Eurotium cristatum culture room environment control device and method based on multiple sensors

Abstract

The invention discloses an eurotium cristatum culture room environment control device and method based on multiple sensors, and belongs to the technical field of eurotium cristatum culture equipment.The eurotium cristatum culture room environment control device specifically structurally comprises a heat preservation box, an oscillator, a temperature and humidity sensor, an oxygen concentration sensor, a CO2 sensor, an illumination intensity sensor, an environment heating and refrigerating device, an air pump, an LED light source and an ultraviolet lamp; the heat preservation box comprises an outer-layer heat preservation box and a transparent inner-layer buffer chamber arranged in the outer-layer heat preservation box, and air holes are formed in the top and the four sides of the inner-layer buffer chamber; an oscillator is mounted in the inner-layer buffer chamber, and a temperature and humidity sensor, an oxygen concentration sensor and the like are mounted in the inner-layer buffer chamber; the air pump is used for supplying oxygen; the LED light source and the ultraviolet lamp are installed on the top of the inner side of the outer-layer heat preservation box According to the method, all primary and secondary influence factors in the eurotium cristatum culture environment are fully considered, and parameters in closed-loop feedback control can be automatically optimized. By using the device and the method disclosed by the invention, the fermentation efficiency of the eurotium cristatum is improved by more than 10% compared with the traditional fermentation.

Description

Technical Field

[0001] The present invention relates to the technical field of control equipment for a Eurotium cristatum culture chamber, and in particular to a multi-sensor-based environment control device for a Eurotium cristatum culture chamber, and also to a control method for the multi-sensor-based environment control device for a Eurotium cristatum culture chamber. Background Art

[0002] Eurotium cristatum, commonly known as "Golden Flower," is an important functional fungus in the family Eurotiumaceae, widely distributed in Fuzhuan brick tea, Cordyceps sinensis, and traditional Chinese medicine matrices. Recent studies have demonstrated that it possesses not only biological activities such as immune regulation and lipid-lowering properties, but also potential medical benefits such as anti-tumor and metabolic regulation. As a high-quality probiotic, it has attracted significant attention in the food and pharmaceutical sectors. These advantages have led to a growing demand for its use, necessitating the large-scale cultivation of Eurotium cristatum.

[0003] The traditional culture process of Aspergillus niger has poor effect in controlling environmental variables, which limits the growth efficiency of Aspergillus niger. Existing incubators generally have a single environmental parameter control, usually only temperature control, lack of multi-source information collection and multi-variable control mechanism and rapid feedback adjustment capabilities, and the culture time is relatively long. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a multi-sensor based environment control device and method for a culture chamber of Eurotium cristatum, which can achieve rich and accurate display of culture environment data of Eurotium cristatum, stable control of environmental variables and improvement of growth efficiency of Eurotium cristatum.

[0005] The solution adopted by the present invention is: a multi-sensor-based environment control device for a culture chamber of Eurotium cristatum, comprising:

[0006] An insulation box, comprising an outer insulation box and a transparent inner buffer chamber, wherein the outer insulation box is provided with a first accommodating cavity, the inner buffer chamber is fixedly connected within the first accommodating cavity, and the inner buffer chamber is provided with a second accommodating cavity, wherein the second accommodating cavity is provided with air holes on the top and four sides;

[0007] an oscillator, the oscillator being installed in the second accommodating cavity;

[0008] A temperature and humidity sensor installed in the inner buffer chamber;

[0009] An oxygen concentration sensor is installed in the inner buffer chamber;

[0010] A carbon dioxide sensor installed in the inner buffer chamber;

[0011] A light intensity sensor, the light intensity sensor being installed in the inner buffer chamber;

[0012] An environmental heating and cooling device, the environmental heating and cooling device being mounted on the top wall of the outer thermal insulation box for controlling the temperature of the first accommodating cavity;

[0013] an air pump, the air pump being connected to an air pipe, the air pipe being connected to the first accommodating cavity;

[0014] An LED light source, the LED light source being mounted on the top of the first accommodating cavity;

[0015] An ultraviolet lamp, the ultraviolet lamp being installed on the top of the first accommodating cavity;

[0016] A humidifier is installed on one side of the top of the first accommodating cavity.

[0017] Furthermore, the above-mentioned oxygen concentration sensor is connected to the main controller through a TTL to RS485 module, the temperature and humidity sensor, carbon dioxide sensor and light intensity sensor are connected to the main controller, the main controller is connected to a key module, a display module and a drive module, and the oscillator, environmental heating and cooling device, air pump, LED light source and ultraviolet lamp are connected to the drive module.

[0018] Furthermore, the above-mentioned environmental heating and cooling device includes a semiconductor refrigeration plate, a first fan and a second fan. The first fan and the second fan are installed at both ends of the semiconductor refrigeration plate. The semiconductor refrigeration plate is fixedly connected to the top wall of the outer insulation box through the shell. The semiconductor refrigeration plate achieves cooling and heating by changing the voltage direction.

[0019] Furthermore, a control circuit board and the air pump are installed on the outer side of the outer thermal insulation box, and the front side wall of the outer thermal insulation box has a door that can be opened sideways, and a transparent window is provided on the door.

[0020] A control method for a multi-sensor-based Eurotium cristatum culture room environment control device comprises the following steps:

[0021] (1) Environmentally friendly disinfection inside the culture room: Control the UVC-LED lamp to automatically stop working after 30 seconds to complete the disinfection of the culture room;

[0022] (2) Multi-source information collection: Temperature and humidity sensors, oxygen concentration sensors, carbon dioxide sensors, and light intensity sensors are arranged in the culture room to collect the environmental parameter information of temperature T, oxygen concentration O, light intensity L, humidity H, and carbon dioxide concentration C in the culture room in real time. The collected environmental parameter information is preliminarily filtered to remove noise interference and obtain the original data sequence X i(t), where i = 1, 2, 3..., n, n = 5 is the number of sensor types, t is the sampling time, the sampling period is 0.1 second, and the three main environmental parameters, temperature T, oxygen concentration O, and light intensity L, are selected for data fusion, and humidity H and carbon dioxide concentration C are displayed;

[0023] (3) Data preprocessing and recognition framework setting:

[0024] A. For the original data sequence X obtained in step (2) i (t) Perform historical data statistics, also known as evidence statistics method; the original data sequence X i (t) Divide the data into certain time windows ω, perform evidence statistics on the data in each time window, and obtain the basic probability assignment (BPA); in the experimental method, ω = 1 (ω is in seconds);

[0025] For temperature data T, calculate the probability distribution within the statistical time window;

[0026] For the oxygen concentration data O, calculate the probability distribution within the statistical time window;

[0027] For the light intensity data L, calculate the probability distribution within the statistical time window;

[0028] According to the growth characteristics of Eurotium cristatum

[0029] 1) Set the original data sequence temperature data T and its status:

[0030] X1(t)→(27℃≤X1(t)≤29℃) is: normal temperature value;

[0031] X1(t)→(29℃<X1(t)<40℃) means: the temperature is too high;

[0032] X1(t)→(0℃<X1(t)<27℃) means: low temperature;

[0033] The rest of X1(t) values ​​are: abnormal;

[0034] 2) Set the original data sequence oxygen concentration data O and its status:

[0035] X2(t)→(21%≤X2(t)≤25%) is: normal oxygen value;

[0036] X2(t)→(25%<X2(t)) means: oxygen value is too high;

[0037] X2(t)→(10%<X2(t)<21%) means: oxygen value is too low;

[0038] X2(t)→(X2(t)≤10%): abnormal;

[0039] 3) Set the original data sequence light intensity data L and its status:

[0040] X3(t)→(1.8lux≤X3(t)≤2.2lux) is: normal illumination value;

[0041] X3(t)→(2.2lux<X3(t)) means: the light intensity is too high;

[0042] X3(t)→(X3(t)<1.8lux) means: low light value;

[0043] X3(t)→(200lux<X3(t)): Abnormal;

[0044] The sensor sampling period is 0.1 seconds; there are m states (also called propositions), m = 10;

[0045] B. Identification framework:

[0046] Define the recognition framework θ, the number of recognition states (also called propositions) is m, then θ={θ1,θ2,……,θ m}, m = 10;

[0047] The historical data statistics method (also known as the evidence statistics method) is used to assign a basic probability assignment (BPA) to each element in the recognition frame θ. The following table shows an example of the basic probability assignment of the recognition frame θ obtained in a certain time window using the historical data statistics method.

[0048]

[0049] (4) Multi-source information fusion based on improved DS evidence theory:

[0050] The improved DS evidence theory is used for information fusion. The fusion steps are as follows:

[0051] First, suppose

[0052]

[0053] Where k represents the inconsistency factor of the evidence combination, k < 1, that is, the evidence conflict coefficient, m1(θ i ) is the state θ i The basic probability assignment, m2(θ j ) is the state θ j The basic probability assignment, m3(θ p ) is the state θ p The basic probability assignment is: i = 1, 2, ..., m; j = 1, 2, ..., m; p = 1, 2, ..., m; m = 10;

[0054] Secondly, due to the limitations of the synthesis rule, when faced with high-conflict data (i.e., when the inconsistency factor k of the evidence combination is too large), the basic probability assignment m1 (θ i )、m2(θ j )、m3(θ p ) is modified to improve the decision accuracy; the discount factor β is introduced, and the modified basic probability is assigned as: m1′(θ i )=βm1(θ i )、m2′(θ j )=βm2(θ j )、m3′(θ p )=βm3(θ p ); the discount factor β is adjusted according to the evidence conflict coefficient k. For example, when k is large (K>0.7), β takes a smaller value of 0.5; when 0.7≤k, β takes 1;

[0055] Finally, the modified basic probability assignments are fused using the DS synthesis rule to define the combined proposition θ jj The basic probability assignment is:

[0056]

[0057] Where m1′(θ i )、m2′(θ j )、m3′(θ p ) is the modified basic probability assignment; k is the inconsistency factor of the evidence combination, jj=1, 2, ..., m; i=1, 2, ..., m; j=1, 2, ..., m; p=1, 2, ..., m; m=10;

[0058] (5) Environmental status judgment and control decision-making:

[0059] A. Environmental state judgment: According to the basic probability assignment m(θ jj ), determine the current state of the culture room environment, and select the state with the largest basic probability value as the current environment state, that is, if m(θ jj )=max{m(θ1), m(θ2),..., m(θ jj )}, then the current environment state is θ jj ;

[0060] B. Control Decision: Based on the determined environmental conditions, discrete PID control is used for the incubation room environment. This means that optimal PID control parameter instructions are issued for the closed-loop feedback control of the environmental heating and cooling devices, air pump, and LED light source. The discrete PID control parameters are controlled according to the following table:

[0061] Parameter Mapping Temperature T Oxygen concentration Light intensity L Normal temperature <![CDATA[K TP1 =5,K TI1 =25,K TD1 =15]]> <![CDATA[K OP1 =2,K OI1 =5,K OD1 =1.5]]> <![CDATA[K LP1 =0.05,K LI1 =0.25,K LD1 =0.01]]> High temperature <![CDATA[K TP1 =4,K TI1 =22,K TD1 =12]]> <![CDATA[K OP1 =2,K OI1 =5,K OD1 =1.5]]> <![CDATA[K LP1 =0.05,K LI1 =0.25,K LD1 =0.01]]> Low temperature <![CDATA[K TP1 =6,K TI1 =20,K TD1 =15]]> <![CDATA[K OP1 =2,K OI1 =5,K OD1 =1.5]]> <![CDATA[K LP1 =0.05,K LI1 =0.25,K LD1 =0.01]]> Normal oxygen <![CDATA[K TP1 =5,K TI1 =25,K TD1 =15]]> <![CDATA[K OP1 =2,K OI1 =5,K OD1 =1.5]]> <![CDATA[K LP1 =0.05,K LI1 =0.25,K LD1 =0.01]]> High oxygen <![CDATA[K TP1 =5,K TI1 =25,K TD1 =15]]> <![CDATA[K OP1 =1.5,K OI1 =4,K OD1 =1.5]]> <![CDATA[K LP1 =0.05,K LI1 =0.25,K LD1 =0.01]]> Low oxygen <![CDATA[K TP1 =5,K TI1 =25,K TD1 =15]]> <![CDATA[K OP1 =3,K OI1 =4,K OD1 =2]]> <![CDATA[K LP1 =0.05,K LI1 =0.25,K LD1 =0.01]]> Normal lighting <![CDATA[K TP1 =5,K TI1 =25,K TD1 =15]]> <![CDATA[K OP1 =2,K OI1 =5,K OD1 =1.5]]> <![CDATA[K LP1 =0.05,K LI1 =0.25,K LD1 =0.01]]> High light <![CDATA[K TP1 =5,K TI1 =25,K TD1 =15]]> <![CDATA[K OP1 =2,K OI1 =5,K OD1 =1.5]]> <![CDATA[K LP1 =0.04,K LI1 =0.24,K LD1 =0.01]]> Low light <![CDATA[K TP1 =5,K TI1 =25,K TD1 =15]]> <![CDATA[K OP1 =2,K OI1 =5,K OD1 =1.5]]> <![CDATA[K LP1 =0.06,K LI1 =0.25,K LD1 =0.01]]> abnormal u(k)=u(k-1); screen display: abnormal u(k)=u(k-1); screen display: abnormal u(k)=u(k-1); screen display: abnormal

[0062] Among them, K TP1 , K TI1 , K TD1 are the proportional coefficient, integral coefficient and differential coefficient of the discrete PID temperature closed-loop controller respectively; K OP1 , K OI1 , K OD1 are the proportional coefficient, integral coefficient and differential coefficient of the discrete PID oxygen concentration closed-loop controller respectively; K LP1 , K LI1 , K LD1 are the proportional coefficient, integral coefficient and differential coefficient of the discretized PID light intensity closed-loop controller respectively; u(k) is the output of the regulator at the kth sampling (PWM (pulse width modulation) duty cycle), and u(k-1) is the output of the regulator at the k-1th sampling.

[0063] Beneficial effects of the present invention: Compared with the prior art, the present invention fully considers the influence of various major and minor factors in the culture environment of the cosmids on the growth of the cosmids, and fuses the information of the temperature, oxygen concentration and light intensity sensors in the cosmids culture room environment control device based on multi-sensor through multi-source information fusion based on the improved DS evidence theory, which can effectively improve the accuracy and reliability of the temperature, oxygen concentration and light intensity state judgment, reduce the influence of single sensor error or failure on the system judgment, and timely discover the abnormal conditions of temperature, oxygen concentration and light intensity in the cosmids culture room, so as to provide a stable and suitable environment for the cultivation of the cosmids. At the same time, the control decision is guided by the fused state, and the optimal PID parameters are automatically selected (mapped) according to different environmental states, thereby improving the system response speed and control accuracy, and improving the cultivation efficiency and quality of the cosmids, which has good application prospects and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 This is a schematic diagram of the front cross-sectional structure of a multi-sensor-based environment control device for a culture chamber of Eurotium cristatum;

[0065] Figure 2 This is a front view schematic diagram of the multi-sensor-based environmental control device for the Eurotium cristatum culture room;

[0066] Figure 3 It is a right view structural schematic diagram of the multi-sensor based Eurotium cristatum culture room environmental control device;

[0067] Figure 4 This is a schematic diagram of the control structure of the multi-sensor-based Eurotium cristatum culture room environment control device;

[0068] Figure 5This is a key interruption flow chart of a multi-sensor-based Eurotium cristatum culture room environment control device;

[0069] Figure 6 To cultivate the comparison curve. DETAILED DESCRIPTION

[0070] Cultivation of Eurotium cristatum in the laboratory mainly involves inoculating it with modified Czapek medium (CZG) and placing it in a microbial incubator for cultivation. Through research and experimental summary, the following conditions are required for artificial cultivation of Eurotium cristatum:

[0071] 1. Nutrients: Eurotium cristatum requires nutrients such as carbohydrates, nitrogen sources, and minerals, among which carbohydrates are its main source of nutrients.

[0072] 2. pH value: Eurotium cristatum can grow in an acidic environment, but an alkaline environment is not conducive to its growth. The pH value range for its growth is between 5.0-7.0, with the most suitable pH value being 5.5.

[0073] 3. Temperature: Extremely high and low temperatures are not conducive to the growth of Eurotium cristatum. Low temperatures favor the production of sexual spores, while high temperatures favor the production of asexual spores. The growth temperature of Eurotium cristatum is between 20-30°C, with the most suitable growth temperature being 30°C.

[0074] 4. Humidity: The growth environment of Eurotium cristatum has high requirements for humidity, which generally needs to be controlled above 80%.

[0075] 5. Oxygen: Eurotium cristatum is an aerobic bacterium. When cultured in liquid culture medium, sufficient oxygen supply needs to be provided, otherwise its growth will be hindered or even die.

[0076] 6. Light: Eurotium cristatum is suitable for cultivation in a dim environment. It grows faster under 1-3 lux light, and 2 lux is its best growth condition.

[0077] 7. Cleanliness: The cristatum has high requirements for the cleanliness of the environment and needs to grow under sterile conditions.

[0078] According to the above needs, the multi-sensor-based environment control device for the Eurotium cristatum culture chamber in Example 1 is provided for the cultivation of Eurotium cristatum.

[0079] Example 1: Figures 1-6As shown, a multi-sensor-based environment control device for a culture chamber of Eurotium cristatum comprises an insulated box 1, an oscillator 2, a temperature and humidity sensor 3, an oxygen concentration sensor 4, a carbon dioxide sensor 5, a light intensity sensor 6, an environment heating and cooling device 7, an air pump 8, an LED light source 9, an ultraviolet lamp 10, and a humidifier 14. The ultraviolet lamp 10 adopts an ultraviolet lamp UVC-LED.

[0080] LED light source 9 for illumination, ultraviolet lamp 10 for disinfection;

[0081] Among them, the insulated box 1 includes an outer insulated box 101 and a transparent inner buffer chamber 102. The outer insulated box 101 is provided with a first accommodating cavity 103. The inner buffer chamber 102 is fixed in the first accommodating cavity 103. The inner buffer chamber 102 is provided with a second accommodating cavity 104. The top and four sides of the second accommodating cavity 104 are provided with air holes 105. The top of the outer insulated box 101 has an opening 1011, and the hole 1011 is used to install the environmental heating and cooling device 7; the oscillator 2 is installed in the second accommodating cavity 104, and the oscillator 2 is provided with an accommodating cavity 201 for placing the culture bottle 12. The upper end of the accommodating cavity 201 is open, and a criss-cross spring rope 202 is provided at the opening. The spring rope 202 can limit the culture bottle 12, and the humidifier 14 is installed on the inner side wall of the first accommodating cavity through a bracket (adhesive tape);

[0082] The temperature and humidity sensor 3, the oxygen concentration sensor 4, the carbon dioxide sensor 5 and the light intensity sensor 6 are installed in the inner buffer chamber 102; the environmental heating and cooling device 7 is installed on the top wall of the outer insulation box 101 for temperature control of the first receiving cavity 103; the air pump 8 is connected to the air pipe 13, and the air pipe 13 is connected to the first receiving cavity 102 for oxygen content control of the first receiving cavity and the second receiving cavity; the LED light source 9 and the ultraviolet lamp 10 are both installed on the top of the first receiving cavity 102, the LED light source 9 provides light for the cultivation of the cysticercus cristatus, and the ultraviolet lamp 10 provides disinfection for the cysticercus cristatus cultivation room;

[0083] like Figure 4 As shown, the oxygen concentration sensor is connected to the main controller through a TTL to RS485 module, the temperature and humidity sensor, carbon dioxide sensor and light intensity sensor are connected to the main controller, the main controller is connected to a key module, a display module and a drive module, and the environmental heating and cooling device, air pump, LED light source and ultraviolet lamp are connected to the drive module.

[0084] like Figure 1As shown, the environment heating and cooling device 7 includes a semiconductor cooling chip 701, a first fan 702 and a second fan 703. The semiconductor cooling chip 701 is between the first fan 702 and the second fan 703, and the first fan 702 is above the semiconductor cooling chip 701. The semiconductor cooling chip 701 can both cool and heat. Therefore, the PID algorithm output can be positive or negative. When the output is positive, the system is heated; when the output is negative, the system is cooled.

[0085] The control circuit board 11 and the air pump 8 are installed on the outer side of the outer thermal insulation box 101, and a transparent window 1012 is provided on the front side wall of the outer thermal insulation box 101 to facilitate users to observe the internal situation.

[0086] Example 2: A control method for a multi-sensor-based Eurotium cristatum culture chamber environment control device, the control method comprising the following steps:

[0087] (1) Environmentally friendly disinfection inside the culture room: Control the UVC-LED lamp to automatically stop working after 30 seconds to complete the disinfection of the culture room;

[0088] (2) Multi-source information collection: Temperature and humidity sensors, oxygen concentration sensors, carbon dioxide sensors, and light intensity sensors are arranged in the culture room to collect the environmental parameter information of temperature T, oxygen concentration O, light intensity L, humidity H, and carbon dioxide concentration C in the culture room in real time. The collected environmental parameter information is preliminarily filtered to remove noise interference and obtain the original data sequence X i (t), where i = 1, 2, 3..., n, n = 5 is the number of sensor types, t is the sampling time (in seconds), the sampling period is 0.1 seconds, and the three main environmental parameters of temperature T, oxygen concentration O, and light intensity L are selected for data fusion. The main control circuit converts the received information into a displayable format and sends it to the display screen for display, which is convenient for the experimenter to observe;

[0089] (3) Data preprocessing and recognition framework setting:

[0090] A. For the original data sequence X obtained in step (2) i (t) Perform historical data statistics, also known as evidence statistics method; the original data sequence X i (t) Divide the data into certain time windows ω, perform evidence statistics on the data in each time window, and obtain the basic probability assignment (BPA); in the experimental method, ω = 1 (ω is in seconds);

[0091] For temperature data T, calculate the probability distribution within the statistical time window;

[0092] For the oxygen concentration data O, calculate the probability distribution within the statistical time window;

[0093] For the light intensity data L, calculate the probability distribution within the statistical time window;

[0094] According to the growth characteristics of Eurotium cristatum

[0095] 1) Set the original data sequence temperature data T and its status:

[0096] X1(t)→(27℃≤X1(t)≤29℃) is: normal temperature value;

[0097] X1(t)→(29℃<X1(t)<40℃) means: the temperature is too high;

[0098] X1(t)→(0℃<X1(t)<27℃) means: low temperature;

[0099] The rest of X1(t) values ​​are: abnormal;

[0100] 2) Set the original data sequence oxygen concentration data O and its status:

[0101] X2(t)→(21%≤X2(t)≤25%) is: normal oxygen value;

[0102] X2(t)→(25%<X2(t)) means: oxygen value is too high;

[0103] X2(t)→(10%<X2(t)<21%) means: oxygen value is too low;

[0104] X2(t)→(X2(t)≤10%): abnormal;

[0105] 3) Set the original data sequence light intensity data L and its status:

[0106] X3(t)→(1.8lux≤X3(t)≤2.2lux) is: normal illumination value;

[0107] X3(t)→(2.2lux<X3(t)) means: the light intensity is too high;

[0108] X3(t)→(X3(t)<1.8lux) means: low light value;

[0109] X3(t)→(200lux<X3(t)): Abnormal;

[0110] The sensor sampling period is 0.1 seconds; there are m states (also called propositions), m = 10;

[0111] An example of calculating the probability distribution within a statistical time window: In the experimental method, within a time window of ω = 1 second, 10 temperature data X1(t) are collected. If 8 temperature data are within the range of (27°C ≤ X1(t)) ≤ 29°C), 1 temperature data is within (X1(t)) < 27°C), and 1 temperature data is within (X1(t)) > 40°C), abnormal data is detected. Then the basic probability of temperature T being "normal" is assigned to 0.8, that is, m1(normal temperature) = 0.8; the basic probability of temperature T being "low" is assigned to 0.1, that is, m1(low temperature) = 0.1; the basic probability of temperature T being "abnormal" is assigned to 0.1, that is, m1(abnormal) = 0.1.

[0112] B. Identification framework:

[0113] Define the recognition framework θ, the number of recognition states (also called propositions) is m, then θ={θ1,θ2,……,θ m}, m = 10;

[0114] The historical data statistics method (also known as the evidence statistics method) is used to assign a basic probability assignment (BPA) to each element in the recognition frame θ. The following table shows an example of the basic probability assignment of the recognition frame θ obtained in a certain time window using the historical data statistics method.

[0115] Table 1 Basic probability assignment of recognition frame θ obtained in a certain time window

[0116]

[0117]

[0118] (4) Multi-source information fusion based on improved DS evidence theory:

[0119] The improved DS evidence theory is used for information fusion. The fusion steps are as follows:

[0120] First, suppose

[0121]

[0122] Where k represents the inconsistency factor of the evidence combination, k < 1, that is, the evidence conflict coefficient, m1(θ i ) is the state θ i The basic probability assignment, m2(θ j ) is the state θ j The basic probability assignment, m3(θ p ) is the state θ p The basic probability assignment is: i = 1, 2, ..., m; j = 1, 2, ..., m; p = 1, 2, ..., m; m = 10;

[0123] Secondly, due to the limitations of the synthesis rule, when faced with high-conflict data (i.e., when the inconsistency factor k of the evidence combination is too large), the basic probability assignment m1 (θ i )、m2(θ j )、m3(θ p ) is corrected to improve the decision accuracy; therefore, the discount factor β is introduced, and the corrected basic probability is assigned as: m1′(θ i )=βm1(θ i )、m2′(θ j )=βm2(θ j )、m3′(θ p )=βm3(θ p ); the discount factor β is adjusted according to the evidence conflict coefficient k. For example, when k is large (K>0.7), β takes a smaller value of 0.5; when 0.7≤k, β takes 1;

[0124] Finally, the modified basic probability assignments are fused using the DS synthesis rule to define the combined proposition θ jj The basic probability assignment is:

[0125]

[0126] Where m1′(θ i )、m2′(θ j )、m3′(θ p ) is the modified basic probability assignment; k is the inconsistency factor of the evidence combination, jj=1, 2, ..., m; i=1, 2, ..., m; j=1, 2, ..., m; p=1, 2, ..., m; m=10;

[0127] (5) Environmental status judgment and control decision-making:

[0128] A. Environmental state judgment: According to the basic probability assignment m(θ jj ), determine the current state of the culture room environment, and select the state with the largest basic probability value as the current environment state, that is, if m(θ jj )=max{m(θ1), m(θ2),..., m(θ jj )}, then the current environment state is θ jj ;

[0129] B. Control Decision: Based on the determined environmental conditions, discrete PID control is used for the incubation room environment. This means issuing optimized PID control parameter instructions for the closed-loop feedback control of the heating and cooling devices, air pump, and LED light source. This allows for faster, more accurate, and more stable regulation of the incubation room environment. Discrete PID control parameters are controlled according to the following table:

[0130] Table 2 Discrete PID control parameter selection

[0131] Parameter Mapping Temperature T Oxygen concentration Light intensity L Normal temperature <![CDATA[K TP1 =5,K TI1 =25,K TD1 =15]]> <![CDATA[K OP1 =2,K OI1 =5,K OD1 =1.5]]> <![CDATA[K LP1 =0.05,K LI1 =0.25,K LD1 =0.01]]> High temperature <![CDATA[K TP1 =4,K TI1 =22,K TD1 =12]]> <![CDATA[K OP1 =2,K OI1 =5,K OD1 =1.5]]> <![CDATA[K LP1 =0.05,K LI1 =0.25,K LD1 =0.01]]> Low temperature <![CDATA[K TP1 =6,K TI1 =20,K TD1 =15]]> <![CDATA[K OP1 =2,K OI1 =5,K OD1 =1.5]]> <![CDATA[K LP1 =0.05,K LI1 =0.25,K LD1 =0.01]]> Normal oxygen <![CDATA[K TP1 =5,K TI1 =25,K TD1 =15]]> <![CDATA[K OP1 =2,K OI1 =5,K OD1 =1.5]]> <![CDATA[K LP1 =0.05,K LI1 =0.25,K LD1 =0.01]]> High oxygen <![CDATA[K TP1 =5,K TI1 =25,K TD1 =15]]> <![CDATA[K OP1 =1.5,K OI1 =4,K OD1 =1.5]]> <![CDATA[K LP1 =0.05,K LI1 =0.25,K LD1 =0.01]]> Low oxygen <![CDATA[K TP1 =5,K TI1 =25,K TD1 =15]]> <![CDATA[K OP1 =3,K OI1 =4,K OD1 =2]]> <![CDATA[K LP1 =0.05,K LI1 =0.25,K LD1 =0.01]]> Normal lighting <![CDATA[K TP1 =5,K TI1 =25,K TD1 =15]]> <![CDATA[K OP1 =2,K OI1 =5,K OD1 =1.5]]> <![CDATA[K LP1 =0.05,K LI1 =0.25,K LD1 =0.01]]> High light <![CDATA[K TP1 =5,K TI1 =25,K TD1 =15]]> <![CDATA[K OP1 =2,K OI1 =5,K OD1 =1.5]]> <![CDATA[K LP1 =0.04,K LI1 =0.24,K LD1 =0.01]]> Low light <![CDATA[K TP1 =5,K TI1 =25,K TD1 =15]]> <![CDATA[K OP1 =2,K OI1 =5,K OD1 =1.5]]> <![CDATA[K LP1 =0.06,K LI1 =0.25,K LD1 =0.01]]> abnormal u(k)=u(k-1); screen display: abnormal u(k)=u(k-1); screen display: abnormal u(k)=u(k-1); screen display: abnormal

[0132] Among them, K TP1 , K TI1 , K TD1 are the proportional coefficient, integral coefficient and differential coefficient of the discrete PID temperature closed-loop controller respectively; K OP1 , K OI1 , K OD1 are the proportional coefficient, integral coefficient and differential coefficient of the discrete PID oxygen concentration closed-loop controller respectively; K LP1 , K LI1 , K LD1 are the proportional coefficient, integral coefficient and differential coefficient of the discretized PID light intensity closed-loop controller respectively; u(k) is the output of the regulator at the kth sampling (PWM (pulse width modulation) duty cycle), and u(k-1) is the output of the regulator at the k-1th sampling.

[0133] By fusing information from the temperature, oxygen concentration, and light intensity sensors in a multi-sensor Eurotium cristatum cultivation chamber's environmental control device based on a modified DS evidence theory, the system effectively improves the accuracy and reliability of temperature, oxygen concentration, and light intensity state judgments. This reduces the impact of individual sensor errors or failures on system judgments, allowing for timely detection of abnormalities in temperature, oxygen concentration, and light intensity within the chamber, thereby providing a stable and suitable environment for the cultivation of the fungus. Furthermore, the fused state guides control decisions, automatically selecting (mapping) optimal PID parameters based on different environmental conditions, improving system response speed and control accuracy.

[0134] After multi-source information fusion, it can effectively provide a basis for control decision-making. Automatic control is to automatically control the corresponding actuators, that is, the closed-loop feedback control mechanism of the environmental state: discrete PID control with a limited value is used for temperature, oxygen concentration and light intensity, thereby achieving more accurate automatic control with smaller steady-state error. The discrete PID expression is:

[0135] u(k)=u(k-1)+K P [E(k)-E(k-1)]+K I E(k)+K D [E(k)-2E(k)+E(k-2)]

[0136] Where u(k) is the output of the regulator at the kth sampling (PWM (pulse width modulation) duty cycle), u(k-1) is the output of the regulator at the k-1th sampling, E(k) is the deviation value at the kth sampling, E(k-1) is the deviation value at the k-1th sampling, E(k-2) is the deviation value at the k-2th sampling, and K P is the proportionality coefficient, K I is the integral coefficient, K D is the differential coefficient; at the same time, in this invention, the data storage in the PID algorithm is also improved. In order to save system storage space, u(k-1) is not stored, but the previous PWM output value is obtained through the TIM_GetCapture2 (TIM2) function.

[0137] According to the model parameters of the device of the present invention, the parameters are set based on the empirical method and experiments. The initial temperature control parameter setting value is: K P =5,K I =25,K D =15; the setting value of oxygen concentration control parameter is: K P =2,K I =5,K D =1.5; the setting value of the light intensity control parameter is: K P =0.05,K I =0.25,K D =0.01.

[0138] In this control, the data storage in the PID algorithm is improved. To save system storage space, u(k-1) is not stored. Instead, the previous PWM output value is obtained through the TIM_GetCapture2(TIM2) function.

[0139] The subroutine code is as follows:

[0140] void EXECUTE_led(uint8_t UVC_flag,uint16_t lux,uint16_tset_lux,int16_t*PID_error)

[0141] {float K P =K LP1 ,K I =K LI1 ,K D =K LD1 ;

[0142] int16_t add = 0;

[0143] if(UVC_flag==0){

[0144] PID_error[0] = set_lux - lux;

[0145] add=(Kp*(PID_error[0]-PID_error[1])+Ki*PID_error[0]+Kd*(PID_error[0]-2*PID_error[1]+PID_error[2]));

[0146] PID_error[2]=PID_error[1], PID_error[1]=PID_error[0];

[0147] add=add+TIM_GetCapture2(TIM2);

[0148] if(add>=1000)

[0149] LED_PWM(1000);

[0150] else if (add<=0)

[0151] LED_PWM(0);

[0152] else

[0153] LED_PWM(add);

[0154] }

[0155] }

[0156] The experiment was conducted using the solution of the present invention. The outer insulation box was made of engineering plastic (PVC). The front end of the engineering plastic box was open, and the opening was covered with a front cover. The front cover was provided with a transparent window. The top of the transparent inner buffer chamber was a detachable cover for convenient placement of culture bottles. The parameters were automatically (or manually) set as shown above.

[0157] Experimental results and analysis: The optimal culture conditions for liquid fermentation of Eurotium cristatum are: initial pH 5.5, culture temperature 30℃, inoculation amount 1% (spore concentration 6*10 8 cfu / mL), and an oscillator at 120 rpm. The initial conditions of the conventional process and the apparatus and experimental method of the present invention were set to be the same. The conventional process used conventional light and other conventional controls, while the present invention set the culture environment to 2 lux and an oxygen concentration of 21%.

[0158] The experimental results show that in the traditional process, the mycelium reaches a peak value of 0.3754 g / 100 mL at 84 hours. Using the device and experimental method of the present invention, the mycelium reaches a peak value of 0.3783 g / 100 mL at 72 hours.

[0159] In microbial liquid fermentation, efficiency is typically measured as grams of metabolites per liter of fermentation liquid per hour. In this experiment, since the mycelium of Eurotium cristatum can be directly used in subsequent production after rinsing with sterile water, efficiency was expressed as dry weight of mycelium per 100 milliliters of fermentation liquid per hour to facilitate comparison with the original control.

[0160] Calculation formula:

[0161] η=M / (L·T)*100%

[0162] Wherein, M is the dry weight of mycelium corresponding to the end of the logarithmic phase, in g, L is a fixed value of 100 mL, and T is the end of the logarithmic phase, in h.

[0163] Therefore, the fermentation (production) efficiency of the original control is:

[0164] 0.3754 / 84=0.447%

[0165] The fermentation (production) efficiency using the equipment and method of the present invention is:

[0166] 0.3783 / 72=0.525%

[0167] The overall efficiency improvement is:

[0168] 0.525% / 0.447%=1.174, which means the fermentation process of the new system improves efficiency by 17.4% compared with the traditional method.

[0169] At the same time, the dry weight of mycelium in the traditional method at 72 hours is about 0.32g / mL, which is close to the end of the logarithmic phase. If the fermentation (production) efficiency is calculated at this period, it is:

[0170] 0.32 / 72=0.444%

[0171] During this time period, the overall improvement efficiency is:

[0172] 0.525% / 0.444%=1.182, which means that the fermentation process of the new system improves efficiency by 18.2% compared with the traditional method.

[0173] The results showed that the application of the environmental control device for the culture chamber of the Aspergillus niger and its experimental method increased the fermentation efficiency of the Aspergillus niger by more than 10% compared with traditional fermentation.

[0174] The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A multi-sensor-based environmental control device for a Eurotium cristatum culture room, characterized in that: include: An insulation box, comprising an outer insulation box and a transparent inner buffer chamber, wherein the outer insulation box is provided with a first accommodating cavity, the inner buffer chamber is fixedly connected within the first accommodating cavity, and the inner buffer chamber is provided with a second accommodating cavity, wherein the second accommodating cavity is provided with air holes on the top and four sides; an oscillator, the oscillator being installed in the second accommodating cavity; A temperature and humidity sensor installed in the inner buffer chamber; An oxygen concentration sensor is installed in the inner buffer chamber; A carbon dioxide sensor installed in the inner buffer chamber; A light intensity sensor, the light intensity sensor being installed in the inner buffer chamber; An environmental heating and cooling device, the environmental heating and cooling device being mounted on the top wall of the outer thermal insulation box for controlling the temperature of the first accommodating cavity; an air pump, the air pump being connected to an air pipe, the air pipe being connected to the first accommodating cavity; An LED light source, the LED light source being mounted on the top of the first accommodating cavity; an ultraviolet lamp, the ultraviolet lamp being mounted on the top of the first accommodating cavity; A humidifier is installed on one side of the top of the first accommodating cavity.

2. The multi-sensor-based environment control device for a Eurotium cristatum culture chamber according to claim 1, characterized in that: The oxygen concentration sensor is connected to the main controller through a TTL to RS485 module, the temperature and humidity sensor, the carbon dioxide sensor and the light intensity sensor are connected to the main controller, the main controller is connected to a key module, a display module and a drive module, and the oscillator, the environmental heating and cooling device, the air pump, the LED light source and the ultraviolet lamp are connected to the drive module.

3. The multi-sensor-based environment control device for a Eurotium cristatum culture chamber according to claim 1, characterized in that: The environmental heating and cooling device includes a semiconductor refrigeration plate, a first fan and a second fan. The first fan and the second fan are installed at both ends of the semiconductor refrigeration plate. The semiconductor refrigeration plate is fixedly connected to the top wall of the outer insulation box through a shell. The semiconductor refrigeration plate achieves cooling and heating by changing the voltage direction.

4. The multi-sensor-based environment control device for a Eurotium cristatum culture chamber according to claim 1, characterized in that: The control circuit board and the air pump are installed on the outer side of the outer thermal insulation box. The front side wall of the outer thermal insulation box is provided with a box door which can be opened sideways, and a transparent window is arranged on the box door.

5. The control method of the multi-sensor-based Eurotium cristatum culture room environment control device according to claim 1, characterized in that: The control method comprises the following steps: (1) Environmentally friendly disinfection inside the culture room: the UV lamp is controlled to automatically stop working after 30 seconds to complete the disinfection of the culture room; (2) Multi-source information collection: Temperature and humidity sensors, oxygen concentration sensors, carbon dioxide sensors, and light intensity sensors are arranged in the culture room to collect the environmental parameter information of temperature T, oxygen concentration O, light intensity L, humidity H, and carbon dioxide concentration C in the culture room in real time. The collected environmental parameter information is preliminarily filtered to remove noise interference and obtain the original data sequence X i (t), where i = 1, 2, 3..., n, n = 5 is the number of sensor types, t is the sampling time, the sampling period is 0.1 second, and the three main environmental parameters, temperature T, oxygen concentration O, and light intensity L, are selected for data fusion, and humidity H and carbon dioxide concentration C are displayed; (3) Data preprocessing and recognition framework setting: A. For the original data sequence X obtained in step (2) i (t) Perform historical data statistics; convert the original data sequence X i (t) Divide the data into certain time windows ω, perform evidence statistics on the data in each time window, and obtain basic probability assignment; in the experimental method, ω = 1; For temperature data T, calculate the probability distribution within the statistical time window; For the oxygen concentration data O, calculate the probability distribution within the statistical time window; For the light intensity data L, calculate the probability distribution within the statistical time window; According to the growth characteristics of Eurotium cristatum 1) Set the original data sequence temperature data T and its status: X1(t)→(27℃≤X1(t)≤29℃) is: normal temperature value; X1(t)→(29℃<X1(t)<40℃) means: the temperature is too high; X1(t)→(0℃<X1(t)<27℃) means: low temperature; The rest of X1(t) values ​​are: abnormal; 2) Set the original data sequence oxygen concentration data O and its status: X2(t)→(21%≤X2(t)≤25%) is: normal oxygen value; X2(t)→(25%<X2(t)) means: oxygen value is too high; X2(t)→(10%<X2(t)<21%) means: oxygen value is too low; X2(t)→(X2(t)≤10%): abnormal; 3) Set the original data sequence light intensity data L and its status: X3(t)→(1.8lux≤X3(t)≤2.2lux) is: normal illumination value; X3(t)→(2.2lux<X3(t)) means: the light intensity is too high; X3(t)→(X3(t)<1.8lux) means: low light value; X3(t)→(200lux<X3(t)): Abnormal; The sensor sampling period is 0.1 seconds; there are m states in total, m = 10; B. Identification framework: Define the recognition framework θ, the number of recognition states (also called propositions) is m, then θ={θ1,θ2,……,θ m }, m = 10; Use historical data statistics to assign basic probability values ​​to each element in the recognition framework θ; (4) Multi-source information fusion based on improved DS evidence theory: The improved DS evidence theory is used for information fusion. The fusion steps are as follows: First, suppose Where k represents the inconsistency factor of the evidence combination, k < 1, that is, the evidence conflict coefficient, m1(θ i ) is the state θ i The basic probability assignment, m2(θ j ) is the state θ j The basic probability assignment, m3(θ p ) is the state θ p The basic probability assignment is: i = 1, 2, ..., m; j = 1, 2, ..., m; p = 1, 2, ..., m; m = 10; Secondly, assign the basic probability m1(θ i )、m2(θ j )、m3(θ p ) is modified and a discount factor β is introduced. The modified basic probability is assigned as: m1′(θ i )=βm1(θ i )、m2′(θ j )=βm2(θ j )、m3′(θ p )=βm3(θ p ); the discount factor β is adjusted according to the evidence conflict coefficient k. For example, when k is large (K>0.7), β takes a smaller value of 0.5; when 0.7≤k, β takes 1; Finally, the modified basic probability assignments are fused using the DS synthesis rule to define the combined proposition θ jj The basic probability assignment is: Where m1′(θ i )、m2′(θ j )、m3′(θ p ) is the modified basic probability assignment; k is the inconsistency factor of the evidence combination, jj=1, 2, ..., m; i=1, 2, ..., m; j=1, 2, ..., m; p=1, 2, ..., m; m=10; (5) Environmental status judgment and control decision-making: A. Environmental state judgment: According to the basic probability assignment m(θ jj ), determine the current state of the culture room environment, and select the state with the largest basic probability value as the current environment state, that is, if m(θ jj )=max{m(θ1), m(θ2),..., m(θ jj )}, then the current environment state is θ jj ; B. Control Decision: Based on the determined environmental conditions, discrete PID control is used for the incubation room environment. This means that optimal PID control parameter instructions are issued for the closed-loop feedback control of the environmental heating and cooling devices, air pump, and LED light source. The discrete PID control parameters are controlled according to the following table: Among them, K TP1 , K TI1 and K TD1 are the proportional coefficient, integral coefficient and differential coefficient of the discrete PID temperature closed-loop controller respectively; K OP1 , K OI1 and K OD1 are the proportional coefficient, integral coefficient and differential coefficient of the discrete PID oxygen concentration closed-loop controller respectively; K LP1 , K LI1 and K LD1 are the proportional coefficient, integral coefficient and differential coefficient of the discretized PID light intensity closed-loop controller respectively; u(k) is the output of the regulator at the kth sampling time, and u(k-1) is the output of the regulator at the k-1th sampling time.

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