A method and device for real-time display of hob heat maps

Abstract

The present invention provides a method and device for real-time display of hob heat maps. The steps of the method are as follows: determine the installation position of the hob on the cutter head according to the cutter head diagram; use a temperature sensor to measure the temperature value of the hob in real time; establish a cutter head temperature image, and mark the measured temperature value of the hob in the cutter head temperature image according to the installation position of the hob on the cutter head; deduce the adjacent temperature values of the hob according to the interpolation algorithm to obtain the temperature values of all pixel points in the cutter head temperature image; combine the temperature-to-color value algorithm to convert the temperature value into a color value to obtain the hob heat map; according to the obtained color value, refresh the pixel points of the hob heat map in sequence to achieve real-time display of the heat. The present invention introduces a heat map in the field of tunnel construction, can refresh the hob heat map in real time, can intuitively and quickly obtain the temperature information of all the cutters on the cutter head, and then analyze and judge the states of each cutter, greatly improving the work efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel construction, and in particular to a method and device for real-time display of a hob thermal map, realizing the real-time display of the temperature thermal map of a shield hob. Background Art

[0002] The temperature information of the cutter is closely related to the cutter state. When faults such as mud caking, jamming rotation, and eccentric wear occur to the cutter, the cutter temperature will change significantly. At present, the cutter information monitoring system of a shield machine can only obtain various temperature information of the cutters one by one in the form of a cutter information list. However, since there are a large number of cutters on the shield machine, obtaining the cutter temperature one by one in the form of a cutter information list cannot quickly and intuitively obtain the current cutter temperature information, and cannot overall control the cutter temperature. It is even more difficult to judge the state of each cutter through the temperature information of the cutters on the entire cutter head. Once faults such as mud caking and jamming rotation occur to the cutter and are not discovered in time, it will lead to a low tunneling efficiency of the shield machine. At the same time, it will seriously damage the cutters and reduce the service life of the cutter head.

[0003] In recent years, with the development of technology, relevant research on heat maps has gradually emerged. Heat maps have the advantages of quickly and intuitively reflecting various parameters, depicting the overall appearance of data, and facilitating comparison between data sets, so they are widely used in various industries. For example, the patent application number is 201810317433.8, and the invention name is a method and system for generating a heat map. This method is used in the retail technology field to determine the number of people flow based on image recognition, and then establish a model with the statistics of the counter real-scene image to generate a heat map module, so as to provide decision-making data for operators in each retail area. However, during the actual tunneling process of a shield machine, the surface of the cutter is often wrapped with mud or muck, and the temperature of the cutter head of the shield machine cannot be accurately calculated by the method of image recognition. The patent application number is 201810713107.9, and the invention name is a method and system for real-time display of a heat map. This method is used in the computer field to establish a model based on the statistics of website traffic to generate a heat map display module. By analyzing the access behavior of users on the website, the preferences and interest distributions of users can be obtained, so as to provide a basis for website optimization to maximize the value of the website. However, during the actual tunneling process of a shield machine, the cutter head is fixedly installed on the cutter disc and rotates with the rotation of the cutter disc, and the access volume of the cutter head cannot be counted. Both of the above two patents have the disadvantages of complex model establishment and difficulty in obtaining real-time data. The publication number is CN 114382542 A, and the invention name is a method for detecting cutter disc mud cake formation. Kriging algorithm and convolution method are used for interpolation operation. Although the data accuracy problem is solved, the calculation steps are cumbersome and the interpolation speed is extremely slow. It takes 1 minute to complete one update, which is completely inconsistent with the requirement of real-time update in engineering. Therefore, it is very necessary to design a heat map detection method and device with strong practicability, high accuracy and capable of intuitively and real-time displaying the temperature of the cutter head in the tunnel construction technology field. Summary of the Invention

[0004] Aiming at the technical problem that the existing heat map display technology cannot comprehensively control the temperature of the cutter and judge the cutter state, the present invention proposes a heat map detection method and device with strong practicability, high accuracy and capable of intuitively and real-time displaying the temperature of the cutter head. By introducing the heat map into the tunnel construction field, the real-time display of the heat map of the cutter head temperature can be realized, the temperature of the cutter can be comprehensively controlled through the heat map, the cutter state can be judged, and the calculation is simple.

[0005] In order to achieve the above object, the technical solution of the present invention is realized as follows: A method for real-time display of the heat map of the cutter head, the steps are as follows:

[0006] Step 1: Determine the installation position of the cutter head on the cutter disc according to the cutter disc diagram;

[0007] Step 2: Use a temperature sensor to measure the temperature value of the cutter head in real time;

[0008] Step 3: Establish a cutter head temperature image, and mark the measured temperature values of the hob on the cutter head temperature image according to the installation positions of the hobs on the cutter head;

[0009] Step 4: Derive the adjacent temperature values of the hob according to the interpolation algorithm to obtain the temperature values of all pixel points in the cutter head temperature image;

[0010] Step 5: Combine the actual project and confirm the temperature-to-color value algorithm based on a large number of tests, and convert the temperature values obtained in Step 4 into color values to obtain a hob heat map;

[0011] Step 6: Refresh the pixel points of the hob heat map in sequence according to the obtained color values, so as to realize the real-time display of the heat.

[0012] Preferably, install a temperature sensor on each hob of the cutter head. The real-time temperature values of the hobs measured by the temperature sensors are T1, T2,.., Tn,.., TN respectively; Tn is the temperature value of the nth hob, n = 1 - N, and N is the total number of hobs on the cutter head; the cutter head temperature image is a circle with a pixel P as the diameter.

[0013] Preferably, the cutter head diagram provides the installation radius Z of the hob and the installation angle θ of the hob. Determine the installation position of the hob according to the cutter head radius and the installation angle of the hob; establish a plane coordinate system with the center point of the cutter head as the origin; through the installation position of the hob and the cutter head diameter D and pixel P, convert the installation position of the hob into a coordinate point on the plane coordinate system:

[0014] (R1*Z*Cosθ, R1*Z*Sinθ), the ratio R1 = P / D; then the coordinate points of the hob on the cutter head temperature image are: hob 1 is (x1, y1), hob 2 is (x2, y2).. hob n is (x n , y n ).. hob N is (x N , y N ).

[0015] Preferably, the method for deriving the adjacent temperature values of the hob according to the difference algorithm in Step 4 is: divide the circle of the cutter head temperature image into M blocks of data points, the pixels of each block of data points are 1*1, and mark the values of the coordinate points of the installation position of the hob or the coordinate points in its neighborhood as the measured temperature values of the hob; use the cubic spline interpolation method to interpolate the data points between N hobs, and use the inverse distance weighting method to interpolate the remaining data points.

[0016] Preferably, the implementation method of interpolating the data points between N hobs by the cubic spline interpolation method is:

[0017] 4.1 Starting from hob 1, calculate the distances d1, d2,... dz between hob 1 and hobs 2, 3,... N, where z = N - 1; obtain the hob closest to hob 1 as hob s through the distances d1, d2,... dz, 2 <= s <= N;

[0018] 4.2 Perform interpolation between hob 1 and hob s. If there are S + 1 data points between hob 1 and hob s, there will be S intervals, which divides the curve into S segments; establish a cubic spline curve equation and solve it sequentially to obtain the temperature values of each interpolation for each data point;

[0019] 4.3 Sequentially loop through steps 4.1 - 4.2 to obtain the interpolations between two points of hobs 2, 3,... n; and only one interpolation calculation is allowed for the two closest hobs.

[0020] Preferably, the method for establishing the cubic spline curve equation and solving to obtain each interpolation is as follows:

[0021] Let each curve segment be S(x), and let the x coordinates of the data points x0, x1, x2,..x S be arranged in ascending order, and the values corresponding to each point be y0, y1, y2,..y S ; determine the conditions for each curve segment S(x) to satisfy the following three curve equation characteristics based on the hob installation positions determined from the cutter head diagram:

[0022] a. In each sub - interval [x i , x i+1 , i = 0, 1,…, S - 1, the curve S(x) = S i (x) is a cubic polynomial;

[0023] b. Satisfy S(x i ) = y i ;

[0024] c. The curve S(x), its derivative S'(x), and second - derivative S″(x) are continuous in the interval [x0, x s , that is, the curve S(x) is smooth;

[0025] Then the curve S(x) is expressed as: S i (x) = a i +b i (x - x i )+c i (x - x i ) 2 +d i (x - x i ) 3 ; where, a i 、b i, c i , d i are the cubic spline interpolation coefficients of the curve equation between adjacent hob cutters respectively;

[0026] According to the conditions a and b of the curve equation characteristics and the continuity of the curve S i (x), we can get:

[0027] S i (x i ) = y i

[0028] S i (x i+1 ) = y i+1 ;

[0029] S i '(x i+1 ) = S i ' +1 (x i+1 )

[0030] S″ i (x i+1 ) = S″ i+1 (x i+1 );

[0031] According to condition c and combined with the first derivative and second derivative of the curve S(x), we can get:

[0032] S i (x) = a i + b i (x - x i ) + c i (x - x i ) 2 + d i (x - x i ) 3

[0033] S i '(x) = b i + 2c i (x - x i ) + 3d i (x - x i ) 2

[0034] S″ i (x) = 2c i + 6d i (x - x i );

[0035] Let h i = x i+1 - x iDenoting the i-th segment interval, it is deduced that: a i = y i ,

[0036] Then it is deduced that:

[0037]

[0038] S i ' +1 (x i+1 ) = b i+1 + 2c i+1 (x i+1 - x i+1 ) + 3d i+1 (x i+1 - x i+1 ) 2 = b i+1 ;

[0039]

[0040] Let S″ i (x i ) = m i Then it is obtained that:

[0041] It can be deduced that:

[0042] It can be obtained that

[0043] Since the temperature values between the first and last hob of the simulated cubic curve are known, that is, interpolation calculation is not required at both ends of the curve, it can be expressed as:

[0044] The system of equations to be solved can be obtained as:

[0045]

[0046] Among them, n = S;

[0047] The values of m0, m1, m2,..., mS are obtained through matrix operations, and then the cubic spline interpolation coefficients a i , b i , c i , d i are obtained, and the cubic curve equation is obtained. By solving sequentially, the respective interpolation temperatures are obtained.

[0048] Preferably, the implementation method of the inverse proportional weight method is: the final temperature value of point p1 is jointly determined by the temperature values of N known hobs on the plane, and

[0049]

[0050] Among them, T n represents the temperature value of hob n, and d n represents the distance between the coordinate point of hob n and the p1-th point when deriving the temperature at point p1, where 0 < n <= N; p1 is any one of the remaining data points.

[0051] Preferably, the implementation method of the temperature-to-color value algorithm in step 5 is as follows:

[0052] 1) The color level change is set to color levels C1, C2, and C3. The color levels C1, C2, and C3 are respectively between red, yellow, and green in the hob heat map;

[0053] 2) Set the maximum value of the temperature value of the hob to Tmax and the minimum value to Tmin; calculate the temperature conversion factor Tp = Tn / (Tmax - Tmin);

[0054] 3) Calculate the color value of each pixel point according to the adjacent color level change algorithm using the temperature conversion factor.

[0055] Preferably, the implementation method of the adjacent color level change algorithm is as follows:

[0056] Any color display is composed of R, G, and B, and the ranges of R, G, and B are between [0, 255];

[0057] Taking color levels C u and C u+1 as an example, the conversion steps are as follows:

[0058] [[ID=¾]]Calculate the numerical values of the color values R, G, and B respectively as:

[0059] R = C u .R * (1.0 - T p ) + C u+1 .R * T p

[0060] G = C u .G * (1.0 - T p ) + C u+1 .G * T p

[0061] B = C u .B * (1.0 - T p ) + C u+1 .B * T p

[0062] Among them, C u .R and C u+1 .R respectively represent the color levels C uand C u+1 the red component in C u .G and C u+1 .G respectively represent the color level C u and C u+1 the green component in C u .B and C u+1 .B respectively represent the color level C u and C u+1 the blue component in;

[0063] According to the color values R, G, B, the display color value of the pixel is calculated by using the color value change function Color.FromRgb(R, G, B).

[0064] When there are multiple levels of color display, the color values R, G, B between each color level are calculated recursively in turn, and the number of recursive times is 3 times.

[0065] An apparatus for real-time display of a hob thermal map, including a data acquisition unit and an industrial control computer. The data acquisition unit is connected to the industrial control computer. The industrial control computer is provided with a data storage module, a data processing module and a data display module. The data storage module stores the temperature values of N hobs collected by the data acquisition unit corresponding to the hob temperature image in a circle with a pixel P as the diameter according to the hob installation position. The circle is decomposed into small squares with each being a pixel of 1*1. The data processing module interpolates the data points between N hobs by using the cubic spline interpolation method, interpolates the remaining data points by using the inverse distance weighting method, and converts the temperature values of each data point into color values through a temperature conversion factor, and fills the small squares of pixel 1*1 with the color values to obtain the hob thermal map; the data display module is used to display the hob thermal map in real time.

[0066] Preferably, the data acquisition unit includes a single-chip microcomputer and several temperature sensors. The temperature sensors are installed in the hob barrel and on the shield machine cutter head transmission shaft. There is a wireless transmission module in the temperature sensor. The wireless transmission module is connected to the wireless reception module. The wireless reception module is set on the single-chip microcomputer. The single-chip microcomputer is connected to the industrial control computer through the RS485 interface. The industrial control computer obtains the temperature value measured by the temperature sensor in real time through data parsing, that is, the temperature value of the hob.

[0067] Compared with the prior art, the beneficial effects of the present invention are as follows: The hob temperature is obtained by a temperature sensor and sent to the acquisition unit wirelessly. The acquisition unit receives the sensed data of the temperature, and at the same time processes the received data and forwards it to the industrial control computer. An industrial control software is deployed on the industrial control computer. The software obtains the hob temperature value by establishing a data model and data parsing, and performs interpolation based on the cubic spline interpolation and inverse distance weighted interpolation algorithms. At the same time, according to the temperature conversion color algorithm, the temperature value is converted into a color value, so as to realize the real-time display of the heat map of the hob temperature. The present invention creatively introduces a heat map in the field of tunnel construction. Through research algorithms, the heat map can be displayed in real time. At the same time, through the hob heat map, the heat map can be refreshed in real time, and the temperature information of the entire cutterhead tool can be obtained intuitively and quickly. Furthermore, the temperature of the cutterhead can be overall controlled, the state information of the tool can be overall controlled, and the state of each tool can be analyzed and judged. The tools with abnormal temperature can be focused on, and faults such as cutter caking and stuck rotation can be discovered and eliminated in time. When faults such as cutter caking, eccentric wear, and stuck rotation occur in the tool and are not discovered in time, it will lead to a low tunneling efficiency of the shield machine, and at the same time will seriously damage the tool and reduce the service life of the cutterhead. Therefore, the work efficiency is greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0069] Figure 1 It is a flowchart of the present invention.

[0070] Figure 2 It is a schematic diagram of data parsing of the present invention.

[0071] Figure 3 It is a schematic diagram of the principle of the device of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0072] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0073] Embodiment 1, as Figure 1 shown, the present invention provides a method for real-time display of a hob heat map, including the following steps:

[0074] Step 1: Determine the installation positions of the hob cutters on the cutter head according to the cutter head diagram. The number of hob cutters is N.

[0075] Step 2: Use a temperature sensor to measure the temperature value of the hob cutter in real time.

[0076] Install N temperature sensors on the hob cutter barrel of the cutter head. The acquisition unit regularly acquires the data measured by the temperature sensors and forwards the obtained data to the industrial control computer through the serial port RS485. The industrial control computer parses the data through the RS485 interface to obtain the real-time temperature of each hob cutter, and sets the real-time temperatures of the hob cutters as T1, T2,.., Tn,.., TN respectively.

[0077] According to the installation radius Z, installation angle θ, and installation position coordinates (Z * cosθ, Z * sinθ) on the cutter head provided by the cutter head diagram, determine the installation positions of the hob cutters on the cutter head. Each hob cutter has a cutter barrel, and the temperature sensors are installed in the hob cutter barrel and on the drive shaft of the shield machine cutter head. There is a wireless transmission module in the temperature sensor, which will send the data out wirelessly in real time. The receiving module receives the data in real time. The receiving module is integrated on a PCB circuit board controlled by a single-chip microcomputer (referred to as the acquisition unit). The acquisition unit has an RS485 interface and sends the data to the industrial control computer in real time after parsing according to the Figure 2 coding method. The upper computer software of the industrial control computer obtains the temperature values of each hob cutter through data parsing. From the N hob cutter temperature values, through the trisection interpolation and inverse proportional weight interpolation, and convert the temperature into colors and display them in real time. The hob cutter numbers correspond one by one with the temperature sensor numbers.

[0078] Step 3: Establish a cutter head temperature image, and mark the measured temperature values of the hob cutters in the cutter head temperature image according to the installation positions of the hob cutters on the cutter head.

[0079] (1) Regard the cutter head as a circle, and use a circle with a diameter of pixel P as the cutter head temperature image to store the temperature values of the cutter head. The diameter of the cutter head is D.

[0080] (2) Take the center point of the cutter head as the origin to establish a plane coordinate system; through the installation positions of the hob cutters on the cutter head, the cutter head diameter D, and the pixel P, convert the installation positions of the hob cutters into coordinate points on the plane coordinate system. The ratio R = P / D, and the coordinate points of the hob cutters on the plane coordinate system can be converted into (R * Z * Cosθ, R * Z * Sinθ), that is, hob cutter 1 (X1, Y1), hob cutter 2 (X2, Y2).. hob cutter n (Xn, Yn).. hob cutter N (XN, YN).

[0081] Step 4: Derive the adjacent temperature values of the hob cutters according to the difference algorithm to obtain the temperature values of all pixel points in the cutter head temperature image.

[0082] Divide a circle with a diameter of P pixels into M blocks, each block being 1*1 pixels; the number of hob cutters on the cutter head is N, where N is much smaller than M, and the remaining M - N blocks are used to derive the temperature through interpolation algorithm. A hob cutter can be regarded as a 1*1 pixel point because the difference between the adjacent temperature values derived from the interpolation algorithm and the temperature at this point is very small. Of course, this hob cutter can also be regarded as multiple pixel points. During interpolation calculation, these pixel points do not participate in the calculation, which can reduce the data for interpolation calculation, improve efficiency, and increase real-time performance.

[0083] To ensure the accuracy and efficiency of the interpolation algorithm, two different interpolation algorithms are adopted for the interpolation algorithm, defined as Algorithm A and Algorithm B. Algorithm A is the cubic spline interpolation method, and Algorithm B is the inverse proportional weight method. Among them, Algorithm A is used to interpolate the data points between N hob cutters. Set the number of data points between N hob cutters as R, and Algorithm B is used to interpolate the remaining M - N - R data points. The spline interpolation method is more accurate than the inverse proportional weight method, but at the same time, the algorithm complexity is also higher. In practical engineering applications, the elements between adjacent hob cutters are interpolated using the spline interpolation method, and the inverse proportional weight method is used for the remaining other points, which can not only meet the accuracy required by the project but also take into account the algorithm complexity to ensure the real-time refresh of the heat map.

[0084] The specific steps of Algorithm A are as follows:

[0085] 4.1 Starting from hob cutter 1 (X1, Y1), calculate the distances between hob cutter 1 and hob cutters 2, 3... N as d1, d2... dz (where z = N - 1) and the distances

[0086]

[0087] Among them, X, Y, Xv, and Yv respectively represent the coordinates of two points in the plane rectangular coordinate system; the hob cutter closest to hob cutter 1 is obtained through the distances d1, d2... dz, and the coordinates of the hob cutter set as hob cutter s (2 <= s <= N) are (Xs, Ys).

[0088] 4.2 Interpolate between hob cutter 1 and hob cutter s. If there are S + 1 data points between hob cutter 1 and hob cutter s, there will be a total of S intervals, and thus S segments of curves. Assume that each segment of the curve is S(x). Assume that the x coordinates of this bunch of data points are: x = x0, x1, x2,..xS arranged in ascending order, and the values corresponding to each point are y0, y1, y2,..yS. The installation position of the hob cutter can be determined from the cutter head diagram, and it can be determined that each segment of the curve S(x) satisfies the following three conditions:

[0089] a. In each subinterval [x i , x i+1 (i = 0, 1,…, S - 1), the curve S(x) = Si All (x) are cubic polynomials;

[0090] b. Satisfy S(x i ) = y i (i = 0, 1, …, S - 1);

[0091] c. The curve S(x), the derivative S'(x), and the second derivative S″(x) are all continuous in the interval [x0, x s , that is, the curve S(x) is smooth.

[0092] Then the curve S(x) can be expressed by the following formula:

[0093] S i (x) = a i + b i (x - x i ) + c i (x - x i ) 2 + d i (x - x i ) 3 (2)

[0094] Where a i , b i , c i , d i Are the cubic spline interpolation coefficients of the curve equation between adjacent hob cutters.

[0095] According to conditions a and b of the curve equation characteristics and the continuity of the curve S i (x), we can obtain:

[0096] S i (x i ) = y i

[0097] S i (x i+1 ) = y i+1 (3)

[0098] S i '(x i+1 ) = S i ' +1 (x i+1 )

[0099] S″ i (x i+1 ) = S″ i+1 (x i+1 ) (4)

[0100] According to condition c and combining with the first derivative and second derivative of the curve in formula (2), we can obtain

[0101] S i (x)=a i +b i (x - x i )+c i (x - x i ) 2 +d i (x - x i ) 3

[0102] S i '(x)=b i +2c i (x - x i )+3d i (x - x i ) 2

[0103] S″ i (x)=2c i +6d i (x - x i ) (5)

[0104] For ease of description: Let h i =x i+1 -x i represent the i-th interval. Combining formulas (2) and (3) gives

[0105] a i =y i (6)

[0106]

[0107] Combining (6) and (7) gives

[0108]

[0109] Based on formula (5), we get

[0110]

[0111] S i ' +1 (x i+1 )=b i+1 +2c i+1 (x i+1 -x i+1 )+3d i+1 (x i+1 -x i+1 ) 2 =b i+1 (9)

[0112] Derived from (4) and (9)

[0113]

[0114] Set S″ for convenience of narration i (x i ) = m i And by combining formula (4) and (5), it is derived that:

[0115]

[0116]

[0117] Substituting formula (11) and (12) into formula (8) can be derived:

[0118]

[0119] Substituting formula (11), (12), (13) into formula (10) can obtain

[0120]

[0121] }Since the temperature value between the first and the last hob of the simulated cubic curve is known, that is, interpolation calculation is not required at both ends of the curve, it can be expressed as

[0122] From formula (14) and (15), the system of equations to be solved can be obtained as: (There are as many equations as the number of intervals divided between adjacent hobs. Each curve equation is regarded as a cubic polynomial equation, where n = S)

[0123]

[0124] Solving the above system of equations can obtain the interpolation of each segment. By matrix operation, the values of m0, m1, m2,..., mS are obtained, and then the cubic spline interpolation coefficients a i 、b i 、c i 、d i are obtained. Knowing the cubic spline interpolation coefficients a i 、b i 、c i 、d i the cubic curve equation can be obtained, and by solving successively, the interpolation temperatures can be obtained.

[0125] 4.3 Recursively obtain the differences between hob 2, hob 3,... hob n in turn. At the same time, only one interpolation calculation is allowed for the two hob blades with the closest distance. For example, the hob closest to hob 1 is hob 3. When judging the closest distance of hob 3, hob 1 should be excluded. Find the hob closest to hob 3 from the remaining (n - 2) hob blades, and perform interpolation calculation according to step 4.2.

[0126] The remaining M - N - R data points are interpolated using interpolation algorithm B. The specific steps of algorithm B are as follows:

[0127] For example, if the temperature of point V(Xv, Yv) is Tv, the influence of point V on point P1(X, Y) at a distance d can be calculated by the following formula:

[0128] Tp1 = Tv / d, where d is the distance between the coordinates of two points in the plane, referring to formula (1).

[0129] The final temperature value of point P1 is jointly determined by the known N hob temperature values on the plane, as follows:

[0130]

[0131] Among them, Tn represents the nth temperature of the hob, and dn represents the distance between the nth temperature point of the hob and point p1 when deriving the temperature of the p1th point, 0 < n <= N.

[0132] Derive the interpolation of the M - N - R data points in turn according to formula (16).

[0133] Step 5: Combine the actual project and confirm the temperature - to - color value algorithm based on a large number of tests, and convert the temperature values obtained in step 4 into color values to obtain the hob thermal map. The specific algorithm is as follows:

[0134] (1) Set the color gradient change to C1 (red), C2 (yellow),... C u (orange); u can be set arbitrarily. The larger the value of u, the better the color layering, but at the same time, the algorithm complexity is also high. Considering the project and practical application, u = 3 is used in this case; that is, the colors of the thermal map are between red, yellow, and green.

[0135] (2) Set the maximum hob temperature as Tmax and the minimum as Tmin;

[0136] (3) Any color display is composed of R, G, B, and the range of R, G, B is between [0, 255];

[0137] (4) Calculate the temperature conversion factor Tp = Tn / (Tmax - Tmin); the temperature conversion factor for each pixel is related to the temperature value at that point, ensuring that the colors converted from each temperature value vary within the specified color scale range. The higher the temperature, the redder the color; the lower the temperature, the greener the color. The conversion factor ensures that each temperature value is displayed between red and green colors.

[0138] (5) Obtain the adjacent color scale change algorithm. Taking color scales C u and C u+1 as examples, the specific conversion steps are as follows:

[0139] 5.1 Calculate the color values R, G, B and put them in numerical order

[0140] R = C u .R * (1.0 - T p ) + C u+1 .R * T p

[0141] G = C u .G * (1.0 - T p ) + C u+1 .G * T p

[0142] B = C u .B * (1.0 - T p ) + C u+1 .B * T p

[0143] Among them, C u .R and C u+1 .R respectively represent the red components in color scales C u and C u+1 ; C u .G and C u+1 .G respectively represent the green components in color scales C u and C u+1 ; C u .B and C u+1 .B respectively represent the blue components in color scales C u and C u+1 .

[0144] 5.2 Calculate the display color value of the pixel according to the color values R, G, B using the color value change function Color.FromRgb(R, G, B). Any color is obtained by the color value change function Color.FromRgb(R, G, B), and the color value calculated from the numerical values of the color values R, G, B is between two color scales.

[0145] If there are multiple levels of colors to be displayed, refer to step (5) and loop recursively in turn. The number of recursions is the permutation and combination. The more color levels, the more beautiful the displayed heat map, but it affects the software performance. Combining with the actual engineering application and considering aesthetics and performance, the heat map of this time displays three color levels: red, yellow, and green. That is, step (5) needs to loop times.

[0146] The present invention draws a circular digital image of the entire cutter head on the industrial control computer. The diameter of the circle is P pixels. The circle is decomposed into small squares of 1*1 each. Different small squares are filled with different colors. By analogy, the entire circle will be filled, thus obtaining the hob heat map. The cubic spline interpolation method is used between adjacent hobs. In the middle, it is divided into small squares of 1*1 pixels in turn. The temperature is deduced by using cubic spline interpolation, and then the color is deduced from the temperature. The color value is filled into the small squares of 1*1 pixels of the hob heat map. The total number of small squares divided between all adjacent hobs is R. There are still M - N - R small squares left on the entire circle. The temperature values of these small squares are obtained by the inverse distance weighting method, and then the temperature values are converted into colors.

[0147] Step 6: According to the obtained color values, refresh the M blocks of the hob heat map in turn, so as to realize the real-time display of the heat.

[0148] Embodiment 2

[0149] As Figure 3 shown, a device for real-time display of hob heat map includes a data acquisition unit and an industrial control computer. The data acquisition unit is connected to the industrial control computer. The industrial control computer is provided with a data storage module, a data processing module, and a data display module. The data storage module stores the temperature values of N hobs collected by the data acquisition unit corresponding to the cutter head temperature image of a circle with a diameter of P pixels according to the hob installation position. The circle is decomposed into small squares of pixel 1*1 each. The data processing module interpolates the data points between N hobs by using the cubic spline interpolation method, interpolates the remaining data points by using the inverse proportion weighting method, and converts the temperature values of each data point into color values through a temperature conversion factor, and fills the small squares of 1*1 pixels with the color values to obtain the hob heat map; the data display module is used for real-time display of the hob heat map.

[0150] Further, the data acquisition unit includes a single-chip microcomputer and several temperature sensors. The temperature sensors are installed in the hob barrel and on the cutter head transmission shaft of the shield machine. There is a wireless transmission module in the temperature sensor. The wireless transmission module is connected to the wireless reception module. The wireless reception module is arranged on the single-chip microcomputer. The single-chip microcomputer is connected to the industrial control computer through the RS485 interface. The industrial control computer passes through Figure 2Perform data parsing on the corresponding decoded form shown to obtain the temperature value measured in real time by the temperature sensor, that is, the temperature value of the hob.

[0151] Other implementation methods are the same as those in Embodiment 1.

[0152] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for real-time display of the hob heat map, characterized in that, The steps are as follows: Step 1: Determine the installation position of the hob on the cutter head according to the cutter head diagram; Step 2: Use a temperature sensor to measure the temperature value of the hob in real time; Step 3: Establish a cutter head temperature image, and mark the measured temperature value of the hob in the cutter head temperature image according to the installation position of the hob on the cutter head; Step 4: Deduce the adjacent temperature values of the hob according to the interpolation algorithm to obtain the temperature values of all pixel points in the cutter head temperature image; The method for deducing the adjacent temperature values of the hob according to the interpolation algorithm is: divide the circle of the cutter head temperature image into M blocks of data points, and the pixels of each block of data points are 1*1. Mark the values of the coordinate points at the installation position of the hob or the coordinate points within its neighborhood as the measured temperature value of the hob; use the cubic spline interpolation method to interpolate the data points between N hobs, and use the inverse distance weighting method to interpolate the remaining data points; Step 5: Combine the temperature-to-color value algorithm and convert the temperature value obtained in Step 4 into a color value to obtain a hob heat map; Step 6: Refresh the pixel points of the hob heat map in sequence according to the obtained color value, so as to realize the real-time display of heat; 2. The method for real-time display of the hob heat map according to claim 1, characterized in that Install a temperature sensor on each hob of the cutter head. The real-time temperature values of the hobs measured by the temperature sensor are T1, T2,.., Tn,.., TN respectively; Tn is the temperature value of the nth hob, n = 1 - N, and N is the total number of hobs on the cutter head; the cutter head temperature image is a circle with a diameter of pixel P.

3. The method for real-time display of the hob heat map according to claim 2, wherein, The cutter head diagram provides the hob installation radius Z and the installation angle θ of the hob, and determines the installation position of the hob according to the cutter head radius and the installation angle of the hob; taking the center point of the cutter head as the origin, a plane coordinate system is established; through the installation position of the hob, the cutter head diameter D and the pixel P, the installation position of the hob is converted into the coordinate points on the plane coordinate system: (R1*Z*Cosθ, R1*Z*Sinθ), the ratio R1 = P / D; then the coordinate points of the hob on the cutter head temperature image are respectively: hob 1 is (x1, y1), hob 2 is (x2, y2).. hob n is (x n , y n ),.. hob N is (x N , y N ).

4. The method for real-time display of the hob heat map according to any one of claims 1-3, characterized in that, The implementation method of interpolating the data points between N hobs by the cubic spline interpolation method is: 4.1 Starting from hob 1, calculate the distances between hob 1 and hob 2, hob 3... hob N as d1, d2... dz respectively, where z = N - 1; obtain the hob closest to hob 1 as hob s through the distances d1, d2... dz, 2 <= s <= N; 4.2 Interpolate between hob 1 and hob s. If there are S + 1 data points between hob 1 and hob s, there will be S intervals, that is, S segments of curves are divided; establish a cubic spline curve equation and solve it in sequence to obtain the interpolation for each data point as the temperature value of each data point; 4.3 Loop through steps 4.1 - 4.2 in sequence to obtain the interpolation between two points of hob 2, hob 3... hob n; and only allow one interpolation calculation for the two closest hobs.

5. The method for real-time display of the hob heat map according to claim 4, wherein, The method for establishing the cubic spline curve equation and solving to obtain each interpolation is: Let each curve be S(x), and let the x - coordinates of the data points x0, x1, x2,..x S be arranged in ascending order, and the values corresponding to each point be y0, y1, y2,..y S ; The installation position of the hob determined by the cutter head diagram determines that each curve S(x) satisfies the conditions of the following three curve - equation characteristics: a. In each sub - interval [x i , x i+1 , where i = 0, 1, …, S - 1, the curve S(x)=S i (x) is a cubic polynomial; b. Satisfy S(x i ) = y i ; c. The curve S(x), the derivative S'(x), and the second derivative S”(x) are continuous in the interval [x0, x s , that is, the curve S(x) is smooth; Then the curve S(x) is expressed as: S i (x) = a i + b i (x - x i ) + c i (x - x i ) 2 + d i (x - x i ) 3 ; where a i , b i , c i , d i are the cubic spline interpolation coefficients of the curve equation between adjacent hob cutters, respectively; According to conditions a and b of the curve equation characteristics and curve S i It can be obtained from the continuity of (x): S i (x i ) = y i S i (x i+1 ) = y i+1 ; S′ i (x i+1 ) = S′ i+1 (x i+1 ) S″ i (x i+1 ) = S″ i+1 (x i+1 ); According to condition c and the first derivative and second derivative of curve S(x), it can be obtained that: S i f(x) = a i + b i (x - x i ) + c i (x - x i ) 2 + d i (x - x i ) 3 S′ i f(x) = b i + 2c i (x - x i ) + 3d i (x - x i ) 2 S″ i f(x) = 2c i + 6d i (x - x i ); Let h i = x i+1 - x i represent the i-th segment interval, then it is deduced that: a i = y i 、 Then it is deduced that: Let S″ i (x i ) = m i Then we get: It can be deduced that: It can be obtained Since the temperature values between the first and last hob of the simulated cubic curve are known, that is, interpolation calculation is not required at both ends of the curve, it can be expressed as: The system of equations to be solved can be obtained as: where n = S; The values of m0, m1, m2, ..., mS are obtained through matrix operations, and then the cubic spline interpolation coefficients a i , b i , c i , d i are obtained to get the cubic curve equation, and then each interpolation temperature is obtained by successive solution.

6. The method for real-time display of the hob heat map according to claim 1 or 5, characterized in that, The implementation method of the inverse distance weighting method is: the final temperature value of point p1 is jointly determined by the temperature values of N known hobs on the plane, and Among them, T n represents the temperature value of hob n, and d n represents the distance between the coordinate point of hob n and the p1-th point when deriving the temperature at point p1, where 0 < n <= N; p1 is any one of the remaining data points.

7. The method for real-time display of the hob heat map according to claim 3, characterized in that The implementation method of the temperature-to-color value algorithm in Step 5 is: 1) Set the color level change to color levels C1, C2, and C3. The color levels C1, C2, and C3 are respectively the colors of the hob heat map between red, yellow, and green; 2) Set the maximum value of the temperature value of the hob as Tmax and the minimum value as Tmin; calculate the temperature conversion factor Tp = Tn / (Tmax - Tmin); 3) Calculate the color value of each pixel according to the adjacent color level change algorithm using the temperature conversion factor.

8. The method for real-time display of the hob heat map according to claim 7, characterized in that The implementation method of the adjacent color level change algorithm is as follows: for color levels C u and C u+1 color levels, the conversion steps are as follows: The numerical values of the calculated color values R, G, and B are respectively: R = C u .R * (1.0 - T p ) + C u+1 .R * T p G = C u .G * (1.0 - T p ) + C u+1 .G * T p B = C u .B * (1.0 - T p ) + C u+1 .B * T p Among them, C u .R and C u+1 .R respectively represent the red components in color scales C u and C u+1 ; C u .G and C u+1 .G respectively represent the green components in color scales C u and C u+1 ; C u .B and C u+1 .B respectively represent the blue components in color scales C u and C u+1 ; Calculate the display color value of the pixel point using the color value change function Color.FromRgb(R, G, B) according to the color values R, G, and B; When there are multiple levels of color display, recursively calculate the color values R, G, and B between each color level in sequence.

9. The device for the method of real-time display of the hob heat map according to any one of claims 1-3, 5, 7, and 8, characterized in that, It includes a data acquisition unit and an industrial control computer. The data acquisition unit is connected to the industrial control computer. The industrial control computer is equipped with a data storage module, a data processing module, and a data display module. The data storage module stores the temperature values of N hob cutters collected by the data acquisition unit corresponding to the cutter head temperature image of a circle with a diameter of pixel P according to the hob installation position. The circle is decomposed into small squares of 1*1 pixels each. The data processing module interpolates the data points between N hob cutters using the cubic spline interpolation method, interpolates the remaining data points using the inverse proportional weighting method, and converts the temperature values of each data point into color values through the temperature conversion factor. Fill the small squares of 1*1 pixels with the color values to obtain the hob thermal image; the data display module is used to display the hob thermal image in real time.

10. The device according to claim 9, characterized in that, The data acquisition unit includes a single-chip microcomputer and several temperature sensors. The temperature sensors are installed in the hob cutter barrel and on the shield machine cutter head drive shaft. There is a wireless transmission module inside the temperature sensor. The wireless transmission module is connected to the wireless reception module. The wireless reception module is set on the single-chip microcomputer. The single-chip microcomputer is connected to the industrial control computer through the RS485 interface. The industrial control computer obtains the temperature value measured by the temperature sensor in real time through data parsing, that is, the temperature value of the hob cutter.

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