A method of ice blade profile measurement and cutting optimization and an ice blade cutting device

Abstract

This invention discloses an optimization method and device for ice skate contour cutting, belonging to the field of CNC machining systems. It includes: fitting a measured template ice skate contour curve and saving the template ice skate fitting curve; fitting a measured re-grinding ice skate contour curve in the same way as the template ice skate; projecting the template ice skate fitting curve and the re-grinding ice skate fitting curve onto the same coordinate system; translating and rotating the template ice skate fitting curve to minimize the area between it and the re-grinding ice skate fitting curve; at this point, the trajectory of the template ice skate in this coordinate system is the optimal cutting path for re-grinding the ice skate. This invention uses an ice skate cutting trajectory that translates along with the re-grinding ice skate clamping position, closely following the ice skate blade contour, solving the problem of ice skate grinding trajectory deviation due to inconsistent ice skate clamping; because the area between the optimal re-grinding ice skate cutting path and the re-grinding ice skate fitting curve is minimized, the amount of material removed when cutting the template ice skate contour onto the re-grinding ice skate can be minimized.

Description

Technical Field

[0001] This invention belongs to the field of CNC system machining, and more specifically, relates to a method for ice skate contour measurement and cutting optimization and an ice skate cutting device. Background Technology

[0002] From the perspective of the development of ice skating, ice skates are the foundation of ice sports. Whether it's speed skating, figure skating, ice dancing, ice bouldering, or ice hockey, none of these can be performed without ice skates. With the development needs of my country's ice skate industry, there is an urgent need to develop a device capable of high-precision, diversified processing and repair of ice skates. The most crucial technology in developing such a device is the measurement and optimization of the ice skate profile curve to determine a reasonable processing trajectory.

[0003] Existing technologies also contain numerous studies on ice skate profile measurement and cutting optimization methods. For example, the non-patent literature "Research on Measurement and Data Processing of Ice Skate Arc" uses the least squares method based on the theory of contact measurement to process the measurement data of the ice skate arc, obtaining parameters such as the arc radius and apex position of the ice skate, thus deriving important parameters for ice skate cutting. However, this method has the following problems: Problem 1: The low measurement efficiency and poor accuracy of contact probes cannot meet current process requirements. Current ice skates generally have a dozen or even twenty arc segments, or even non-circular profiles. Contact probes cannot achieve high-precision, high-density point measurement, and they are prone to wear, causing equipment errors. Problem 2: If the ice skate is heavily worn, the quadratic approximation method cannot accurately determine the apex position. Problem 3: Without effective smoothing at the connection between two arc segments, the generated machining trajectory will result in poor surface smoothness of the ice skate. Non-patent literature such as "Research on Measurement and Machining Technology of Ice Blade Arc Grinding System", "Development of Portable CNC Ice Blade Grinding Machine", and "Research on Measurement Technology of Speed ​​Skating Ice Blades" mainly studied ice blade measurement fitting methods, with less research on ice blade contour cutting optimization methods. In reality, due to the lack of close fit between the designed cutting trajectory and the ice blade, ice blade measurement and ice blade grinding are separated, resulting in a situation where measurement is possible but grinding is not. Summary of the Invention

[0004] To address the shortcomings and improvement needs of existing technologies, this invention provides a method for measuring and optimizing the ice skate profile and an ice skate cutting device. The purpose is to achieve integrated measurement and grinding design and optimize the ice skate machining trajectory so that the cutting path is more closely aligned with the ice skate surface.

[0005] To achieve the above objectives, according to a first aspect of the present invention, a method for ice skate profile measurement and cutting optimization is provided, the method comprising:

[0006] Preparation stage: Fit the measured template ice skate profile curve and save the template ice skate fitted curve;

[0007] Cutting optimization stage: Fit the measured contour curve of the ice skate for sharpening, and the fitting method is the same as that of the template ice skate; project the template ice skate fitting curve and the sharpening ice skate fitting curve onto the same coordinate system; translate and rotate the template ice skate fitting curve to minimize the area between the two fitting curves. The contour trajectory of the template ice skate in this coordinate system is the optimal cutting path for sharpening the ice skate.

[0008] Preferably, the method for measuring the ice skate profile curve is as follows:

[0009] After the ice skate is placed horizontally, a line light source is projected above one side of the ice skate. The line light source consists of a row of several equidistant light spots.

[0010] The position of the ice skate edge is calculated by the number of consecutive light spots projected onto the ice skate and the spacing between the light spots; the contour curve of the ice skate is obtained by continuously measuring multiple points at equal intervals.

[0011] Beneficial Effects: This invention proposes a novel method for measuring the contour curve of an ice skate. It employs a "continuous effective light source method" to collect the skate's contour data. Since the light spot projected onto the skate can return valid data, while the light spot reflected from the suspended area is outside the effective measurement range and cannot return valid data, this invention uses a continuous effective light source method where the light spot projected onto the skate must be continuous (if there are alternating valid and invalid light spots, this segment of returned light spot is considered invalid, eliminating interference from suspended objects). Therefore, compared to existing height measurement methods, it has the advantage of strong anti-interference capability.

[0012] Preferably, the formula for calculating the contour curve of the ice skate by continuously measuring multiple points at equal intervals is as follows:

[0013]

[0014] D i =S*M / N i

[0015] Among them, (x i ,y i () represents the position of the i-th measurement point in the machine tool coordinate system, (X) p ,Y P H represents the position of the measurement reference point in the machine tool coordinate system. d D represents the measurement interval. i The position of the i-th measurement point relative to the measurement reference point, H represents the length of the ice skate blade, S represents the number of consecutive light spots projected onto the ice skate blade, M represents the measurement width of the line laser probe itself, and N represents the position of the ith measurement point relative to the reference point. i This represents the number of effective light spots projected by the i-th line light source.

[0016] Beneficial effect: The trajectory of the ice blade profile in the machine tool coordinate system can be obtained from the measurement data of the line laser probe through the above calculation formula.

[0017] Preferably, the fitting employs an improved third-order B-spline fitting, comprising:

[0018] Remove n points from the head of the ice skate profile curve and m points from the tail to obtain imn measurement points;

[0019] The profile curve of the ice skate after removing the head and tail is fitted with a third-order B-spline.

[0020] Beneficial effects: This invention uses an improved third-order B-spline to fit the contour curve. Since the head and tail positions of the ice skate contour are non-grinding areas and the shape is irregular, it is easy to affect the overall contour fitting accuracy. The "head and tail removal" third-order B-spline fitting is used to ensure that the cutting trajectory is smooth and the fitted curve is closer to the actual measured curve, thereby reducing the fitting error.

[0021] Preferably, the translational rotation of the template ice skate fitting curve minimizes the area between it and the ice skate sharpening fitting curve. The trajectory of the template ice skate in this coordinate system is then the optimal cutting path for sharpening the ice skate, including:

[0022] Take points one by one in the fitting curve of the ice skate sharpening process as the center of rotation of the fitting curve of the template ice skate.

[0023] By translating and rotating the template ice skate, the fitted curve is calculated, and the minimum area between the two curves corresponding to each center of rotation is determined.

[0024] The minimum area between curves corresponding to all centers of rotation is found using the quadratic minimum method.

[0025] The optimal translation position and rotation angle for fitting the template ice skate curve are derived from the minimum value.

[0026] Beneficial effects: This invention uses the quadratic minimum method to translate and rotate the template ice skate curve to minimize the area between it and the ice skate grinding curve. At this point, the trajectory of the template ice skate in this coordinate system is the optimal cutting path for grinding the ice skate. Since the area between the optimal cutting path for grinding the ice skate and the fitted curve of the ice skate grinding is minimized, the amount of cutting can be minimized when cutting the outline of the template ice skate on the ice skate grinding.

[0027] Preferably, the minimum value D of the area between the minimum curves corresponding to all the centers of rotation is... min The calculation process is as follows:

[0028]

[0029] D k =min θ Dθ , θ∈(0°,360°)

[0030]

[0031]

[0032] Among them, D k D represents the area between the smallest curves corresponding to the kth centroid. θ D represents the area between the two curves after rotation by an angle θ. min D represents k The minimum value in, Indicates intermediate variables. This represents the curve coordinates after rotating the template-fitted curve by an angle θ. This represents the coordinates of the fitted curve for sharpening ice skates, ΔX. b2 ΔY B2 These represent the XY coordinate translation amounts of the fitted curve for sharpening ice skates.

[0033] Beneficial effects: By calculating D min Then the corresponding minimum included angle θ can be obtained. min and center of gravity k min Value, determined by θ min k min The optimized trajectory function for ice skate cutting is obtained.

[0034] Preferably, the ice skate cutting trajectory optimization function is:

[0035]

[0036]

[0037]

[0038] in, This represents the optimized grinding trajectory. This represents the fitted curve of the template ice skate, ΔX. B1 ΔY B1 θ represents the XY coordinate translation of the fitted curve of the template ice skate. min k represents the rotation angle corresponding to the minimum area between curves. min This represents the centroid of rotation corresponding to the minimum area between curves. This represents the coordinate value of the center of gravity of the template ice skate when the area between curves is minimized. This represents the coordinate value of the center of gravity of the ice skate rotation when the area between the curves is minimized.

[0039] Beneficial effect: The above functions can directly generate machining G-code (machine tool motion control instructions).

[0040] Preferably, the beginning and end of the ice skate are completed based on the linear relationship of the fitted curve of the template ice skate to obtain a complete ice skate cutting path.

[0041] To achieve the above objectives, according to a second aspect of the present invention, an ice skate cutting device is provided, the device comprising: a computer-readable storage medium, a processor, a measuring component, and a cutting component;

[0042] The measuring component is used to measure the contour curve of the ice skate and send it to the processor;

[0043] The computer-readable storage medium is used to store executable instructions;

[0044] The processor is configured to read executable instructions stored in the computer-readable storage medium, execute the ice skate profile measurement and cutting optimization method described in the first aspect, and obtain the optimal cutting path for sharpening the ice skate;

[0045] The cutting assembly is used to cut the ice skate according to the optimal cutting path for sharpening the ice skate.

[0046] Beneficial effects: The ice skate cutting device integrates the probe control module, data fitting and optimization calculation module, automatic conversion of machining trajectory into machining G-code (machine tool motion control instructions), and graphic simulation module into a three-axis CNC system, realizing one-click measurement, one-click optimization, and one-click grinding, simplifying the operation process.

[0047] Preferably, the measuring component is a line laser probe mounted on one side of the spindle of the grinding machine.

[0048] In summary, the above-described technical solutions conceived in this invention can achieve the following beneficial effects:

[0049] This invention proposes an optimization method for ice skate profile cutting. The method involves projecting the fitted curves of two ice skates onto the same coordinate system, and translating and rotating the fitted curve of the template ice skate to minimize the area between it and the fitted curve of the grinding ice skate. The profile trajectory of the template ice skate in this coordinate system then becomes the optimal cutting path for grinding the ice skate. Specifically, the ice skate cutting trajectory is translated as the grinding ice skate clamping position moves, closely conforming to the ice skate blade profile, thus solving the problem of inconsistent ice skate clamping and deviation of the grinding trajectory. Furthermore, because the area between the optimal cutting path for grinding the ice skate and the fitted curve of the grinding ice skate is minimized, the amount of material removed when cutting the profile of the template ice skate onto the grinding ice skate is ensured to be minimized. Attached Figure Description

[0050] Figure 1 The present invention provides a flowchart of an ice skate profile measurement and cutting optimization method.

[0051] Figure 2A schematic diagram illustrating the effective light source measurement principle provided by this invention.

[0052] Figure 3 This is a schematic diagram showing the two fitted curves projected onto the same coordinate system, as provided by the present invention.

[0053] Figure 4 This is a schematic diagram of the area of ​​the first minimum included angle of the center of gravity provided by the present invention.

[0054] Figure 5 A schematic diagram of the optimal cutting curve provided by the present invention.

[0055] Figure 6 This is a report on the cutting optimization results provided for this invention. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0057] like Figure 1 As shown, this invention provides a method for ice skate profile measurement and cutting optimization, the method comprising:

[0058] Phase 1: Measurement, fitting, and archiving of the prototype ice skate profile curve.

[0059] Step 1: Establish the ice blade measurement coordinate system based on the machine tool coordinates, and set the center point of the line laser as the measurement reference point.

[0060] Step 2: Establish an ice skate grinding coordinate system based on the machine tool coordinate system, and calculate the relationship between ice skate measurement and ice skate grinding in the machine tool coordinate system. This relationship is then used to transform the optimized measurement trajectory into the machine tool grinding trajectory.

[0061] Step 3: Measure the profile curve of the template ice skate.

[0062] Step 4: Perform "head and tail removal" third-order B-spline fitting on the contour curve of the template ice skate.

[0063] Step 5: Archive the template ice skate fitting curve.

[0064] Phase 2: Measure and grind the ice skate profile to optimize the grinding trajectory.

[0065] Step 1: Measure the profile curve of the ice skate and perform B-spline fitting under the same conditions.

[0066] Step 2: Project the template ice skate and the contour curve of the sharpened ice skate in the coordinate system established in Step 1.

[0067] Step 3: Select points one by one in the fitted curve of the ice skate for the template ice skate as the center of rotation of the fitted curve; translate and rotate the template ice skate, and calculate the minimum area between the two curves corresponding to each center of rotation.

[0068] Step 4: Using the quadratic minima method, find the minimum value of the area between the smallest curves corresponding to all rotational centroids. From this minimum value, derive the optimal translation position and rotation angle of the template ice skate fitting curve.

[0069] Step 5: Obtain the optimal cutting path of the ice skate from the best translation position and rotation angle obtained in Step 9.

[0070] The third stage: generating machining G-code from the ice skate grinding trajectory.

[0071] Step 1: Based on the linear relationship of the template ice skate fitting curve in Step 8, complete the beginning and end of the ice skate to obtain the complete ice skate cutting path.

[0072] Step 2: Generate machining G-code based on the positional relationship between ice blade measurement and ice blade grinding in the machine tool coordinate system and the optimized ice blade grinding trajectory function.

[0073] Ice skate profile measurement

[0074] This invention proposes a novel method for measuring the contour curve of ice skates, named the "continuous effective light source method." The contour of the ice skate is acquired using the "continuous effective light source method." For example... Figure 2 As shown, the ice skate is placed horizontally, and the probe projects a line light source (consisting of a row of several equidistant light spots) above one side of the ice skate. The light spots projected onto the ice skate return valid data, while those projected onto the suspended area do not. Therefore, the edge position of the ice skate can be calculated by the number of consecutive light spots projected onto the ice skate and the spacing between them; then, the contour curve of the ice skate can be obtained by continuous measurements at equal intervals. This invention uses a continuous valid light source method, where the light spots projected onto the ice skate must be continuous (if valid and invalid light spots alternate in between, this segment of return light spots is considered invalid, excluding interference from suspended objects). Therefore, compared to existing height measurement methods, it has the advantage of strong anti-interference capability.

[0075] Given that the line laser projects N light spots with a measurement width of M (mm) and the spacing between each spot is M / N; and S light spots are projected onto the ice skate blade, then the relative position D of the ice skate blade edge is determined. i :

[0076] D i =S*M / N i (1)

[0077] The center point of the set laser line is used as the measurement reference (X). P ,Y P The ice skate length is H, and the measurement interval is H. d Measure i points consecutively (i = 0, 1, 2, ..., H / H) d Obtain the ice skate outline curve:

[0078]

[0079] Ice skate cutting trajectory optimization

[0080] Optimizing the cutting trajectory of an ice skate requires cutting a smooth template ice skate profile curve on the sharpened ice skate blade while minimizing the amount of material removed. Therefore, this invention first employs a "head-and-tail removal" third-order B-spline fitting technique to achieve a smooth cutting trajectory. This "head-and-tail removal" is used because the head and tail positions of the ice skate profile are non-grinding areas, and irregular shapes can easily affect fitting accuracy. Secondly, as... Figure 3 As shown, the fitted curves of the template ice skate and the ice skate for sharpening are projected onto the same coordinate system. The template ice skate curve is translated and rotated using the quadratic minimum method to minimize the area between it and the ice skate for sharpening. The trajectory of the template ice skate in this coordinate system is the optimal cutting path for sharpening the ice skate.

[0081] Assuming n points are removed from the head and m points from the tail (based on the characteristics of ice skates, 5mm is removed from the head and 6mm from the tail, as the irregular shape of the non-grinding area affects the fitting accuracy), and the number of measurement points is i, the third-order B-spline fitting curves of the template ice skate and the re-grinding ice skate are as follows:

[0082]

[0083]

[0084] Fitting curves for sharpening ice skates Points are selected one by one in the middle as the centroids of rotation for the fitting curve of the template ice skate. Translate and rotate the template skate blade curve, and calculate the minimum area D between the two curves at each center of rotation. k ,like Figure 4 As shown:

[0085] (1) Translate the curve to move the center of gravity to the origin (0,0):

[0086]

[0087]

[0088]

[0089]

[0090] (2) Curve The curve is obtained by rotating the coordinate system by an angle θ ∈ (0°, 360°) around the origin:

[0091]

[0092] (3) Calculate the curve and Area between curves D θ :

[0093]

[0094]

[0095] (4) Calculate the area D of the minimum included angle corresponding to the kth centroid. k :

[0096] D k =min θ D θ , θ∈(0°,360°) (12)

[0097] (5) The area of ​​the smallest included angle D corresponding to the imn centroids. K Find the minimum value D min :

[0098] D min =min k D k ,(k=n,n+1,n+2…,im) (13)

[0099] like Figure 5 As shown, by D min The corresponding minimum included angle θ min and k min The value can be used to obtain the ice skate cutting optimization trajectory function:

[0100]

[0101] in, These are the coordinates of the center of gravity of the sample ice skate. The coordinates corresponding to the center of gravity of the ice skate rotation for sharpening.

[0102] The Heilong Ice Skate Manufacturing Co., Ltd. proposed a contour accuracy of less than 0.3mm (civilian use), while the State General Administration of Sport proposed a contour accuracy of less than 0.01mm (athlete-specific use). Taking an ice skate provided by Heilong Ice Skate Manufacturing Co., Ltd. and grinding it using the method of this invention, the roundness (contour accuracy) of the ground ice skate, measured by a Renishaw coordinate measuring machine, was only 0.0066mm. Figure 6 As shown.

[0103] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for measuring ice skate profile and optimizing cutting, characterized in that, The method includes: Preparation stage: Fit the measured template ice skate profile curve and save the template ice skate fitted curve; Cutting optimization stage: Fit the measured profile curve of the honed ice skate, and the fitting method is consistent with that of the template ice skate; project the fitting curve of the template ice skate and the fitting curve of the honed ice skate onto the same coordinate system; Take points one by one in the fitting curve of the ice skate sharpening process as the center of rotation of the fitting curve of the template ice skate. By translating and rotating the template ice skate, the fitted curve is calculated, and the minimum area between the two curves corresponding to each center of rotation is determined. The minimum area between curves corresponding to all centers of rotation is found using the quadratic minimum method. The optimal translation position and rotation angle for fitting the template ice skate curve are derived from the minimum value.

2. The method as described in claim 1, characterized in that, The method for measuring the profile curve of an ice skate is as follows: After the ice skate is placed horizontally, a line light source is projected above one side of the ice skate. The line light source consists of a row of several equidistant light spots. The position of the ice skate edge can be calculated by the number of consecutive light spots projected onto the ice skate and the spacing between the light spots; The contour curve of the ice skate is obtained by continuously measuring multiple points at equal intervals.

3. The method as described in claim 2, characterized in that, The formula for calculating the contour curve of an ice skate by continuously measuring multiple points at equal intervals is as follows: in, In the machine tool coordinate system, the first... Location of each measurement point Indicates the position of the measurement reference point in the machine tool coordinate system. Indicates the measurement interval. Indicates the first The position of each measurement point relative to the measurement reference point Indicates the length of the ice skate. This indicates the number of consecutive light spots projected onto the ice skate blade. This indicates the measurement width of the line laser probe itself. Indicates the first The number of effective light spots projected by a line light source.

4. The method as described in claim 2, characterized in that, The fitting employs an improved third-order B-spline fitting method, including: Remove the head of the ice skate's outline curve. One dot, remove the tail. 1 point, get Number of measurement points; The profile curve of the ice skate after removing the head and tail was fitted with a third-order B-spline.

5. The method as described in claim 1, characterized in that, The minimum value of the area between the minimum curves corresponding to all the centers of rotation. The calculation process is as follows: ， ， θ∈(0 o ,360 o ) in, Indicates the first The area between the smallest curves corresponding to each centroid. Indicates rotation The area between the two curves after the angle. express The minimum value in, Indicates intermediate variables. Indicates the rotation of the template fitting curve Curve coordinates after angle This represents the coordinates of the fitted curve for sharpening ice skates. These represent the XY coordinate translation amounts of the fitted curve for sharpening ice skates.

6. The method as described in claim 5, characterized in that, The optimal trajectory function for ice skate cutting is: in, This represents the optimized grinding trajectory. This represents the fitted curve of the template ice skate. , This represents the XY coordinate translation of the fitted curve of the template ice skate. This represents the rotation angle corresponding to the minimum area between curves. This represents the centroid of rotation corresponding to the minimum area between curves. , This represents the coordinate value of the center of gravity of the template ice skate when the area between curves is minimized. , This represents the coordinate value of the center of gravity for grinding the ice skate when the area between the curves is minimized.

7. The method according to any one of claims 4 to 6, characterized in that, By completing the beginning and end of the ice skate based on the linear relationship of the fitted curve of the template ice skate, a complete ice skate cutting path can be obtained.

8. An ice skate cutting device, characterized in that, The device includes: a computer-readable storage medium, a processor, a measuring component, and a cutting component; The measuring component is used to measure the contour curve of the ice skate and send it to the processor; The computer-readable storage medium is used to store executable instructions; The processor is configured to read executable instructions stored in the computer-readable storage medium, execute the ice skate profile measurement and cutting optimization method according to any one of claims 1 to 7, and obtain the optimal cutting path for sharpening the ice skate; The cutting assembly is used to cut the ice skate according to the optimal cutting path for sharpening the ice skate.

9. The ice skate cutting device as described in claim 8, characterized in that, The measuring component is a line laser probe mounted on one side of the spindle of the grinding machine.

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