The processing method of the numerically-controlled machine tool closed loop system of view-based access control model
Technical field
The present invention relates to numerically-controlled machine tool control technology field, more specifically to a kind of numerically-controlled machine tool of view-based access control model
The processing method of closed loop system.
Background technology
Numerically-controlled machine tool is divided into three kinds of open loop, semiclosed loop and closed loop control modes.Open-loop NC lathe is not fed back, and precision is not
It is high;Semiclosed loop numerically-controlled machine tool does feedback element with the pulse coder on motor, can control the rotating speed of motor, and precision is higher;
Closed loop digital control lathe does position feedback elements, precision highest with grating scale.
Numerically-controlled machine tool cuts down the material on blank with cutter, to coincide with design object, but either semiclosed loop and closed loop,
The cutting down as a result, working angles are not included in the closed loop of control on blank all without control cutter.If cutting
Process is also included in control closed loop, controls the processing result of each step in process, can improve machining accuracy.
Therefore, the prior art is urgently greatly improved.
Invention content
The technical problem to be solved in the present invention is, in view of the above-mentioned defects in the prior art, provide a kind of view-based access control model,
The closed loop system of workpiece three-dimensional appearance, the workbench including half-closed loop control, the measurement list for forming closed-loop are measured in real time
First, analysis computing unit, the cutter holder and cutter of processing, it is specific as follows:
Measuring unit therein is in flange plate-like, is installed at by cutter holder with rolling bearing, on handle of a knife, measuring unit is not with knife
Tool rotation, but is moved with cutter, measuring unit be radially equidistantly equipped with it is several to laser emitter and camera, at camera
In on the large circle of outside, laser emitter is on the small circle ring of the inside, the air line distance between laser emitter and camera
Distance between the most normal operating position of measuring unit to workpiece is roughly equal, the distance of laser emitter and camera, laser
The distance of Laser Curve, camera and Laser Curve that transmitter is projected in workpiece surface, three edge lengths approximately equals are formed
Close triangle;
Laser emitter sends out line-styled laser straight down, and line-styled laser is presented with the fluctuating of piece surface
Different shapes, the optical axis direction laser rays direction deflection of camera;The optical axis direction of camera on vertical vertical direction not
It is to install straight down, but to cutter there are one deflection angle, the optical axis direction tool deflection of camera, deflection angle causes
On the most normal operating position of workpiece, the laser rays that laser is sent out passes through the center of camera imaging image, in the most upper of workpiece
The imaging for the laser rays that most upper operating position is formed on operating position, most descending to be formed on operating position and most descend working position in workpiece
The imaging of laser rays is put, laser rays is imaged within the marginal belt of camera image, and the field range of two cameras
Overlapping;Laser emitter and camera are alternate one by one, a measuring unit at least three pairs of laser emitters and camera, with
Workpiece surface forms the laser wire shaped of closing;The straight line of laser, laser emitter and camera that laser emitter is sent out away from
With a distance from, laser rays to camera, three sides form a closing triangle, each point that cutter passes through can front and back
Camera at least measure twice;
The analysis computing unit forms closed loop system together with original half-closed loop control workbench, and analysis calculates
Unit calculates the pattern of workpiece surface according to Vector triangle according to collected laser rays location and shape are imaged;Due to work
Part modification of surface morphology, projects to imaged shape of the laser of workpiece surface in camera, position can change, and laser is straight
Line can become Laser Curve, and workpiece surface is become the workpiece surface after processing action by the workpiece surface before processing action, laser
Image space can be become the distance between laser emitter and camera by the imaging of laser rays on the workpiece surface after processing action,
The distance of laser emitter and camera and measuring unit equal, the laser to the most normal positional distance between the most normal operating position of workpiece
Transmitter and camera composition are close-shaped, each point that cutter passes through can be at least measured twice, in this closed-loop
In system each processing action of cutter can obtain corresponding processing effect and and desired effect deviation, and can build
The correspondence of machined parameters and processing effect is found out, the three-dimensional appearance before the processing that can also reconstruct and after processing.
Preferably, the cutter of implementation is moved towards each direction, at least there are one camera it is observed that laser rays, can weigh
Build the surface topography of workpiece.
Preferably, the distance between workpiece and measuring unit, workpiece are in maximum distance position or in most narrow spacings
It offs normal and puts, the visual field of adjacent camera will have an overlapping, and the visual field of adjacent camera is illegal without the operating position being overlapped
Operating position.
A kind of processing method of the numerically-controlled machine tool closed loop system of view-based access control model completes time processing and includes scanning work
Platform, fixture and model, scan hair go bad and model, process, four steps of process finishing, respectively it is as follows:
Step S1. scanning workbench, fixture simultaneously model
Workbench, fixture are scanned with measuring unit, establish the threedimensional model of workbench, fixture.Input lathe ginseng
Number, such as the cutter situation of the deformation parameter of the limit velocity of workbench extreme position, lathe, lathe, lathe;
Step S2. scanning hairs are gone bad and are modeled
Same scanning workbench, fixture and model it is the same, during processing before input editing objective threedimensional model and surface want
It asks, then hair is badly scanned with measuring unit, establishes the threedimensional model of blank.
Step S3. processing, dynamic adjustment stage property track
Blank is aligned with editing objective, the threedimensional model of threedimensional model and blank to editing objective asks poor, according to machine
Bed maximum stepping, minimum step, lathe shake etc. parameters, automatically generate processing action sequence;
Analysis computing unit driving lathe is started to process by the processing action sequence being generated in advance.In process, cutter
It often moves and moves a step, camera calculates the cutter after cell location processing to measuring the closing laser line imaging around cutter, analysis
Track rebuilds workpiece surface appearance, feeds back processing effect, and the deviation of calculating and desired effect, establishes and correct machined parameters
With the correspondence of processing effect, while the processing action sequence being generated in advance according to processing effect amendment:
Step S31:Analysis computing unit driving lathe is started to process by the processing action sequence being generated in advance;
Step S32:In process, cutter is often moved and is moved a step, camera to measure cutter around closing laser rays into
Picture;
Step S33:Analysis calculates the cutter path after cell location processing, rebuilds workpiece surface appearance;
Step S34:Processing effect, and the deviation of calculating and desired effect are fed back, establishes and correct machined parameters and processing
The correspondence of effect;
Step S35:It is formed according to the processing effect of step S34 and corrects processing action sequence, continue to process.
Step S4. process finishings
During process finishing, according to measurement result, the parameters such as size, the surface requirements of workpieces processing are exported.
Preferably, allow the distance of laser emitter and camera and the distance of measuring unit to workpiece surface roughly equal;
Preferably, the distance between workpiece and measuring unit, workpiece are in maximum distance position or in most narrow spacings
It offs normal and puts, the visual field of adjacent camera will have an overlapping, and the visual field of adjacent camera is illegal without the operating position being overlapped
Position;
Preferably, distance of the focal length of laser emitter for measuring unit to workpiece surface is adjusted;
Preferably, whole light on machining tool are closed, to protrude brightness of the laser in workpiece surface.
Preferably, the cutting fluid on machining tool is closed, to improve the accuracy of camera acquisition.
Preferably, it is processed using small stride, to avoid waste cut materials are rolled, improves the accurate of camera acquisition laser rays
Degree.
Preferably, according to the waste cut materials rolled higher than workpiece before processing, analysis computing unit can identify what is rolled
Waste cut materials.
The present invention has had the advantage that:The processing action effect after each movement of cutter can be measured in real time, rebuild processing
The surface quality of processing is also included in the control system of closed-loop by pattern in the process such as roughness, can exponentially be improved
Machining accuracy;Due to it is each action have feedback, can accurate recognition go out lathe shake etc. parameters and dynamic characteristic, energy
Compensation is automatically performed, the processing quality of lathe is improved in the case where lathe is constant;Due to having input the three-dimensional mould of editing objective
Type, it is bad also to scan hair, processing action sequence can be planned automatically in analysis computing unit, before being compensated automatically in process
The error of face processing action can be automatically stopped after reaching the quality of requirement, therefore can be completed to higher the degree of automation processing and be appointed
Business.
Description of the drawings
Fig. 1 is the structure diagram of the numerically-controlled machine tool closed loop system the present invention is based on vision.
Fig. 2 is the measuring unit schematic diagram of the numerically-controlled machine tool closed loop system the present invention is based on vision.
Fig. 3 is the in-process measurement schematic diagram of the numerically-controlled machine tool closed loop system of view-based access control model.
Fig. 4 be the numerically-controlled machine tool closed loop system of view-based access control model process in laser, laser, camera and cutter
Position relationship schematic diagram.
Fig. 5 is the time processing process calculation process schematic diagram of the numerically-controlled machine tool closed loop system of view-based access control model.
In figure:
1st, cutter holder
2nd, cutter
3rd, laser emitter
4th, measuring unit
5th, camera
6th, the air line distance between laser emitter and camera
7th, the overlapped view of adjacent camera
8th, the field range of camera
9th, the laser rays (viewing angle of laser emitter) seen straight down
10th, the laser rays (slanting viewing angle) that camera is seen
11st, the most upper operating position of workpiece
12nd, the imaging of the laser rays of most upper operating position
13rd, workpiece most descends operating position
14th, the imaging of operating position laser rays is most descended
15th, on the workpiece surface before processing action laser rays imaging
16th, the workpiece surface before processing action
17th, the workpiece surface after processing action
18th, on the workpiece surface after processing action laser rays imaging
19th, the most normal operating position of workpiece
20th, laser rays straight down
21st, workpiece
22nd, deflection angle
Specific embodiment
For CNC milling machine, present invention specific implementation is as follows:
As shown in Figs. 1-5, the numerically-controlled machine tool closed loop system of a kind of view-based access control model, basic thought are real in process
When measure the three-dimensional appearance of part, to improve the precision of processing, specifically include the workbench of half-closed loop control, form closed-loop
Measuring unit, analysis computing unit, processing cutter holder and cutter,
Measuring unit 4 therein such as attached drawing 2, in flange plate-like, be installed at by cutter holder 1 with rolling bearing, on handle of a knife, not with
Cutter 2 rotates, but is moved with cutter 2, measuring unit 4 be radially equidistantly equipped with it is several to laser emitter 3 and camera 5,
Camera 5 is on the large circle of outside, and laser emitter 3 is on the small circle ring of the inside, in order to improve the accuracy of measurement,
Air line distance 6 and measuring unit 4 between laser emitter and camera to the distance between the most normal operating position 19 of workpiece substantially
It is equal, air line distance 6, laser emitter 3 between laser emitter and camera 21 surface projection of workpiece Laser Curve, take the photograph
As head and the distance of Laser Curve, three edge lengths approximately equals form closing triangle;
Laser emitter 3 sends out line-styled laser straight down, line-styled laser can with the fluctuating of piece surface and
Different shapes is presented, realizes Laser Curve 10 observe, on curved surface, multiple cameras 5 are in the mounting surface of measuring unit 4
On the center of circle is installed in radiation-like, the deflection of the optical axis direction laser rays direction of camera;The optical axis direction of camera 5 is vertical vertical
It is not to install straight down on direction, but has deflection angle 22 to 2 direction of cutter, deflection angle 22 meets the following conditions:
On the most normal operating position 19 of workpiece, the laser rays 9 that laser is sent out passes through the center of camera imaging image, in workpiece
Most upper operating position 11 formed most upper operating position laser rays imaging 12, formed in most descending on operating position 13 for workpiece
Most descend the imaging 14 of operating position laser rays, the laser rays that laser emitter 3 is sent out camera 5 into image marginal belt with
It is interior, and the field range 8 of two neighboring camera should partly overlap, and the as overlapped view 7 of adjacent camera, guarantee is every
Laser rays can be acquired completely;Laser emitter 3 and camera 5 are alternate one by one, at least three pairs of a measuring unit 4
Laser emitter 3 and camera 4, to be formed the laser rays of closing in workpiece surface, no matter cutter 2 moves to which direction, until
It is few there are one camera 5 it is observed that laser rays, the surface topography of workpiece can be rebuild;Laser emitter 3 send out it is vertical to
Under laser rays 20, laser rays (the slanting viewing angle seen of the air line distance 6 between laser emitter and camera, camera
Degree) 10 closing triangles are formed to three sides of distance of camera 5, cutter can be by front and back by each point of workpiece
Camera at least measures twice;
Since workpiece surface appearance changes, imaged shape of the laser of workpiece surface in camera 5, position meeting are projected to
It changes, if the laser in Fig. 3 is in the straight line of vertical direction, the laser rays as seen straight down be (laser emitter
Viewing angle) 9 become Laser Curve in camera visual angle, the laser rays (slanting viewing angle) that as camera is seen
10, and workpiece surface becomes the workpiece surface 17 after processing action by the workpiece surface 16 before processing action in Fig. 4, laser into
Image position can become laser on the workpiece surface after processing action by the imaging 15 of laser rays on the workpiece surface before processing action
The imaging 19 of line.
The analysis computing unit together with original half-closed loop control workbench as shown in Figure 1, form closed loop
System, analysis computing unit calculate workpiece surface according to 5 collected laser rays location and shape of camera shooting according to Vector triangle
Pattern.In order to improve the accuracy of measurement, the distance 6 of laser emitter and camera is allowed to arrive the most normal work of workpiece with measuring unit 4
The distance made between position 19 is roughly equal.Due between laser emitter and camera air line distance 6, laser emitter 3 is in work
The distance of the Laser Curve of 21 surface projection of part, camera and Laser Curve, three edge lengths approximately equals form closing triangle
Shape, thus cutter 2 pass through each point can at least be measured twice, so in this closed loop system cutter 2 it is every
A processing action (can be understood as a line G code) can obtain corresponding processing effect and and desired effect deviation, and
The correspondence of lathe parameter, machined parameters and processing effect, dynamic tuning lathe parameter can be established out.It is this to refine to often
The closed loop system of a processing action, according to the lathe parameter adjusted in real time, dynamic adjusts machined parameters, obtains more accurately adding
Work efficiency fruit.
A kind of processing method of the numerically-controlled machine tool closed loop system of view-based access control model completes time processing and includes scanning work
Platform, fixture and model, scan hair go bad and model, process, four steps of process finishing, as shown in figure 5, content difference it is as follows:
Step S1. scanning workbench, fixture simultaneously model
Workbench, fixture are scanned with measuring unit, establish the threedimensional model of workbench, fixture.Input lathe ginseng
Number, such as the cutter situation of the deformation parameter of the limit velocity of workbench extreme position, lathe, lathe, lathe;
Step S2. scanning hairs are gone bad and are modeled
Same scanning workbench, fixture and model it is the same, during processing before input editing objective threedimensional model and surface want
It asks, then hair is badly scanned with measuring unit, establishes the threedimensional model of blank;
Step S3. processing, dynamic adjustment stage property track
Blank is aligned with editing objective, the threedimensional model of threedimensional model and blank to editing objective asks poor, according to machine
Bed maximum stepping, minimum step, lathe shake etc. parameters, automatically generate processing action sequence;
Analysis computing unit driving lathe is started to process by the processing action sequence being generated in advance.In process, cutter
It often moves and moves a step, camera calculates the cutter after cell location processing to measuring the closing laser line imaging around cutter, analysis
Track rebuilds workpiece surface appearance, feeds back processing effect, and the deviation of calculating and desired effect, establishes and correct machined parameters
With the correspondence of processing effect, while the processing action sequence being generated in advance according to processing effect amendment:
Step S31:Analysis computing unit driving lathe is started to process by the processing action sequence being generated in advance;
Step S32:In process, cutter is often moved and is moved a step, camera to measure cutter around closing laser rays into
Picture;
Step S33:Analysis calculates the cutter path after cell location processing, rebuilds workpiece surface appearance;
Step S34:Processing effect, and the deviation of calculating and desired effect are fed back, establishes and correct machined parameters and processing
The correspondence of effect;
Step S35:It is formed according to the processing effect of step S34 and corrects processing action sequence, continue to process.
Step S4. process finishings
During process finishing, according to measurement result, the parameters such as size, the surface requirements of workpiece are exported.
In the present embodiment, the distance between workpiece 21 and measuring unit 4, workpiece 21 be in maximum distance position or
In minimum distance position, the visual field of adjacent camera will have an overlapping, and the visual field of adjacent camera 5 is without the working position that is overlapped
It is illegal operating position to put;The focal length for adjusting laser emitter 3 arrives the distance on 21 surface of workpiece for measuring unit 4;It closes and adds
Whole light on work lathe, to protrude brightness of the laser in workpiece surface;The cutting fluid on machining tool is closed, is taken the photograph with improving
As the accuracy of first 5 acquisitions;It is processed using small stride, to avoid waste cut materials are rolled, improves the standard of camera acquisition laser rays
Exactness;According to the waste cut materials rolled higher than workpiece before processing, analysis computing unit can identify the waste cut materials rolled.
One embodiment of the present of invention is described in detail above, but the content is only the preferable implementation of the present invention
Example, it is impossible to be construed as limiting the practical range of the present invention.All all the changes and improvements made according to the present patent application range
Deng, should all still belong to the present invention patent covering scope within.