CN105666246A - Tool parameter measurement device based on CCD and measurement method of device - Google Patents

Abstract

The invention relates to a tool parameter measurement device based on a CCD and a measurement method of the device.The tool parameter measurement device comprises a collection box, a CCD industrial camera, an industrial personal computer and a display, and the CCD industrial camera, the industrial personal computer and the display are sequentially connected; a camera transverse moving mechanism is arranged on a base of the collection box, a camera longitudinal moving mechanism is arranged on the camera transverse moving mechanism, and the CCD industrial camera is installed on the camera longitudinal moving mechanism.When measurement is conducted, a machine tool main shaft does not rotate, and static collecting is conducted; the main shaft collects an image whenever the main shaft rotates by one angle, and peripheral morphology of a tool is collected and stored in the specific location; data processing is conducted on a collected gray image.According to the tool parameter measurement device based on the CCD and the measurement method of the device, the tool parameters are directly measured on a machine tool, tool disassembly is omitted, the precision and efficiency are improved, non-contact measurement is conducted on a digital image based on the CCD, static measurement is conducted on the tool parameters, and the cost is reduced compared with that of a camera needing automatic focusing under rotation; the parameters such as slack length, radius, fillet and form and location tolerance of the tool can be measured.

Description

Based on cutter parameter measuring device and the measuring method thereof of CCD

Technical field

The present invention relates to the measuring apparatus of the geometric parameters such as the outstanding length of a kind of direct accurately acquisition cutter on lathe, radius, fillet, form and position tolerance and measuring method thereof, belong to tool geometrical parameter field of measuring technique.

Background technology

Cutter is used for the professional instrument of processing precise part as numerically-controlled machine, and the height of himself precision directly decides the precision of the precision component of its processing. Current cutting tools measurement method has certain limitation, the first, the numerical control machining center processing that manual measurement cutter parameters is not suitable for current batch production, level of automation is high. Manual detection efficiency is low, precision is low; Tool surface and the feature request precision height processed, surface smoothness requires also high, and traditional method needs to contact survey instrument with tool surface, and cutter figuratrix is had certain damage, thus affects cutter self precision; 2nd, the measuring apparatus proposed at present is not suitable for actual production operating mode. The measuring apparatus proposed at present is under directly cutter is placed on industrial camera mostly. For ensureing that axis system can operate safely and reliably, main shaft handle of a knife cutter bonding surface needs to have high geometric accuracy, height repeats the characteristic such as precision and high rigidity that is installed, and high-speed spindle system dynamics is had important impact by bonding surface; And consider factory's actual production operating mode, cutter is stored in cutter storehouse, main shaft-cutter-handle of a knife bonding surface is located, according to the measurement scheme proposed, need cutter first to unload cutter from cutter storehouse, and then unload from handle of a knife, install every time and will reorientate for twice, degradation in efficiency, and the precision obtaining cutter parameters is had a direct impact.

Summary of the invention

The present invention is directed to the deficiency that existing cutting tools measurement technology exists, it is provided that the cutter parameter measuring device based on CCD that a kind of measuring accuracy height, efficiency are high.

The cutter parameter measuring device based on CCD of the present invention, by the following technical solutions:

This device, comprises collector tank, CCD industrial camera, industrial computer and indicating meter, and CCD industrial camera, industrial computer and indicating meter connect successively;Being provided with camera transverse moving mechanism on the base of collector tank, camera transverse moving mechanism is provided with camera longitudinal moving mechanism, CCD industrial camera is arranged on camera longitudinal moving mechanism.

Also being provided with LED/light source plate in described collector tank, LED/light source plate, for the benefit light that throws light on, makes digital picture background that CCD industrial camera gathers and target boundary obvious, is convenient to image procossing.

Described collector tank arranges casing on base and becomes, and casing comprises all around four side case doors and a top case door.

Described camera transverse moving mechanism, comprises horizontal guide rail, horizontal slide block and horizontal slide block and moves mechanism, and horizontal slide block and horizontal slide block move mechanism and be all arranged on horizontal guide rail, and horizontal slide block moves mechanism with horizontal slide block and is connected. Horizontal guide rail is provided with the horizontal locking screw of the horizontal slide block position of locking. Horizontal slide block moves mechanism and adopts feed screw nut secondary, and horizontal guide rail is also provided with the horizontal scale for observing horizontal slide block position.

Described camera longitudinal moving mechanism, comprise longitudinal guide rail, longitudinal slide block and longitudinal slide block and move mechanism, longitudinal guide rail is arranged on horizontal slide block, and longitudinal slide block and longitudinal slide block move mechanism and be all arranged on longitudinal guide rail, and longitudinal slide block moves mechanism with longitudinal slide block and is connected. Longitudinal slide block moves mechanism and also adopts feed screw nut secondary. The longitudinal locking screw being provided with the longitudinal slide block position of locking on longitudinal guide rail, longitudinal guide rail is also provided with the longitudinal scale for observing longitudinal slide block position.

The measuring method of the above-mentioned cutter parameter measuring device based on CCD, comprises the following steps:

(1) whole device is arranged on platen, makes whole device with lathe X axis and Y-motion, open machine tool chief axis fix a cutting tool just to the case door of collector tank (for vertical lathe, open the upper chamber door of collector tank; For horizontal type machine tool, open the front case door of collector tank);

(2) switch on power, CCD camera is connected with industrial computer and indicating meter, open LED/light source switching plate;

(3) regulating numerically-controlled machine, lift cutter, then adjusting tool X-axis worktable and lathe Y-axis slip plate, make to complete coarse adjustment below whole plant running to cutter; Regulate numerically-controlled machine, cutter is declined, indicating meter demonstrates the complete image of surveyed cutter;

(4) by camera longitudinal moving mechanism, CCD industrial camera is moved up and down, make to move before and after CCD industrial camera by camera transverse moving mechanism, make indicating meter demonstrates the complete image clearly of cutter, complete accurate adjustment;

(5) image is gathered after regulating, in gatherer process, machine tool chief axis non rotating, static collection; Main shaft often turns an angle and gathers an image, completes the collection of cutter circumferential looks and is kept in industrial computer;

(6) the gray-scale map picture gathered is carried out data processing by industrial computer.

In described step (6), the process that the gray-scale map picture gathered carries out data processing is by industrial computer:

1. gray-scale map picture first carries out inter-class variance in maximum kind, than method Iamge Segmentation, slightly extracted at edge;

In maximum kind, inter-class variance is than method: note t is the segmentation threshold of prospect and background, and prospect is counted and accounted for image ratio is w₀, average gray is u₀; Background is counted and accounted for image ratio is w₁, average gray is u₁. Then the overall average gray scale of image is:

U=w₀*u₀+w₁*u₁,

The variance of prospect and background image:

σ²=w₀*(u₀-u)²+w₁*(u₁-u)²=w₀*w₁*(u₀-u₁)²,

Try to achieve σ²Maximum value, obtain threshold value;

2. gaussian filtering, two dimension Gaussian functionCarrying out convolution with gray-scale map picture, F (x, y)=G (x, y) * f (x, y), with stress release treatment, wherein what σ represented is the parameter of Gaussian filter, and its value size determines the smoothness of wave filter;The gray-scale value that f (x, y) puts for (x, y) in image, F (x, y) is the gray-scale value of image after gaussian filtering;

3. gradient direction at canny operator carries out non-maxima suppression, and wherein canny convolution operator is:

$s_x=\left[\begin{array}{cc}-1& 1\\ -1& 1\end{array}\right],s_y=\left[\begin{array}{cc}1& 1\\ -1& -1\end{array}\right],$

4. maximum entropy method (MEM) canny operator edge detection, carries out essence and extracts image border; If gray-scale map picture is of a size of M × N, grey scale change scope is G={0,1 ..., L-1}, gets the threshold value t of threshold value segmentation, two-dimensional histogram is divided into T, B two regions, then the probability distribution in two regions is respectively:

$T:\frac{P_0}{P_T},...,\frac{P_t}{P_T},$

$B:\frac{P_{t+1}}{1-P_T},...,\frac{P_{L-1}}{1-P_T},$

Wherein probability distribution T probability is:

Then the entropy of two probability distribution is:

$H\left(T\right)=-{\mathrm{\Σ}}_{i=0}^t{P}_i{P}_n{\mathrm{lnP}}_i{P}_n,$

$H\left(B\right)=-{\mathrm{\Σ}}_{i=t+1}^{L-1}{P}_i(1-P_{n)}{\mathrm{lnP}}_i(1-P_{n)},$

Defined functionFor the sum of H (T) and H (B), then:

Arg represents rightNegate function;

5. the outstanding long and radius of hough change detection;

P=x*cos (θ)+y*sin (θ),

Wherein θ is that space line crosses the vertical line of initial point and the angle of x-axis positive dirction, and p is the distance of initial point to z, and parameter space just turns into p-θ space, and in plane, point (x, y) corresponds on p-θ plane deformation; Recording and be highly outstanding length, length is diameter;

6. { (x is made_i, y_i) i=1,2,3 ..., n} is for determining the set of point circumferentially in image, and (x, y) is a bit in set, and the equation in parameter system of coordinates (a, b, R) is:

(x-a)²+(y-b)²=R²,

Utilize hough change detection circle to obtain fillet size, and by method of least squares, fillet is carried out matching;

7. the shape appearance figure of the cutter circumferential direction of collection and theoretical cutter image are compared, then obtain the actual tolerance value of relative dimensions.

The present invention adopts and directly surveys cutter parameters on lathe, saves dismounting cutter, it is to increase precision and efficiency, saves manpower and materials; Digital picture based on CCD carries out noncontact measurement, is more suitable for modern automation processing, liberation manpower; Carry out static measurement cutter parameters, need the camera of automatic focusing under comparing rotation, reduce costs; This covering device can measure the parameters such as cutter outstanding length, radius, fillet, form and position tolerance, it may also be useful to has popularity.

Accompanying drawing explanation

Fig. 1 is the internal structure schematic diagram of the cutter parameter measuring device based on CCD of the present invention.

Fig. 2 is the schematic diagram being arranged on lathe based on the cutter parameter measuring device of CCD of the present invention.

In figure: 1. casing, 2. horizontal locking screw, 3. longitudinal leading screw regulates knob, 4. longitudinal guide rail, 5. longitudinal slide block, 6. horizontal leading screw regulates knob, 7.CCD industrial camera, 8.LED light source board, 9. horizontal slide block, 10. longitudinal scale, 11. horizontal guide rails, 12. longitudinal locking screws, 13. horizontal scales, 14. bases, 15. cutters, 16. lathe X-axis worktable, 17. lathe Y-axis slip plate, 18. collector tanks.

Embodiment

As shown in Figure 1, the cutter parameter measuring device based on CCD of the present invention, comprising collector tank 18, CCD industrial camera 7, industrial computer (not shown) and indicating meter (not shown), CCD industrial camera 7, industrial computer and indicating meter connect successively. Collector tank 18 arranges casing 1 and become on its base 14, and casing 1 comprises all around four side case doors and a top case door (saving top case door and a side case door in Fig. 1), and each case door is all movable, can open. Being provided with camera transverse moving mechanism on the base 14 of collector tank 18, camera transverse moving mechanism is provided with camera longitudinal moving mechanism, CCD industrial camera 7 is arranged on camera longitudinal moving mechanism. Also being provided with LED/light source plate 8 in collector tank 18, LED/light source plate 8, for the benefit light that throws light on, makes digital picture background that CCD industrial camera 7 gathers and target boundary obvious, is convenient to image procossing.

Camera transverse moving mechanism, comprises horizontal guide rail 11, horizontal slide block 9 and horizontal slide block and moves mechanism. Horizontal slide block 9 and horizontal slide block move mechanism and are all arranged on horizontal guide rail 11, horizontal slide block 9 moves mechanism with horizontal slide block and is connected, horizontal slide block moves mechanism and adopts feed screw nut secondary, horizontal leading screw is threaded with horizontal slide block 9, one end of horizontal leading screw is provided with horizontal leading screw and regulates knob 6, rotates horizontal leading screw to facilitate. Horizontal guide rail 11 is provided with the horizontal locking screw 2 of horizontal slide block 9 position of locking. Horizontal guide rail 11 is also provided with the horizontal scale 13 for observing horizontal slide block 9 position.

Camera longitudinal moving mechanism comprises longitudinal guide rail 4, longitudinal slide block 5 and longitudinal slide block and moves mechanism, longitudinal guide rail 4 is arranged on horizontal slide block 9, longitudinal slide block 5 and longitudinal slide block move mechanism and are all arranged on longitudinal guide rail 4, and longitudinal slide block 5 moves mechanism with longitudinal slide block and is connected. Longitudinal slide block moves mechanism and also adopts feed screw nut secondary, and longitudinal leading screw is threaded with longitudinal slide block 5, and the upper end of longitudinal leading screw is provided with longitudinal leading screw and regulates knob 3, rotates longitudinal leading screw to facilitate. The longitudinal locking screw 12 being provided with longitudinal slide block 5 position of locking on longitudinal guide rail 4, longitudinal guide rail 4 is also provided with the longitudinal scale 10 for observing longitudinal slide block 5 position.

CCD industrial camera 7 is fixed on longitudinal slide block 5. Compared with moving mechanism's Universal arm, CCD industrial camera 7 adopts the better guide rail type movable mechanism of rigidity. CCD industrial camera 7 can move front and back on horizontal guide rail 11, and can longitudinally move up and down by guide rail 4, moves position by the scale observation on transverse direction guide rail 11 and longitudinal direction guide rail 4, to be that next adjustment is for referencial use.

As shown in Figure 2, being arranged on lathe by collector tank 18, for vertical lathe, the direction of the horizontal guide rail 11 in collector tank 18 is consistent with the direction of lathe Y-axis guide rail. According to concrete practical situation, can rationally place the position of collector tank 18. Considering the mobility of machine tool chief axis, selection collector tank 18 can with lathe X axis and Y-motion, and machine tool chief axis keeps Z axle move up and down and rotate by lathe self time variable control. When measuring cutter parameters, for vertical lathe, open the upper chamber door of collector tank 18; For horizontal type machine tool, open the front case door of collector tank 18. The detailed process of cutter parameter measuring as follows described in:

1. switching on power, CCD camera 7 be connected with industrial computer and indicating meter, open LED/light source plate 8 switch, carry out illumination and mend light, the digital image objects edge that CCD camera 7 is gathered more easily detects, and is convenient to Image semantic classification.

2. regulating numerically-controlled machine, lift cutter 15, then adjusting tool X-axis worktable 16 and lathe Y-axis slip plate 17, make collector tank 18 move to correct position below cutter 15, complete coarse adjustment; Regulate numerically-controlled machine, make cutter 15 drop to correct position, make the complete image at indicating meter display institute's survey cutter 15 position;

3. rotating longitudinal leading screw regulates knob 3 that CCD industrial camera 7 is moved up and down, and screws longitudinal locking screw 12 and locks longitudinal guide rail 4 position; Rotating horizontal leading screw regulates knob 6 to make to move before and after CCD industrial camera 7, screws horizontal locking screw 2 fixed lateral guide rail 11, makes to demonstrate the complete image clearly of cutter 15, complete accurate adjustment;

4. after regulating, gather image, in gatherer process, machine tool chief axis non rotating, static collection; Main shaft often rotates angle acquisition image, completes the collection of cutter circumferential looks and is kept at specified location;

5. pair gray-scale map picture gathered carries out data processing:

1. gray-scale map picture first carries out inter-class variance in maximum kind, than method Iamge Segmentation, slightly extracted at edge;

In maximum kind, inter-class variance is than method: note t is the segmentation threshold of prospect and background, and prospect is counted and accounted for image ratio is w₀, average gray is u₀; Background is counted and accounted for image ratio is w₁, average gray is u₁. Then the overall average gray scale of image is:

U=w₀*u₀+w₁*u₁,

The variance of prospect and background image:

σ²=w₀*(u₀-u)²+w₁*(u₁-u)²=w₀*w₁*(u₀-u₁)²,

Try to achieve σ²Maximum value can obtain threshold value.

2. gaussian filtering, two dimension Gaussian functionCarrying out convolution with gray-scale map picture, F (x, y)=G (x, y) * f (x, y), with stress release treatment, wherein what σ represented is the parameter of Gaussian filter, and its value size determines the smoothness of wave filter; The gray-scale value that f (x, y) puts for (x, y) in image, F (x, y) is the gray-scale value of image after gaussian filtering.

3. gradient direction at canny operator carries out non-maxima suppression, and wherein canny convolution operator is:

$s_x=\left[\begin{array}{cc}-1& 1\\ -1& 1\end{array}\right],s_y=\left[\begin{array}{cc}1& 1\\ -1& -1\end{array}\right],$

4. maximum entropy method (MEM) canny operator edge detection, carries out essence and extracts image border; If gray-scale map picture is of a size of M × N, grey scale change scope is G={0,1 ..., L-1}, gets the threshold value t of threshold value segmentation, two-dimensional histogram is divided into T, B two regions, then the probability distribution in two regions is respectively:

$T:\frac{P_0}{P_T},...,\frac{P_t}{P_T},$

$B:\frac{P_{t+1}}{1-P_T},...,\frac{P_{L-1}}{1-P_T},$

Wherein probability distribution T probability is

Then the entropy of two probability distribution is:

$H\left(T\right)=-{\mathrm{\Σ}}_{i=0}^t{P}_i{P}_n{\mathrm{lnP}}_i{P}_n,$

$H\left(B\right)=-{\mathrm{\Σ}}_{i=t+1}^{L-1}{P}_i(1-P_{n)}{\mathrm{lnP}}_i(1-P_{n)},$

Defined functionFor the sum of H (T) and H (B), then:

Arg represents rightNegate function.

5. the outstanding long and radius of hough change detection;

P=x*cos (θ)+y*sin (θ),

Wherein θ is that space line crosses the vertical line of initial point and the angle of x-axis positive dirction, and p is the distance of initial point to z, and parameter space just turns into p-θ space, and in plane, point (x, y) corresponds on p-θ plane deformation; Recording and be highly outstanding length, length is diameter.

6. { (x is made_i, y_i) i=1,2,3 ..., n} is for determining the set of point circumferentially in image, and (x, y) is a bit in set, and the equation in parameter system of coordinates (a, b, R) is:

(x-a)²+(y-b)²=R²,

Utilize hough change detection circle to obtain fillet size, and by method of least squares, fillet is carried out matching.

7. the shape appearance figure of the cutter circumferential direction of collection and theoretical cutter image are compared, then can obtain the actual tolerance value of relative dimensions.

The present invention adopts non-contact measurement mode, by the optical system being made up of CCD camera, camera lens etc., when not contacting with cutter measured surface, shape characteristic image on shooting cutter circumferential surface different positions fast, captured image is sent to industrial computer in real time, then by machine vision and image processing techniques, thus obtain the geometric parameters such as the outstanding length of measured cutter, radius, fillet, form and position tolerance, realize intelligence and survey cutter, save manpower and materials, it is to increase working (machining) efficiency. Whole measuring process completes automatically according to process of measurement, need not manual intervention, structure is simple, easily operation, easily grasps.

Claims (9)

1., based on a cutter parameter measuring device of CCD, comprise collector tank, CCD industrial camera, industrial computer and indicating meter, it is characterized in that: CCD industrial camera, industrial computer and indicating meter connect successively; Being provided with camera transverse moving mechanism on the base of collector tank, camera transverse moving mechanism is provided with camera longitudinal moving mechanism, CCD industrial camera is arranged on camera longitudinal moving mechanism.

2. the cutter parameter measuring device based on CCD according to claim 1, is characterized in that: be also provided with LED/light source plate in described collector tank.

3. the cutter parameter measuring device based on CCD according to claim 1, is characterized in that: described collector tank arranges casing on base and becomes, and casing comprises all around four side case doors and a top case door.

4. the cutter parameter measuring device based on CCD according to claim 1, it is characterized in that: described camera transverse moving mechanism, comprise horizontal guide rail, horizontal slide block and horizontal slide block and move mechanism, horizontal slide block and horizontal slide block move mechanism and are all arranged on horizontal guide rail, and horizontal slide block moves mechanism with horizontal slide block and is connected.

5. the cutter parameter measuring device based on CCD according to claim 4, is characterized in that: be also provided with the horizontal scale for observing horizontal slide block position on horizontal guide rail.

6. the cutter parameter measuring device based on CCD according to claim 1, it is characterized in that: described camera longitudinal moving mechanism, comprise longitudinal guide rail, longitudinal slide block and longitudinal slide block and move mechanism, longitudinal guide rail is arranged on horizontal slide block, longitudinal slide block and longitudinal slide block move mechanism and are all arranged on longitudinal guide rail, and longitudinal slide block moves mechanism with longitudinal slide block and is connected.

7. the cutter parameter measuring device based on CCD according to claim 7, is characterized in that: be also provided with the longitudinal scale for observing longitudinal slide block position on longitudinal guide rail.

8., based on a measuring method for the cutter parameter measuring device of CCD described in claim 1, it is characterized in that, comprise the following steps:

(1) whole device is arranged on platen, makes whole device with lathe X axis and Y-motion, open machine tool chief axis fix a cutting tool just to the case door of collector tank;

(2) switch on power, CCD camera is connected with industrial computer and indicating meter, open LED/light source switching plate;

(3) regulating numerically-controlled machine, lift cutter, then adjusting tool X-axis worktable and lathe Y-axis slip plate, make to complete coarse adjustment below whole plant running to cutter; Regulate numerically-controlled machine, cutter is declined, indicating meter demonstrates the complete image of surveyed cutter;

(4) by camera longitudinal moving mechanism, CCD industrial camera is moved up and down, make to move before and after CCD industrial camera by camera transverse moving mechanism, make indicating meter demonstrates the complete image clearly of cutter, complete accurate adjustment;

(5) image is gathered after regulating, in gatherer process, machine tool chief axis non rotating, static collection; Main shaft often turns an angle and gathers an image, completes the collection of cutter circumferential looks and is kept in industrial computer;

(6) the gray-scale map picture gathered is carried out data processing by industrial computer.

9. according to claim 1 based on the measuring method of cutter parameter measuring device of CCD, it is characterized in that, in described step (6), the process that the gray-scale map picture gathered carries out data processing is by industrial computer:

1. gray-scale map picture first carries out inter-class variance in maximum kind, than method Iamge Segmentation, slightly extracted at edge;

In maximum kind, inter-class variance is than method: note t is the segmentation threshold of prospect and background, and prospect is counted and accounted for image ratio is w₀, average gray is u₀; Background is counted and accounted for image ratio is w₁, average gray is u₁. Then the overall average gray scale of image is:

U=w₀*u₀+w₁*u₁,

The variance of prospect and background image:

σ²=w₀*(u₀-u)²+w₁*(u₁-u)²=w₀*w₁*(u₀-u₁)²,

Try to achieve σ²Maximum value, obtain threshold value;

2. gaussian filtering, two dimension Gaussian functionCarrying out convolution with gray-scale map picture, F (x, y)=G (x, y) * f (x, y), with stress release treatment, wherein what σ represented is the parameter of Gaussian filter, and its value size determines the smoothness of wave filter; The gray-scale value that f (x, y) puts for (x, y) in image, F (x, y) is the gray-scale value of image after gaussian filtering;

3. gradient direction at canny operator carries out non-maxima suppression, and wherein canny convolution operator is:

$S_x=\left[\begin{array}{cc}-1& 1\\ -1& 1\end{array}\right],S_y=\left[\begin{array}{cc}1& 1\\ -1& -1\end{array}\right],$

4. maximum entropy method (MEM) canny operator edge detection, carries out essence and extracts image border; If gray-scale map picture is of a size of M × N, grey scale change scope is G={0,1 ..., L-1}, gets the threshold value t of threshold value segmentation, two-dimensional histogram is divided into T, B two regions, then the probability distribution in two regions is respectively:

$T:\frac{P_0}{P_T},...,\frac{P_t}{P_T},$

$B:\frac{P_{t+1}}{1-P_T},...,\frac{P_{L-1}}{1-P_T},$

Wherein probability distribution T probability is:

Then the entropy of two probability distribution is:

$H\left(T\right)=-{\mathrm{\Σ}}_{i=0}^t{P}_i{P}_n\ln P_i{P}_n,$

$H\left(B\right)=-{\mathrm{\Σ}}_{i=t+1}^{L-1}{P}_i(1-P_{n)}\ln P_i(1-P_{n)},$

Defined functionFor the sum of H (T) and H (B), then:

Arg represents rightNegate function;

5. the outstanding long and radius of hough change detection;

P=x*cos (θ)+y*sin (θ),

Wherein θ is that space line crosses the vertical line of initial point and the angle of x-axis positive dirction, and p is the distance of initial point to z, and parameter space just turns into p-θ space, and in plane, point (x, y) corresponds on p-θ plane deformation; Recording and be highly outstanding length, length is diameter;

6. { (x is made_i, y_i) i=1,2,3 ..., n} is for determining the set of point circumferentially in image, and (x, y) is a bit in set, and the equation in parameter system of coordinates (a, b, R) is:

(x-a)²+(y-b)²=R²,

Utilize hough change detection circle to obtain fillet size, and by method of least squares, fillet is carried out matching;

7. the shape appearance figure of the cutter circumferential direction of collection and theoretical cutter image are compared, then obtain the actual tolerance value of relative dimensions.