A method for discriminating free edges of ship components and generating grinding control instructions

Abstract

The present invention discloses a method for discriminating free edges of ship components and generating grinding control instructions, which includes: S1, according to the common characteristic that free edges all contain arc lines, a first-round discrimination is carried out to eliminate the cutting arc starting with a smaller radius and the arc-shaped outer edge with a larger radius in the ship component model, and the arc free edges are screened out; S2, on the basis of discriminating the arc free edges, a second-round discrimination is carried out to eliminate the component edge lines that are not connected or connected but not tangent to the arc free edges, and the straight free edges are screened out; S3, based on the screening of the arc free edges and the straight free edges in the ship component model, the free edge coordinate data is obtained at the same time. Based on the line segment type, coordinate data, and the mutual relationship of line segments, the grinding equipment is used to execute line segment grouping, grinding motion planning, and automatically generate free edge grinding control instructions. The present invention realizes the automatic generation of edge grinding control instructions, reduces the programming error rate, reduces the programming workload, has high grinding intelligence, and reduces the grinding idle travel distance.

Description

Technical Field

[0001] The present invention belongs to the technical field of operations / machine tools / milling, and particularly relates to a method for discriminating free edges of ship components based on a ship component model and generating grinding control instructions. Background Art

[0002] Performing filleting on the free edges of steel components can improve the painting integrity of the components and extend their service life. Currently, in the fields of domestic ships, bridges, steel structures, etc., the filleting of large-sized component free edges basically relies on manual labor, with chamfering tools such as hand-held milling cutters moving along the free edges of the components. With the development of automation technology and the gradual emergence of social problems such as difficult recruitment and high labor costs, automatic chamfering equipment has been gradually developed and applied in actual production.

[0003] According to the research situation of domestic large shipyards, CAM technology is relatively mature in the field of cutting machines, and the supporting software of the cutting machine can generate the execution program of the cutting machine according to the workpiece model. However, the grinding operation is only for the free edges of the ship structure. Currently, automatic grinding equipment has not been popularized, and relevant research and technology development are very few. According to the conventional method, it is necessary to separately edit the grinding operation execution program for each ship structural component. Since the edges of ship components are divided into welded edges and free edges, the filleting operation only needs to be performed on the free edges, so it is necessary to discriminate them. Due to the characteristics of multiple varieties and variable batches of ship components, one type of workpiece corresponds to one grinding control instruction, resulting in a large amount of manual programming work and possible errors, and the intelligence level of grinding equipment is relatively low.

[0004] Taking a typical ship component model as an example, as Figure 1 shown, after manual discrimination, as Figure 1 shown;

[0005] First, the green lines are the free edges that need to be ground;

[0006] Second, the red lines are non-free edges, i.e., the edges to be welded;

[0007] Third, the cyan lines are the scribing marks for stiffener positioning;

[0008] Fourth, the black lines are the idle travel trajectories of the cutting machine.

[0009] It can be seen that there are many lines in the model, and it is time-consuming and laborious to manually select and mark the free edges, and errors are likely to occur.

[0010] To solve this problem, it is urgent to develop a method for discriminating free edges of ship components and generating grinding control instructions. Summary of the Invention

[0011] Aiming at the problems existing in the prior art, the present invention provides a method for discriminating free edges of ship components and generating grinding control instructions. After using this method for discriminating free edges of ship components and generating grinding control instructions, based on the geometric model file of ship components, by analyzing and summarizing the characteristics of free edges of ship components, according to the mutual relationship of adjacent edges, it is determined whether it is a free edge. Combining the start and end point coordinates of the free edge of the edge, using a programming language, the generation of automatic edge grinding control instructions is realized, achieving the effects of saving manpower, reducing working hours, and reducing the error rate of manual programming, greatly reducing the workload of manual programming, further improving the intelligence level of grinding equipment, and being able to plan the grinding sequence between each group of free edges according to the position distribution of each group of line segments, reducing the idle stroke movement distance of the grinding equipment, improving the operation efficiency, and slowing down the daily movement wear of the grinding equipment.

[0012] To solve the above technical problems, the technical solution adopted by the present invention is:

[0013] Provide a method for discriminating free edges of ship components and generating grinding control instructions, and the method for discriminating free edges of ship components and generating grinding control instructions includes steps;

[0014] S1: According to the common characteristic that free edges all contain arc lines, a first-round discrimination is carried out to eliminate the cutting lead arcs with smaller radii and the arc-shaped outer edges with larger radii in the ship component model, and the arc free edges are screened out;

[0015] S2: On the basis of discriminating the arc free edges, a second-round discrimination is carried out to eliminate the component edge lines that are not connected or connected but not tangent to the arc free edges, and the straight free edges are screened out;

[0016] S3: Based on the screening of arc free edges and straight free edges in the ship component model, the free edge coordinate data is obtained at the same time. Based on the line segment type, coordinate data, and mutual relationship of line segments, with the help of the ship component free edge grinding equipment, line segment grouping, grinding motion trajectory planning, and automatic generation of free edge grinding control instructions are carried out.

[0017] The further technical solution adopted by the present invention to solve its technical problems is:

[0018] Further, in S1, the discrimination steps for screening out the arc free edges include:

[0019] S11: Extract the characteristic value of a line from the ship component model and judge whether the line is an arc line; when the line is judged to be an arc line, then continue to judge whether the radius of the arc line is less than the set minimum radius; otherwise, the line is judged to be a straight line;

[0020] S12: If the radius of the arc line is less than the set minimum radius value, the line is determined to be a cutting lead arc; otherwise, proceed to determine whether the radius of the arc line is greater than the set maximum radius value.

[0021] S13: If the radius of the arc line is greater than the set maximum radius value, the arc line is the edge line of the component; otherwise, the arc line is determined to be an arc free edge.

[0022] Furthermore, the characteristic information of the arc line includes the line segment type, arc radius, starting point coordinates, center coordinates, and ending point coordinates; the characteristic information of the straight line includes the line segment type, starting point coordinates, and ending point coordinates.

[0023] Furthermore, in S2, the discrimination steps for screening out the straight free edge include:

[0024] S21: Extract the characteristic values of a line from the ship component model and determine whether the line is an arc line; if the line is not an arc line, the line is determined to be a straight line.

[0025] S22: Determine whether the straight line is connected to the arc free edge. When the straight line is connected to the arc free edge, continue to determine whether the connection relationship between the straight line and the arc free edge is tangent; otherwise, the straight line is the edge line of the component.

[0026] S23: When the connection relationship between the straight line and the arc free edge is determined to be tangent, the straight line is determined to be a straight free edge; otherwise, the straight line is the edge line of the component.

[0027] Furthermore, in S3, the steps for performing line segment grouping include: According to the mutual relationship of the identified multiple line segments, divide the line segments connected to each other into several groups. The line segments within each group are connected end to end, and the line segments between two groups are independent of each other.

[0028] Furthermore, in S3, the steps for planning the grinding motion trajectory include:

[0029] S31: Plan the grinding sequence of each group of line segments according to the position distribution of each group of line segments.

[0030] S32: According to the line segment grouping situation, the multi-segment set formed by each group of free edges constitutes a closed curve or an open curve.

[0031] Furthermore, in S31, when the multi-segment set formed by each group of free edges constitutes a closed curve, starting from the endpoint of any arc free edge, move clockwise point by point back to the starting point. The feed point is selected at a position with a safe distance along the radius direction from the endpoint of the initial arc free edge, and the retract point is selected at the same point as the feed point.

[0032] Further, in S32, when the polyline set formed by each group of free edges constitutes an open curve, starting from the midpoint, first trace counterclockwise to the starting point of the free edge set of this group, then return to the midpoint, and move clockwise to the end point. The selection of the midpoint and its tool approach point refers to the closed curve scheme, and the tool retraction points at both ends are selected at positions with a safe distance along the extended direction of the end point movement.

[0033] Further, based on the position coordinates of the component edge endpoints in the grinding motion trajectory planning, the position coordinates of the auxiliary points are calculated, and combined with the common instructions in numerical control programming, the free edge grinding control instructions are automatically generated.

[0034] Further, the free edge grinding control instructions include linear motion G01, clockwise motion G02, counterclockwise motion G03, clockwise tool compensation cancellation G40 at the tool retraction point, left tool compensation activation G41 at the counterclockwise tool approach point, right tool compensation activation G42 at the clockwise tool approach point, tool compensation cancellation G40 at the counterclockwise tool approach point, and setting the grinding linear velocity F.

[0035] The beneficial effects of the present invention are as follows:

[0036] First, according to the common characteristic that each free edge contains arc lines, the present invention conducts the first round of discrimination, eliminates the cutting lead arcs with smaller radii and the arc-shaped outer edges with larger radii in the ship component model, and screens out the arc free edges. Then, based on the identified arc free edges, the second round of discrimination is carried out to eliminate the component edge lines that are not connected or connected but not tangent to the arc free edges, and screen out the straight free edges. Finally, based on the screening of the arc free edges and straight free edges in the ship component model, the free edge coordinate data is obtained at the same time. Based on the line segment type, coordinate data, and mutual relationship of the line segments, with the help of the ship component free edge grinding equipment, line segment grouping, grinding motion trajectory planning, and automatic generation of free edge grinding control instructions are performed. Based on the geometric model file of the ship component, by analyzing and summarizing the characteristics of the free edges of the ship component, according to the mutual relationship of adjacent edges, it is determined whether it is a free edge. Combining the start and end point coordinates of the free edge of the edge, using programming language, the generation of automatic edge grinding control instructions is realized, achieving the effects of saving manpower, reducing working hours, and reducing the error rate of manual programming, greatly reducing the workload of manual programming, further improving the intelligence level of the grinding equipment, and using the method of the present invention can plan the grinding sequence between each group of free edges according to the position distribution of each group of line segments, reduce the idle stroke movement distance of the grinding equipment, improve the operation efficiency, and slow down the daily movement wear of the grinding equipment.

[0037] The above description is only an overview of the technical solution of the present invention. In order to be able to understand the technical means of the present invention more clearly and implement it according to the content of the specification, the following takes the preferred embodiments of the present invention and combines with the drawings to describe in detail as follows. Description of the Drawings

[0038] Figure 1 It is a schematic diagram of a typical ship component model;

[0039] Figure 2 It is a schematic flow chart of a method for discriminating free edges of ship components and generating grinding control instructions described in an embodiment of the present invention;

[0040] Figure 3 It is a schematic flow chart of the discrimination process for screening out circular arc free edges described in an embodiment of the present invention;

[0041] Figure 4 It is a schematic flow chart of the discrimination process for screening out straight-line free edges described in an embodiment of the present invention;

[0042] Figure 5 It is a schematic diagram of line segment grouping described in an embodiment of the present invention;

[0043] Figure 6 It is a schematic diagram of a closed curve described in an embodiment of the present invention;

[0044] Figure 7 It is a schematic diagram of an open curve described in an embodiment of the present invention. Detailed implementation manners

[0045] The following specific embodiments illustrate the specific implementation manners of the present invention. Those skilled in the art can easily understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented in other different ways, that is, without departing from the scope disclosed by the present invention, it can be subject to different modifications and changes.

[0046] A method for discriminating free edges of ship components and generating grinding control instructions, as Figure 2 shown, the method for discriminating free edges of ship components and generating grinding control instructions includes steps;

[0047] The first step: Based on the common characteristic that free edges all contain circular arc lines, perform the first-round discrimination, eliminate the cutting lead arcs with relatively small radii and the arc-shaped outer edges with relatively large radii in the ship component model, and screen out the circular arc free edges;

[0048] The second step: On the basis of discriminating the circular arc free edges, perform the second-round discrimination, eliminate the component edge lines that are not connected or connected but not tangent to the circular arc free edges, and screen out the straight-line free edges;

[0049] The third step: Based on the screening of the circular arc free edges and straight-line free edges in the ship component model, obtain the free edge coordinate data at the same time. Based on the line segment type, coordinate data, and the mutual relationship of line segments, with the help of the ship component free edge grinding equipment, perform line segment grouping, grinding motion trajectory planning, and automatically generate free edge grinding control instructions.

[0050] Example 1:

[0051] The discriminant steps for screening out the free edges of arcs are as follows Figure 3 shown, including:

[0052] S11: Extract the eigenvalue of a line from the ship component model, and determine whether the line is an arc line; when the line is determined to be an arc line, then continue to determine whether the radius of the arc line is less than the set minimum radius value; otherwise, the line is determined to be a straight line;

[0053] S12: When it is determined that the radius of the arc line is less than the set minimum radius value, then the line is determined to be a cutting arc starting; otherwise, proceed to determine whether the radius of the arc line is greater than the set maximum radius value;

[0054] S13: When it is determined that the radius of the arc line is greater than the set maximum radius value, then the arc line is the component edge line; otherwise, the arc line is determined to be a free edge of the arc.

[0055] The characteristic information of the arc line includes the line segment type, arc radius, starting point coordinates, center coordinates, and ending point coordinates.

[0056] Example 2:

[0057] The discriminant steps for screening out the free edges of straight lines are as follows Figure 4 shown, including:

[0058] S21: Extract the eigenvalue of a line from the ship component model, and determine whether the line is an arc line; when the line is not an arc line, then the line is determined to be a straight line;

[0059] S22: Determine whether the straight line is connected to the free edge of the arc. When the straight line is connected to the free edge of the arc, then continue to determine whether the connection relationship between the straight line and the free edge of the arc is tangent; otherwise, the straight line is the component edge line;

[0060] S23: When it is determined that the connection relationship between the straight line and the free edge of the arc is tangent, then the straight line is determined to be a free edge of the straight line; otherwise, the straight line is the component edge line.

[0061] The characteristic information of the straight line includes the line segment type, starting point coordinates, and ending point coordinates.

[0062] Example 3:

[0063] The steps for performing line segment grouping include: according to the mutual relationship of the identified multiple line segments, divide the line segments connected to each other into several groups, where the line segments within each group are connected end to end, and the line segments between two groups are independent of each other, as Figure 5 shown.

[0064] The steps for planning the grinding motion trajectory include:

[0065] S31: Plan the grinding sequence for each group of line segments according to the position distribution of each group of line segments.

[0066] S32: According to the line segment grouping situation, the multi-segment set formed by each group of free edges constitutes a closed curve or an open curve.

[0067] In S31, when the multi-segment set formed by each group of free edges constitutes a closed curve, as Figure 6 shown, starting from the end point of any arc free edge, move point by point clockwise back to the starting point, select the feed point at the position of the safe distance along the radial direction from the end point of the initial arc free edge, and select the same point as the feed point for the retraction point.

[0068] In S32, when the multi-segment set formed by each group of free edges constitutes an open curve, as Figure 7 shown, starting from the midpoint, first trace back counterclockwise to the starting point of the free edge set of this group, then return to the midpoint, and move clockwise to the end point. The selection of the midpoint and its feed point refers to the closed curve scheme, and the retraction points at both ends are selected at the positions of the safe distance along the extended direction of the movement of the end points.

[0069] Based on the position coordinates of the component edge end points in the above-mentioned grinding motion trajectory planning, calculate the position coordinates of the auxiliary points, and combine with the commonly used instructions in numerical control programming to automatically generate the free edge grinding control instructions.

[0070] The free edge grinding control instructions include linear motion G01, clockwise motion G02, counterclockwise motion G03, clockwise retraction point to cancel tool compensation G40, counterclockwise feed point to enable left tool compensation G41, clockwise feed point to enable right tool compensation G42, counterclockwise feed point to cancel tool compensation G40, and set the grinding linear speed F.

[0071] The above are only embodiments of the present invention, and thus do not limit the patent scope of the present invention. Any equivalent structures made by using the content of the specification and drawings of the present invention, directly or indirectly applied in other related technical fields, are similarly included in the patent protection scope of the present invention.

Claims

1. A method for discriminating free edges of ship components and generating grinding control instructions, characterized in that: The method for discriminating free edges of ship components and generating grinding control instructions includes the following steps; S1: According to the common feature that free edges all contain arc lines, conduct the first-round discrimination, eliminate the cutting lead arcs with relatively small radii and the arc-shaped outer edges with relatively large radii in the ship component model, and screen out the arc free edges; S2: On the basis of discriminating the arc free edges, conduct the second-round discrimination, eliminate the component edge lines that are not connected or connected but not tangent to the arc free edges, and screen out the straight free edges; S3: Based on the screening of the arc free edges and straight free edges in the ship component model, obtain the free edge coordinate data at the same time. Based on the line segment type, coordinate data, and mutual relationship of line segments, use the ship component free edge grinding equipment to perform line segment grouping, grinding motion trajectory planning, and automatically generate free edge grinding control instructions; In S3, the step of performing line segment grouping includes: According to the mutual relationship of the discriminated multi-segment line segments, divide the line segments connected to each other into several groups. The line segments within each group are connected end to end, and the line segments between two groups are independent of each other; In S3, the step of grinding motion trajectory planning includes: S31: According to the position distribution of each group of line segments, plan the grinding sequence of each group of line segments; S32: According to the line segment grouping situation, the multi-segment set formed by each group of free edges constitutes a closed curve or an open curve; Based on the position coordinates of the component edge end points in the grinding motion trajectory planning, calculate the position coordinates of the auxiliary points, and combine the commonly used instructions in numerical control programming to automatically generate free edge grinding control instructions.

2. The method for discriminating free edges of ship components and generating grinding control instructions according to claim 1, characterized in that: In S1, the discrimination step of screening out the arc free edges includes: S11: Extract the characteristic value of a line from the ship component model and judge whether the line is an arc line; when the line is judged to be an arc line, then continue to judge whether the radius of the arc line is less than the set minimum radius value; otherwise, the line is judged to be a straight line; S12: When it is judged that the radius of the arc line is less than the set minimum radius value, the line is judged to be a cutting lead arc; otherwise, enter the judgment of whether the radius of the arc line is greater than the set maximum radius value; S13: When it is judged that the radius of the arc line is greater than the set maximum radius value, the arc line is the component edge line; otherwise, the arc line is judged to be an arc free edge.

3. The method for discriminating free edges of ship components and generating grinding control instructions according to claim 2, characterized in that: The characteristic information of the arc line includes line segment type, arc radius, starting point coordinates, center coordinates, and ending point coordinates; the characteristic information of the straight line includes line segment type, starting point coordinates, and ending point coordinates.

4. The method for discriminating free edges of ship components and generating grinding control instructions according to claim 1, characterized in that: In S2, the discrimination step of screening out the straight free edges includes: S21: Extract the eigenvalue of a line from the ship component model and determine whether the line is an arc line; if the line is not an arc line, the line is determined to be a straight line. S22: Determine whether the straight line is connected to the free edge of the arc. When the straight line is connected to the free edge of the arc, continue to determine whether the connection relationship between the straight line and the free edge of the arc is tangency; otherwise, the straight line is the edge line of the component. S23: When it is determined that the connection relationship between the straight line and the free edge of the arc is tangency, the straight line is determined to be the free edge of the straight line; otherwise, the straight line is the edge line of the component.

5. A method for generating a discrimination and grinding control instruction for the free edge of a ship component according to claim 1, wherein: In S32, when the polyline set formed by each group of free edges constitutes a closed curve, starting from the endpoint of any free edge of the arc, move clockwise point by point back to the starting point, and select the feed point at a position with a safe distance along the radial direction from the endpoint of the initial free edge of the arc. The retract point is selected at the same point as the feed point.

6. A method for generating a discrimination and grinding control instruction for the free edge of a ship component according to claim 1, wherein: In S32, when the polyline set formed by each group of free edges constitutes an open curve, starting from the midpoint, first trace back counterclockwise to the starting point of the free edge set of this group, then return to the midpoint, and move clockwise to the end point. The selection of the midpoint and its feed point refers to the closed curve scheme, and the retract points at both ends are selected at positions with a safe distance along the extended direction of the end point movement.

7. A method for generating a discrimination and grinding control instruction for the free edge of a ship component according to claim 1, wherein: The free edge grinding control instruction includes linear motion G01, clockwise motion G02, counterclockwise motion G03, clockwise retract point to cancel tool compensation G40, counterclockwise feed point to activate tool left compensation G41, clockwise feed point to activate tool right compensation G42, counterclockwise feed point to cancel tool compensation G40, and set the grinding linear velocity F.

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