CN110658783A - Solving method and system for feasible region of five-axis machining cutter shaft - Google Patents
Solving method and system for feasible region of five-axis machining cutter shaft Download PDFInfo
- Publication number
- CN110658783A CN110658783A CN201910902859.4A CN201910902859A CN110658783A CN 110658783 A CN110658783 A CN 110658783A CN 201910902859 A CN201910902859 A CN 201910902859A CN 110658783 A CN110658783 A CN 110658783A
- Authority
- CN
- China
- Prior art keywords
- cutter shaft
- boundary
- feasible region
- feasible
- cutter
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/18—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form
- G05B19/408—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by data handling or data format, e.g. reading, buffering or conversion of data
- G05B19/4086—Coordinate conversions; Other special calculations
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/30—Nc systems
- G05B2219/35—Nc in input of data, input till input file format
- G05B2219/35356—Data handling
Landscapes
- Engineering & Computer Science (AREA)
- Human Computer Interaction (AREA)
- Manufacturing & Machinery (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Automation & Control Theory (AREA)
- Numerical Control (AREA)
Abstract
The invention discloses a method and a system for solving the feasible region of a five-axis machining cutter shaft, belonging to the field of numerical control machining, wherein the method comprises the following steps: taking the binary image of the cutter shaft feasible region of the previous cutter contact as the initial cutter shaft feasible region of the current cutter contact, and solving the boundary of the initial cutter shaft feasible region; performing collision detection on the cutter shaft directions in the boundary, setting all pixels corresponding to infeasible cutter shaft directions as 0, updating the initial cutter shaft feasible region, and continuously searching the boundary of the new cutter shaft feasible region until all the cutter shaft directions in the boundary are the feasible cutter shaft directions without collision; and expanding the boundary of the finally updated target cutter shaft feasible region outwards for a circle, subtracting the expanded cutter shaft feasible region to obtain an expanded boundary, performing collision detection on the expanded boundary, adding the feasible cutter shaft direction into the target cutter shaft feasible region, and repeating the operations until all the feasible cutter shaft directions are infeasible. The invention can greatly reduce the calculation amount and improve the calculation efficiency.
Description
Technical Field
The invention belongs to the field of numerical control machining, and particularly relates to a method and a system for solving a feasible region of a five-axis machining cutter shaft.
Background
Compared with three-axis machining, five-axis machining is provided with two rotating shafts, and planning of the cutter shaft direction is very important in the five-axis machining. The planning of the cutter shaft direction needs to consider the interference problem in the processing from the geometric angle and the process performance constraint problem from the processing process angle. In five-axis numerical control machining, the cutter shaft direction is limited in a feasible region under the constraint of the machining process, so that the interference and collision phenomena can be avoided in the machining process, and the machining process requirements can be met.
At present, the collision detection method for traversing all discrete cutter shaft directions is mainly adopted for solving the cutter shaft feasible region, but the method has complex solving process for solving the cutter shaft feasible region, large calculation amount and long consumed time.
Disclosure of Invention
Aiming at the defects or improvement requirements in the prior art, the invention provides a method and a system for solving the feasible region of the five-axis machining cutter shaft, so that the technical problems of complex solving process, large calculation amount and long time consumption in the conventional feasible region solving in the cutter shaft direction are solved.
To achieve the above object, according to an aspect of the present invention, there is provided a method for solving a feasible domain of a five-axis machining tool axis, including:
(1) acquiring a cutter shaft feasible region of a previous cutter contact point, converting the cutter shaft feasible region into a binary image, taking the binary image as an initial cutter shaft feasible region of a current cutter contact point, and solving the boundary of the initial cutter shaft feasible region of the current cutter contact point;
(2) performing collision detection on the cutter shaft directions in the boundary, if no collision occurs, executing the step (3), if the collided cutter shaft directions occur, setting all pixel points corresponding to infeasible cutter shaft directions as 0, updating the initial cutter shaft feasible region to obtain a new cutter shaft feasible region, and continuously searching the boundary of the new cutter shaft feasible region until all the cutter shaft directions in the boundary are the unfeasible cutter shaft directions without collision;
(3) and (3) outwards expanding the boundary of the finally updated target cutter shaft feasible region for a circle, subtracting the expanded target cutter shaft feasible region to obtain an expanded boundary, performing collision detection on the expanded boundary, finishing the boundary expansion process if all the target cutter shaft feasible regions are infeasible cutter shaft directions, adding the feasible cutter shaft directions into the target cutter shaft feasible region if the feasible cutter shaft directions exist, and repeating the step (3) until all the target cutter shaft directions are infeasible cutter shaft directions after updating.
Preferably, the arbor feasible region is such as to satisfy T.np＞cosθcAnd T.fp＞cosθcTwo constraint conditions, and no interference collision, wherein T represents the cutter shaft direction, npRepresenting the normal vector of the curved surface at the point of contact P of the knife, fpDenotes the feed direction at P, θcIndicating the cutter axis direction T and the curved surface normal direction npOr the size of the included angle between the cutter shaft direction T and the feeding direction fpThe size of the included angle.
Preferably, step (1) comprises:
and obtaining the cutter shaft feasible region of the previous cutter contact point and converting the cutter shaft feasible region into a binary image, taking the binary image as the initial cutter shaft feasible region of the current cutter contact point, and finding the boundary of the initial cutter shaft feasible region by using a boundary search findContours function in OpenCV.
Preferably, step (2) comprises:
(2.1) according to the coordinates of the current cutter position point, the normal vector of the curved surface and the feeding direction, performing collision detection on the cutter shaft direction in the boundary of the feasible region of the initial cutter shaft, reserving the feasible cutter shaft direction, setting all pixels corresponding to the infeasible cutter shaft direction as 0, and marking the cutter shaft direction which has undergone collision detection in a target array, wherein the size of the target array is the same as that of the feasible region of the initial cutter shaft;
and (2.2) updating the initial cutter shaft feasible region according to the collision detection result in the step (2.1) to obtain a new cutter shaft feasible region, obtaining the boundary of the new cutter shaft feasible region, and repeatedly executing the step (2.1) based on the boundary of the new cutter shaft feasible region until all collision detection results indicate that all boundary cutter shaft directions are feasible.
Preferably, step (3) comprises:
(3.1) expanding outwards for one circle along the boundary of the feasible region of the target cutter shaft after final updating by using a dilate function, and then subtracting the feasible region of the target cutter shaft before expansion by using an addWeighted function to obtain an expanded boundary;
(3.2) performing collision detection on the cutter shaft direction in the expanded boundary, adding the cutter shaft direction which does not collide to the target cutter shaft feasible region to obtain an updated target cutter shaft feasible region, and marking the cutter shaft direction which has undergone collision detection in the target array;
(3.3) obtaining the expansion boundary of the updated target cutter shaft feasible region, and returning to execute the step (3.2) based on the expansion boundary of the updated target cutter shaft feasible region until all results of cutter shaft direction collision detection in the expansion boundary are infeasible.
To achieve the above object, according to another aspect of the present invention, there is provided a system for solving a five-axis machining tool axis feasible region, including:
the initial boundary calculation module is used for acquiring the cutter shaft feasible region of the previous cutter contact and converting the cutter shaft feasible region into a binary image, taking the binary image as the initial cutter shaft feasible region of the current cutter contact, and calculating the boundary of the initial cutter shaft feasible region of the current cutter contact;
the boundary contraction module is used for performing collision detection on the cutter shaft directions in the boundary, setting all pixels corresponding to infeasible cutter shaft directions as 0 if the collided cutter shaft directions appear, updating the initial cutter shaft feasible region to obtain a new cutter shaft feasible region, and continuously searching the boundary of the new cutter shaft feasible region until all the cutter shaft directions in the boundary are the feasible cutter shaft directions without collision;
and the boundary expansion module is used for expanding a circle outwards along the boundary of the finally updated target cutter shaft feasible region, subtracting the expanded target cutter shaft feasible region to obtain an expanded boundary, performing collision detection on the expanded boundary, finishing the boundary expansion process if all the cutter shaft directions are infeasible, adding the feasible cutter shaft directions into the target cutter shaft feasible region if the feasible cutter shaft directions exist, and repeatedly executing the operation of the boundary expansion module after updating until all the cutter shaft directions are infeasible.
Preferably, the arbor feasible region is such as to satisfy T.np＞cosθcAnd T.fp＞cosθcTwo constraint conditions, and no interference collision, wherein T represents the cutter shaft direction, npRepresenting the normal vector of the curved surface at the point of contact P of the knife, fpDenotes the feed direction at P, θcIndicating the cutter axis direction T and the curved surface normal direction npOr the size of the included angle between the cutter shaft direction T and the feeding direction fpThe size of the included angle.
Preferably, the initial boundary obtaining module is specifically configured to obtain a tool axis feasible region of a previous tool contact and convert the tool axis feasible region into a binary image, use the binary image as an initial tool axis feasible region of a current tool contact, and obtain a boundary of the initial tool axis feasible region by using a boundary search findContours function in OpenCV.
Preferably, the boundary contracting module includes:
the first collision detection module is used for performing collision detection on the cutter shaft direction in the boundary of the feasible region of the initial cutter shaft according to the coordinate of the current cutter position point, the normal vector of the curved surface and the feeding direction, reserving the feasible cutter shaft direction, setting all pixels corresponding to the infeasible cutter shaft direction as 0, and marking the cutter shaft direction which is subjected to collision detection in a target array, wherein the size of the target array is the same as that of the feasible region of the initial cutter shaft;
and the boundary contraction submodule is used for updating the initial cutter shaft feasible region to obtain a new cutter shaft feasible region according to the collision detection result in the first collision detection module, acquiring the boundary of the new cutter shaft feasible region, and repeatedly executing the operation of the first collision detection module based on the boundary of the new cutter shaft feasible region until all collision detection results are that all boundary cutter shaft directions are feasible.
Preferably, the boundary expansion module includes:
the extended boundary solving module is used for extending outwards for a circle along the boundary of the finally updated target cutter shaft feasible region by using a dilate function, and then subtracting the target cutter shaft feasible region before extension by using an addWeighted function to obtain an extended boundary;
the second collision detection module is used for performing collision detection on the cutter shaft direction in the expanded boundary, adding the cutter shaft direction which does not collide to the target cutter shaft feasible region to obtain an updated target cutter shaft feasible region, and marking the cutter shaft direction which is subjected to collision detection in the target array;
and the boundary expansion submodule is used for solving the expansion boundary of the updated target cutter shaft feasible region, and returning to execute the operation of the second collision detection module based on the expansion boundary of the updated target cutter shaft feasible region until all cutter shaft direction collision detection results in the expansion boundary are infeasible.
In general, compared with the prior art, the above technical solution contemplated by the present invention can achieve the following beneficial effects: the invention defines the representation method and constraint conditions of the cutter shaft feasible region, considers the constraint of the process of the cutter shaft direction and the interference collision, and on the basis, combines the image processing technology to update the boundary of the cutter shaft direction feasible region, aims to reduce the number of the cutter shaft directions needing to be detected when solving the cutter shaft feasible region, greatly reduces the calculated amount and improves the calculation efficiency compared with the common collision detection method needing to traverse all discrete cutter shaft directions.
Drawings
Fig. 1 is a schematic view of a knife axis direction at a knife contact point according to an embodiment of the present invention;
fig. 2 is a first constraint and a second constraint of a feasible region of a cutter shaft, wherein (a) is the first constraint and (b) is the second constraint;
FIG. 3 is a schematic view of a tool-axis Gaussian sphere in a workpiece coordinate system according to an embodiment of the present invention;
FIG. 4 is a representation of an arbor feasible region (F-Map) in plan view according to an embodiment of the present invention;
FIG. 5 is an F-map of a blade contact provided by an embodiment of the present invention;
FIG. 6 is a F-Map comparison of adjacent blade contacts provided by embodiments of the present invention;
fig. 7 is a flowchart of a method for solving a feasible region of a five-axis machining cutter shaft according to an embodiment of the present invention;
FIG. 8 illustrates an initial F-map and its boundaries provided by an embodiment of the present invention;
FIG. 9 is a schematic diagram of a boundary contraction process of an F-Map according to an embodiment of the present invention;
FIG. 10 is a comparison of the final results of a boundary contraction provided by embodiments of the present invention;
FIG. 11 is an expanded boundary image provided by embodiments of the present invention;
FIG. 12 is a schematic diagram of a boundary dilation process for an F-Map according to an embodiment of the present invention;
FIG. 13 is a schematic diagram of the final F-map after boundary dilation according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
The invention provides a method and a system for solving an optimized cutter shaft feasible region, which are combined with an image processing technology to update the boundary of the cutter shaft feasible region, thereby greatly reducing the calculation amount and improving the calculation efficiency compared with the common collision detection method which needs to traverse all discrete cutter shaft directions.
Firstly, a representation method and constraint conditions of the feasible region of the cutter shaft, and a solving method of the feasible region of the cutter shaft (F-Map) of a single cutter contact based on Opcode collision detection under the constraint are introduced.
As shown in fig. 1, on the workpiece seatMarker system XW-YW-ZWWhere v is a portion of a free-form surface to be machined, P is a tool contact point on the tool path, kp-fp-npIs a local coordinate system at P, where npIs the normal vector of the curved surface at P, fpIs the feed direction at P, kpIs npAnd fpA vector product of (1), TLIs the arbor direction at point P, PLCC curve represents the curve of the contact point of the cutter as the position of the center point of the ball-point cutterLRepresenting the arbor vectors T and npAngle of direction, betaLRepresents kp-fpProjection of a surface and kpThe included angle of the direction.
Considering the accessibility of the tool and the process requirements in machining, two constraints on the tool axis direction need to be imposed in the local coordinate system.
As shown in FIG. 2, kp-fp-npFor the local coordinate system at the tool contact point P, a unit sphere with P as the sphere center and radius of 1 is defined, which is called a gaussian sphere, and the tool axis direction can be represented by a vector from the gaussian sphere center to a point on the spherical surface. As shown in FIG. 2(a), constraint one is tool accessibility, and the arbor vector is constrained to be within half a Gaussian sphere above the tangent plane at P, i.e., T.npIf is more than 0, T represents a cutter axis vector; as shown in fig. 2(b), the constraint two considers the problem of the processing technology, and further constrains the cutter axis vector in a quarter-gauss sphere, T · fpIs greater than 0. In order to avoid the extreme angle, it is not enough that the angle between the knife axis and the normal vector of the curved surface and the feeding direction is only an acute angle, and it is further limited to 5 to 85 degrees, and it is preferable to define the angle θc＝85°，
Wherein, thetacIndicating the cutter axis direction T and the curved surface normal direction npOr the size of the included angle between the cutter shaft direction T and the feeding direction fpThe size of the included angle of (a) is as follows:
T·np＞cosθc T·fp＞cosθc
then, the constraint in the local coordinate system is converted into the workpiece coordinate system, and as shown in fig. 3, the gaussians are unified into the coordinate source of the workpiece coordinate systemAt this point, the unit vector T indicates only the arbor direction without indicating the position, and then, the forward inclination angle α and the roll inclination angle β in the arbor direction are denoted by T ═ (sin α cos β, sin α sin β, cos α), and α is T and the coordinate axis Z of the workpiece coordinate system, as in fig. 1WBeta is T at XW-YWProjection and X on a planeWThe included angle of (a). The feasible region of the cutter shaft is a cutter shaft direction collection which meets two constraint conditions under the local coordinate system and does not generate interference collision, and can correspond to a region of a Gaussian sphere, namely F-Map.
And T can be uniquely represented by α and β, so that a three-dimensional gaussian sphere is mapped into a two-dimensional α - β domain, and α and β are uniformly divided into 90 × 180 grids every two degrees in (0 °, 180 °) and (0 °, 360 °), respectively, and each grid point represents one arbor direction, as shown in fig. 4.
For the F-Map calculation method of a single tool contact, all grid points of an alpha-beta plane are traversed in sequence, and whether constraint one is met is judged firstly: t.np＞cosθcAnd constraint two: t.fp＞cosθcAnd then collision detection is carried out on the cutter shaft directions in the area one by using an Opcode collision detection library, and finally all the cutter shaft directions which do not collide are the feasible region F-Map of the cutter shaft.
As shown in fig. 5, the F-map is the F-map that is obtained at a certain knife contact, but the number of collision detections in the one-by-one traversal method is too many, and the calculation amount is large, so that the time is consumed.
The method is mainly based on the similarity of space environments between adjacent knife contacts, and the comparison shown in figure 6 shows that the knife shaft feasible region images of the adjacent knife contacts are very similar, so that the next adjacent point can be calculated by considering the knife shaft feasible region of the previous knife contact.
Selecting a contact point, using the obtained F-map, and then using a boundary updating method to obtain the F-map of the next adjacent contact point, wherein the general flow chart is shown in FIG. 7, and the specific process is as follows:
step 1: F-Map for acquiring previous contacti-1Converting the current tool contact into a Mat type binary image serving as an initial F-map of the current tool contact, and solving an initial F-map boundary;
step 2: collision detection is carried out on the cutter shaft directions in the boundary, if no collision occurs, the step 3 is directly carried out, if the collision occurs, all infeasible corresponding pixel points of the cutter shaft directions are set to be 0, the boundary is continuously searched after the image is updated, and the cutter shaft directions in the boundary are all the feasible cutter shaft directions without collision;
and step 3: and (3) performing expansion processing on the image updated in the step (2) to obtain an expanded boundary of the image, then performing collision detection on the expanded boundary, finishing updating the boundary if the image is in all infeasible cutter shaft directions, adding the image into the F-map if the image is in the infeasible cutter shaft directions, and repeating the step (3) until the image is in all infeasible cutter shaft directions after updating.
As shown in FIG. 8, the binary image of the F-Map of the previous knife-edge point is the initial image, and the boundary search in OpenCV is first used: the findContours function finds the knife-axis feasible region boundary BFM (boundary of F-Map), and then the boundary contraction process and the boundary expansion process are sequentially performed.
a) And (3) boundary contraction process:
and (3) according to the coordinates, the curved surface normal vector and the feeding direction of the current tool location point, performing collision detection on the tool axis direction of the boundary obtained in the step (1), judging whether the tool axis direction is a feasible tool axis direction, if so, reserving the tool axis direction, and otherwise, removing the tool axis direction (setting the tool axis direction as 0). And updating the collision detection result of the current knife location point on the BFM of the previous knife location point, thereby obtaining the first updated F-Map. If the detection result in the step 2 has the infeasible arbor direction, the unfeasible arbor direction may exist inside the F-Map boundary in the step 1, so the boundary needs to be shrunk. And (3) repeating the step (2), namely continuously solving the boundary of the new F-Map obtained in the step (2), then carrying out collision detection on the boundary cutter shaft direction, then repeating the previous process, removing the infeasible cutter shaft direction, reserving the feasible cutter shaft direction, and updating the F-Map again. And (4) circulating the process until all the extracted collision detection results of all the cutter shaft directions of the new F-Map boundary are feasible cutter shaft directions.
Taking a part (oval part) of the F-Map in fig. 8 as an example for detailed description, as shown in fig. 9, (a) is an initial F-Map and a boundary, then according to the coordinates of the current tool location point, the normal vector of the curved surface and the feed direction, performing collision detection on the tool axis direction in the boundary, and determining whether the tool axis direction is a feasible tool axis direction, if so, retaining, otherwise, removing (setting to 0), as shown in (b). Meanwhile, a check array with the same size as the F-map (for example, 90 x 180) is created for storing the cutter shaft direction subjected to collision detection. Firstly, initializing the array to be 0, setting the value of the corresponding position of the cutter shaft direction in the array to be 1 every time collision detection is carried out, and in the subsequent detection, if the value of the corresponding position of a certain cutter shaft direction in the array is 1, the detection is already carried out, the detection is not required, the times of collision detection can be reduced, and the calculation time is saved.
Then, as shown in (c), the collision detection result is updated to the F-Map, and a new boundary BFM is acquired again (boundary of F-Map). Since the F-Map is updated, the collision detection process from (a) to (b) needs to be performed again until all the boundary cutter shaft directions are feasible as a result of all the collision detection, that is, the F-Map is not updated, as shown in (d), otherwise, the flow in the dashed line box in fig. 9 needs to be circulated, and the check array needs to be updated and maintained each time until all the boundary cutter shaft directions are shown in (d), and the F-Map does not need to be updated as well as the collision cutter shaft directions in the BFM do not occur.
The result of the final boundary contraction is shown in FIG. 10 in comparison to the original F-map.
b) And (3) boundary expansion process:
if a feasible arbor direction exists in the BFM during the boundary contraction process, which indicates that a feasible arbor direction may also exist outside the boundary of the F-Map, the F-Map needs to be expanded, and the updated F-Map in fig. 10 is expanded outward by one turn to obtain an outer boundary arbor direction (OBFM), as shown in fig. 11. And then, performing collision detection on the cutter shaft direction (firstly, judging whether the cutter shaft direction is detected in the two-dimensional array, and updating the detected cutter shaft direction in the two-dimensional array), and updating the F-Map after the collision detection is completed. The boundary expanding method comprises the following steps: the expansion boundary of the image can be obtained by firstly expanding the original image by using a scale function and then subtracting the original image by using an addWeighted function.
Similarly, as shown in fig. 12(a), a part (an elliptical part) in fig. 11 is enlarged and described in detail, collision detection is performed on the arbor direction in the expansion boundary OBFM, and if no collision occurs, the arbor direction belongs to a feasible region and is added to the F-Map, and if no collision occurs, the arbor direction is not added, as shown in (b). And (c) after the tool axis direction detection of all expansion boundaries in the OBFM is finished, updating the F-Map and solving the OBFM of the new F-Map, and simultaneously updating the check array as shown in (c).
And (c) repeating the collision detection processes from (a) to (b) on the updated F-Map because the F-Map is updated until all the results of the cutter shaft direction collision detection in the OBFM are infeasible, namely the F-Map is not updated, otherwise, circulating the processes in the broken line frame in the figure 12 until the unfeasible cutter shaft direction shown in (d) is achieved, and the F-Map does not need to be updated.
Thus, the boundary expansion process of the F-Map is finished, the boundary updating process is also finished, and fig. 13 shows the F-Map after the boundary expansion process is finished, that is, the F-Map after the final boundary updating.
The above is an example of a one-time complete F-map boundary updating method.
The detection of all discrete cutter shaft directions by using a general traversal method to solve the F-Map probably needs about 3s, but after the boundary updating algorithm is adopted, the time for calculating the F-Map is about 0.3s, and the time for calculating the F-Map of the cutter position on the cutter path is greatly shortened.
In another embodiment of the present invention, a system for solving a five-axis machining tool axis feasible region is further provided, including:
the initial boundary calculation module is used for acquiring the cutter shaft feasible region of the previous cutter contact and converting the cutter shaft feasible region into a binary image, taking the binary image as the initial cutter shaft feasible region of the current cutter contact, and calculating the boundary of the initial cutter shaft feasible region of the current cutter contact;
the boundary contraction module is used for performing collision detection on the cutter shaft directions in the boundary, setting all pixels corresponding to infeasible cutter shaft directions as 0 if the collided cutter shaft directions appear, updating the initial cutter shaft feasible region to obtain a new cutter shaft feasible region, and continuously searching the boundary of the new cutter shaft feasible region until all the cutter shaft directions in the boundary are the feasible cutter shaft directions without collision;
and the boundary expansion module is used for expanding a circle outwards along the boundary of the finally updated target cutter shaft feasible region, subtracting the expanded target cutter shaft feasible region to obtain an expanded boundary, performing collision detection on the expanded boundary, finishing the boundary expansion process if all the cutter shaft directions are infeasible, adding the feasible cutter shaft directions into the target cutter shaft feasible region if the feasible cutter shaft directions exist, and repeatedly executing the operation of the boundary expansion module after updating until all the cutter shaft directions are infeasible.
The specific implementation of each module may refer to the description in the method embodiment, and the embodiment of the present invention will not be repeated.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (10)
1. A solution method for a feasible region of a five-axis machining cutter shaft is characterized by comprising the following steps:
(1) acquiring a cutter shaft feasible region of a previous cutter contact point, converting the cutter shaft feasible region into a binary image, taking the binary image as an initial cutter shaft feasible region of a current cutter contact point, and solving the boundary of the initial cutter shaft feasible region of the current cutter contact point;
(2) performing collision detection on the cutter shaft directions in the boundary, if no collision occurs, executing the step (3), if the collided cutter shaft directions occur, setting all pixel points corresponding to infeasible cutter shaft directions as 0, updating the initial cutter shaft feasible region to obtain a new cutter shaft feasible region, and continuously searching the boundary of the new cutter shaft feasible region until all the cutter shaft directions in the boundary are the unfeasible cutter shaft directions without collision;
(3) and (3) outwards expanding the boundary of the finally updated target cutter shaft feasible region for a circle, subtracting the expanded target cutter shaft feasible region to obtain an expanded boundary, performing collision detection on the expanded boundary, finishing the boundary expansion process if all the target cutter shaft feasible regions are infeasible cutter shaft directions, adding the feasible cutter shaft directions into the target cutter shaft feasible region if the feasible cutter shaft directions exist, and repeating the step (3) until all the target cutter shaft directions are infeasible cutter shaft directions after updating.
2. The method of claim 1, wherein the arbor runnability field is T-np＞cosθcAnd T.fp＞cosθcTwo constraint conditions, and no interference collision, wherein T represents the cutter shaft direction, npRepresenting the normal vector of the curved surface at the point of contact P of the knife, fpDenotes the feed direction at P, θcIndicating the cutter axis direction T and the curved surface normal direction npOr the size of the included angle between the cutter shaft direction T and the feeding direction fpThe size of the included angle.
3. The method of claim 2, wherein step (1) comprises:
and obtaining the cutter shaft feasible region of the previous cutter contact point and converting the cutter shaft feasible region into a binary image, taking the binary image as the initial cutter shaft feasible region of the current cutter contact point, and finding the boundary of the initial cutter shaft feasible region by using a boundary search findContours function in OpenCV.
4. The method of any one of claims 1 to 3, wherein step (2) comprises:
(2.1) according to the coordinates of the current cutter position point, the normal vector of the curved surface and the feeding direction, performing collision detection on the cutter shaft direction in the boundary of the feasible region of the initial cutter shaft, reserving the feasible cutter shaft direction, setting all pixels corresponding to the infeasible cutter shaft direction as 0, and marking the cutter shaft direction which has undergone collision detection in a target array, wherein the size of the target array is the same as that of the feasible region of the initial cutter shaft;
and (2.2) updating the initial cutter shaft feasible region according to the collision detection result in the step (2.1) to obtain a new cutter shaft feasible region, obtaining the boundary of the new cutter shaft feasible region, and repeatedly executing the step (2.1) based on the boundary of the new cutter shaft feasible region until all collision detection results indicate that all boundary cutter shaft directions are feasible.
5. The method of any one of claims 1 to 3, wherein step (3) comprises:
(3.1) expanding outwards for one circle along the boundary of the feasible region of the target cutter shaft after final updating by using a dilate function, and then subtracting the feasible region of the target cutter shaft before expansion by using an addWeighted function to obtain an expanded boundary;
(3.2) performing collision detection on the cutter shaft direction in the expanded boundary, adding the cutter shaft direction which does not collide to the target cutter shaft feasible region to obtain an updated target cutter shaft feasible region, and marking the cutter shaft direction which has undergone collision detection in the target array;
(3.3) obtaining the expansion boundary of the updated target cutter shaft feasible region, and returning to execute the step (3.2) based on the expansion boundary of the updated target cutter shaft feasible region until all results of cutter shaft direction collision detection in the expansion boundary are infeasible.
6. A solution system of five-axis machining arbor feasible region is characterized by comprising:
the initial boundary calculation module is used for acquiring the cutter shaft feasible region of the previous cutter contact and converting the cutter shaft feasible region into a binary image, taking the binary image as the initial cutter shaft feasible region of the current cutter contact, and calculating the boundary of the initial cutter shaft feasible region of the current cutter contact;
the boundary contraction module is used for performing collision detection on the cutter shaft directions in the boundary, setting all pixels corresponding to infeasible cutter shaft directions as 0 if the collided cutter shaft directions appear, updating the initial cutter shaft feasible region to obtain a new cutter shaft feasible region, and continuously searching the boundary of the new cutter shaft feasible region until all the cutter shaft directions in the boundary are the feasible cutter shaft directions without collision;
and the boundary expansion module is used for expanding a circle outwards along the boundary of the finally updated target cutter shaft feasible region, subtracting the expanded target cutter shaft feasible region to obtain an expanded boundary, performing collision detection on the expanded boundary, finishing the boundary expansion process if all the cutter shaft directions are infeasible, adding the feasible cutter shaft directions into the target cutter shaft feasible region if the feasible cutter shaft directions exist, and repeatedly executing the operation of the boundary expansion module after updating until all the cutter shaft directions are infeasible.
7. The system of claim 6, wherein the arbor runnability field is T-np＞cosθcAnd T.fp＞cosθcTwo constraint conditions, and no interference collision, wherein T represents the cutter shaft direction, npRepresenting the normal vector of the curved surface at the point of contact P of the knife, fpDenotes the feed direction at P, θcIndicating the cutter axis direction T and the curved surface normal direction npOr the size of the included angle between the cutter shaft direction T and the feeding direction fpThe size of the included angle.
8. The system according to claim 7, wherein the initial boundary finding module is specifically configured to obtain an arbor feasible region of a previous tool contact and convert the arbor feasible region into a binary image, use the binary image as an initial arbor feasible region of a current tool contact, and find the boundary of the initial arbor feasible region using a boundary finding findContours function in OpenCV.
9. The system of any one of claims 6 to 8, wherein the boundary contracting module comprises:
the first collision detection module is used for performing collision detection on the cutter shaft direction in the boundary of the feasible region of the initial cutter shaft according to the coordinate of the current cutter position point, the normal vector of the curved surface and the feeding direction, reserving the feasible cutter shaft direction, setting all pixels corresponding to the infeasible cutter shaft direction as 0, and marking the cutter shaft direction which is subjected to collision detection in a target array, wherein the size of the target array is the same as that of the feasible region of the initial cutter shaft;
and the boundary contraction submodule is used for updating the initial cutter shaft feasible region to obtain a new cutter shaft feasible region according to the collision detection result in the first collision detection module, acquiring the boundary of the new cutter shaft feasible region, and repeatedly executing the operation of the first collision detection module based on the boundary of the new cutter shaft feasible region until all collision detection results are that all boundary cutter shaft directions are feasible.
10. The system of any one of claims 6 to 8, wherein the boundary expansion module comprises:
the extended boundary solving module is used for extending outwards for a circle along the boundary of the finally updated target cutter shaft feasible region by using a dilate function, and then subtracting the target cutter shaft feasible region before extension by using an addWeighted function to obtain an extended boundary;
the second collision detection module is used for performing collision detection on the cutter shaft direction in the expanded boundary, adding the cutter shaft direction which does not collide to the target cutter shaft feasible region to obtain an updated target cutter shaft feasible region, and marking the cutter shaft direction which is subjected to collision detection in the target array;
and the boundary expansion submodule is used for solving the expansion boundary of the updated target cutter shaft feasible region, and returning to execute the operation of the second collision detection module based on the expansion boundary of the updated target cutter shaft feasible region until all cutter shaft direction collision detection results in the expansion boundary are infeasible.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910902859.4A CN110658783B (en) | 2019-09-24 | 2019-09-24 | Solving method and system for feasible region of five-axis machining cutter shaft |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910902859.4A CN110658783B (en) | 2019-09-24 | 2019-09-24 | Solving method and system for feasible region of five-axis machining cutter shaft |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110658783A true CN110658783A (en) | 2020-01-07 |
| CN110658783B CN110658783B (en) | 2020-10-16 |
Family
ID=69038756
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910902859.4A Active CN110658783B (en) | 2019-09-24 | 2019-09-24 | Solving method and system for feasible region of five-axis machining cutter shaft |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110658783B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113848803A (en) * | 2021-10-14 | 2021-12-28 | 成都永峰科技有限公司 | Method for generating tool path for machining deep cavity curved surface |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102621928A (en) * | 2012-04-01 | 2012-08-01 | 浙江大学 | Method for generating pose angle feasible regions of five-axis tools quickly |
| KR101571973B1 (en) * | 2014-05-29 | 2015-11-25 | 경북대학교 산학협력단 | Tiling Axis Measuring Method for Multi-axis Machine Tool with a Tilting Rotary Table |
| CN105785919A (en) * | 2016-05-04 | 2016-07-20 | 苏州科技学院 | Point cloud five-axis no-global-interference cutter axis vector feasible domain calculation method |
| CN107065770A (en) * | 2017-05-02 | 2017-08-18 | 浙江大学 | High-speed machining cutter shaft method for fairing based on cutter shaft discretization feasible zone |
| CN108519758A (en) * | 2018-03-21 | 2018-09-11 | 南京工业大学 | A kind of multiaxis NC maching bulb generating tool axis vector planing method avoided interference with flutter |
| CN108983698A (en) * | 2018-07-09 | 2018-12-11 | 华中科技大学 | A kind of optimal tool orientation method and system based on multi-objective restriction |
| CN110134062A (en) * | 2019-04-17 | 2019-08-16 | 华中科技大学 | A kind of multi-axis NC Machine Tools machining path optimization based on intensified learning |
-
2019
- 2019-09-24 CN CN201910902859.4A patent/CN110658783B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102621928A (en) * | 2012-04-01 | 2012-08-01 | 浙江大学 | Method for generating pose angle feasible regions of five-axis tools quickly |
| KR101571973B1 (en) * | 2014-05-29 | 2015-11-25 | 경북대학교 산학협력단 | Tiling Axis Measuring Method for Multi-axis Machine Tool with a Tilting Rotary Table |
| CN105785919A (en) * | 2016-05-04 | 2016-07-20 | 苏州科技学院 | Point cloud five-axis no-global-interference cutter axis vector feasible domain calculation method |
| CN107065770A (en) * | 2017-05-02 | 2017-08-18 | 浙江大学 | High-speed machining cutter shaft method for fairing based on cutter shaft discretization feasible zone |
| CN108519758A (en) * | 2018-03-21 | 2018-09-11 | 南京工业大学 | A kind of multiaxis NC maching bulb generating tool axis vector planing method avoided interference with flutter |
| CN108983698A (en) * | 2018-07-09 | 2018-12-11 | 华中科技大学 | A kind of optimal tool orientation method and system based on multi-objective restriction |
| CN110134062A (en) * | 2019-04-17 | 2019-08-16 | 华中科技大学 | A kind of multi-axis NC Machine Tools machining path optimization based on intensified learning |
Non-Patent Citations (2)
| Title |
|---|
| PENGCHENG HU 等: "Automatic Generation of Five-Axis Continuous", 《IEEE TRANSACTIONS ON AUTOMATION SCIENCE AND ENGINEERING》 * |
| PENGCHENG HU 等: "Boundary-conformed tool path generation based on global reparametrization", 《2015 14TH INTERNATIONAL CONFERENCE ON COMPUTER-AIDED DESIGN AND COMPUTER GRAPHICS》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113848803A (en) * | 2021-10-14 | 2021-12-28 | 成都永峰科技有限公司 | Method for generating tool path for machining deep cavity curved surface |
| CN113848803B (en) * | 2021-10-14 | 2023-09-12 | 成都永峰科技有限公司 | Deep cavity curved surface machining tool path generation method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110658783B (en) | 2020-10-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111323037B (en) | Voronoi path planning algorithm for novel framework extraction of mobile robot | |
| CN113251919B (en) | Coordinate transformation-based cylinder point cloud data fitting method and device | |
| EP1989685B1 (en) | A method for comparing a first computer-aided 3d model with a second computer-aided 3d model | |
| CN109559346B (en) | Method for positioning and dividing part to be measured in 3D point cloud measurement and scanner | |
| CN113741426B (en) | Robot machining path planning method based on local point cloud curve fitting | |
| US11024022B2 (en) | Data generation method and data generation device | |
| JP4905285B2 (en) | Apparatus, method and program for creating tool reference plane | |
| CN110658783B (en) | Solving method and system for feasible region of five-axis machining cutter shaft | |
| CN115311172A (en) | Map area segmentation method and related device | |
| CN114545430A (en) | Tray pose identification method and system based on laser radar | |
| CN113878592B (en) | Workpiece cutting method and device based on laser locating and cutting robot | |
| CN112906215B (en) | Pipe tool path generation method based on SolidWorks secondary development | |
| CN115147433A (en) | Point cloud registration method | |
| CN116604553A (en) | Application of robot handwriting system for skeleton extraction method | |
| CN113592976B (en) | Map data processing method and device, household appliance and readable storage medium | |
| CN113670253B (en) | Space target attitude inversion method and device, computing equipment and storage medium | |
| CN110348163B (en) | Fitting method for continuous tangent circular arc of tire pattern boundary | |
| CN110603535B (en) | Iterative multi-directional image search supporting large template matching | |
| CN114089692A (en) | Rapid numerical control programming method suitable for complex and long surface of part | |
| CN111337036A (en) | Overlap region data optimization method and device and terminal equipment | |
| CN115272081A (en) | Full-automatic high-precision splicing method based on multi-station laser point cloud data | |
| CN112052909B (en) | Pattern matching method, device, electronic equipment and storage medium | |
| CN116068964B (en) | Automatic generation method of control instruction of numerical control machine tool and related equipment | |
| CN117745719B (en) | Extraction method of robot weld milling track | |
| CN113435256B (en) | Three-dimensional target identification method and system based on geometric consistency constraint |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |