TWI592251B - Image three-dimensional spatial error detection method and system - Google Patents

Description

Image type multi-axis machine tool calibration method and system thereof

The invention relates to an image multi-axis machine tool calibration system, in particular to an image multi-axis machine tool calibration method and system thereof for detecting a multi-axis machine tool.

With the continuous improvement of industrial technology, the processing quality, precision and processing time of products have become important competitive indicators, and the accuracy detection of machine tools is a long-standing problem, and the source of precision error affecting machine tools can be roughly divided into static. Two categories, such as error and dynamic error, the static error can be subdivided into structural geometric error, static and dynamic yaw error of working platform, thermal deformation error and volume error, etc., and dynamic error can be divided. For loop gain mismatch, viscous sliding accidental brakes, etc., the above listed errors will affect the performance of the tool implement. In the current draft of the International Organization for Standardization (ISO), a five-axis machine tool is required. The co-movement error must be within 40 micrometers (μm), and in order to achieve this standard, it is the most effective and direct way to establish the accuracy of the machine tool and improve the quality of the product.

The measurement system of the existing machine tool has been developed for a long time. The following describes the detection technology and problems of the current five-axis machine tool:

1. The Double Ball Bar (DBB), also known as the Round Ball Bar, is mainly used to measure the circular motion by a magnetic double club with a built-in and retractable moving measuring component. The error generated, but the dynamic total error of the measuring five-axis machine tool is limited, and the full working space cannot be corrected. Therefore, the dynamics of the rotating shaft of the five-axis machine tool must be measured by different paths. Errors and geometric errors are relatively inconvenient and time consuming to use;

2. Measuring tilt axis positioning error gauge (API, Automated Precision Inc), the motion path of the tilt axis is a cycloid type, mainly using its rotation center to measure the vertical axis and tilt axis error, and can also be matched API 5/6D and XD Laser (six-dimensional laser interferometer) simultaneously measure six errors of the linear axis, including one position error, two straightness errors, and three angular errors, but the price is extremely expensive.

3. Probe-Ball can directly measure the measuring device of the five-axis tool machine assembly error, so as to evaluate the accuracy of the five-axis machine tool, which can directly measure the position error of the five-axis machine tool. The measured data and the constructed probe, however, the carbon head-ball error model can be accurately estimated by the least square error estimation method for some error items that cannot be directly measured;

4. In the existing technology (for example, company: IBS Precision Engineering), a R-test (Rotary Axis analyzer) system has been developed, which is capable of measuring the error of the static error and dynamic error of the five-axis machine tool. However, it can only obtain the assembly error. Therefore, the application of various geometric errors and dynamic error analysis of the five-axis machine tool is still quite limited.

Furthermore, the current detection technology and problems related to the rotating shaft are as follows. At present, the rotating shaft cannot be measured. Since the rotating shaft does not have an interferometer, it can receive 360-degree signals for use as a measurement reference, among which Renishaw XR20- W (wireless rotary axis corrector) and HP-E5290C (laser interferometer), mainly using an external high-precision rotating platform with a laser interferometer as a measurement reference to detect the upper and lower machine tool rotation axes The error is mainly caused by the rotating platform being erected on the rotating shaft of the machine tool. When a positive rotation signal is input on the rotating shaft, a high-precision rotating platform is used to input a same inverted signal, and then used. The interferometer detects the relative error between the two axes of rotation so that only the optical encoder or optical scale error between the two axes of rotation is measured.

In summary, it can be found that there are still many problems in the existing measuring devices for multi-axis machine tools. Therefore, how to measure and compensate the errors for multi-axis machine tools is a key technology at present, and it is really necessary. Improve it.

Therefore, the present invention has been developed in view of the existing multi-axis machine tool measuring device, which has the disadvantages of inconvenience in operation and high measurement cost, and has been continuously tested and researched to finally develop a present invention which can improve the existing defects.

The invention mainly provides an image multi-axis machine tool calibration method and a system thereof, which are mainly wirelessly modularized by a charge-coupled device (CCD), and the intercepted image signal is wirelessly transmitted to The program in the computer performs signal processing. Therefore, it is no longer necessary to go through the signal amplifier and other devices to achieve the measurement purpose, and can be directly measured with the laser, thereby providing a convenient assembly, automatic measurement compensation, and reduction. The purpose of the image detection system that measures the cost and improves the accuracy of the machine tool.

Based on the above objective, the main technical means of the present invention is to provide an image type multi-axis machine tool calibration system, which is provided with a sensor head, a standard ball group and a signal processing group, wherein: the sensor head is provided with a sensing group, the sensing group is provided with a wireless module and a light source, wherein the wireless module is provided with a wireless transmitter and an image capturing device, the light source provides sufficient intensity of light output to make the image capturing device clear Identifying an object and capturing the image; the standard ball set is provided with a fixed seat, a support rod, a standard ball and a magnetic seat, the standard ball is fixed on the support rod, and the support rod is fixed on the support rod Inserting a standard ball into the measuring range of the sensing group of the sensing head; and connecting the signal processing group to the sensing head and providing a wireless transceiver, the wireless transceiver and the wireless transceiver The wireless transmitters of the sensing group are connected to receive signals output by the wireless transmitters for program operation and analysis processing.

The sensing group can be two sets of surface image capturing devices or three sets of line image capturing devices, and provide sufficient light source intensity to perform image recognition of the object to be tested, and transmit the image to the wireless transmitter through the wireless transmitter. Signal processing group.

Among them, the standard ball material can be metal, plastic, ore.

The signal processing group can be a computer.

The signal processing group can be a single chip.

Further, an embodiment of the present invention provides an image multi-axis machine tool calibration method, which comprises the following steps: an installation step: combining the sensor head and the standard ball group with a spindle of a multi-axis tool machine to be tested Between the working platform, the standard sphere on the support rod is disposed in the measurement space of the sensing head and located between the measurement ranges of the two sensing groups; the detecting step: moving the multi-axis to be tested The X-axis and Y-axis of the machine tool enable the light output of the light source to enable each image capture device to recognize the standard sphere, and transmit the generated image signal to the corresponding wireless transmitter and wireless transceiver to In the signal processing group, the center change position of the sphere is calculated and analyzed, and the image signals captured by the two wireless modules are processed, and the sensing signals of one wireless module can measure the Y-axis and the Z-axis. Offset, and the sensing signal of another wireless module can measure the offset of the X-axis and the Z-axis; and the detection method: input the X, Y coordinate of the tool to be tested, by the center position of the standard ball Poor position with the input coordinates, and The error value of the multi-axis machine tool to be tested is converted into a compensation value wireless signal corresponding to the error value, and the compensation value signal is transmitted to the controller of the multi-axis machine tool to be tested, The controller performs an automated error compensation for the multi-axis machine tool to be tested.

The mounting method of the sensing head is: the sensing head is set with a fixed end as a reference, and the standard ball group is fixed with a moving end, so that the standard ball located on the supporting rod is set on the measuring head. In the space and between the measurement ranges of the two sensing groups, the fixed end can be a machine tool spindle or the like; the mobile end can be a machine tool working platform or the like.

Alternatively, the sensing head is installed by: locating the sensing head with a moving end, and the standard ball group is fixed with a fixed end as a reference, so that the standard ball located on the supporting rod is disposed on the measuring head. In the space and between the measurement ranges of the two sensing groups, the fixed end can be a machine tool spindle or the like; the mobile end can be a machine tool working platform or the like.

Wherein, the detecting method is to sense the position change of the three-dimensional direction (X, Y, Z) of the center of the ball to be tested by the sensing group provided by the present invention.

Wherein, the tool machine error value is set on the multi-axis machine tool to be tested by the sensing set provided by the present invention, and the multi-axis machine tool to be tested inputs the detection path, and the sensing group senses the center position of the standard ball. Compared with the difference of the input coordinate position of the multi-axis machine tool, the position error of each direction of the multi-axis machine tool X, Y and Z to be tested can be obtained from the position difference between the two.

According to the above technical means, the image multi-axis machine tool calibration method and system thereof are mainly for measuring the multi-axis machine tool through each wireless module, and transmitting the captured image to the wireless transmission system. The computer or single chip of the signal processing group is processed by the program, and then the compensation signal is sent to the controller of the multi-axis machine tool, thereby performing dynamic measurement, static measurement, analysis and measurement data for the multi-axis machine tool, and simply performing The error compensation system can be used as a tool length setter to effectively provide an image detection method and system that can facilitate assembly, automatic measurement and compensation, reduce measurement cost, and improve the accuracy of the machine tool.

01‧‧‧Multi-axis machine tool

02‧‧‧ Spindle

03‧‧‧Working platform

10‧‧‧Sensing head

11‧‧‧Upper cover

12‧‧‧Under the cover

13‧‧‧ Connecting rod

141‧‧‧First wireless module

142‧‧‧Second wireless module

151‧‧‧First light source

152‧‧‧second light source

16‧‧‧ Slider

17‧‧‧Image capture device

18‧‧‧ lens

19‧‧‧Wireless transmitter

20‧‧‧Standard ball fixed group

21‧‧‧Standard ball

22‧‧‧Support rod

23‧‧‧ Fixed seat

24‧‧‧magnetic seat

1 is a perspective view showing the image multi-axis machine tool calibration system of the present invention disposed on a multi-axis machine tool.

2 is a perspective view of the sensing head of the image type multi-axis machine tool calibration system of the present invention.

3 is an exploded perspective view of the wireless module of the sensing head of the present invention.

4 is a perspective external view of a standard ball fixed group corrected by the image type multi-axis machine tool of the present invention.

Figure 5 is a perspective view showing the first mounting aspect of the image type multi-axis machine tool calibration system of the present invention disposed on a multi-axis machine tool.

Figure 6 is a perspective view showing the second mounting aspect of the image type multi-axis machine tool calibration system of the present invention disposed on a multi-axis machine tool.

Figure 7 is a block diagram showing the operation of the image multi-axis machine tool calibration system of the present invention.

In order to understand the technical features and practical effects of the present invention in detail, and in accordance with the contents of the specification, the following is further described in detail with reference to the preferred embodiments shown in the drawings, as shown in FIG. The image multi-axis machine tool calibration system of the invention is disposed on a multi-axis machine tool 01, wherein the multi-axis machine tool 01 is provided with a spindle 02, a working platform 03 and a controller, and the image multi-axis of the invention The machine tool calibration system comprises a sensor head 10, a standard ball fixed group 20 and a signal processing group, wherein: As shown in FIG. 2 and FIG. 3, the sensing head 10 is combined with the multi-axis machine tool 01 and is provided with an upper cover 11, a lower cover 12, at least one sensing group and a connecting rod 13, further, such as As shown in FIG. 5 and FIG. 6 , the sensing head 10 can be fixedly coupled with the main shaft 02 or the working platform 03 of the multi-axis machine tool 01 , wherein the upper cover 11 and the lower cover 12 are arranged in parallel to form a measurement. a space is provided, and the upper cover 11 is provided with a through hole for extending a sensing object into the measuring space. The lower cover 12 is provided with at least one track on the top surface, and the at least one sensing group is disposed on the lower cover 12 The at least one sensing group is provided with a slider 16, a wireless module and a light source, wherein the slider 16 is combined with the track of the lower cover 12, and the wireless module 141, 142 and the The slider 16 is slidably coupled to the track of the lower cover 12. The wireless module is provided with an image capture device 17 (CCD) and a wireless transmitter 19. The image capture device 17 is disposed toward the upper cover 11. A lens 18 is disposed in the direction of the perforation, wherein the combination of the slider 16 and the track provides an adjustment of the image picker 17 The function of the focal length is that the wireless transmitter 19 is disposed in the wireless module 141 and 142 and electrically connected to the image capturing device 17 to wirelessly transmit the image signal of the image capturing device 17 . The measurement head 10 is positioned in the measurement space and provides sufficient light source intensity to enable the image picker 17 to achieve a clear identification of the object.

Further, the sensing head 10 is provided with two sensing groups, and the lower cover 12 is provided with two tracks. The wireless modules of the two sensing groups are a first wireless module 141 and a second wireless module 142, respectively. The two wireless modules 141 and 142 are respectively disposed on the two tracks of the lower cover 12, and the light sources of the two sensing groups are respectively a first light source 151 and a second light source 152, and the image pickers of the two wireless modules are provided. 17 clearly identify the standard ball 21 position. The connecting rod 13 is disposed at the bottom of the lower cover 12, so that the sensing head 10 can be combined with the multi-axis machine tool 01.

Please refer to FIG. 1 and FIG. 4 , the standard ball fixing group 20 is combined with the multi-axis machine tool 01 and faces the sensing head 10 , and the standard ball fixing group 20 is provided with a fixing seat. 23, a support rod 22, a standard ball 21 and a magnetic seat 24, wherein the fixing seat 23 can be fixed on the working platform 03 or the main shaft 02 of the multi-axis machine tool 01 as shown in FIG. 5 and FIG. The support head 10 is disposed on a side surface of the fixing base, and the support rod 22 is fixed to a side surface of the fixing base and extends toward the perforation direction of the sensing head 10. The standard ball 21 is fixed to the support rod. 22 is away from the end of the fixing seat 23 and extends into the measuring space of the sensing head 10 through the through hole. The spherical ball 22 of the present invention is used as the sensing element, and only the spherical body is generated during the measurement. Position error without angular error, so the use of the standard sphere 22 as the sensing element can reduce the occurrence of errors, and the magnetic seat 24 is fixed to one side of the fixing seat 23, thereby providing the standard ball The fixing effect of the fixed group 20 with a magnetic attraction.

The signal processing group is connected to the sensing head 10 and the multi-axis machine tool 01. The signal processing group is provided with a wireless transceiver, and the wireless transceiver is connected with the wireless transmitters 19 of each sensing group to receive each The signal output by the wireless transmitter 19 is subjected to program calculation and analysis processing, and the wireless transceiver is connected to the controller of the multi-axis machine tool 01, thereby controlling the multi-axis machine tool 01 to perform error measurement compensation, and further The signal processing group can be a computer or a single chip.

Referring to FIG. 1 and FIG. 7 , the image multi-axis machine tool calibration system of the present invention is measured for the multi-axis machine tool 01 , wherein the connecting rod of the sensing head 10 can be as shown in FIG. 5 . 13 is combined with the main shaft 02 (fixed end) of the multi-axis machine tool 01, and passes through the magnetic seat 24 and the work The standard ball holding group 20 is fixed on the working platform 03 (moving end) by the magnetic attraction of the platform 03, or the working of the sensing head 10 and the multi-axis machine tool 01 is performed as shown in FIG. The platform 03 (mobile end) is combined, and the standard ball fixing group 20 is fixed on the main shaft 02 (fixed end) by magnetically attracting the magnetic base 24 and the main shaft 02 so as to be located on the support rod. A standard sphere 21 of 22 is disposed in the measurement space of the sensor head 10 and is located between the measurement ranges of the two sensing groups.

After the sensing head 10 and the standard ball fixing group 20 are mounted on the multi-axis machine tool 01, the two light sources 151 and 152 can pass through the X-axis and the Y-axis of the multi-axis machine tool 01. The standard ball 21 is irradiated to the corresponding wireless module, and the image signal generated by each image capturing device 17 is transmitted to the computer of the signal processing group via the corresponding wireless transmitter 19 and the wireless transceiver. In the single chip, the image signals captured by the two wireless modules can be processed, and the Y-axis and the Z-axis can be measured through the sensing signals of the first wireless module 141 as shown in FIG. The offset of the second wireless module 142 can be measured by the sensing signal of the second wireless module 142, and the offset of the X-axis and the Z-axis can be measured, and then the spherical center position of the standard ball 21 can be calculated and analyzed. The multi-axis machine tool 01 error value.

The image capturing device 17 of the first wireless module 141 is parallel to the X-axis direction of the multi-axis machine tool 01 and is provided by the first light source 151. After the light output is output, the image capturing device 17 of the first wireless module 141 can clearly identify the detected object, and the image capturing device 17 of the first wireless module 141 can obtain the Y axis (CCD1Y) and the Z. a signal in the direction of the axis (CCD1Z); and the image capturing device 17 of the second wireless module 142 is parallel to the Y-axis direction of the multi-axis machine tool 01, and the second light source 152 provides sufficient light output to enable the first After the image capturing device 17 of the second wireless module 142 can clearly identify the detected object, the image capturing device 17 of the second wireless module 142 can obtain the signals of the X-axis (CCD2X) and the Z-axis (CCD2Z) direction. . In the embodiment of the present invention, only the light output having sufficient intensity is required to provide the image capturing device 17 in the parallel X-axis direction and the Y-axis direction to detect the object, and it is not limited to include the first light source 151 or the second. The position of the light source 152 or the first light source 151 and the second light source 152 that can be disposed in the sensing head 10 is not limited. The offset of the center of the standard sphere 21 can be obtained by the following formula: the X-axis direction offset of the sphere: ΔX=CCD _2X ; the spherical Y-axis direction offset: ΔY=CCD _1Y And the spherical X-axis direction offset: ΔZ = (CCD _1Z + CCD _2Z ) / 2.

When the computer or single chip of the signal processing group calculates the error value of the multi-axis machine tool 01 through the sensing head 10 and the standard ball 21, it is converted into a compensation value corresponding to the error value. The wireless signal is transmitted to the controller, and the multi-axis machine tool 01 can be automatically compensated for error compensation.

By the above technical means, the image type multi-axis machine tool calibration system of the present invention can be used for backlash detection, static detection, angle detection, knife length setter, etc. of the multi-axis machine tool 01, as follows: In the backlash detection, the standard ball fixed group 20 is fixed to a measuring axis, the measuring shaft is reciprocated, and the backlash error is calculated by the offset of the standard ball 21 and transmitted to the machine For the static detection, the five-axis CNC machine tool in the ISO/CD 10791-6 specification is used to detect the K1, K2, and K4 paths according to the detection parameters (starting angle, end angle, and inter-grid angle). The minimum center method is used to calculate the center-of-center offset to be transmitted to the machine for compensation. The K1 path is detected as A-axis rotation according to the ISO specification parameter setting, and the Y and Z axes are coordinated, by the moving position of the standard ball 21, Obtaining the eccentricity error of the A-axis, the K2 path is detected as the C-axis rotation is set according to the ISO specification parameter, and the X and Y axes are coordinated. By the moving position of the standard sphere 21, the eccentricity error of the C-axis can be obtained, and the K4 path is obtained. Detected as A, C axis rotation in accordance with ISO specifications Setting the number, X, Y, Z-axis moving with, by moving the position of the ball 21 of the standard, to get the total path error.

In summary, the present invention is an image multi-axis machine tool calibration system, which mainly measures the multi-axis machine tool through each wireless module, and transmits the captured image to the wireless transmission to The computer or single chip of the signal processing group performs program processing, and then sends the compensation signal to the controller of the multi-axis machine tool, thereby performing dynamic measurement, static measurement, and analyzing measurement data for the multi-axis machine tool. The error compensation system is implemented and can be used as a tool length setter, thereby effectively providing an image detection system that can facilitate assembly, automatic measurement and compensation, reduce measurement cost, and improve the accuracy of the machine tool.

The above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any one of ordinary skill in the art can use the present invention without departing from the scope of the present invention. Equivalent embodiments of the invention may be made without departing from the technical scope of the present invention.

10‧‧‧Sensing head

11‧‧‧Upper cover

12‧‧‧Under the cover

141‧‧‧First wireless module

142‧‧‧Second wireless module

151‧‧‧First light source

152‧‧‧second light source

17‧‧‧Image capture device

18‧‧‧ lens

19‧‧‧Wireless transmitter

Claims (9)

An image type multi-axis machine tool calibration system is provided with a sensing head, a standard ball group and a signal processing group, wherein: the sensing head is provided with a plurality of sensing groups, and the sensing group is provided with a wireless a module and a light source, wherein the wireless module is provided with a wireless transmitter and an image capture device, the light source provides a light output of sufficient intensity to enable the image capture device to clearly identify the object and capture the image; The ball set has a fixed seat, a support rod, a standard ball and a magnetic seat. The standard ball is fixed on the support rod, and the support rod is fixed on the fixed seat and the standard ball is inserted into the ball. In the measurement range of the sensing group of the sensing head, the standard ball material may be metal, plastic, ore; and the signal processing group is connected to the sensing head and provided with a wireless transceiver, the wireless transceiver and the wireless transceiver The wireless transmitters of the sensing group are connected to receive signals output by the wireless transmitters for program operation and analysis processing. The image type multi-axis machine tool calibration system of claim 1, wherein the sensing group can be two sets of surface image capturing devices or three sets of line image capturing devices, and providing sufficient light source intensity to be tested. Image recognition and transmission of the image to the signal processing group via a wireless transmitter. The image type multi-axis machine tool calibration system of claim 1, wherein the signal processing group is a computer. The image type multi-axis machine tool calibration system of claim 1, wherein the signal processing group is a single wafer. The invention relates to an image multi-axis machine tool calibration method, which comprises the following steps: installation step: combining a sensing head and a standard ball group between a spindle and a working platform of a multi-axis tool machine to be tested, so as to be located a standard ball on a support rod is disposed in the measurement space of the sensing head and located between the measurement ranges of the two sensing groups; The detecting step: by moving the X-axis and the Y-axis of the multi-axis machine tool to be tested, the light output of the light source enables each image picker to recognize the standard sphere, and the generated image signal is correspondingly The wireless transmitter and the wireless transceiver are transmitted to the signal processing group, and then the position of the center of the sphere is calculated and analyzed, and the image signals captured by the two wireless modules are processed, and the sensing signal of one of the wireless modules is processed. The offset of the Y-axis and the Z-axis can be measured, and the sensing signal of the other wireless module can measure the offset of the X-axis and the Z-axis; and the detection method: input the X-type machine tool to be tested, The Y coordinate, by the difference between the center position of the standard ball and the input coordinate position, and the error value of the multi-axis machine tool to be tested, and converting it into a compensation value wireless signal corresponding to the error value, the compensation value The signal is transmitted to the controller of the multi-axis machine tool to be tested, via which an automated error compensation can be performed for the multi-axis machine tool to be tested. The image type multi-axis machine tool calibration method of claim 5, wherein the sensing head is mounted by: locating the sensing head with a fixed end as a reference, and the standard ball group fixing a moving end to be located on the supporting rod The standard sphere is disposed in the measurement space of the sensing head and is located between the measurement ranges of the two sensing groups, the fixed end may be a machine tool spindle, etc.; the mobile end may be a machine tool working platform or the like. The image type multi-axis machine tool calibration method of claim 5, wherein the sensor head is mounted by: locating a sensing head with a moving end, and the standard ball group is fixed with a fixed end as a reference, so as to be located on the support rod The standard sphere is disposed in the measurement space of the sensing head and is located between the measurement ranges of the two sensing groups, the fixed end may be a machine tool spindle, etc.; the mobile end may be a machine tool working platform or the like. The image type multi-axis machine tool calibration method according to claim 6 or 7, wherein the detecting method is to sense a change in the three-dimensional direction (X, Y, Z) position of the center of the standard sphere through a sensing group. The image type multi-axis machine tool calibration method of claim 8, wherein the tool machine error value is set on the multi-axis machine tool to be tested by the sensing group, and the multi-axis machine tool to be tested is input to the detection path. The diameter of the center of the standard ball is sensed by the sensing group, which is different from the position of the input coordinate of the multi-axis machine tool. The position of the multi-axis tool machine in each direction of X, Y and Z can be obtained from the position difference between the two. error.