rainfall based on the infrared light reception values ​​and a wiper position signal, determine the degree of wiper action based on the rainfall and vehicle speed, and send a wiper request to a control module; a control module, configured to send a wiper signal to a wiper motor upon receiving the wiper request; and a wiper motor, configured to control a wiper blade to perform a wiper action upon receiving the wiper signal and to feed back a wiper position signal to the rain detection module. By optimizing the rainfall calculation logic, the present invention improves the accuracy and reliability of automatic windshield wipers.

Description

Technical Field

[0001] The invention belongs to the technical field of automobile control, and in particular relates to an automobile automatic windshield wiper control system and method. Background Art

[0002] With the improvement of living standards and the development of automotive technology, people are increasingly demanding intelligent vehicles. Automatic wipers, as an intelligent automotive feature, can proactively sense the amount of rain and initiate wiper movements and stops, reducing frequent manual operation and improving driving convenience and comfort for passengers. As a result, they are being installed on an increasing number of vehicles. With the widespread adoption of automatic wipers, the requirements for their accuracy and reliability are becoming increasingly stringent. Automatic wipers use a light-based rain sensor located on the inside of the vehicle's windshield to calculate rainfall and issue a wiper request. The accuracy of automatic wipers is directly determined by the accuracy of the light-based rain sensor's rainfall calculations. However, this accuracy is affected by factors such as glass cleanliness, residual water film on the wiper arm, water film created when the wiper arm passes the sensor, and light fluctuations. Furthermore, the light-based rain sensor is constantly computing, placing a heavy computational load and impacting efficiency and reliability. Summary of the Invention

[0003] The purpose of the present invention is to solve the deficiencies in the above-mentioned background technology and to provide an automobile automatic windshield wiper control system and method.

[0004] The technical solution adopted by the present invention is: an automobile automatic wiper control system, comprising

[0005] Automatic wiper switch, used to send an on signal to the rain detection module after the driver turns it on;

[0006] Vehicle speed detection module, used to detect vehicle speed in real time and send it to rainfall detection module;

[0007] The rain detection module is used to obtain the infrared light reception value in real time after receiving the start signal, determine the rainfall based on the infrared light reception value and the wiper position signal, determine the degree of wiper wiping action based on the rainfall and vehicle speed, and send a wipe request to the control module;

[0008] A control module, configured to send a wipe signal to the wiper motor after receiving a wipe request;

[0009] The wiper motor is used to control the wiper blade to perform the wiping action after receiving the wiping signal, and is used to feed back the wiper position signal to the rain detection module.

[0010] Furthermore, the rainfall determined by the rain detection module includes initial rainfall and process rainfall. The rain detection module determines the initial rainfall based on the initial infrared light reception value; the rain detection module collects the infrared light reception value in the set time period according to the wiper position, calculates the infrared light average value based on the infrared light reception value, and determines the process rainfall by the sum of the infrared light average value and the minimum value of the infrared light loss value during this wiping process.

[0011] Furthermore, the process of the wiper performing a wiping operation includes upward wiping and downward wiping, the upward wiping is wiping from the downward stop position to the upward stop position, and the downward wiping is wiping from the upper stop position to the lower stop position, and the set time period includes a first time period from the initial moment when the wiper is located at the lower stop position to moment T1 during upward wiping and a second time period from moment T2 to the end moment when the wiper is located at the lower stop position during downward wiping.

[0012] A method for controlling an automatic windshield wiper of an automobile comprises the following steps:

[0013] Step 1: After the automatic wiper switch is turned on, obtain the vehicle speed and infrared light reception value in real time;

[0014] Step 2: determining an initial rainfall amount based on the initial infrared light reception value, determining the degree of wiper wiping action based on the initial rainfall amount and the vehicle speed, and controlling the wiper to perform a first wipe based on the degree of wiper wiping action;

[0015] Step 3: While the wipers are wiping, the wiper position is detected, infrared light reception values ​​are collected during a set period based on the wiper position, an average infrared light value is calculated based on the infrared light reception values, and the process rainfall is determined by the sum of the average infrared light value and the minimum infrared light loss value during the current wiping process. The degree of wiper wiping action is determined based on the process rainfall and vehicle speed, and the wipers are controlled to perform the next wipe according to the degree of wiping action;

[0016] Step 4: Repeat step 3 until the wiper switch is turned off.

[0017] Furthermore, the process of the wiper performing a wiping operation includes upward wiping and downward wiping, the upward wiping is wiping from the downward stop position to the upward stop position, and the downward wiping is wiping from the upper stop position to the lower stop position, and the set time period includes a first time period from the initial moment when the wiper is located at the lower stop position to moment T1 during upward wiping and a second time period from moment T2 to the end moment when the wiper is located at the lower stop position during downward wiping.

[0018] Furthermore, the wiper action degree of the wiper is any one of no action, intermittent wiping, low-speed wiping, and high-speed wiping, and the travel speed of the wiper blade of the intermittent wiping, low-speed wiping, and high-speed wiping increases in sequence.

[0019] Furthermore, when any of the following conditions is met, the wiper wiping action level is determined to be inactive:

[0020] a. 0<V≤V1 and M≤γ;

[0021] b. V1<V≤V2 and M≤β;

[0022] c. V>V2 and M≤α;

[0023] Wherein, V is the vehicle speed; M is the initial rainfall or process rainfall; V1 and V2 are the first set value and the second set value of the vehicle speed, respectively, and V1<V2; α, β, and γ are the first threshold, second threshold, and third threshold of rainfall, respectively, and α<β<γ.

[0024] Furthermore, when any of the following conditions is met, the wiping action of the wiper is determined to be intermittent wiping:

[0025] a, 0<V≤V1 and γ<M≤δ;

[0026] b. V1<V≤V2 and β<M≤γ;

[0027] c. V>V2 and α<M≤β;

[0028] Wherein, V is the vehicle speed; M is the initial rainfall or process rainfall; V1 and V2 are the first set value and the second set value of the vehicle speed, respectively, and V1<V2; α, β, γ, and δ are the first threshold, second threshold, third threshold, and fourth threshold of rainfall, respectively; α<β<γ<δ.

[0029] Furthermore, when any of the following conditions is met, the wiping action level of the wiper is determined to be low-speed wiping:

[0030] a, 0<V≤V1 and δ<M≤ε;

[0031] b. V1<V≤V2 and γ<M≤δ;

[0032] c. V>V2 and β<M≤γ;

[0033] Wherein, V is the vehicle speed; M is the initial rainfall or process rainfall; V1 and V2 are the first set value and the second set value of the vehicle speed, respectively, and V1<V2; β, γ, δ, and ε are the second threshold, third threshold, fourth threshold, and fifth threshold of rainfall, respectively; β<γ<δ<ε.

[0034] Furthermore, when any of the following conditions is met, the wiping action of the wiper is determined to be high-speed wiping:

[0035] a. 0<V≤V1 and M>ε;

[0036] b. V1<V≤V2 and M>δ;

[0037] c. V>V2 and M>γ;

[0038] Wherein, V is the vehicle speed; M is the initial rainfall or process rainfall; V1 and V2 are the first set value and the second set value of the vehicle speed respectively, and V1<V2; γ, δ, and ε are the third threshold, fourth threshold, and fifth threshold of rainfall respectively; γ<δ<ε.

[0039] The beneficial effects of the present invention are:

[0040] The wiper motor of the present invention provides a wiper position signal to the wiper detection module. The wiper detection module combines the wiper position signal and only selects the first time period after the wiper leaves the stop position when moving upward and the second time period before the wiper enters the stop position when moving downward to calculate the amount of rain on the front windshield. This can avoid the influence of the changes in rain and light caused by the wiper passing through the wiper detection module on the calculation accuracy. At the same time, the time period that needs to be calculated only accounts for about 1 / 3 of the entire wiping cycle, which can greatly reduce the calculation load of the sensor.

[0041] After the first wiping of the present invention, the wiper detection module uses the infrared light collected during the last wiping process as a basis when calculating the next wiping request. The infrared light in the first time period after the wiper leaves the stop position when moving upward and in the second time period before the wiper enters the stop position when moving downward is used to remove the infrared light when the wiper passes through the wiper detection module area. The result is used to calculate the rainfall and determine the next wiping form request, which can avoid the influence of glass cleanliness, wiper blade wear, and residual water film after wiping on the calculation accuracy.

[0042] The wiper detection module of the present invention couples the rainfall amount with the vehicle speed information collected by the vehicle speed detection module. Different vehicle speeds correspond to different rainfall threshold intervals, thus meeting the different requirements of different vehicle speeds for wiper blade forms.

[0043] The present invention improves the accuracy and reliability of automatic windshield wipers by optimizing rainfall calculation logic. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a system principle diagram of the present invention.

[0045] Figure 2 This is a schematic diagram of the detection principle of the rainfall detection module of the present invention.

[0046] Figure 3 This is a schematic diagram showing the rain detection module and the up and down positions of the wipers of the present invention.

[0047] Figure 4 This is a flow chart of the automatic wiper control of the present invention.

[0048] Figure 5It is a rainfall calculation model diagram of the present invention. DETAILED DESCRIPTION

[0049] The following is a further description of specific embodiments of the present invention in conjunction with the accompanying drawings. It should be noted that the description of these embodiments is intended to facilitate understanding of the present invention and does not constitute a limitation of the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0050] like Figure 1-3 As shown, the present invention provides an automobile automatic wiper control system, comprising

[0051] The automatic wiper switch is integrated into the manual wiper lever for easy operation by the driver. When the driver turns it on, it sends an on signal to the rain detection module.

[0052] Vehicle speed detection module, used to detect vehicle speed in real time and send it to rainfall detection module;

[0053] The rain detection module is installed in the upper middle position of the inner surface of the front windshield and includes a light rain sensor and a processing module. When the automatic wiper switch is turned on, the light rain sensor will collect and record the infrared light reception value in real time. The processing module determines the rainfall based on the infrared light reception value and the wiper position signal, and judges the degree of wiper wiping action based on the rainfall and vehicle speed and sends a wiping request to the control module.

[0054] The optical rain sensor consists of an infrared light transmitter and an infrared light receiver. The infrared light emitted by the infrared light transmitter enters the windshield at a certain angle after passing through a lens. It is then reflected by the windshield surface and received by the infrared light receiver after passing through the lens. When there is no rain outside, the incident light is totally reflected by the windshield surface, and the infrared light received by the infrared light receiver has a constant intensity. However, when there is rain outside, the total reflection condition is broken by water droplets on the windshield surface, and the incident light is refracted by the water droplets on the windshield surface. Part of the light is refracted and lost, resulting in a decrease in the intensity of the reflected light received by the infrared light receiver. The larger the raindrop, the larger the area of ​​the windshield surface where the light is refracted, and the greater the loss of infrared light intensity caused by refraction, resulting in a decrease in the intensity of the reflected light received by the infrared light receiver. Therefore, raindrop size is inversely proportional to the infrared light received value and directly proportional to the infrared light loss value. The relationship between the infrared light received value or the infrared light loss value and raindrop size can be used to calculate the amount of rain on the windshield in real time. Each time the processing module receives the infrared light reception value, it also calculates the infrared light loss value each time. The loss value is the difference between the incident light intensity and the reflected light intensity (infrared light reception value). The process rainfall is calculated by combining the minimum value of the infrared light reception value and the infrared light loss value during this scraping process.

[0055] A control module (BSI) is configured to send a wipe signal to the wiper motor after receiving a wipe request;

[0056] The wiper motor is used to control the wiper blade to perform the wiping action after receiving the wiping signal, and is used to feed back the wiper position signal to the rain detection module.

[0057] All of the above modules transmit data / signals via the LIN bus or CAN bus on the vehicle.

[0058] Based on the above automatic wiper control system, the present invention also provides a method for controlling an automatic wiper of an automobile, such as Figure 4 、 Figure 5 As shown, the following steps are included:

[0059] Step 1: After the automatic wiper switch is turned on, obtain the vehicle speed and infrared light reception value in real time;

[0060] Step 2: determining an initial rainfall amount based on an initial infrared light reception value (i.e., a first infrared light reception value), determining a wiper wiping action degree based on the initial rainfall amount and the vehicle speed, and controlling the wiper to perform the first wipe according to the wiper wiping action degree;

[0061] Step 3: While the windshield wipers are wiping, the wiper motor is used to feed back wiper position information. Infrared light reception values ​​are collected during a set period based on the wiper position. An average infrared light value is calculated based on the infrared light reception values ​​during the set period. The process rainfall is determined by the sum of the average infrared light value and the minimum infrared light loss value during the current wiping process. The degree of wiper action is determined based on the process rainfall and vehicle speed, and the wipers are controlled to perform the next wipe according to the degree of wiper action.

[0062] Step 4: Repeat step 3 until the wiper switch is turned off.

[0063] In the above scheme, the process of the wiper performing one wiping operation includes upward wiping and downward wiping. The upward wiping operation is to wipe upward from the downward stop position to the upward stop position, and the downward wiping operation is to wipe downward from the upper stop position to the lower stop position. The set time period is related to the downward stop position, so real-time feedback of the wiper position is required during the wiping process to facilitate the collection of the infrared light reception value in the set time period.

[0064] The set time period includes a first time period from the initial moment when the wiper is at the downward stop position to the moment T1 during upward wiping, and a second time period from the moment T2 to the end moment when the wiper is at the downward stop position during downward wiping. Let the wiping process cycle be T, and the set time period is the starting segment near the starting point (first time period) and the ending segment near the end point (second time period) in the cycle, that is, Figure 5 The value in the middle is the time period. The light rain sensor periodically sends and receives infrared light, so it will receive several infrared light reception values ​​during the set time period.

[0065] In the above scheme, different wiping action levels of the wiper are set in combination with the vehicle speed and the amount of rain, as shown in Table 1. The specific wiping action level of the wiper is any one of no action, intermittent wiping, low-speed wiping, and high-speed wiping. The blade action frequencies of the intermittent wiping, low-speed wiping, and high-speed wiping increase in sequence. For example, intermittent wiping is to shave once at a speed of 40 wipings / minute and then stop for 3.5 seconds. Low-speed wiping is when the motor keeps rotating and shaves at a constant speed of 40 wipings / minute. High-speed wiping is when the motor keeps rotating and shaves at a constant speed of 60 wipings / minute.

[0066] Table 1. Correspondence between vehicle speed, rain threshold, and wiper action level

[0067]

[0068] The detailed description of Table 1 is as follows:

[0069] 1) When any of the following conditions are met, the wiper action is determined to be inactive:

[0070] a. 0<V≤V1 and M≤γ;

[0071] b. V1<V≤V2 and M≤β;

[0072] c. V>V2 and M≤α;

[0073] 2) When any of the following conditions are met, the wiper wiping action is determined to be intermittent wiping:

[0074] a, 0<V≤V1 and γ<M≤δ;

[0075] b. V1<V≤V2 and β<M≤γ;

[0076] c. V>V2 and α<M≤β;

[0077] 3) When any of the following conditions are met, the wiper wiping action is determined to be low speed wiping:

[0078] a, 0<V≤V1 and δ<M≤ε;

[0079] b. V1<V≤V2 and γ<M≤δ;

[0080] c. V>V2 and β<M≤γ;

[0081] 4) When any of the following conditions are met, the wiper action is determined to be high-speed wiping:

[0082] a. 0<V≤V1 and M>ε;

[0083] b. V1<V≤V2 and M>δ;

[0084] c. V>V2 and M>γ;

[0085] Wherein, V is the vehicle speed; M is the initial rainfall or process rainfall; V1 and V2 are the first set value and the second set value of the vehicle speed, respectively, and V1<V2; α, β, γ, δ, and ε are the first threshold, second threshold, third threshold, fourth threshold, and fifth threshold of rainfall, respectively, and α<β<γ<δ<ε.

[0086] The above are only specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be covered by the scope of protection of the present invention. Matters not described in detail in this specification belong to the prior art known to those skilled in the art.

Claims

1. An automatic windshield wiper control system for an automobile, characterized in that: include Automatic wiper switch, used to send an on signal to the rain detection module after the driver turns it on; Vehicle speed detection module, used to detect vehicle speed in real time and send it to rainfall detection module; The rain detection module is used to obtain the infrared light reception value in real time after receiving the start signal, determine the rainfall based on the infrared light reception value and the wiper position signal, determine the degree of wiper wiping action based on the rainfall and vehicle speed, and send a wipe request to the control module; A control module, configured to send a wipe signal to the wiper motor after receiving a wipe request; The wiper motor is used to control the wiper blade to perform the wiper action after receiving the wiper signal, and to feed back the wiper position signal to the rain detection module; The rainfall determined by the rain detection module includes the initial rainfall and the process rainfall. The rain detection module determines the initial rainfall based on the initial infrared light reception value; the rain detection module collects the infrared light reception value in the set time period according to the wiper position, calculates the infrared light average value based on the infrared light reception value, and determines the process rainfall by the sum of the infrared light average value and the minimum value of the infrared light loss value during this wiping process.

2. The automobile automatic wiper control system according to claim 1, characterized in that: The process of the wiper performing one wiping operation includes upward wiping and downward wiping. The upward wiping operation is to wipe upward from the downward stop position to the upward stop position, and the downward wiping operation is to wipe downward from the upper stop position to the lower stop position. The set time period includes a first time period from the initial moment when the wiper is located at the lower stop position to moment T1 during upward wiping and a second time period from moment T2 to the end moment when the wiper is located at the lower stop position during downward wiping.

3. A method for controlling an automatic windshield wiper of an automobile, characterized in that: The following steps are involved: Step 1: After the automatic wiper switch is turned on, obtain the vehicle speed and infrared light reception value in real time; Step 2: determining an initial rainfall amount based on the initial infrared light reception value, determining the degree of wiper wiping action based on the initial rainfall amount and the vehicle speed, and controlling the wiper to perform a first wipe based on the degree of wiper wiping action; Step 3: While the wipers are wiping, the wiper position is detected, infrared light reception values ​​are collected during a set period based on the wiper position, an average infrared light value is calculated based on the infrared light reception values, and the process rainfall is determined by the sum of the average infrared light value and the minimum infrared light loss value during the current wiping process. The degree of wiper wiping action is determined based on the process rainfall and vehicle speed, and the wipers are controlled to perform the next wipe according to the degree of wiping action; Step 4: Repeat step 3 until the wiper switch is turned off.

4. The method for controlling an automatic windshield wiper of an automobile according to claim 3, wherein: The process of the wiper performing one wiping operation includes upward wiping and downward wiping, the upward wiping is wiping from the downward stop position to the upward stop position, and the downward wiping is wiping from the upper stop position to the lower stop position. The set time period includes a first time period from the initial moment when the wiper is located at the lower stop position to moment T1 during upward wiping and a second time period from moment T2 to the end moment when the wiper is located at the lower stop position during downward wiping.

5. The method for controlling the automatic windshield wiper of an automobile according to claim 3, wherein: The wiper's wiping action degree is any one of no action, intermittent wiping, low-speed wiping, and high-speed wiping, and the wiper blade travel speeds of the intermittent wiping, low-speed wiping, and high-speed wiping increase in sequence.

6. The method for controlling the automatic windshield wiper of an automobile according to claim 5, characterized in that: When any of the following conditions are met, the wiper wiping action is determined to be inactive: a. 0<V≤V1 and M≤γ; b. V1<V≤V2 and M≤β; c. V>V2 and M≤α; Wherein, V is the vehicle speed; M is the initial rainfall or process rainfall; V1 and V2 are the first set value and the second set value of the vehicle speed, respectively, and V1<V2; α, β, and γ are the first threshold, second threshold, and third threshold of rainfall, respectively, and α<β<γ.

7. The method for controlling an automatic windshield wiper of a vehicle according to claim 5, wherein: When any of the following conditions are met, the wiper action is determined to be intermittent: a, 0<V≤V1 and γ<M≤δ; b. V1<V≤V2 and β<M≤γ; c. V>V2 and α<M≤β; Wherein, V is the vehicle speed; M is the initial rainfall or process rainfall; V1 and V2 are the first set value and the second set value of the vehicle speed, respectively, and V1<V2; α, β, γ, and δ are the first threshold, second threshold, third threshold, and fourth threshold of rainfall, respectively; α<β<γ<δ.

8. The method for controlling an automatic windshield wiper of a vehicle according to claim 5, wherein: When any of the following conditions are met, the wiper wiping action is determined to be low speed wiping: a, 0<V≤V1 and δ<M≤ε; b. V1<V≤V2 and γ<M≤δ; c. V>V2 and β<M≤γ; Wherein, V is the vehicle speed; M is the initial rainfall or process rainfall; V1 and V2 are the first set value and the second set value of the vehicle speed, respectively, and V1<V2; β, γ, δ, and ε are the second threshold, third threshold, fourth threshold, and fifth threshold of rainfall, respectively; β<γ<δ<ε.

9. The method for controlling an automatic windshield wiper of a vehicle according to claim 5, wherein: When any of the following conditions are met, the wiper action is determined to be high-speed wiping: a. 0<V≤V1 and M>ε; b. V1<V≤V2 and M>δ; c. V>V2 and M>γ; Wherein, V is the vehicle speed; M is the initial rainfall or process rainfall; V1 and V2 are the first set value and the second set value of the vehicle speed respectively, and V1<V2; γ, δ, and ε are the third threshold, fourth threshold, and fifth threshold of rainfall respectively; γ<δ<ε.

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