Spherical temperature and humidity sensor, closed environment temperature and humidity measurement system and measurement method

Abstract

The application discloses a kind of spherical temperature and humidity sensor, closed environment temperature and humidity measuring system and measuring method, sensor includes: wireless communication module, for with the positioning base station in closed environment is carried out wireless communication and obtains first position information;IMU module, for the attitude information of sensor is collected to obtain the rolling speed variation of sensor and the second position information of sensor;Air pump, for external air is drawn into spherical shell interior;Temperature and humidity sensing module, for measuring temperature and humidity information according to air that air pump draws into spherical shell interior, and the working frequency of temperature and humidity sensing module and the air pumping rate of air pump change with the rolling speed variation of sensor;Master module, for obtaining accurate positioning information after fusing first position information and second position information, and for when sensor rolls to open environment, accurate positioning information and temperature and humidity information are transmitted to host computer by wireless communication module, to obtain the temperature and humidity of different positions in closed environment.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of sensors, and more particularly relates to a spherical temperature and humidity sensor, a closed environment temperature and humidity measurement system, and a measurement method. BACKGROUND

[0002] A sensor is an environmental perception device that can perceive various types of information about the surrounding environment, and convert the environmental information into an electrical signal through a certain means, and deliver the electrical signal to the remaining modules to realize information acquisition, conversion, storage, and control functions. The sensor is an important part of realizing automatic control and automatic detection. A temperature and humidity sensing module is a device that can perceive temperature and humidity information about the environment and convert it into an electrical signal of a certain size.

[0003] However, the current temperature and humidity sensing module can only measure the temperature and humidity in an open environment in real time and display it, and cannot automatically measure the temperature and humidity in a closed environment. When it is necessary to know the temperature and humidity information in a closed environment such as a tunnel or a closed metal pipeline, because such an environment is completely closed or semi-closed, real-time wireless communication cannot be used during work, real-time transmission and display cannot be achieved, and there is no mature solution on the market that can accurately measure the temperature and humidity information in a closed environment. SUMMARY

[0004] In view of the above defects or improvement needs of the prior art, the present application provides a spherical temperature and humidity sensor, a closed environment temperature and humidity measurement system, and a measurement method, which aims to solve the technical problem of being difficult to accurately measure the temperature and humidity information in a closed environment.

[0005] To achieve the above-mentioned purpose, according to a first aspect of the present application, a spherical temperature and humidity sensor is provided for measuring the temperature and humidity at different positions inside a closed environment. The sensor includes a spherical shell, a temperature and humidity sensing module, an IMU module, a wireless communication module, an air suction pump, a power module, and a main control module wrapped in the spherical shell. Wherein,

[0006] The wireless communication module is configured to communicate wirelessly with a positioning base station in the closed environment to enable the main control module to obtain first position information of the sensor;

[0007] The IMU module is configured to collect attitude information of the sensor to enable the main control module to obtain a rolling speed change of the sensor and second position information of the sensor;

[0008] The air suction pump is configured to suck external air into the interior of the spherical shell, and the air suction rate changes with the rolling speed change of the sensor. When the rolling speed increases, the air suction rate increases, and when the rolling speed decreases, the air suction rate decreases;

[0009] The temperature and humidity sensing module is used to measure the temperature and humidity information of the air drawn into the spherical shell by the air suction pump and store it into the main control module, and the working frequency of the temperature and humidity sensing module changes with the rolling speed of the sensor, when the rolling speed increases, the working frequency increases, and when the rolling speed decreases, the working frequency decreases.

[0010] The main control module is used to obtain accurate positioning information after fusing the first position information and the second position information, and is used to transmit the accurate positioning information and the temperature and humidity information to the external host computer through the wireless communication module when the sensor rolls into an open environment.

[0011] In one of the embodiments, the sensor further comprises a key module, the key module comprises a measurement key and a transmission key, when the measurement key is started, the sensor is in the working mode of measuring the positioning information and the temperature and humidity information in the sealed environment, when the transmission key is started, the sensor is in the working mode of sending the stored positioning information and the temperature and humidity information in the sealed environment to the host computer, and when the IMU module detects that the sensor no longer rolls, the measurement key is automatically turned off and the transmission key is started.

[0012] In one of the embodiments, the temperature and humidity sensing module comprises a stacked thermocouple structure layer, a chamber structure layer, an electrolyte structure layer, a voltage control circuit and a current detection circuit.

[0013] The chamber structure layer is provided with a first chamber and a second chamber, the thermocouple structure layer has a heating circuit adjacent to the first chamber and the second chamber, the electrolyte structure layer comprises an electrolyte, a top electrode arranged on the upper surface of the electrolyte, and a first bottom electrode exposed to the first chamber and a second bottom electrode exposed to the second chamber arranged on the lower surface of the electrolyte; the voltage control circuit is used to apply voltage between the first bottom electrode and the top electrode, and between the second bottom electrode and the top electrode, and the current detection circuit is used to detect the current between the second bottom electrode and the top electrode.

[0014] When the temperature and humidity sensing module works: the heating circuit is heated to a fixed temperature as the free end of the thermocouple, and the structure other than the heating circuit is used as the working end to detect the temperature of the air in the spherical shell and store it into the main control module; the air drawn into the spherical shell by the air suction pump first passes through the first chamber, and after the oxygen in the air is decomposed and consumed by the voltage control circuit, it enters the second chamber, in which the water vapor in the air is decomposed and consumed by the voltage control circuit to form a current which is measured by the current detection circuit and then fed back to the main control module, and the main control module calculates the humidity of the air in the spherical shell according to the detected current.

[0015] In one of the embodiments, the electrolyte is a zirconium oxide electrolyte.

[0016] In one of the embodiments, the master module is circular and matches the inner diameter of the spherical shell, and is placed at the inner diameter of the spherical shell, the power module is placed at one side of the master module, and the temperature and humidity sensing module, the IMU module, the wireless communication module and the air suction pump are placed at the other side of the master module and on the master module.

[0017] In one of the embodiments, the positioning base station in the sealed environment is a UWB base station, and the wireless communication module is used to transmit UWB signals with the UWB base station to calculate the first position information of the sensor.

[0018] In one of the embodiments, the spherical shell is made of high-temperature-resistant silica gel.

[0019] In one of the embodiments, the spherical temperature and humidity sensor is used to measure the temperature and humidity with the temperature greater than or equal to 150℃ and less than or equal to 300℃.

[0020] According to the second aspect of the present application, a sealed environment temperature and humidity measurement system is provided, which comprises a positioning base station arranged inside a sealed environment and the spherical temperature and humidity sensor described above.

[0021] According to the third aspect of the present application, a sealed environment temperature and humidity measurement method is provided, which arranges the sealed environment temperature and humidity sensor module system described above, rolls the spherical temperature and humidity sensor into the sealed environment to be measured, and receives the accurate positioning information and the temperature and humidity information on the host computer.

[0022] Overall, compared with the prior art, the above technical solutions conceived by the present application can achieve the following beneficial effects:

[0023] (1) The temperature and humidity sensor designed by the present application is spherical, and the spherical temperature and humidity sensor can roll in the sealed environment, and through the integrated temperature and humidity sensing module, IMU module and wireless communication module, the temperature and humidity at different positions can be measured and stored, and when the spherical temperature and humidity sensor rolls into an open environment, the stored positioning information and temperature and humidity information are sent to the host computer to obtain the temperature and humidity information at different positions inside the sealed environment.

[0024] (2) The spherical temperature and humidity sensor is also designed with an air suction pump, and the air suction rate of the air suction pump and the working frequency of the temperature and humidity sensing module are linked with the detection results of the IMU module, when the detection results of the IMU module show that the rolling speed of the spherical temperature and humidity sensor is slow, the air suction rate of the air suction pump and the working frequency of the temperature and humidity sensing module are appropriately reduced to save system energy consumption, and when the detection results of the IMU module show that the rolling speed of the spherical temperature and humidity sensor is fast, the air suction rate of the air suction pump and the working frequency of the temperature and humidity sensing module are appropriately increased to obtain more temperature and humidity information at different positions. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1is a closed environment temperature and humidity measurement system structure schematic diagram provided by the embodiment of the application;

[0026] Figure 2 is a spherical temperature and humidity sensor internal structure schematic diagram provided by the embodiment of the application;

[0027] Figure 3 is a spherical temperature and humidity sensor internal module connection schematic diagram provided by the embodiment of the application;

[0028] Figure 4 is a temperature and humidity sensing module internal structure schematic diagram provided by the embodiment of the application;

[0029] Figure 5 is a UWB ranging principle schematic diagram provided by the embodiment of the application;

[0030] Figure 6 is a TOA three-dimensional positioning algorithm schematic diagram provided by the embodiment of the application;

[0031] Figure 7 is a closed environment temperature and humidity measurement method flowchart provided by the embodiment of the application;

[0032] In all the drawings, the same reference signs are used to represent the same elements or structures, wherein:

[0033] 1, base station; 11, base station antenna; 12, base station controller; 2, spherical temperature and humidity sensor; 21, temperature and humidity sensing module; 211, first cavity; 212, second cavity; 213, heating circuit; 214, thermocouple circuit; 215, electrolyte; 216, current detection circuit; 217, voltage control circuit; 22, wireless communication module; 23, main control module; 24, air pump; 25, power module; 26, key module; 261, measurement key; 262, transmission key; 27, IMU module; 3, upper computer. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application is further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application. In addition, the technical features involved in each embodiment of the application described below can be combined with each other as long as they do not conflict with each other.

[0035] As Figure 1The structure diagram of the closed environment temperature and humidity measurement system in an embodiment is shown, which includes a positioning base station 1 arranged inside the closed environment, a spherical temperature and humidity sensor 2 and a host computer 3 arranged outside the closed environment. The closed environment is generally a tunnel, a metal pipeline or other high-temperature complex closed environment, and the temperature is as high as 150℃ or above, generally 150℃-300℃. The base station 1 is fixed at the edge of the environment to be measured.

[0036] The base station 1 is a movable base station, which is composed of a base station antenna 11 at the top and a base station controller 12 at the bottom. The base station antenna 11 is in a cylindrical shape, and the tip of the base station antenna 11 is in a hemispherical shape. The base station controller 12 is in a cuboid box shape. According to different positioning requirements, three or four base stations 1 are arranged. The base stations 1 are arranged at different positions according to the measurement environment and space, and the position of each base station 1 is recorded during operation. The movable base station is adopted to realize convenience and repeated use in multiple scenes. Different numbers of base stations are arranged under different positioning requirements. Generally, three base stations are arranged at appropriate positions in the closed environment in a two-dimensional positioning scene. Four or more base stations are arranged in a three-dimensional positioning scene. By skillfully arranging the base stations, the difficulty of position solving of the master module can be reduced, and the measurement accuracy can be improved. When arranging the base stations, the height difference of the Z axis needs to be ensured to ensure the accuracy on the Z axis.

[0037] The closed environment temperature and humidity measurement method is as follows: the spherical temperature and humidity sensor 2 is rolled into the closed environment to be measured. The spherical temperature and humidity sensor 2 rolls in the closed environment by relying on the spherical structure. The spherical temperature and humidity sensor 2 communicates with the positioning base station 1 to obtain positioning data, and also measures the temperature and humidity information at different positions while rolling. When the spherical temperature and humidity sensor 2 rolls to an open environment, the stored positioning information and temperature and humidity information are uploaded to the host computer 3. The accurate positioning information and temperature and humidity information are received on the host computer 3 to obtain the temperature and humidity at different positions in the closed environment.

[0038] The spherical temperature and humidity sensor 2 is a special structure designed by the present application for closed environment temperature and humidity measurement. The spherical temperature and humidity sensor is the main component of the system, which rolls in the complex environment by relying on the spherical external structure. The mass distribution of the sphere must be uniform, the center of gravity of the sphere is located at the center of the sphere, and the sphere structure is firm and will not deform due to rolling.

[0039] As shown in FIG. 1, the closed environment temperature and humidity measurement system includes a positioning base station 1 arranged inside the closed environment, a spherical temperature and humidity sensor 2 and a host computer 3 arranged outside the closed environment. Figure 2The internal structure of the spherical temperature and humidity sensor 2 in an embodiment is shown. It includes a spherical shell and functional modules inside the spherical shell. The spherical shell can be made of a layer of high-temperature-resistant silica gel, allowing the sensor to work in a high-temperature environment. The internal functional modules include a main control module 23 in the middle, with a power module 25 below and a temperature and humidity sensor module 21, a wireless communication module 22, a suction pump 24, and an IMU (Inertial Measurement Unit) module 27 on the upper side.

[0040] As shown in Figure 3 The connection diagram of the internal modules of the spherical temperature and humidity sensor is shown. The main control module 23 is the core component of the system and participates in the control and coordination of each module. Specifically, the main control module 23 is a circular sheet structure with a printed circuit board as the carrier, and the diameter of the printed circuit board is the same as that of the sphere. The circular printed circuit board is placed horizontally in the middle of the sphere at the diameter plane, and the main control module 23 is used to coordinate and control the operation of all modules inside the spherical temperature and humidity sensor 2. The power module 25 is responsible for providing power to the entire system, and the power is supplied to the remaining components after being converted and controlled by the DC-DC voltage of the main control module 23. Specifically, the power module 25 is in the shape of a hemisphere, and the diameter of the hemispherical battery is slightly smaller than that of the printed circuit board. The power module 25 is located directly below the main control module 23. The temperature and humidity sensor module 21 is controlled and coordinated by the main control module 23, and is used to measure environmental temperature information and humidity information. The wireless transmission module 22 is located on both sides of the suction pump 24, responsible for UWB communication ranging with the external base station 1, and the first position information of the spherical temperature and humidity sensor 2 is calculated by the main control module 23. The IMU module 27 is responsible for measuring the attitude information of the spherical temperature and humidity sensor 2, and the second position information of the spherical temperature and humidity sensor 2 is calculated by the main control module 23. The main control module 23 completes the data fusion of the first position information and the second position information to obtain accurate position information. Specifically, the first position information and the second position information are fused by the Kalman filtering algorithm to obtain the accurate position information of the spherical temperature and humidity sensor 2. The main control module 23 also controls the suction pump 24 through the PWM pulse width modulation signal, and controls the suction pump 24 based on the attitude information of the IMU module 27. At the same time, the main control module 23 also controls the working frequency of the temperature and humidity sensor module 21 based on the attitude information of the IMU module 27. The attitude information is used as the control input of the suction pump 24, and the suction speed of the suction pump 24 is controlled by the PWM pulse width modulation signal of the main control module 23. When the speed calculated by the IMU module 27 data is large, the suction rate of the suction pump 24 needs to be increased, and the measurement frequency of the temperature and humidity sensor module 21 and the position data fusion frequency also need to be increased to match the higher speed of the spherical sensor 2 rolling. Similarly, when the calculated motion speed of the spherical sensor 2 is small, the suction rate needs to be reduced to save power.

[0041] In the present application, when the spherical temperature and humidity sensor 2 rolls in a closed environment, the ball will contact the ground or the side wall in different postures, at which time the sensing part of the temperature and humidity sensor 21 cannot directly contact the air in the environment. By means of the air extraction function of the air extraction pump 24, external gas enters the interior through the air inlet of the spherical temperature and humidity sensor 2 to reach the measurement part of the temperature and humidity sensor 21, so as to improve the accuracy and rapidity of measurement.

[0042] In an embodiment, the temperature and humidity sensor 21 and the wireless communication module 22 share the same single-chip clock, and the temperature and humidity information and the positioning information are measured in one measurement period, and the temperature and humidity information and the positioning information in the same clock period are matched. By changing the clock frequency, the working frequency of the temperature and humidity sensor 21 and the wireless communication module 22 will be changed synchronously. When the reliable position information cannot be obtained, the measured temperature and humidity information cannot be correctly transmitted to the main control module 23 for storage, because the temperature and humidity data and the position data measured by the system are one-to-one corresponding.

[0043] In an embodiment, a key module 26 is further included, which is located at the top of the spherical temperature and humidity sensor 2, and is convenient for engineers to operate. The key module 26 starts the whole system and selects the system working mode through external keys. Specifically, the key module 26 is composed of a measurement key 261 and a transmission key 262. The working mode of the spherical temperature and humidity sensor 2 includes a measurement mode and a transmission mode, and the attitude information measured by the IMU module 27 switches the working mode during the working process of the spherical temperature and humidity sensor 2. The whole system is started by the measurement key, and the first position information, the second position information, the data fusion, and the temperature and humidity information are measured in turn. When the measurement process is completed and the IMU data is no longer updated, the spherical temperature and humidity sensor 2 is automatically switched to run in the transmission mode, and the wireless transmission of the measurement results is performed. Common wireless data transmission modes include Bluetooth, Zig-Bee, etc. Specifically, when the spherical sensor 2 runs in the transmission mode, the spherical sensor 2 will continuously send a connection request to the upper computer 3 in a cycle, and when the connection is successful, the spherical sensor 2 will transmit the saved temperature and humidity data and position data to the upper computer 3 through wireless transmission, and complete the operation of the whole system. The present application takes the attitude information as the switching sign of the system running mode. Specifically, when the spherical sensor 2 is in the measurement mode and no longer moves, the speed value calculated by the measurement is 0, and the second position information no longer changes. When ten sampling periods are cyclically waited, the speed value is still 0, and the second position information no longer changes, the spherical sensor 2 is automatically switched to run in the transmission mode.

[0044] In an embodiment, the air pump 24 is fixed above the main control module 23, and the air flow part of the air pump 24 is aligned with the detection part of the temperature and humidity sensing module 21. The temperature and humidity sensing module 21 is close to the surface of the spherical temperature and humidity sensor 2, and the surface of the spherical temperature and humidity sensor 2 has an air inlet near the close part of the temperature and humidity sensing module 21. The air pump 24 is used to assist the external air of the spherical temperature and humidity sensor 2 to enter the measurement part. According to the different data collected by the IMU module 27, the main control module 23 generates different PWM pulse width modulation signals to control the air pump 24 to work at different air pumping rates.

[0045] As shown in FIG. 1, the temperature and humidity sensing module 21 is fixed on the spherical temperature and humidity sensor 2, and the temperature and humidity sensing module 21 is fixed on the main control module 23. Figure 4 As shown in FIG. 2, it is a structural schematic diagram of the temperature and humidity sensing module in an embodiment. The temperature and humidity sensing module 21 includes a stacked thermocouple structure layer, a chamber structure layer, an electrolyte structure layer, a voltage control circuit 217 and a current detection circuit 216. The chamber structure layer includes a first chamber 211 and a second chamber 212. The thermocouple structure layer has a thermocouple loop 214 and a heating circuit 213 embedded in the thermocouple loop 214. The heating circuit 213 is adjacent to the first chamber 211 and the second chamber 212. The electrolyte structure layer includes an electrolyte 215, a top electrode arranged on the upper surface of the electrolyte 215, and a first bottom electrode exposed to the first chamber 211 and a second bottom electrode exposed to the second chamber 212 arranged on the lower surface of the electrolyte 215. The voltage control circuit 217 is used to apply voltage between the first bottom electrode and the top electrode, and between the second bottom electrode and the top electrode. The current detection circuit 216 is used to detect the current between the second bottom electrode and the top electrode. When the temperature and humidity sensing module 21 works, the heating circuit 213 heats each chamber of the temperature and humidity sensing module 21 to reach the working temperature. The oxygen in the original gas in the sensor is quickly consumed in the first chamber 211, and the remaining gas in the first chamber 211 diffuses to the second chamber 212, where water is decomposed to generate oxygen and hydrogen. According to the Nernst principle, the oxygen ions generated by the oxygen penetrate the zirconium oxide electrolyte to generate the Nernst current. The environmental humidity information is calculated from the current size of the second chamber 212. At the same time, the heating circuit 213 constitutes the free end of the thermocouple loop 214, and the outer wall of the thermocouple loop 214 is the working end in contact with the air. According to the thermoelectric electromotive force in the thermocouple loop 214, the environmental temperature information is calculated.

[0046] In an embodiment, the specific process of measuring humidity is as follows:

[0047] The main control module 23 controls the heating circuit 213 to heat to a working temperature of 780℃, and the main control module 23 controls the air pump 24 to pump the external air into the inside of the spherical temperature and humidity sensor 2.

[0048] The gas entering the inside of the spherical temperature and humidity sensor 2 is pumped into the first chamber 211 under the action of the voltage control circuit 217, and the consumption of oxygen in the original gas is completed in the first chamber 211. The specific method is to cause the following chemical reaction:

[0049] O2+4e - →2O 2-

[0050] Figure 4 The black part in the first chamber 211 is the bottom electrode. Oxygen ions are formed when oxygen contacts the bottom electrode of the first chamber 211. The oxygen ions penetrate the zirconia electrolyte under the control of the voltage control circuit 217 and are reduced to oxygen on the external electrode to be consumed and discharged.

[0051] After the reaction in the first chamber 211, the remaining water vapor and nitrogen in the measured gas, and the remaining gas diffuse to the second chamber 212 under the action of the voltage control circuit 217. In the second chamber 212, the following chemical reaction occurs:

[0052] 2H2O→2H2+O2

[0053] O2+4e - →2O 2-

[0054] The water vapor is decomposed into hydrogen and oxygen under the control of the voltage control circuit 217. The decomposed oxygen contacts the electrode to form oxygen ions, which penetrate the zirconia electrolyte and are reduced to oxygen on the external electrode.

[0055] It should be noted that the oxygen participating in the reaction in the second chamber 212 is all decomposed from water, so the size of the Nernst current at this time represents the concentration of water molecules in the air. The Nernst current intensity I N of the diffusion of oxygen ions from the inside of the chamber to the external electrode in the second chamber 212 is measured by the current detection circuit 216, and the environmental humidity information is calculated:

[0056] H2O% = F1(I N )

[0057] At the same time, due to the temperature difference between the heating circuit 213 and the outside, i.e. the temperature difference between the free end and the working end of the thermocouple circuit 214, a thermoelectric electromotive force V T is formed in the thermocouple circuit 214; since the temperature of the heating circuit 213 is relatively fixed, about 780°C, it serves as the free end of the thermocouple circuit 214, and the end directly contacting the outside serves as the working end of the thermocouple circuit 214. A thermoelectric electromotive force V T is formed, and the environmental temperature information is calculated:

[0058] T = F(V T )

[0059] So far, the temperature and humidity sensor module has completed the measurement of humidity H2O% and temperature T.

[0060] The common humidity sensor is composed of a humidity sensing element, which can be used at normal temperature. In special cases such as high temperature environment, the temperature will reach 200℃ and above, and the common humidity sensing element cannot complete accurate humidity measurement, because the capacitive humidity sensor is made of electrodes on an insulating substrate by screen printing or vacuum plating process, and then a humidity sensing glue is coated on the electrodes to make a capacitive humidity sensing element. It is difficult to achieve full humidity range linearity in design and process. At the same time, the large change of temperature will affect the capacitance C of the capacitor, resulting in inaccurate measurement. The above temperature and humidity sensor is designed in this embodiment, which integrates temperature measurement and humidity measurement, and uses a heating circuit to heat the chamber so that the humidity sensor can work as a temperature sensor with a fixed temperature free end to realize temperature measurement. Through simple design, multiple functions can be realized and applied to humidity measurement in high temperature environment.

[0061] In an embodiment, four base stations 1 are set up in a closed environment, the positions of each base station 1 are recorded and different ID numbers are assigned to the four base stations 1, and the spherical temperature and humidity sensor 2 is started through the button module 26. The base station 1 and the spherical temperature and humidity sensor 2 are measured by the two-way time of flight (TW-TOF) method, and the ranging process is as shown in Figure 5

[0062] Firstly, the spherical temperature and humidity sensor 2 sends a request signal P at time t1 and records the time stamp t1, and is received by the base station 1 at time t2, recording the receiving time stamp t2; then waits for time Y2, the base station 1 returns the R signal to the spherical temperature and humidity sensor 2 at time t3, records the time stamp t3, and the spherical temperature and humidity sensor 2 receives the R signal at time t4, records the time stamp t4;

[0063] It should be noted that the R signal contains the distance information d ab , t-1 of the last cycle.

[0064] After that, after time Y1, the spherical temperature and humidity sensor 2 sends the F signal to the base station 1 at time stamp t5, and the base station 1 receives the F signal at time t6, recording the time stamp t6.

[0065] It should be noted that the F signal sent by the spherical temperature and humidity sensor 2 contains the three time stamps t1, t4, t5 of the spherical temperature and humidity sensor 2 in this measurement process. Finally, the base station 1 calculates the distance between the spherical temperature and humidity sensor 2 and the base station 1 by the following algorithm, and the distance d​ab , t The R signal is sent to the spherical temperature and humidity sensor 2:

[0066] X1=t4-t1

[0067] Y1=t5-t4

[0068] X2=t6-t3

[0069] Y2=t3-t2

[0070]

[0071]

[0072] Wherein, c is the speed of light, the value is 299,792,458 meters per second, t i (I=123456) is the time stamp recorded during the measurement. By the above method, the distance information d ab between the base station 1 and the spherical temperature and humidity sensor 2 can be obtained, and one ranging period is completed. In a measurement period, four distance information d1, d2, d3, d4 are needed to complete four times of ranging.

[0073] Specifically, as Figure 6 shown, the UWB positioning algorithm is a TOA (Time of Arrival) algorithm, S1, S2, S3, S4 respectively correspond to the coordinates of the four base stations 1, and the coordinates of S1 are taken as the coordinate origin S1(x1, y1, z1). The coordinates of the spherical temperature and humidity sensor 2 are unknown coordinates X1(x, y, z).

[0074] The coordinates of the spherical temperature and humidity sensor are solved by the following equation group:

[0075]

[0076] Through the above equation, the first position information X1 of the spherical temperature and humidity sensor 2 at any time can be solved.

[0077] At the same time of UWB positioning, the IMU module 27 measures the three-axis acceleration and three-axis angular velocity of the spherical temperature and humidity sensor 2:

[0078] IMU=[a x ,a y ,a z ,w x ,w y ,w z ] T

[0079] The initial position is recorded as P0, and it is assumed that the position Xt and speed V t Calculate the second position information X2 according to the following formula;

[0080] First, based on the measured acceleration and angular velocity information, the average angular velocity and average acceleration at time t and time t+1 are used as the angular velocity and acceleration for the time interval from t to t+1:

[0081]

[0082]

[0083] Therefore, the velocity and position information at time t+1 can be calculated:

[0084] V t+1 =V t +a′ t Δt

[0085]

[0086] By calculating the position information in three coordinate directions, the second position information X2 of the spherical temperature and humidity sensor 2 is obtained, and V is saved. t+1 and X t+1 This prepares for calculating the velocity and position at the next moment.

[0087] The first position information X1 and the second position information X2 of the spherical temperature and humidity sensor 2 are measured through the above process. The two position information are then fused using a Kalman filter algorithm to obtain the accurate position information.

[0088] Specifically, such as Figure 7 As shown, the measurement mode of the spherical temperature and humidity sensor 2 is activated, and the spherical temperature and humidity sensor 2 is rolled into a high-temperature sealed environment. The temperature and humidity sensing module 21 completes the acquisition of temperature and humidity data, and the main control module 23 completes the fusion of position data. The acquired temperature and humidity data and the fused position data are stored in the main control module 23. It is determined whether the IMU attitude has been updated. If it has been updated, the collection of positioning information and temperature and humidity information continues. If it has not been updated, when the spherical temperature and humidity sensor 2 is switched to the transmission mode, the stored temperature and position information and temperature and humidity information are transmitted to the host computer 3 to obtain the temperature and humidity at different locations in the high-temperature sealed environment.

[0089] Those skilled in the art will readily understand that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A spherical temperature and humidity sensor, characterized by, The application relates to a sensor for measuring the temperature and humidity at different positions inside a closed environment, which comprises a spherical shell and a temperature and humidity sensing module, an IMU module, a wireless communication module, an air suction pump, a power module and a main control module wrapped in the spherical shell. The wireless communication module is used for wireless communication with a positioning base station in the closed environment so that the main control module obtains first position information of the sensor. The IMU module is used for collecting attitude information of the sensor so that the main control module obtains rolling speed variation of the sensor and second position information of the sensor. The air suction pump is used for sucking external air into the spherical shell, and the air suction rate changes with the rolling speed variation of the sensor, that is, when the rolling speed becomes faster, the air suction rate becomes faster, and when the rolling speed becomes slower, the air suction rate becomes slower. The temperature and humidity sensing module is used for measuring temperature and humidity information of the air sucked into the spherical shell by the air suction pump and storing the information in the main control module, and the working frequency of the temperature and humidity sensing module changes with the rolling speed variation of the sensor, that is, when the rolling speed becomes faster, the working frequency becomes faster, and when the rolling speed becomes slower, the working frequency becomes slower. The main control module is used for obtaining accurate positioning information by fusing the first position information and the second position information, and is used for transmitting the accurate positioning information and the temperature and humidity information to an external host computer through the wireless communication module when the sensor rolls into an open environment.

2. The spherical temperature and humidity sensor of claim 1, wherein, The sensor further comprises a key module, the key module comprises a measurement key and a transmission key, when the measurement key is started, the sensor is in a working mode of measuring positioning information and temperature and humidity information inside the closed environment, when the transmission key is started, the sensor is in a working mode of sending the stored positioning information and temperature and humidity information inside the closed environment to the host computer, when the IMU module detects that the sensor no longer rolls, the measurement key is automatically turned off and the transmission key is started.

3. The spherical temperature and humidity sensor of claim 1, wherein, The temperature and humidity sensing module comprises a stacked thermocouple structure layer, a chamber structure layer, an electrolyte structure layer, a voltage control circuit and a current detection circuit. The chamber structure layer is provided with a first chamber and a second chamber, the thermocouple structure layer has a heating circuit adjacent to the first chamber and the second chamber, the electrolyte structure layer comprises an electrolyte, a top electrode arranged on the upper surface of the electrolyte and a first bottom electrode exposed to the first chamber and a second bottom electrode exposed to the second chamber arranged on the lower surface of the electrolyte, the voltage control circuit is used for applying voltage between the first bottom electrode and the top electrode and between the second bottom electrode and the top electrode, and the current detection circuit is used for detecting the current between the second bottom electrode and the top electrode. When the temperature and humidity sensing module works: the heating circuit is heated to a fixed temperature as the free end of the thermocouple, and the structure other than the heating circuit is used as the working end to detect the temperature of the air inside the spherical shell and store it in the main control module; the air inside the spherical shell is first drawn into the first chamber by the air pump, and then enters the second chamber after the oxygen in the air is decomposed and consumed by the voltage control circuit, and then the water vapor in the air is decomposed and consumed by the voltage control circuit in the second chamber to form an electric current which is measured by the current detection circuit and fed back to the main control module, and the main control module calculates the humidity of the air inside the spherical shell according to the detected current.

4. The spherical temperature and humidity sensor of claim 3, wherein, The electrolyte is a zirconium oxide electrolyte.

5. The spherical temperature and humidity sensor of claim 1, wherein, The main control module is circular and matches the inner diameter of the spherical shell, and is placed at the inner diameter position of the spherical shell, the power module is placed on one side of the main control module, and the temperature and humidity sensing module, the IMU module, the wireless communication module and the air pump are placed on the other side of the main control module and placed on the main control module.

6. The spherical temperature and humidity sensor of claim 1, wherein, The positioning base station in the sealed environment is a UWB base station, and the wireless communication module is used to transmit UWB signals between the UWB base station to calculate the first position information of the sensor.

7. The spherical temperature and humidity sensor of claim 1, wherein, The spherical shell is made of high-temperature resistant silica gel.

8. The spherical temperature and humidity sensor of claim 1, wherein, The spherical temperature and humidity sensor is used to measure the temperature and humidity when the temperature is greater than or equal to 150℃ and less than or equal to 300℃.

9. A closed environment temperature and humidity measurement system, characterized by, The spherical temperature and humidity sensor is used to measure the temperature and humidity when the temperature is greater than or equal to 150℃ and less than or equal to 300℃.

10. A method of measuring temperature and humidity in a closed environment, characterized by, The spherical temperature and humidity sensor is used to measure the temperature and humidity when the temperature is greater than or equal to 150℃ and less than or equal to 300℃. The spherical temperature and humidity sensor is used to measure the temperature and humidity when the temperature is greater than or equal to 150℃ and less than or equal to 300℃.

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