Water level detection device, water level detection method, storage medium and program product

Abstract

The embodiment of the invention provides a water level detection device, a water level detection method, a storage medium and a program product, and the device comprises a machine body mechanism, an isolation type cavity, an area outside the cavity, a machine head mechanism, a first sensor, a control device and the like. The water level detection based on the test signal transmission time and the total height of the device is realized, and a device basis is provided for water level measurement which is accurate, high in anti-interference performance and high in stability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of liquid level detection, in particular to a water level detection device, a water level detection method, a storage medium and a program product. BACKGROUND

[0002] With the improvement of people's living quality, the concern for indoor air quality is increasing, and humidifiers have become common household and office appliances. Under such background, the water level detection technology of humidifiers is also developing. On the one hand, there are various types of humidifier products on the market, from traditional simple humidifiers to high-end humidifiers with intelligent functions, and the application degree and level of water level detection technology are uneven. Some low-end products still rely on simple manual observation of water level, while high-end products increasingly use advanced sensor technology to achieve accurate detection and intelligent control of water level.

[0003] On the other hand, with the rise of the Internet of Things and smart home concepts, the trend of intelligent humidifiers is becoming more and more obvious. As an important part of the intelligent operation of humidifiers, water level detection not only needs to accurately detect the water level, but also needs to effectively interact with other functional modules of the device and user terminals, such as remote monitoring of water level through mobile phone APP, automatic water filling and power protection functions, to improve user experience. At the same time, consumers' requirements for the safety and reliability of humidifiers are also increasing, which prompts manufacturers to continuously improve water level detection technology, improve detection accuracy, and reduce safety hazards such as dry burning and water leakage caused by water level problems. SUMMARY

[0004] The purpose of the embodiments of the present application is to provide a water level detection device, a water level detection method, a storage medium and a program product, to achieve the technical effect of improving the stability and precision of water level detection.

[0005] The first aspect of the embodiments of the present application provides a water level detection device, comprising: a body mechanism, the body mechanism comprising an isolated cavity for water storage and an outer cavity area; the water surface of the isolated cavity is consistent with the water surface of the outer cavity area in height; the isolated cavity comprises a water storage part and a non-water storage part; the head mechanism is installed on the body mechanism; the head mechanism comprises a first sensor and a control device; the first sensor is used to emit and receive test signals to the water surface of the isolated cavity; the control device is used to determine the water level height of the water storage part according to the transmission time of the test signal in the non-water storage part and the total height of the water level detection device.

[0006] In the implementation process, the first sensor of the head mechanism and the control device are used to realize water level detection based on the transmission time of the test signal and the total height of the device, thereby providing a device basis for precise, strong anti-interference and high stability water level measurement.

[0007] Further, the fuselage mechanism further comprises a second sensor installed in the fuselage mechanism for collecting water quality state parameters of the water body.

[0008] In the implementation process, the second sensor in the fuselage mechanism collects water quality state parameters of the water body, thereby providing a basis for detection correction for water quality changes, so that the device can still maintain high-precision detection through correction when the water quality changes (such as adding essential oils, mosquito repellent, etc.), thereby ensuring the stability of the detection results.

[0009] Further, the fuselage mechanism further comprises a third sensor installed below the fuselage mechanism for collecting the total weight of the water level detection device and the internal water body.

[0010] In the implementation process, the third sensor below the fuselage mechanism collects the total weight of the device and the internal water body, and forms a complement with the first sensor, so that the water level can be calculated through the weight data when the first sensor is in the measurement blind area, thereby effectively expanding the measurement range and improving the overall robustness of the device.

[0011] Further, the fuselage mechanism further comprises a fourth sensor installed in the fuselage mechanism for collecting water temperature parameters.

[0012] In the implementation process, the fourth sensor in the fuselage mechanism collects water temperature parameters, thereby providing a compensation basis for the influence of water temperature changes on water density, so that the device can still accurately calculate the water density when the water temperature fluctuates, thereby ensuring the water level calculation accuracy based on the weight, reducing the interference of environmental temperature changes on the detection results, and enhancing the stability of the device in different temperature environments.

[0013] The second aspect of the embodiment of the present application provides a water level detection method based on the water level detection device of the first aspect, the method is applied to the control device of the head mechanism; the method comprises: In the case where the distance between the water surface of the isolated cavity and the first sensor exceeds the preset distance threshold, the first sensor is instructed to emit a test signal to the water surface of the isolated cavity; the isolated cavity is located in the fuselage mechanism, the head mechanism is installed on the fuselage mechanism, the fuselage mechanism further comprises an extracavity area, the water surface of the isolated cavity is consistent with the water surface of the extracavity area, the isolated cavity comprises a water storage part and a non-water storage part, the first sensor is located in the head mechanism, and the preset distance threshold is determined based on the measurement blind distance of the first sensor. acquiring a transmission time of the test signal in the non-accumulation part; acquiring a total height of the water level detection device; determining a water level height of the accumulation part in the isolated cavity based on the transmission time and the total height.

[0014] In the above implementation process, when the distance between the water surface of the isolated cavity and the first sensor exceeds a preset threshold value determined based on a measurement blind area, a test signal is emitted by the first sensor, and the water level is calculated based on the signal transmission time and the total height, so as to fully utilize the advantage of the first sensor in rapid measurement, realize real-time detection, and timely reflect the water level change.

[0015] Further, the method further comprises: In the case where the distance does not exceed the preset distance threshold, acquiring a total weight of the water level detection device and the internal water body collected by the third sensor; acquiring a bottom cross-sectional area of the water level detection device and a water density of the water body in the isolated cavity; determining the water level height of the accumulation part based on the bottom cross-sectional area, the water density, and the weight.

[0016] In the above implementation process, when the distance between the water surface of the isolated cavity and the first sensor does not exceed the preset threshold value, the water level is calculated based on the total weight collected by the third sensor, in combination with the bottom cross-sectional area of the device and the water density, so as to fully utilize the advantage of the weighing method in close-range detection, make up for the deficiency of the TOF technology in the blind area, and realize high-precision detection in the blind area.

[0017] Further, the water density is acquired by the following steps: acquiring a water quality state parameter of the water body in the isolated cavity collected by the second sensor; determining a water quality density correction coefficient corresponding to the water quality state parameter based on the water quality state parameter; the water quality density correction coefficient is positively correlated with the water quality state parameter; determining the water density based on a preset pure water standard density and the water quality density correction coefficient.

[0018] In the above implementation process, the water quality density correction coefficient positively correlated with the water quality state parameter is determined according to the water quality state parameter collected by the second sensor, and the water density is calculated in combination with the pure water standard density, so as to effectively compensate the influence of water quality change on the water density, make the water level calculation based on the weight more accurate, and enhance the detection precision and anti-interference ability of the device under the condition of water quality change.

[0019] Further, the determination of the water density based on the preset pure water standard density and the water quality density correction coefficient comprises: acquiring a water body temperature parameter collected by the fourth sensor; determine a water temperature correction coefficient based on the water temperature parameter; the water temperature correction coefficient is used to compensate the influence of temperature on the water density; determine the water density based on the pure water standard density, the water quality density correction coefficient, and the water temperature correction coefficient.

[0020] In the above implementation process, the water temperature correction coefficient is determined in combination with the water temperature parameter collected by the fourth sensor, the water density is calculated based on the pure water standard density, the water quality density correction coefficient, and the water temperature correction coefficient, the influences of temperature and water quality on the water density are compensated, the water level calculation precision based on weight is further improved, and stable high-precision detection performance of the device in a complex environment such as temperature and humidity change is ensured.

[0021] The third aspect of the embodiment of the present application provides a computer readable storage medium, which stores computer instructions, and the computer instructions are executed by a processor to implement the steps of the method in any of the second aspect.

[0022] The fourth aspect of the embodiment of the present application provides a computer program product, which includes a computer program, and the computer program is executed by a processor to implement the method in any of the second aspect. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments of the present application. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope, and for those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0024] Figure 1 A structure diagram of a capacitive water level detection device provided by the embodiment of the present application; Figure 2 A side view of a humidifier product provided by the embodiment of the present application; Figure 3 A structure diagram of a water level detection device provided by the embodiment of the present application; Figure 4 Another structure diagram of a water level detection device provided by the embodiment of the present application; Figure 5 Another structure diagram of a water level detection device provided by the embodiment of the present application; Figure 6 Another structure diagram of a water level detection device provided by the embodiment of the present application; Figure 7 Another structure diagram of a water level detection device provided by the embodiment of the present application. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application.

[0026] It should be noted that similar reference numerals and letters represent similar items in the drawings below, and therefore, once an item is defined in one drawing, it need not be further defined and explained in subsequent drawings. Meanwhile, in the description of the present application, the terms "first", "second", and the like are only used for distinguishing description, and cannot be understood as indicating or implying relative importance.

[0027] In the related art, water level detection is mainly performed through the following logics: (1) Float type water level measurement: the float is lifted by the buoyancy generated when the float is put into water, and the water level height is observed according to the position of the float; (2) Ultrasonic wave type water level measurement: the principle that a sound wave is reflected when it encounters different density media in medium transmission is used to detect the water level change by abutting the probe of the ultrasonic wave sensor against the inner cavity wall of the humidifier; (3) Capacitive type water level detection: whether there is liquid in the container or whether the liquid reaches a certain height is determined by detecting the change of the capacitance. Refer to Figure 1 , Figure 1 A capacitive type water level detection device structure diagram provided in the embodiments of the present application; (4) Weighing type water level detection: the water level gravity is detected by using a gravity sensor, which is converted into the corresponding liquid volume, and then the height of the water level is calculated.

[0028] However, the related art has the following defects: For the float type: the measurement accuracy is poor due to interference such as dirt, loose installation position, and the like after long time use, and the structure requirement is high, and the reliability is not good; the mechanical float needs to be observed by the human eye to determine the liquid level height, and automatic detection cannot be realized, and the user experience is not good; For the ultrasonic wave sensor technology: the transmission speed is different in different medium liquids, and the detection result will be different when the oil and the like are added in water; in addition, it is greatly affected by water fluctuation, and the water in the water tank will fluctuate violently when water is added or the water tank is moved, and at this time, the ultrasonic wave sensor detection is easy to produce large error. If detection is performed after the level is stable, a long time needs to be waited, which affects the timeliness of the user to obtain the water level information, and reduces the user experience. The installation position requirement is high, the probe needs to be accurately abutted against the inner cavity wall of the humidifier, and the improper installation position may affect the detection accuracy.

[0029] For capacitive type: due to the size limitation of capacitive sensor contacts, it is difficult to achieve millimeter level detection accuracy; capacitive liquid level detection chip usually needs to be calibrated accurately before use to ensure the accuracy of liquid level detection, which increases the production and maintenance cost; in addition, it is greatly affected by medium, the measurement principle of capacitive water level sensor is based on the dielectric constant of water, when there are impurities, salt or other substances in water, the dielectric constant of water will change, resulting in measurement error. For example, in seawater or water containing a large amount of minerals, the measurement result may have a large deviation from the actual water level; the edge effect error is large, in capacitive water level sensor, edge effect is inevitable. When the water level is close to the edge of the sensor or in some irregularly shaped containers, the electric field distribution will become complex, the capacitance change at the edge is different from the ideal situation, resulting in reduced measurement accuracy, especially when measuring low water level or small range water level change, this error may be more obvious; temperature stability problem, temperature change will have multiple effects on capacitive water level detection. On the one hand, temperature change will cause the physical properties of sensor materials to change, such as thermal expansion and contraction, which will change the electrode spacing and affect the capacitance value; humidity influence, in high humidity environment, water vapor may condense on the surface of the sensor, which not only changes the capacitance value of the sensor, but also may cause electrode short circuit or leakage, etc., affecting the normal work of the sensor. In addition, long-term use in high humidity environment may also cause the internal electronic components of the sensor to be damp, reducing its performance and service life; high installation requirement, the installation position and method of capacitive water level sensor have important influence on the measurement result. The sensor must be parallel to the container wall, and the installation position should avoid the impact of water flow, vortex, etc. in the container, otherwise it will affect the electric field distribution and cause inaccurate measurement.

[0030] For weighing type: when the difference between full water weight and lack of water weight is large, the detection accuracy difference is large, it is difficult to achieve accurate detection of full water and lack of water.

[0031] In view of the above any defects, the embodiment of the application provides a water level detection scheme which integrates multi-sensor cooperation, isolated cavity water stabilization and blind area avoidance. As shown in Figure 2 , Figure 2 A humidifier product side view is provided for the embodiment of the application. The humidifier product is composed of two parts, a head and a body. The body is internally provided with a water body with a height of H2, and the air above the water body has a height of H1. Referring to Figures 3-4 , Figure 3 A water level detection device structure diagram is provided for the embodiment of the application, Figure 4Another water level detection device structure diagram provided by the embodiment of the application. In order to measure the height of the water body, the control unit and the TOF sensor module are added to the head part, the isolation cavity is placed in the body, and the absorption pad for absorbing the TOF light signal is placed below the isolation cavity. Specifically, the TOF sensor is designed and placed in the head, which is composed of a transmitting end TX and a receiving end RX. The TX is used to transmit a light signal of a specific wavelength, and the RX is used to receive the light signal emitted by the TX and reflected by the obstacle. The control unit is designed and placed in the head, which is used to process the distance information collected by the TOF sensor. In addition, the isolation cavity is designed, that is, a separate water level cavity is provided to isolate the water body outside the cavity. This can greatly weaken the influence of the TOF sensor on the distance collection through the light signal when the water is added, discharged or the water surface is subjected to external force. The cross section of the water body in the horizontal direction of the isolation cavity is relatively small, and the inner wall of the isolation cavity is isolated from the external water body, which can improve the stability of the water surface in the cavity. In addition, in order to ensure that the water level in the isolation cavity and the outside is consistent during the water adding and discharging process, and there is no difference in water level due to different air pressures, a pressure guide groove as shown in Figure 4 is designed, that is, a micro groove is opened at the sealing part connecting the isolation cavity and the head. On the one hand, the micro groove can make the air in the isolation cavity quickly the same as the air outside the cavity, so as to ensure the consistency of the air pressure; on the other hand, the micro groove has a small opening, and has little influence on the maximum water level height.

[0032] Referring to Figure 5 , Figure 5 Another water level detection device structure diagram provided by the embodiment of the application. The TOF sensor emits a light signal, which is irradiated to the water surface at T1 time, and is received by RX after being reflected by the water surface at T2 time. Since the water level in the isolation cavity is consistent with the water level outside the cavity, the light signal reflected by the water surface can be received by the RX, and the water level in the water tank can be determined according to the time difference between T1 and T2.

[0033] Referring to Figure 6 , Figure 6 Another water level detection device structure diagram provided by the embodiment of the application. The TOF sensor emits a light signal, which is irradiated to the water surface at T1 time, and is received by RX after being reflected by the water surface at T2 time. Since = constant C, according to which the water level height is shown as follows, and the water level is shown in percentage (percentage calculation formula: ): Formula 1; In formula 1, V is the speed of light propagation in air.

[0034] Referring to Figure 7 , Figure 7 Another water level detection device structure diagram provided by the embodiment of the application. The application places a sensor for measuring water quality TDS, a temperature sensor, and a weighing sensor located below the water tank at the bottom of the water tank. The TDS sensor is used to detect the quality of the water, i.e., the degree of purity of the water. When the water contains different components and different concentrations of inorganic salts, it will affect the signal reflection intensity of TOF. The higher the TDS value, the more impurities in the water, which will increase the absorption and scattering of the water to the TOF signal, resulting in a weaker signal received by the receiving end of the TOF sensor, which is not conducive to distance measurement. To solve this problem, the application proposes to use different transmission powers for TOF according to different TDS ranges of the water, i.e., the higher the TDS, the greater the power of the TOF sensor transmission circuit, so as to weaken the weakening effect of TDS on the TOF transmission signal intensity. The definition formula is as follows: Formula 2; In formula 2, is the transmission power of the TOF sensor, is the transmission power of the TOF sensor that can effectively detect the water level height when the water is standard pure water, is the water quality TDS value correction coefficient obtained by the TDS sensor, and the correction coefficient obtained after conversion, and the water quality TDS detection value are negatively related, i.e. , is the TDS value of the water measured by the TDS sensor. According to the actual test TDS value, different segments are divided, and the value is confirmed, so that the transmission power of the transmission pipe can be confirmed, and the adverse effect of different water qualities on the signal collection of the receiving end of the TOF sensor can be greatly weakened.

[0035] Since the TOF sensor has a minimum measurement blind area, i.e., when the TOF sensor is too close to the water surface position, the distance between the TOF sensor and the water surface cannot be accurately obtained due to the too fast propagation speed of light, which greatly limits the requirement of the installation height of the TOF sensor from the water surface. To solve this problem, the application also designs a weighing sensor, which is located at the bottom of the water tank and can obtain the weight of the water in the water tank by weighing, and then convert the volume and height of the water tank, i.e. , wherein is the weight of the water, is the cross-sectional area of the water tank bottom, is the height of the water, is the density of the water. The density of pure water is a constant When the water contains impurities, also changes, and the density of the water will increase, in order to reduce the impact of changes on the water level height measured, the following formula 3 is used: Formula 3; In formula 3, is the water density correction coefficient obtained by the TDS sensor measuring the water quality TDS value, and the water quality TDS detection value is positively correlated, that is , and then . From the above data, the water level height is . In order to weaken the adverse effects of water temperature changes on water density, the temperature sensor is designed, the temperature value measured by the temperature sensor is , the actual measured compensated water density and the relationship between the pre-compensation water density is , wherein is the temperature correction coefficient, which is obtained according to the actual test value. When the temperature is greater than 4℃, the higher the water temperature, the lower the water density, that is , the correction coefficient under different water temperature can be obtained through experimental test, and then the water level height is obtained.

[0036] For the TOF sensor, due to the fast speed of light, if the distance between the measured target and the TOF emission and receiving sensor is too close, the light photon round trip time is extremely short, and the distance between the measured object and the TOF sensor cannot be accurately tested, therefore, the TOF module has a blind area for close distance test. In order to solve this problem, the present application proposes: Assuming that the blind distance of the TOF sensor is , in order to avoid using the blind area of the TOF test, a safety distance is added on the basis of the blind distance , that is, when the distance between the liquid surface and the blind area is , the TOF module test liquid level height is started, accordingly, the liquid level weight at a height of is , wherein is the density of the liquid. Assuming that the total weight of the device when full of liquid is , the effective measurement liquid level percentage of the weighing sensor is , that is, the liquid level weight tested by the weighing sensor is lower than After that, the TOF sensor is started again to measure the liquid level height, so as to effectively avoid the test blind area of the TOF sensor.

[0037] In addition, compared with the full water condition, when the water height is lowered to a very low level, the weight of the water is greatly reduced, which will cause the weight measured by the weighing sensor to deviate more, and the water height cannot be accurately measured. At this time, the TOF sensor is far away from the water surface position, and the measurement result of the TOF sensor is more accurate. Therefore, the above scheme is designed in combination with the shortcomings of the TOF sensor in close-range measurement and the shortcomings of the weighing sensor in measuring light water body with large error. When the water level is high, the measurement result of the weighing sensor is used as the reference; when the water level is low, the measurement result of the TOF sensor is used as the reference. Such design has the following advantages: The defects of the two measurement methods are reasonably avoided, and the measurement accuracy can be effectively improved; the weighing sensor only needs to select a high water level range, and does not need other range sensors, so that the cost can be reduced; within the full range, as long as the measurement blind area of the TOF sensor is exceeded, the TOF sensor can be used for measurement, and the accuracy can reach millimeter level. The use of two sensors improves the robustness of water level measurement, avoids false detection when a single sensor fails, and effectively identifies water shortage and other fault conditions.

[0038] Based on this, the water level detection device provided by the embodiments of the present application comprises: The body mechanism comprises an isolated cavity for water storage and an outer cavity area; the water surface of the isolated cavity is consistent with the water surface of the outer cavity area; the isolated cavity comprises a water storage part and a non-water storage part; The head mechanism is installed on the body mechanism; the head mechanism comprises a first sensor and a control device; the first sensor is used for emitting and receiving test signals to the water surface of the isolated cavity; and the control device is used for determining the water level height of the water storage part according to the transmission time of the test signal in the non-water storage part and the total height of the water level detection device.

[0039] It should be noted that the body mechanism and the head mechanism are detachably connected, and the body mechanism serves as a carrier for water storage and auxiliary detection, and comprises an isolated cavity for water storage and an outer cavity area. The water storage part refers to the area containing water, and the non-water storage part refers to the air area above the water. If the isolated cavity is filled with water, there is no non-water storage part.

[0040] The nose mechanism is installed on the top of the body mechanism and is responsible for signal transmission, reception and data processing, including but not limited to the first sensor and the control device. The first sensor is a TOF (Time of Flight) sensor module, which has a transmitting end and a receiving end. It can transmit test signals to the non-water storage part of the isolated cavity (the test signal is a specific wavelength of light signal, such as near-infrared light. The light signal first passes through the air in the non-water storage part, and then reflects on the water surface to avoid direct contact with the water, which can cause the sensor to corrode, and at the same time ensure the stability of the signal transmission path). The control device uses an MCU (Micro Control Unit, such as STM32 series chip) with built-in data processing algorithm, which can receive the test signal transmission time collected by the first sensor, and calculate the water level height of the water storage part combined with the pre-stored total height of the water level detection device. The calculation logic is: total height = non-water storage part height + water storage part height. After calculating the height of the non-water storage part by the test signal transmission time, the height of the water storage part (i.e. the water level height) can be deduced.

[0041] Optionally, the bottom of the isolated cavity is provided with a flow guide groove, and the connection between the isolated cavity and the nose mechanism is provided with a pressure guide groove. The flow guide groove and the pressure guide groove are used to control the height of the water surface in the isolated cavity to be consistent with the height of the water surface outside the cavity.

[0042] It should be understood that, in order to ensure that the water level height of the isolated cavity is consistent with the water level height outside the cavity (avoiding water level difference caused by air pressure and poor flow), a flow guide groove is provided at the bottom of the isolated cavity, and a pressure guide groove is provided at the connection between the isolated cavity and the nose mechanism. The flow guide groove is a groove through the bottom of the isolated cavity, which can make the water in the cavity outside the cavity and the water in the isolated cavity flow quickly, ensure that the water level of the two changes synchronously, and avoid water level lag caused by adding water and draining water. The pressure guide groove is a micro-sized groove, which can make the air in the isolated cavity and the outside air quickly communicate, balance the air pressure inside and outside the cavity, and at the same time, due to the extremely small size of the groove, it will not affect the highest water level height in the isolated cavity (avoiding water overflow from the pressure guide groove).

[0043] In specific implementation, the nose mechanism corresponds to the nose in Figure 2 ; the control device corresponds to the control unit in Figure 3 , Figure 4 , Figure 6 , Figure 7 ; the first sensor corresponds to the TOF sensor in Figure 3 , Figure 4 , Figure 6 , and corresponds to the TOF Sensor in Figure 7 ; the pressure guide groove and the isolated cavity correspond to Figure 4The bottom flow guide groove in the water level detection device corresponds to the flow guide groove in the body mechanism. Figure 5 The bottom flow guide groove in the water level detection device corresponds to the flow guide groove in the body mechanism.

[0044] Optionally, the body mechanism further comprises an absorbing pad, which is arranged below the isolated cavity and has a horizontal cross-sectional area greater than that of the water body in the isolated cavity, and the absorbing pad is used to absorb the test signal emitted by the first sensor and not reflected by the water surface.

[0045] It should be noted that, in order to avoid false detection caused by the test signal emitted by the first sensor not being reflected by the water surface and directly irradiating to the bottom of the body and then being reflected back to the receiving end (for example, when there is no water, the optical signal is misjudged as water surface reflection by being reflected by the bottom), an absorbing pad is arranged below the isolated cavity in the body mechanism: The absorbing pad is made of black light-shielding material (such as black foam or black rubber), which can completely absorb or greatly absorb the optical signal not reflected by the water surface. The absorbing pad has a horizontal cross-sectional area greater than that of the water body in the isolated cavity, so as to ensure that the optical signal emitted by the first sensor (even if there is a slight deviation) can be covered by the absorbing pad without light leakage reflection.

[0046] In a specific implementation, the absorbing pad corresponds to the TOF signal absorbing pad in the water level detection device. Figure 5

[0047] It can be understood that, by arranging the absorbing pad below the isolated cavity and having a horizontal cross-sectional area greater than that of the water body in the cavity, the test signal emitted by the first sensor and not reflected by the water surface can be completely absorbed, the signal reflected by the bottom can be avoided from being mis-received, interference factors can be further eliminated, the accuracy of the detection data of the first sensor can be ensured, and the detection stability of the device can be improved.

[0048] In this embodiment, the water level detection based on the test signal transmission time and the total height of the device is realized by the first sensor of the head mechanism and the control device, which provides a device basis for precise, anti-interference and stable water level measurement.

[0049] On the basis of any of the above embodiments, the body mechanism further comprises a second sensor installed in the body mechanism and used to collect water quality state parameters of the water body.

[0050] ​It should be noted that, in order to solve the influence of water quality change on the signal strength of the first sensor (for example, the increase of impurities in water will absorb and scatter light signals, resulting in weakening of the signal at the receiving end), a second sensor is installed in the body mechanism at a position extending into the water body. Optionally, the second sensor is a TDS (Total Dissolved Solids) sensor, and the second sensor is used to collect water quality state parameters (i.e., TDS value, unit: mg / L, water quality state parameters are used to represent the content of inorganic salts and impurities in water) of the water body in real time. The second sensor needs to be completely immersed in the water body in the body mechanism to ensure that the collected water quality parameters are consistent with the water quality parameters of the water body in the isolated cavity (because the water level in the isolated cavity is consistent with the water level outside the cavity, the water quality parameters are also consistent), avoiding collection deviation.

[0051] In a specific implementation, the second sensor corresponds to a 1 water quality TDS sensor in Figure 7

[0052] In this embodiment, the second sensor in the body mechanism collects water quality state parameters of the water body, providing a basis for detection correction for water quality changes, so that the device can still maintain high-precision detection through correction when the water quality changes (such as adding essential oils, mosquito repellent, etc.), ensuring the stability of the detection result.

[0053] On the basis of any of the above embodiments, the body mechanism further includes a third sensor installed below the body mechanism for collecting the total weight of the water level detection device and the internal water body.

[0054] It should be noted that, in order to avoid the measurement blind area of the first sensor (TOF sensor has a minimum detection distance, when the water surface is too close to the sensor, the light signal round trip time is too short, and the distance cannot be accurately calculated), a third sensor is installed below the body mechanism (such as the bottom support). The third sensor is a weighing sensor (such as a strain gauge type weighing sensor), and the third sensor is used to collect the total weight of the water level detection device and the internal water body (i.e., the total mass of the body mechanism, the head mechanism, all sensors and the internal water body corresponds to the gravity value).

[0055] In a specific implementation, the third sensor corresponds to a 3 weighing sensor in Figure 7

[0056] In this embodiment, the third sensor below the body mechanism collects the total weight of the device and the internal water body, and forms a complement with the first sensor. When the first sensor is in the measurement blind area, the water level is calculated through the weight data, effectively expanding the measurement range and improving the overall robustness of the device.

[0057] On the basis of any of the above embodiments, the body mechanism further includes a fourth sensor installed in the body mechanism for collecting water temperature parameters.​​

[0058] It should be noted that, in order to solve the influence of water temperature change on water density (the density of water changes with temperature, for example, the density of pure water is 1 g / cm 3 when the temperature rises, the density decreases, which will cause errors in calculating the water level by weighing method), a fourth sensor is installed in the body mechanism at a position extending into the water body. Optionally, the fourth sensor is an NTC (Negative Temperature Coefficient) temperature sensor: the fourth sensor is used to collect the temperature parameter (unit: ℃) of the water body in real time. The fourth sensor is adjacent to but not in contact with the second sensor, so as to ensure that the collected water temperature corresponds to the same water body as the water quality parameter collected by the second sensor, and at the same time avoid signal interference between the sensors (such as the influence of the electrode signal of the TDS sensor on the temperature sensor).

[0059] In a specific implementation, the fourth sensor corresponds to the 2 temperature sensor in Figure 7 .

[0060] In this embodiment, the fourth sensor in the body mechanism collects the temperature parameter of the water body, which provides compensation basis for the influence of water temperature change on water density, so that the device can still accurately calculate the water density when the water temperature fluctuates, thereby ensuring the accuracy of water level calculation based on weight, reducing the interference of environmental temperature change on the detection result, and enhancing the stability of the device in different temperature environments.

[0061] In addition, the embodiment of the present application also provides a water level detection method based on the above water level detection device, which is applied to the control device of the head mechanism; the method comprises: If the distance between the water surface of the isolated cavity and the first sensor exceeds the preset distance threshold, the first sensor is instructed to emit a test signal to the water surface of the isolated cavity; the isolated cavity is located in the body mechanism, the head mechanism is installed on the body mechanism, the body mechanism further comprises an area outside the cavity, the height of the water surface of the isolated cavity is consistent with the height of the water surface of the area outside the cavity, the isolated cavity comprises a water storage part and a non-water storage part, the first sensor is located in the head mechanism, and the preset distance threshold is determined based on the measurement blind area distance of the first sensor; It should be noted that, when the distance between the water surface of the isolated cavity and the first sensor exceeds the preset distance threshold, it means that the water surface is far away from the sensor, which exceeds the measurement blind area of the first sensor, and the first sensor can accurately detect.

[0062] The purpose of designing the preset distance threshold is to avoid the blind area of the first sensor. Assuming that the minimum measurement blind area distance of the first sensor is (For example, the minimum measurement blind zone distance is 2cm). To avoid accidental switching due to minor water surface ripples, an additional safety distance is set. (e.g., 10mm), then the preset distance threshold = (e.g., 3cm). The control device uses the previously calibrated distance between the first sensor and the bottom of the machine, combined with historical detection data, to determine whether the current distance between the water surface and the first sensor exceeds the threshold. If it exceeds the threshold, the control device sends a command to the first sensor, instructing its transmitter to emit a test signal (e.g., a light signal) towards the water surface.

[0063] Optionally, the isolated cavity is located in the fuselage mechanism, the head mechanism is mounted on the fuselage mechanism, the fuselage mechanism also includes an area outside the cavity, the bottom of the isolated cavity is provided with a flow guide groove, and the connection between the isolated cavity and the head mechanism is provided with a pressure guide groove. The flow guide groove and the pressure guide groove are used to control the water level in the isolated cavity to be consistent with the water level in the area outside the cavity. The isolated cavity includes a water-filled part and a water-free part. The first sensor is located in the head mechanism, and the preset distance threshold is determined based on the measurement blind zone distance of the first sensor.

[0064] Obtain the transmission time of the test signal in the unwater-filled section; As an example, the receiving end of the first sensor receives the light signal reflected from the water surface, and the control device records the time T1 from the transmitting end to the water surface and the time T2 from the water surface to the receiving end. Since the distance between the transmitting end and the receiving end is extremely close (on the millimeter level), the transmission time T can be approximated as T = T1 + T2.

[0065] Obtain the total height of the water level detection device; Based on the transmission time and the total height of the device, the water level in the water storage section of the isolated cavity is determined.

[0066] It should be noted that obtaining the total height of the device can refer to obtaining the pre-stored total height of the device, or it can refer to obtaining the total height of the device in real time.

[0067] As an example, the control device first obtains the preset total height H of the water level detection device. 总 (The height of the unfilled portion is determined by mechanical calibration before leaving the factory, such as 30cm). Then, the height of the unfilled portion is calculated based on the transmission time. The height of the filled portion (i.e., the actual water level) is obtained by subtracting the height of the unfilled portion from the total height of the device. Specifically, let the speed of light in air be V (approximately 3 × 10⁻⁶). 8 If the transmission speed is m / s and the transmission time is T, then the height H of the unfilled portion is... 空 =(V×T) / 2 (divided by 2 because of signal round trip); the total height of the device is H. 总 Then the height H of the water storage section水 =H 总 -H 空 .

[0068] In this embodiment, when the water surface of the isolated cavity is more than a preset threshold determined based on a measurement blind area from the first sensor, a test signal is transmitted by the first sensor, the water level is calculated by the signal transmission time and the total height of the device, the advantage of fast measurement of the first sensor is fully played, real-time detection is realized, and water level changes can be timely reflected.

[0069] On the basis of any of the above embodiments, the method further comprises: In the case where the distance does not exceed the preset distance threshold, the total weight of the water level detection device and the internal water body collected by the third sensor is obtained; The bottom cross-sectional area of the water level detection device and the water density of the water body in the isolated cavity are obtained; Based on the bottom cross-sectional area, the water density, and the weight, the water level height of the water storage part is determined.

[0070] It should be understood that in the case where the distance between the water surface of the isolated cavity and the first sensor does not exceed the preset distance threshold, the first sensor (such as a TOF sensor) is invalid for detection, and the third sensor (such as a weighing sensor) needs to be enabled.

[0071] The total weight refers to the total weight of the fuselage mechanism, the isolated cavity, the water body outside the cavity, and all components. The total weight collected by the third sensor is transmitted to the control device.

[0072] The bottom cross-sectional area of the water level detection device refers to the horizontal cross-sectional area of the area inside the fuselage mechanism for water storage (i.e., the sum of the cross-sectional area of the isolated cavity and the cross-sectional area of the area outside the cavity, because the water levels of the two are consistent, the total water storage volume = bottom cross-sectional area x water level height). Alternatively, the bottom cross-sectional area of the water level detection device is a inherent property of the device, which is calibrated at the factory and stored in the control device, and does not need to be collected in real time.

[0073] The water density of the water body in the isolated cavity refers to the actual water density under the current working condition (considering the influence of water quality and temperature), rather than the standard density. The water density directly affects the conversion accuracy of weight-volume.

[0074] Specifically, based on the formula weight = density x volume, the water body weight is first calculated by the total weight, then converted to water body volume, and finally the water level height is calculated by volume = cross-sectional area x height. The control device needs to call the preset empty weight of the device (M 空 , i.e., the weight of the fuselage mechanism, the nose mechanism, each sensor, etc. without water body), calculate the water body weight M 水 =M 总 -M空 For example, assuming the water density is p, the bottom cross-sectional area is S, and the water volume is V 水 =M 水 / p; then the water level H 水 =V 水 / S=M 水 / (S x p).

[0075] In this embodiment, when the distance between the water surface of the isolated cavity and the first sensor does not exceed the preset threshold, the water level is calculated based on the total weight collected by the third sensor, combined with the bottom cross-sectional area of the device and the water density, fully utilizing the advantage of the weighing method in close-range detection, making up for the deficiency of the TOF technology in the blind area, and realizing high-precision detection in the blind area.

[0076] On the basis of any of the above embodiments, the water density is obtained by the following steps: Obtaining the water quality state parameter of the water body in the isolated cavity collected by the second sensor; Determining the corresponding water quality density correction coefficient based on the water quality state parameter; the water quality density correction coefficient is positively correlated with the water quality state parameter; Determining the water density based on the preset pure water standard density and the water quality density correction coefficient.

[0077] It should be noted that the water quality state parameter is obtained because impurities such as inorganic salts in water can increase the density of water, such as the density of seawater being greater than that of fresh water, and the density needs to be corrected by the TDS value of the water quality state parameter.

[0078] The water quality density correction coefficient is used to compensate for the influence of the TDS value on the water density, and it is positively correlated with the TDS value - that is, the higher the TDS value (the more impurities), the greater the water quality density correction coefficient, because impurities can increase the water density. For example, by experimentally calibrating the correction coefficient corresponding to different TDS values, specifically, the water quality density correction coefficient KTDS2 = actual density / pure water standard density. For example: when TDS = 0 (pure water), the water quality density correction coefficient KTDS2 = 1 (density is 1 g / cm 3 ).

[0079] The preset pure water standard density (p0) refers to the density of pure water at 4℃ under standard atmospheric pressure, which is usually 1 g / cm 3 .

[0080] Optionally, the water density is determined based on the product of the pure water standard density p0 and the water quality density correction coefficient KTDS2.

[0081] In the embodiment, the water quality density correction coefficient of positive correlation is determined according to the water quality state parameter collected by the second sensor, the water density is calculated in combination with the standard density of pure water, the influence of water quality change on the water density is effectively compensated, the water level calculation based on weight is more accurate, and the detection precision and anti-interference ability of the device under the condition of water quality change are enhanced.

[0082] On the basis of any of the above embodiments, the water density is determined based on the preset standard density of pure water and the water quality density correction coefficient, and the method comprises: obtaining a water body temperature parameter collected by a fourth sensor; determining a corresponding water temperature correction coefficient based on the water body temperature parameter; the water temperature correction coefficient is used to compensate the influence of temperature on the water body density; determining the water density based on the standard density of pure water, the water quality density correction coefficient, and the water temperature correction coefficient.

[0083] It should be noted that since temperature affects water density, the embodiment further compensates on the basis of water quality correction to solve the problem of temperature affecting water density. Generally, the density of water is the largest when the water temperature is 4℃, and the density decreases when the water temperature is higher or lower than 4℃.

[0084] Water temperature correction coefficient K temp is used to compensate the influence of temperature on the water body density. When the water temperature is greater than 4℃, the higher the water temperature, the smaller K temp , such as K temp =1 when the water temperature is 4℃, K temp =0.997 when the water temperature is 25℃, and K temp =0.958 when the water temperature is 100℃. When the water temperature is less than 4℃, the lower the water temperature, the smaller K temp , such as K temp =0.9998 when the water temperature is 0℃. Alternatively, the water temperature correction coefficient is calibrated based on the density-temperature characteristic curve of water, the characteristic curve is measured by experiment, and is pre-stored in the control device.

[0085] In a specific implementation, the water density is calculated by the following formula 4: ρ=ρ0×KTDS2×K temp Formula 4; In formula 4, ρ is the water density, ρ0 is the standard density of pure water, KTDS2 is the water quality density correction coefficient, and K temp is the water temperature correction coefficient.

[0086] In the embodiment, the water temperature correction coefficient is determined in combination with the water temperature parameter collected by the fourth sensor, the water density is calculated in combination with the pure water standard density and the water quality density correction coefficient, the influences of the temperature and the water quality on the water density are compensated, the water level calculation precision based on the weight is further improved, and it is ensured that the device still has stable and high-precision detection performance in a complex environment such as temperature and humidity change.

[0087] Based on the method in any of the above embodiments, the application further provides a computer storage medium, the storage medium storing a computer program, the computer program being executable by a processor to execute the method in any of the above embodiments.

[0088] Based on the method in any of the above embodiments, the application further provides a computer program product, the computer program product comprising one or more computer programs or instructions. The computer programs or instructions can be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium. The computer programs are executable by a processor to implement the method in any of the above embodiments.

[0089] In several embodiments provided in the application, it should be understood that the disclosed apparatus and method can also be implemented by other means. The apparatus embodiments described above are only schematic, for example, the flowcharts and block diagrams in the drawings show possible implementation architectures, functions and operations of the apparatus, method and computer program product according to the embodiments of the application. In this regard, each block in the flowcharts or block diagrams can represent a module, a program segment or a part of code, which contains one or more executable instructions for implementing the specified logic function. It should also be noted that in some alternative implementations, the functions noted in the blocks can occur in a different order than that noted in the drawings. For example, two consecutive blocks can actually be executed substantially in parallel, and sometimes they can be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and the combination of blocks in the block diagrams and / or flowcharts, can be implemented by a dedicated hardware-based system for implementing the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0090] In addition, each functional module in the embodiments of the application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0091] If the functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application essentially or the parts of the prior art that make contributions or parts of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various media that can store program codes.

[0092] The above merely provides an example of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application. It should be noted that similar reference numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0093] The above merely provides an example of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application. It should be noted that similar reference numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0094] It should be noted that, in the present document, the relationship terms such as first and second are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the processes, methods, articles or devices including a series of elements not only include those elements, but also include other elements not explicitly listed or inherent to such processes, methods, articles or devices. Without more limitations, the element defined by the statement "including a" does not exclude the presence of another identical element in the process, method, article or device including the element.

Claims

1. A water level detection device, characterized in that, include: The fuselage structure includes an isolated cavity for water storage and an outer region outside the cavity; the water level in the isolated cavity and the water level in the outer region outside the cavity are at the same height; the isolated cavity includes a water-storing part and a non-water-storing part; The head mechanism is mounted on the body mechanism; the head mechanism includes a first sensor and a control device; the first sensor is used to transmit and receive test signals to the water surface of the isolated cavity; the control device is used to determine the water level of the water-filled section based on the transmission time of the test signal in the non-water-filled section and the total height of the water level detection device.

2. The apparatus according to claim 1, characterized in that, The fuselage structure also includes a second sensor, which is installed inside the fuselage structure and is used to collect water quality parameters of the water body.

3. The apparatus according to claim 1, characterized in that, The fuselage structure also includes a third sensor, installed below the fuselage structure, for collecting the total weight of the water level detection device and the internal water.

4. The apparatus according to claim 1, characterized in that, The fuselage structure also includes a fourth sensor, which is installed inside the fuselage structure and is used to collect water temperature parameters.

5. A water level detection method based on the water level detection device according to any one of claims 1-4, characterized in that, The method is applied to a control device for a machine head mechanism; the method includes: If the distance between the water surface of the isolated cavity and the first sensor exceeds a preset distance threshold, the first sensor is instructed to emit a test signal toward the water surface of the isolated cavity. The isolated cavity is located in the fuselage mechanism, the head mechanism is mounted on the fuselage mechanism, and the fuselage mechanism also includes an area outside the cavity. The water surface of the isolated cavity is at the same height as the water surface of the area outside the cavity. The isolated cavity includes a water-filled part and a water-free part. The first sensor is located in the head mechanism, and the preset distance threshold is determined based on the measurement blind zone distance of the first sensor. Obtain the transmission time of the test signal in the unwater-filled section; Obtain the total height of the water level detection device; Based on the transmission time and the total height of the device, the water level in the water storage section of the isolated cavity is determined.

6. The method according to claim 5, characterized in that, The method further includes: If the distance does not exceed the preset distance threshold, the total weight of the water level detection device and the water inside it is obtained by the third sensor. Obtain the bottom cross-sectional area of ​​the water level detection device and the water density of the water in the isolated cavity; The water level of the water storage section is determined based on the bottom cross-sectional area, the water density, and the weight.

7. The method according to claim 6, characterized in that, The water density is obtained through the following steps: Obtain the water quality status parameters of the water body inside the isolated cavity collected by the second sensor; A corresponding water quality density correction coefficient is determined based on the water quality state parameters; the water quality density correction coefficient is positively correlated with the water quality state parameters. The water density is determined based on the preset standard density of pure water and the water density correction coefficient.

8. The method according to claim 7, characterized in that, The determination of the water density based on the preset pure water standard density and the water quality density correction coefficient includes: Acquire water temperature parameters collected by the fourth sensor; A corresponding water temperature correction coefficient is determined based on the water temperature parameters; the water temperature correction coefficient is used to compensate for the influence of temperature on water density. The water density is determined based on the standard density of pure water, the water density correction factor, and the water temperature correction factor.

9. A computer-readable storage medium, characterized in that, It stores computer instructions that, when executed by a processor, implement the steps of any of the methods described in claims 5-8.

10. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the method described in any one of claims 5-8.

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