Control method, device, controller and storage medium for preventing automobile fogging

Abstract

The present invention discloses a control method, device, controller and storage medium for preventing fogging of automobiles, wherein the control method comprises: obtaining the in-car temperature, the inside temperature of the windshield and the relative humidity in the car and determining the in-car dew point temperature; when the inside temperature of the windshield is lower than the in-car dew point temperature, determining the first defog wind speed of the vehicle-mounted air conditioner of the vehicle according to the in-car dew point temperature and the inside temperature of the windshield, and controlling the vehicle-mounted air conditioner to perform defog according to the first defog wind speed; obtaining the light intensity variation at the windshield and determining the second defog wind speed of the vehicle-mounted air conditioner according to the light intensity variation; controlling the vehicle-mounted air conditioner to perform defog according to the first defog wind speed and the second defog wind speed. The above method intervenes in the early stage when the inside of the windshield is prone to fogging and improves the defog efficiency, avoiding the influence on driving after obvious fogging and the safety hazards caused by long-term defog.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a control method, device, controller and storage medium for preventing fogging of an automobile. Background Art

[0002] The fogging of the car windshield will have an extremely adverse effect on the safe driving of the vehicle. Generally speaking, the rainy season, late autumn and winter are the weather conditions when the car windshield is prone to fogging. Especially in winter, when the car heater is turned on, the temperature difference between the inside and outside of the car is large, the humidity inside the car is high, and the water vapor breathed by the people in the car further increases the humidity inside the car, making it more likely to fog.

[0003] When the windshield is fogged, the driver needs to turn on the defog function from time to time to avoid the windshield fogging and affecting the vision, which will bring hidden dangers to driving safety. If the air conditioner is turned on to defog after the windshield is fogged, if the fog is to be eliminated as soon as possible, the air conditioner needs to be turned on with a large air volume to defog, which will cause a lot of air conditioning noise and affect driving; if the large air volume is not turned on, the defog time is long, which will still affect the driving vision and bring hidden dangers. Summary of the invention

[0004] The present invention provides a control method, device, controller and storage medium for preventing fogging of an automobile, so as to solve or partially solve the technical problems that the air conditioner is usually turned on for defogger after the windshield is found to be fogged, the wind noise caused by large air volume defogger affects driving, or the defogger time is long due to small air volume defogger, which creates safety hazards.

[0005] In order to solve the above technical problems, in a first aspect, a control method for preventing fogging of an automobile is provided according to an embodiment of the present invention, comprising:

[0006] Obtain the vehicle interior temperature, windshield inner temperature and vehicle interior relative humidity;

[0007] Determining the dew point temperature in the vehicle according to the temperature in the vehicle and the relative humidity in the vehicle;

[0008] When the temperature inside the windshield is lower than the dew point temperature inside the vehicle, determining a first defog wind speed of the vehicle air conditioner according to the dew point temperature inside the vehicle and the temperature inside the windshield, and controlling the vehicle air conditioner to perform defog according to the first defog wind speed;

[0009] Obtaining a change in light intensity at a windshield, and determining a second defog wind speed of the vehicle air conditioner according to the change in light intensity;

[0010] The vehicle air conditioner is controlled to perform defog according to the first defog wind speed and the second defog wind speed.

[0011] Optionally, determining the first defog wind speed of the vehicle air conditioner according to the vehicle interior dew point temperature and the windshield interior temperature includes:

[0012] The first defog wind speed of the vehicle air conditioner is determined according to the temperature difference and a first corresponding relationship; the temperature difference is the difference between the dew point temperature inside the vehicle and the temperature inside the windshield, and the first corresponding relationship is the corresponding relationship between the temperature difference and the first defog wind speed.

[0013] Optionally, when the temperature difference exceeds a set value, the method further includes:

[0014] The vehicle air conditioner is controlled to cool down.

[0015] Optionally, obtaining the light intensity change at the windshield and determining the second defog wind speed of the vehicle air conditioner according to the light intensity change includes:

[0016] According to a first set time interval, obtaining the light intensity at the windshield corresponding to each collection moment;

[0017] Obtaining the light intensity change according to the light intensity at the current collection moment and the light intensity at the previous collection moment;

[0018] The second demisting wind speed is determined according to the light intensity change amount and a second corresponding relationship; the second corresponding relationship is a corresponding relationship between the light intensity change amount and the second demisting wind speed.

[0019] Optionally, the control method further includes:

[0020] Get the current measured air pressure;

[0021] The step of determining the dew point temperature in the vehicle according to the temperature in the vehicle and the relative humidity in the vehicle comprises:

[0022] The theoretical dew point temperature is determined according to the in-vehicle temperature and the in-vehicle relative humidity; the theoretical dew point temperature is corrected according to the measured air pressure and the standard atmospheric pressure to obtain a corrected dew point temperature, and the corrected dew point temperature is determined as the in-vehicle dew point temperature.

[0023] Optionally, the control method further includes:

[0024] Obtain the outside temperature, outside relative humidity and outside temperature of the windshield;

[0025] Determining the dew point temperature outside the vehicle according to the vehicle outside temperature and the vehicle outside relative humidity;

[0026] When the temperature outside the windshield is lower than the dew point temperature outside the vehicle, the wiper is controlled to operate for defog.

[0027] Further, controlling the wiper to perform defog includes:

[0028] The wiper is controlled to work intermittently according to a second set time interval.

[0029] In a second aspect, a control device for preventing fogging of an automobile is provided according to an embodiment of the present invention, comprising:

[0030] The acquisition module is used to obtain the vehicle interior temperature, the windshield inner temperature, the vehicle interior relative humidity, and the light intensity change at the windshield;

[0031] A first determination module, configured to determine a dew point temperature in the vehicle according to the temperature in the vehicle and the relative humidity in the vehicle;

[0032] A second determination module is used to determine a first defog wind speed of the vehicle air conditioner of the vehicle according to the vehicle dew point temperature and the windshield inner temperature when the temperature inside the windshield is lower than the vehicle interior dew point temperature; and determine a second defog wind speed of the vehicle air conditioner according to the light intensity change;

[0033] A control module is used to control the vehicle air conditioner to perform defog according to the first defog wind speed; or to control the vehicle air conditioner to perform defog according to the first defog wind speed and the second defog wind speed.

[0034] In a third aspect, a controller is provided according to an embodiment of the present invention, the controller comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any one of the control methods described in the first aspect when executing the computer program.

[0035] In a fourth aspect, according to an embodiment of the present invention, there is provided a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of any one of the control methods described in the first aspect are implemented.

[0036] Through one or more technical solutions of the present invention, the present invention has the following beneficial effects or advantages:

[0037] The present invention discloses a control method for preventing automobile fogging. The method determines the dew point temperature in the vehicle according to the temperature in the vehicle and the relative humidity in the vehicle. Then, when the temperature inside the windshield is lower than the dew point temperature in the vehicle and the fogging condition inside the windshield is met, a first defogger wind speed is determined according to the dew point temperature in the vehicle and the temperature inside the windshield. Thus, intervention is made in the early stage when the inside of the windshield is prone to fogging or in time at the initial stage of fogging. The vehicle-mounted air conditioner is automatically controlled to perform ventilation and drying to achieve defogger, thereby avoiding the driving being affected by obvious fogging of the windshield or obvious air conditioner noise caused by turning on the defogger with a large air volume. The second defogger wind speed is determined according to the variation of the light intensity at the windshield because the variation of the light intensity can reflect the defogger effect on the surface of the windshield. According to the second defogger wind speed determined based on the above, combined with the first defogger wind speed, the vehicle-mounted air conditioner is controlled to perform defogger, thereby improving the defogger efficiency and avoiding the hidden danger of driving safety caused by long-term defogger.

[0038] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0040] Figure 1 A flow chart of a method for preventing fogging of a vehicle according to an embodiment of the present invention is shown;

[0041] Figure 2 A schematic diagram of a device involved in a fogging prevention system for a certain vehicle type according to an embodiment of the present invention is shown;

[0042] Figure 3 A temperature-relative humidity-dew point temperature correspondence table according to an embodiment of the present invention is shown;

[0043] Figure 4 A schematic diagram showing a first corresponding relationship between a temperature difference and a first demisting wind speed according to an embodiment of the present invention is shown;

[0044] Figure 5 A schematic diagram showing a second corresponding relationship between the light intensity change and the second demisting wind speed according to an embodiment of the present invention is shown;

[0045] Figure 6A schematic diagram of a control device for preventing fogging of an automobile according to another embodiment of the present invention is shown;

[0046] Figure 7 A schematic diagram of a controller according to another embodiment of the present invention is shown;

[0047] Figure 8 A schematic diagram of a storage medium according to yet another embodiment of the present invention is shown. DETAILED DESCRIPTION

[0048] In order to make the technical personnel in the technical field to which the present application belongs more clearly understand the present application, the technical solution of the present application is described in detail by specific embodiments in conjunction with the accompanying drawings. Throughout the specification, unless otherwise specified, the terms used herein should be understood as the meanings commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meanings as the general understanding of the technical personnel in the field to which the present invention belongs. If there is a contradiction, this specification takes precedence. Unless otherwise specified, the various equipment used in the present invention, etc., can be purchased from the market or can be prepared by existing methods.

[0049] In order to solve the technical problem that the windshield is fogged up first and then the air conditioner is turned on for defog, the wind noise caused by large air volume defog affects driving, or the defog time is long due to small air volume defog, which causes safety hazards, in the first aspect, a control method for preventing fogging of an automobile is provided in an optional embodiment, and the overall idea is as follows:

[0050] The vehicle interior temperature, the windshield inner temperature and the vehicle interior relative humidity are obtained; the vehicle interior dew point temperature is determined according to the vehicle interior temperature and the vehicle interior relative humidity; when the windshield inner temperature is lower than the vehicle interior dew point temperature, the first defog wind speed of the vehicle air conditioner is determined according to the vehicle interior dew point temperature and the windshield inner temperature, and the vehicle air conditioner is controlled to perform defog according to the first defog wind speed; the light intensity change at the windshield is obtained, and the second defog wind speed of the vehicle air conditioner is determined according to the light intensity change; the vehicle air conditioner is controlled to perform defog according to the first defog wind speed and the second defog wind speed.

[0051] The principle of the above control method is: for the problem of fogging on the inside of the windshield, the dew point temperature in the car is determined according to the temperature in the car and the relative humidity in the car, and then when the temperature in the inside of the windshield is lower than the dew point temperature in the car and the fogging condition on the inside of the windshield is met, the first defogger wind speed is determined according to the dew point temperature in the car and the temperature in the windshield, so as to intervene in the early stage when the inside of the windshield is prone to fogging or intervene in time at the early stage of fogging, and automatically control the vehicle air conditioner to perform ventilation and drying to achieve defogger, so as to avoid the windshield being obviously fogged and affecting driving, or the obvious air-conditioning noise caused by turning on the large air volume defogger; and the second defogger wind speed is determined according to the change in light intensity at the windshield, because the change in light intensity can reflect the defogger effect on the surface of the windshield, and the vehicle air conditioner is controlled to perform defogger according to the second defogger wind speed determined based on this, combined with the first defogger wind speed, so as to improve the defogger efficiency and avoid the driving safety hazards caused by long-term defogger.

[0052] Next, the above scheme is further described in conjunction with specific implementation methods:

[0053] In an optional embodiment, the above solution is applied to a controller of a certain vehicle model. The controller may be a vehicle controller, an air conditioning controller or a newly added controller, and the control method for preventing fogging is as follows: Figure 1 As shown, including S1 to S5, the details are as follows:

[0054] S1: Obtain the interior temperature of the vehicle, the temperature inside the windshield, and the relative humidity inside the vehicle;

[0055] Specifically, the in-vehicle temperature refers to the temperature in the passenger compartment of the vehicle, which is collected by a temperature sensor installed in the passenger compartment.

[0056] If the windshield is double-layered, the inside temperature of the windshield refers to the temperature of the inner layer of the windshield; if the windshield is single-layered, the inside temperature of the windshield refers to the inner surface temperature of the windshield on the passenger compartment side; the inside temperature of the windshield is collected by a temperature sensor arranged on the inner surface of the windshield.

[0057] The relative humidity inside the vehicle refers to the relative humidity inside the vehicle's passenger compartment, which is collected by a humidity sensor installed in the passenger compartment.

[0058] The above-mentioned various sensors establish a communication connection with the controller to transmit the electrical signals obtained from the test to the controller for processing. At the same time, the controller establishes a communication connection with the vehicle air conditioner to send a control signal to the vehicle air conditioner.

[0059] S2: determining the dew point temperature inside the vehicle according to the temperature inside the vehicle and the relative humidity inside the vehicle;

[0060] Specifically, the dew point temperature in the vehicle can be determined through a preset mapping or conversion relationship between temperature, relative humidity and dew point temperature. The general rule is that the dew point temperature is positively correlated with the temperature and relative humidity in the vehicle, that is, as the temperature in the vehicle increases, the dew point temperature increases; as the relative humidity increases, the dew point temperature increases.

[0061] In some optional embodiments, the dew point temperature may be corrected according to the current air pressure to improve the control accuracy of the air conditioner defogger, as follows:

[0062] Obtain the current measured air pressure; determine the theoretical dew point temperature according to the in-vehicle temperature and the in-vehicle relative humidity; correct the theoretical dew point temperature according to the measured air pressure and the standard atmospheric pressure to obtain a corrected dew point temperature, and determine the corrected dew point temperature as the in-vehicle dew point temperature.

[0063] Let the theoretical dew point temperature be T d , P w To measure air pressure, P0 is the standard atmospheric pressure, then the corrected dew point temperature T under different air pressures is d ' can be determined according to the following formula:

[0064] T d =Td×[1+t×(P w -P0) / P0] (1)

[0065] Wherein, t is the temperature compensation coefficient, and in this embodiment, t can be a constant: 2.5.

[0066] S3: when the temperature inside the windshield is lower than the dew point temperature inside the vehicle, determining a first defog wind speed of the vehicle air conditioner according to the dew point temperature inside the vehicle and the temperature inside the windshield, and controlling the vehicle air conditioner to perform defog according to the first defog wind speed;

[0067] When the temperature on the inside of the windshield is lower than the dew point temperature inside the car, it means that the inside of the windshield meets the fogging conditions. At this time, the car air conditioner needs to be controlled to enter the defog mode. The defog wind speed required for the defog mode is determined based on the dew point temperature inside the car and the temperature on the inside of the windshield.

[0068] An optional determination method is:

[0069] The first defog wind speed of the vehicle air conditioner is determined according to the temperature difference and the first corresponding relationship; the temperature difference is the difference between the dew point temperature in the vehicle and the temperature inside the windshield; the first corresponding relationship is the corresponding relationship between the temperature difference and the first defog wind speed.

[0070] The first corresponding relationship may be a linear relationship, a polynomial relationship or a logarithmic relationship, which may be specifically determined through a calibration experiment.

[0071] The defog wind speed can be a specific wind speed value at the air outlet of the vehicle air conditioner, or it can be the ratio between the specific wind speed value at the air outlet and the maximum wind speed value at the air outlet, and can be selected according to actual needs.

[0072] In steps S1 to S3, when it is detected that the inside of the windshield meets the fogging conditions, the vehicle air conditioner is automatically controlled to perform defogger in advance and the corresponding defogger wind speed is determined. The passenger compartment is ventilated and dried by the first defogger wind speed, which can reduce the relative humidity of the air at the windshield in the vehicle, thereby reducing the dew point temperature, making the temperature inside the windshield higher than the dew point temperature, and avoiding fogging on the inside of the windshield.

[0073] In some optional embodiments, if the temperature difference is large and greater than the set value, it means that the temperature inside the windshield is significantly lower than the dew point temperature inside the vehicle, and the vehicle air conditioner can be controlled to cool down. When the temperature inside the vehicle is reduced, the dew point temperature inside the vehicle is reduced synchronously to reduce the temperature difference between the dew point temperature inside the vehicle and the temperature inside the windshield, thereby speeding up the defog speed.

[0074] The set value may range from 5 to 10°C, preferably 6°C, 6.5°C and 7°C.

[0075] During the defog process, the controller will continue to detect the relationship between the dew point temperature inside the car and the temperature on the inside of the windshield. When the temperature on the inside of the windshield is higher than the dew point temperature inside the car, it indicates that the conditions for fogging on the inside of the windshield are no longer met. The controller can send a signal to turn off the defog mode of the car air conditioner.

[0076] In order to improve the defog effect and reduce the defog time without generating excessive wind noise, the next step is to monitor the changes in light intensity:

[0077] S4: Obtaining a change in light intensity at the windshield, and determining a second defog wind speed of the vehicle air conditioner according to the change in light intensity;

[0078] Specifically, the light intensity variation can be collected by a light sensor disposed at the windshield. Similarly, the light sensor is in communication connection with the controller to send a measured light intensity signal to the controller.

[0079] The change in light intensity may be the difference between the front and rear light intensities or the ratio of the front and rear light intensities, and may be selected according to actual needs.

[0080] An optional method for determining the second demisting wind speed is:

[0081] According to a first set time interval, the light intensity at the windshield corresponding to each collection moment is obtained; according to the light intensity at the current collection moment and the light intensity at the previous collection moment, the light intensity change is obtained; according to the light intensity change and a second corresponding relationship, the second defogger wind speed is determined; the second corresponding relationship is the corresponding relationship between the light intensity change and the second defogger wind speed.

[0082] The first set time interval can be determined according to demand, such as 1 to 3 seconds;

[0083] If not otherwise specified, in this embodiment, the ratio of the light intensity at the current collection moment to the light intensity at the previous collection moment is used as the light intensity change amount.

[0084] The second corresponding relationship is a predetermined mapping relationship between the light intensity change and the second defogger wind speed, which can be determined according to a calibration test. The corresponding relationship can be a linear relationship, a polynomial relationship, an exponential relationship or a logarithmic relationship.

[0085] The general rule of the second corresponding relationship is: if the change in light intensity is positive and increasing, it means that the rate of increase of the light intensity at the current collection moment relative to the light intensity at the previous collection moment has increased, and the defogging effect is good, then the second defogging wind speed can be appropriately reduced; if the change in light intensity decreases or is even negative, it means that the rate of increase of the light intensity at the current collection moment relative to the light intensity at the previous collection moment has decreased or even been negative, indicating that the defogging effect is poor, and the second defogging wind speed needs to be appropriately increased.

[0086] S5: Controlling the vehicle air conditioner to perform defog according to the first defog wind speed and the second defog wind speed.

[0087] Specifically, the target defog wind speed of the vehicle air conditioner can be determined according to the sum of the first defog wind speed and the second defog wind speed, and the vehicle air conditioner can be controlled to perform defog based on the target defog wind speed, as follows:

[0088] Sw=Sw1+Sw2 (2)

[0089] Among them, Sw is the target demisting wind speed, Sw1 is the first demisting wind speed, and Sw2 is the second demisting wind speed.

[0090] Alternatively, the second demisting wind speed may be multiplied by a correction coefficient l and then added to the first demisting wind speed to obtain the target demisting wind speed, as follows:

[0091] Sw=Sw1+1×Sw2 (3)

[0092] The above content introduces the control logic of turning on the vehicle air conditioner to defog when the inner side of the windshield meets the fogging condition. In order to deal with the problem of fogging on the outer side of the windshield, in some optional embodiments, the control method also includes:

[0093] Obtaining the vehicle's outside temperature, the vehicle's outside relative humidity and the windshield's outside temperature; determining the vehicle's outside dew point temperature according to the vehicle's outside temperature and the vehicle's outside relative humidity; and controlling the wipers to perform defogger operations when the windshield's outside temperature is lower than the vehicle's outside dew point temperature.

[0094] Specifically, a temperature sensor and a humidity sensor may be arranged outside the car to detect the temperature outside the car and the relative humidity outside the car respectively. If the windshield is double-layered or more-layered glass, the temperature sensor arranged at the outer layer of the windshield is used to detect the temperature outside the windshield; if the windshield is single-layered glass, the temperature sensor arranged at the outer side of the windshield is used to detect the temperature outside the windshield.

[0095] The principle of determining the dew point temperature outside the vehicle based on the outside temperature and the outside relative humidity is the same as the principle of determining the dew point temperature inside the vehicle; similarly, when the temperature outside the windshield is lower than the outside dew point temperature, the conditions for fogging on the outside of the windshield are met, and at this time, the wipers are controlled to defog the outside of the windshield.

[0096] The above scheme automatically turns on the wipers in the early stage of fogging or in the early stage of fogging when it detects that the outer side of the windshield meets the fogging conditions, and eliminates the water mist on the outside of the windshield in advance through the wipers to avoid affecting the field of vision and causing safety hazards.

[0097] Optionally, the wiper defogger can be controlled in an intermittent manner: that is, the wiper is controlled to work intermittently according to a second set time interval. Intermittent operation means that the wiper is started once at a certain interval to wipe the water mist on the outside of the windshield. The reason for intermittently turning on the wiper is to minimize the interference of the defogger process to the driver. Optionally, the second set time interval can be in the range of 4 to 8 seconds, and the preferred time is 5 seconds, 6 seconds, etc.

[0098] If it is detected that the temperature outside the windshield is higher than the dew point temperature outside the vehicle, it means that the conditions for fogging on the outside of the windshield are no longer met, and the wipers are prohibited from continuing to work.

[0099] In the following optional embodiment, the above solution is described in combination with a specific application scenario:

[0100] The control method provided by the present invention is applied in a certain vehicle model, and the hardware structure involved is as follows Figure 2 As shown, including:

[0101] Controller 100: is disposed in the passenger compartment of the vehicle, and is used to receive various sensor signals and issue control instructions according to the control method of this embodiment to control the air volume and temperature of the air conditioner or control the operation of the wiper;

[0102] In-car temperature sensor 201: Set at the lower part of the windshield, used to detect the temperature inside the car, denoted as T i ;

[0103] The vehicle interior temperature sensor 202 is set on the inner surface of the windshield and is used to detect the temperature of the inner surface of the vehicle windshield, that is, the temperature inside the windshield, which is recorded as T gi ;

[0104] The vehicle exterior temperature sensor 203 is set outside the windshield and is used to detect the vehicle exterior temperature, which is denoted as T o ;

[0105] The vehicle external temperature sensor 204 is set on the outer surface of the windshield and is used to detect the temperature of the outer surface of the vehicle windshield, that is, the outer temperature of the windshield, which is denoted as T go ;

[0106] In-vehicle humidity sensor 301: It is set at the lower part of the windshield and is used to detect the humidity at the windshield inside the vehicle, that is, the relative humidity inside the vehicle, denoted as H i ;

[0107] The outside humidity sensor 302 is set outside the windshield and is used to detect the humidity at the outside windshield of the vehicle, that is, the outside relative humidity, denoted as H o ;

[0108] Air pressure sensor 400: It is installed on the instrument panel and is used to measure the atmospheric pressure of the air, that is, to measure the air pressure, which is recorded as P w ;

[0109] Light sensor 500: installed on the instrument panel below the windshield, used to detect the light intensity at the windshield, denoted as G d ;

[0110] Air conditioning system 600: used to provide cold / warm air and dehumidify the car to adjust the air temperature and humidity in the car;

[0111] Wiper system 700: used for scraping the outer surface of the windshield to remove the water mist on the outer side of the windshield.

[0112] The specific control process of this embodiment is as follows:

[0113] Step 1: Power on the vehicle;

[0114] Step 2: Various temperature sensors and humidity sensors, as well as light sensors and air pressure sensors respectively detect the temperature inside the vehicle, the temperature outside the vehicle, the relative humidity inside the vehicle, the relative humidity outside the vehicle, the light intensity at the windshield, and the air pressure, and send the measurement signals to the controller 100;

[0115] Step 3: The controller 100 receives the vehicle interior temperature signal T i , Windshield inner temperature signal T gi , relative humidity signal H in the car i 、Outside temperature signal T o , Windshield outer temperature signal T go , the relative humidity signal outside the vehicle H o , light intensity signal G d And the measured air pressure signal P in the car w ;

[0116] Step 4: The controller 100 determines the fogging risk and degree according to the preset control logic, and issues a corresponding action instruction; the control logic includes the preset judgment logic C1 for fogging on the inside of the windshield and the preset judgment logic C2 for fogging on the outside of the windshield;

[0117] 1) Preset judgment logic C1 for fogging of the inner side of the windshield:

[0118] If the fogging condition of the inner surface of the windshield is met, the air conditioning ventilation and defogger function is turned on; after the air at the windshield in the car is ventilated and dried by the air conditioning, the relative humidity becomes lower, and the corresponding dew point is increased to avoid condensation of water vapor on the inner side of the windshield in the car. The control method for turning on the air conditioning defogger is: judging the degree of fogging according to the comparison of the detected temperature in the car, the relative humidity in the car, and the light intensity, and turning on the air volume Sw of the air conditioning defogger, (Sw = current outlet wind speed S / outlet maximum wind speed S) as follows: the air volume control method K1 for air conditioning defogger;

[0119] The specific scheme of judgment logic C1 is as follows:

[0120] Scenario 1: Ti>To, the windshield is fogged up inside the car (e.g. when the heating mode is turned on in winter)

[0121] The controller receives the detected vehicle interior temperature T i , relative humidity in the car H i , by looking up the table to get this temperature T i , relative humidity H i Dew point T di , when the inner surface temperature of the windshield is T gi ≤T di When the air conditioner is turned on to defog, the air conditioning system dehumidifies the air in the car, reduces the relative humidity, and prevents the inner surface of the glass from fogging in time.

[0122] For example, the temperature sensor 201 in the car measures the temperature Ti in the car = 18°C, and the humidity sensor 301 in the car measures the relative humidity in the car at 80%. Figure 3 The dew point comparison table shown in the figure shows the dew point T of the air vapor in the car. di The temperature of the inner surface of the windshield is 14.5°C, and the temperature sensor 202 in the vehicle measures the temperature T gi =14℃, due to T gi <T di , so it is judged that the inner surface of the windshield is about to fog up, and the controller turns on the air conditioning to ventilate and dehumidify to reduce the humidity in the car. di -T gi =0.5℃, so the query is Figure 4 The first corresponding relationship shown in FIG. 1 determines that the first defog wind speed Sw1 is 10%, and then controls the ventilation and defog of the vehicle air conditioner according to the first defog wind speed Sw1;

[0123] It should be noted that the defog wind speed in this embodiment is a percentage of the maximum wind speed, that is, Sw=actual wind speed S at the current air outlet / maximum wind speed Smax at the air outlet.

[0124] Furthermore, in determining the dew point temperature T di After that, it can be corrected in combination with the current measured air pressure P0, as follows:

[0125] T di '=T di ×[1+t×(P w -P0) / P0] (4)

[0126] In the above formula:

[0127] Tdi' is the corrected in-vehicle dew point temperature under different measuring air pressures;

[0128] Pw is the measured air pressure value;

[0129] t is the temperature compensation coefficient, which is taken as a constant of 2.5.

[0130] After turning on the air conditioning defogger, the defogger effect is confirmed by comparing the change in light intensity at the windshield, and the second defogger wind speed is determined for correction.

[0131] The controller 100 records the light intensity G at the current moment after the air conditioner defogger is turned on. d2 The light intensity G at the previous moment d1 The comparison of the illumination ratio k = G d2 / G d1as the illumination intensity variation; and then determine the second demisting wind speed Sw2 according to the second corresponding relationship between the illumination ratio k and the wind speed ratio. An example of a second corresponding relationship is as follows: Figure 5 shown.

[0132] For example, the illumination ratio between the current moment and the previous moment is k = 1.05, and the query Figure 5 The corresponding relationship determines that Sw2=5%, so the total defog wind speed of the current vehicle air conditioner Sw=Sw1+Sw2=10%+5%=15%.

[0133] Furthermore, when it is detected that the temperature difference δt exceeds a set value (set to 6.5° C. in this embodiment), the air conditioner is automatically controlled to cool down, thereby eliminating water mist better and faster.

[0134] Scenario 2: T i <T o The windshield is fogged up on the inside of the car (such as when the air conditioner is turned on in the summer)

[0135] Similarly, the controller 100 receives the detected vehicle interior temperature T i , relative humidity in the car H i , by looking up the table to get this temperature T i , relative humidity H i Dew point T di , when the inner surface temperature of the windshield is T gi ≤T di When the air conditioner is turned on for defogger, the air conditioning system dehumidifies the air inside the car, reduces the relative humidity, and can prevent the inner surface of the glass from fogging in time.

[0136] For example: the in-car temperature sensor 201 measures the in-car temperature T i = 22°C, the humidity sensor 301 in the car measures the relative humidity in the car to be 95%. At this time, the dew point of the air vapor in the car is T di is 21.2℃, when the temperature sensor 202 in the vehicle measures the inner surface temperature of the windshield glass T gi is 21°C, due to T gi <T di , so it is judged that the inner surface of the windshield is about to fog up, and the controller turns on the air conditioner for ventilation and dehumidification to reduce the air humidity in the car. Since the temperature difference is 0.2°C, the first defogging wind speed for turning on the air conditioner is 2.5%.

[0137] The other control logic of scenario 2 is the same as that of scenario 1 and will not be elaborated here.

[0138] 2) Preset judgment logic C2 for fogging of the outer side of the windshield:

[0139] If the windshield outer surface fogging condition is met, that is, according to the outside temperature To , relative humidity outside the vehicle H o , query Figure 3 Determine the dew point temperature T outside the vehicle do , and meet the windshield outer temperature T go <T do , the controller 100 automatically turns on the wiper system 700; the water vapor condenses and fogs on the windshield outside the vehicle, and is promptly cleared by the wipers; further, an intermittent wiper mode is adopted, with an interval time of t=5s.

[0140] Step 6: When the controller 100 receives the temperature, humidity, light intensity and air pressure detected by the temperature sensor, humidity sensor, light sensor and air pressure sensor respectively, and determines according to the judgment logic C1 that the defogging condition inside the windshield is not met, the controller 100 determines that there is no risk of fogging of the windshield, and the controller 100 sends a signal to turn off the air conditioner defogger function, otherwise the air conditioner defogger function is turned on and the defogger wind speed is kept at Sw;

[0141] Alternatively, when the controller 100 receives the temperature, humidity, light intensity, and air pressure detected by the temperature sensor, humidity sensor, light sensor, and air pressure sensor, respectively, and determines according to the judgment logic C2 that the defogging condition outside the windshield is not met, the control of intermittently opening the wiper is turned off;

[0142] Step 7: Control ends.

[0143] In general, this embodiment collects the temperature inside and outside the car, the humidity in the windshield area, and the temperature inside and outside the glass and the light intensity for comprehensive judgment during driving, intervenes in the early stage of fogging, and ventilates and dries in advance, thereby reducing the occurrence of fogging during driving, or defogs in advance in the early stage of fogging, avoiding the driving safety hazards of air conditioning wind noise and windshield fogging that affects the field of vision due to the need to turn on high-volume defogger after fogging.

[0144] In a second aspect, in another optional embodiment, a control device for preventing fogging of an automobile is provided, such as Figure 6 As shown, including:

[0145] The acquisition module 10 is used to obtain the vehicle interior temperature, the windshield inner temperature, the vehicle interior relative humidity, and the light intensity change at the windshield;

[0146] A first determination module 20, configured to determine a dew point temperature in the vehicle according to the temperature in the vehicle and the relative humidity in the vehicle;

[0147] The second determination module 30 is used to determine a first defog wind speed of the vehicle air conditioner of the vehicle according to the vehicle dew point temperature and the windshield inner temperature when the temperature inside the windshield is lower than the vehicle interior dew point temperature; and determine a second defog wind speed of the vehicle air conditioner according to the light intensity change;

[0148] The control module 40 is used to control the vehicle air conditioner to perform defog according to the first defog wind speed; or to control the vehicle air conditioner to perform defog according to the first defog wind speed and the second defog wind speed.

[0149] Optionally, the second determining module 30 is used to:

[0150] The first defog wind speed of the vehicle air conditioner is determined according to the temperature difference and the first corresponding relationship; the temperature difference is the difference between the dew point temperature in the vehicle and the temperature inside the windshield, and the first corresponding relationship is the corresponding relationship between the temperature difference and the first defog wind speed.

[0151] Furthermore, when the temperature difference exceeds a set value, the control module 40 is used to:

[0152] Control the vehicle air conditioner to cool down.

[0153] Optionally, the second determining module 30 is used to:

[0154] According to a first set time interval, obtaining the light intensity at the windshield corresponding to each collection moment;

[0155] Obtaining the light intensity change according to the light intensity at the current collection moment and the light intensity at the previous collection moment;

[0156] The second demisting wind speed is determined according to the light intensity change amount and a second corresponding relationship; the second corresponding relationship is a corresponding relationship between the light intensity change amount and the second demisting wind speed.

[0157] Optionally, the acquisition module 10 is used to obtain the current measured air pressure;

[0158] The first determining module 20 is used for:

[0159] The theoretical dew point temperature is determined according to the in-vehicle temperature and the in-vehicle relative humidity; the theoretical dew point temperature is corrected according to the measured air pressure and the standard atmospheric pressure to obtain a corrected dew point temperature, and the corrected dew point temperature is determined as the in-vehicle dew point temperature.

[0160] Optionally, the acquisition module 10 is used to:

[0161] Obtain the outside temperature, outside relative humidity and outside temperature of the windshield;

[0162] The first determining module 20 is used for:

[0163] Determining the dew point temperature outside the vehicle according to the vehicle outside temperature and the vehicle outside relative humidity;

[0164] The control module 40 is used for:

[0165] When the temperature outside the windshield is lower than the dew point temperature outside the vehicle, the wiper is controlled to operate for defog.

[0166] Furthermore, the control module 40 is used for:

[0167] The wiper is controlled to work intermittently according to a second set time interval.

[0168] In a third aspect, based on the same inventive concept as the above-mentioned embodiment, in another optional embodiment, as Figure 7 As shown, a controller 700 is provided, including a processor 720 and a memory 710, wherein the memory 710 is coupled to the processor 720, and the memory 710 stores a computer program 711, and when the computer program 711 is executed by the processor 720, the controller 700 executes the steps of the control method described in the aforementioned embodiment.

[0169] In a fourth aspect, based on the same inventive concept as the above-mentioned embodiment, in another optional embodiment, as Figure 8 As shown, a computer-readable storage medium 800 is provided, on which a computer program 811 is stored. When the program is executed by a processor, the steps of the control method in the aforementioned embodiment are performed.

[0170] Through one or more embodiments of the present invention, the present invention has the following beneficial effects or advantages:

[0171] The present invention discloses a control method for preventing automobile fogging. The method determines the dew point temperature in the vehicle according to the temperature in the vehicle and the relative humidity in the vehicle. Then, when the temperature inside the windshield is lower than the dew point temperature in the vehicle and the fogging condition inside the windshield is met, a first defogger wind speed is determined according to the dew point temperature in the vehicle and the temperature inside the windshield. Thus, intervention is made in the early stage when the inside of the windshield is prone to fogging or in time at the initial stage of fogging. The vehicle-mounted air conditioner is automatically controlled to perform ventilation and drying to achieve defogger, thereby avoiding the driving being affected by obvious fogging of the windshield or obvious air conditioner noise caused by turning on the defogger with a large air volume. The second defogger wind speed is determined according to the variation of the light intensity at the windshield because the variation of the light intensity can reflect the defogger effect on the surface of the windshield. According to the second defogger wind speed determined based on the above, combined with the first defogger wind speed, the vehicle-mounted air conditioner is controlled to perform defogger, thereby improving the defogger efficiency and avoiding the hidden danger of driving safety caused by long-term defogger.

[0172] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0173] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A control method for preventing fogging of an automobile, characterized in that: The control method comprises: Obtain the vehicle interior temperature, windshield inner temperature and vehicle interior relative humidity; Determining the dew point temperature in the vehicle according to the temperature in the vehicle and the relative humidity in the vehicle; When the temperature inside the windshield is lower than the dew point temperature inside the vehicle, determining a first defog wind speed of the vehicle air conditioner according to the dew point temperature inside the vehicle and the temperature inside the windshield, and controlling the vehicle air conditioner to perform defog according to the first defog wind speed; Obtaining a change in light intensity at a windshield, and determining a second defog wind speed of the vehicle air conditioner according to the change in light intensity; Controlling the vehicle air conditioner to perform defog according to the first defog wind speed and the second defog wind speed; The step of determining a first defog wind speed of the vehicle air conditioner according to the vehicle interior dew point temperature and the windshield interior temperature includes: Determining a first defog wind speed of the vehicle air conditioner according to a temperature difference and a first corresponding relationship; the temperature difference is a difference between a dew point temperature in the vehicle and a temperature inside the windshield, and the first corresponding relationship is a corresponding relationship between the temperature difference and the first defog wind speed; When the temperature difference exceeds a set value, the method further includes: Controlling the vehicle air conditioner to cool down; When the temperature inside the vehicle is reduced, the dew point temperature inside the vehicle is reduced synchronously to reduce the temperature difference between the dew point temperature inside the vehicle and the temperature inside the windshield; The control method further includes: obtaining the current measured air pressure; The step of determining the dew point temperature in the vehicle according to the temperature in the vehicle and the relative humidity in the vehicle comprises: The theoretical dew point temperature is determined according to the in-vehicle temperature and the in-vehicle relative humidity; the theoretical dew point temperature is corrected according to the measured air pressure and the standard atmospheric pressure to obtain a corrected dew point temperature, and the corrected dew point temperature is determined as the in-vehicle dew point temperature.

2. The control method according to claim 1, characterized in that: The step of obtaining a change in light intensity at a windshield and determining a second defog wind speed of the vehicle air conditioner according to the change in light intensity includes: According to a first set time interval, obtaining the light intensity at the windshield corresponding to each collection moment; Obtaining the light intensity change according to the light intensity at the current collection moment and the light intensity at the previous collection moment; The second demisting wind speed is determined according to the light intensity change amount and a second corresponding relationship; the second corresponding relationship is a corresponding relationship between the light intensity change amount and the second demisting wind speed.

3. The control method according to any one of claims 1 to 2, characterized in that: Also includes: Obtain the outside temperature, outside relative humidity and outside temperature of the windshield; Determining the dew point temperature outside the vehicle according to the vehicle outside temperature and the vehicle outside relative humidity; When the temperature outside the windshield is lower than the dew point temperature outside the vehicle, the wiper is controlled to operate for defog.

4. The control method according to claim 3, characterized in that: The controlling of the wiper to perform defog operation comprises: The wiper is controlled to work intermittently according to a second set time interval.

5. A control device for preventing fogging of an automobile, the control device being used to implement the steps of the control method as claimed in any one of claims 1 to 4, characterized in that: The control device comprises: The acquisition module is used to obtain the vehicle interior temperature, the windshield inner temperature, the vehicle interior relative humidity, and the light intensity change at the windshield; A first determination module, configured to determine a dew point temperature in the vehicle according to the temperature in the vehicle and the relative humidity in the vehicle; A second determination module is used to determine a first defog wind speed of the vehicle air conditioner of the vehicle according to the vehicle dew point temperature and the windshield inner temperature when the temperature inside the windshield is lower than the vehicle interior dew point temperature; and determine a second defog wind speed of the vehicle air conditioner according to the light intensity change; A control module is used to control the vehicle air conditioner to perform defog according to the first defog wind speed; or to control the vehicle air conditioner to perform defog according to the first defog wind speed and the second defog wind speed.

6. A controller, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the control method according to any one of claims 1 to 4 are implemented.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the control method according to any one of claims 1 to 4 are implemented.

Images