TW200842320A - One optoelectronic 6 degree of freedom measurement system based multi-reflection principle - Google Patents

Abstract

This patent comprises three 2 dimensional position sensing detector (2D PSD), one laser tower which contain some laser source and nine mirrors. The laser tower is placed on the measurement target and three 2D PSD was placed on specific position by the system fixture. Then the three PSD can get three laser rays from the laser tower. Before laser ray arrive the 2D PSD, the laser ray was reflected many time during the three mirrors. The accuracy of this patent can be better by increased times of reflection. This patent obtains the signal of 2D PSD by using the personal computer and Analog/ Digital converter card. The 6 degree of freedom (6-DOF) variation of measurement target can be obtained through calculating the signals of three 2D PSDs. The patent can be applied to 6-DOF measurement in micro-stage and rotary part.

Description

200842320 IX. Description of the invention: [Technical field of the invention] The present invention relates to a photoelectric six-free measurement system established by the principle of multiple reflection, in particular to a photoelectric non-contact measurement system, using a daily guard It is not affected by electromagnetic %, no probe wear, and it is easy to set up an optical measurement system that measures the error of six degrees of freedom of the object to be tested. [Prior Art] ® Most commonly used six-gauge metrology systems on the market are built with laser interferometers or a video system, which is quite expensive, but its accuracy is not high. Mostly used in the assembly or surface measurement of large-scale machines, such as eight cars, aircraft and ships. These measurement techniques are not suitable for multi-degree of freedom detection of micro-motion flats. Due to the small working range and the heavy load and light weight of the micro-motion platform, the current commercial products are not suitable due to the weight of the measurement system or the large volume. At present, most of the micro-motion platforms use multiple sets of electric-capacitor probes or multiple sets of strain gauges, but both probes have a single: free measurement capability. To construct a six-free measurement system, multiple sets of probes must be used. Master, and there will be problems with probe placement and cost. In recent years, some studies have used a reflective grating to establish a six-free measurement system that can be applied to a micro-motion platform. The measurement range is too small (linear measurement range < i mm, angle (four) degrees). At the same time, the 360 degree correction of the suspected rotating parts mostly uses the laser interferometer 4 to automatically align the sight gauge, but the laser interferometer can only provide the angular positioning correction. The automatic collimator can provide the 200842320 angular positioning and the tilt correction. . Both the laser interferometer and the automatic collimator are unable to provide a six-free measurement function, and the eccentricity and partial degree of freedom error of the rotating member cannot be detected. The laser interferometer is currently the most accurate commercial measurement system, but its price is high, the installation is troublesome, and a single measurement can only measure a single error. The automatic collimator has the advantage of being lower than the laser interferometer, easy to set up, and capable of measuring two axial angles in a single pass, but its accuracy is not as good as that of a laser interferometer. The laser interferometer has an angular measurement accuracy of 0.05 arc sec and an automatic collimator with an accuracy of approximately 0.5 to 1 ® arc sec. However, neither of these systems can detect the complete six-degree-of-freedom of the rotating part. i In the development of photoelectric measurement systems for nearly 30 years, many people use polarization interference technology to establish photoelectric angle measurement systems, but polarization interference technology has the same high cost and single measurement as laser interferometers. Energy measures one-dimensional angle changes. In addition to polarization interference, some studies have used techniques such as lenses, gratings, or interference fringes to improve the system accuracy and sensitivity of photoelectric measurement systems. However, most of these m- studies are only the development of a multi-free measurement system that can replace the automatic collimator, and cannot be applied to the 360 degree correction of the rotating parts.发明 | SUMMARY OF THE INVENTION The object of the present invention is to provide a photoelectric six-degree-of-freedom i measurement system that can simultaneously measure six free j-degree changes of a test object by using multiple reflection principles. |

I j The second object of the present invention is to provide a photoelectric six-self system which can be applied to a micro-motion flat | 200842320. The photoelectric six-self system established by the multi-reflection principle by measuring the degree of freedom detection. Another object of the present invention is to provide a photoelectric six-free measurement system that can be applied to the reshaping of the positioning performance of the rotating shaft, the rotary table, and the like, or the positioning measurement. A further object of the present invention is to provide a photoelectric six-free metrology system that can be used to perform 360-degree calibration and measurement of a rotating member using the principle of multiple reflection. The photoelectric six-free measurement system can be realized by the principle of multiple reflection, which can be achieved by the principle of multiple reflection, which is composed of a laser tower capable of placing multiple laser light sources, three Ϊ one-dimensional position sensors and nine sides. Composed of mirrors. The invention places the laser tower I on the object to be tested, and places three two-dimensional position sensors and nine-sided mirrors in a specific position by the clamp, so that three two-dimensional position sensors It is acceptable to receive laser light from three of the laser sources in the Ray Tower. The laser emitted by the laser tower; the light is reflected multiple times between the mirrors before reaching the individual two-dimensional position sensor. i can increase the accuracy of the system of the present invention by increasing the number of reflections of the laser light. The present invention obtains three degrees of freedom change of the object to be tested through the counterfeit by using a personal computer and an analog/digital signal conversion card to capture three two-position sensors. The invention can be applied to a six-free metric measurement of a micro-motion platform and a 360-degree six-free friction correction of the rotating member. i

[Embodiment] I Please refer to FIG. 1 , the 200842320 photoelectric six-free measurement system established by the invention using the multi-reflection principle, mainly includes: a laser tower 3 capable of placing multiple laser light sources 2 The three-dimensional position sensors 41 to 43 and the nine-sided mirrors 51 to 59, wherein the laser light source 2 can adopt visible light, microwave, infrared light, ultraviolet light, X-ray, and end-measurement environment. The need for precision and replacement can be applied to the relative distance measurement; wherein the two-dimensional position sensors 41 to 43 can be optical sensors, CCD image sensors, CMOS image sensors or The sensor that measures the two-dimensional signal replaces it. The invention places the laser tower 3 on the object 1 to be tested, and three three-dimensional position sensing benefits 41~43, and the nine-sided mirrors 51~5 9 by the system clamping tool 61~β 3 placed in a specific position, so that three two-dimensional position sensors 41 ~ 43 can be accepted.

I Laser light of three laser light sources 2 of the laser tower 3; the lightning light emitted by the laser tower 3 before reaching the individual two-dimensional position sensors 41 to 43 will be more between the mirrors! The reflection can increase the system brightness of the present invention by increasing the number of reflections of the laser light, and then pass through the signals of the three-dimensional position sensors 41 to 43 of the personal computer and the analog/digital signal conversion card. Calculate the object to be tested [s: six degrees of freedom change. | t

The general definition of the object error is shown in Figure 2. Three linear positioning errors (heart (8), ~(8), ^(8)), two angle yaw errors & (8), ~ (9) ^ an angular positioning error 〇 9) rotation 6 degrees of freedom error for the axis. The system architecture of the present invention comprises a tower 3 composed of a plurality of laser sources 2 and a signal receiving end composed of a number of mirrors and two-dimensional position sensors 41 to 43. Show. The present invention places the laser tower 3 on which the plurality of laser light sources 2 are placed on the object to be tested 1, and fixes the three two-dimensional position sensors 41 to 43 and the nine-sided mirrors 51 to 59 in the system clamp. The fixture has βΐ~β3. The three mirrors 51 to 53 and the two-dimensional position sensor 41 are formed into a subsystem, and are respectively placed at specific positions of the system fixture 61 to receive the laser light source of the laser tower 3. Next, the output lines of the two-dimensional position sensors 41 to 43 are connected to the position sensor signal processor, and the output line of the position sensor signal processor is connected to the analog signal inserted in the personal electric sentence. / digital signal conversion card. After the erection is completed, the position of the light spot on the three two-dimensional position sensors 41 to 43 can be recorded by the personal computer program to calculate the error variation of the six degrees of freedom. Through the multiple reflection of the laser beam, the system's spiritual failure and measurement accuracy can be effectively improved. Taking a system that has undergone three reflections as an example (as shown in Figure 3), when the system only undergoes one reflection, the difference between the angle of incidence of the reflection 铙53 before and after the angle change is: !

I

Aj = L{sm0l - sin^2) ! When the beam passes through the second reflection, the difference between the position of the incident point of the mirror 52 before and after the angle change is: : ; Δ2 = Aj + L(sin^ - Sin^2) = 2Aj i The position at which the last light falls on the position sensor 41 can be written as follows: i △3 = Δ2 + dsin(6>2 - q) = 2Δ! + dsin(<92 - ( 3⁄4) 200842320 It can be seen from the above formula that whenever the beam is reflected once, the position difference before the angle change and the angle change will increase by - times, @ this is achieved by simply reflecting the material to improve the sensitivity and measurement accuracy of the system. Figure 4 (a) to Figure 4 (c) are the surface light path between the various subsystems of the present invention and the laser tower 3, in which the laser tower 2 is provided with 12 sets of laser light sources 2, The number of laser light sources 2 on the tower 3 depends on the number of samples required for the 360 degree correction of the turntable. For example, it can only be applied to the six-free measurement of the micro-motion platform. As long as three sets of laser light sources 2 can meet the system requirements. a) for the plane light diagram of subsystem one and laser tower 3,

Figure 4 (6) is a planar optical path diagram of subsystem 2 and laser tower 3, and Figure 4 is a planar optical path diagram of subsystem 2 and laser tower 3. I The three-degree-of-freedom error of the three subsystems of the present invention and the laser tower 3 change the position of the light spot on the three position sensors as follows: i _ five (') is the delay axis of the object to be tested 1 When the direction is moved, the position of the two-dimensional position L detector μ laser spot does not have any deviation, and the position of the two-dimensional position sensor d laser light is shifted to the left 'two-dimensional position sense (four) 43 laser spot position is not Any offset; ; Figure (b) is the object to be tested! When moving in the γ-axis direction, the two-dimensional position sensor emits light (four) position on the moving, the two-dimensional position sense (four) 42 thunder (four) points have a position of one of the # _ dimensional position sensor 43 laser spot position toward Left movement; : Two-dimensional position sensor Figure 5 (c) When the object to be tested 1 moves in the direction of the axis, the position of the 4,423 laser spot is moved to the right, and the position of the laser spot of the two-dimensional position sensor 42 When moving up, the position of the laser spot of the two-dimensional position sensor 43 moves upward; _ five (d) is the position of the laser spot of the two-dimensional position sensor when the object 1 is rotated about the X-axis direction The offset, the two-dimensional position sensor is violent (4) The position of the 2 moves upwards. The position of the laser spot of the two-dimensional position sensor 43 is not offset by the dance; Figure 5 (e) is the winding of the object to be tested When the γ-axis direction rotates, the position of the laser light material of the two-dimensional position sensor 41 moves to the left. The position of the laser-first point of the two-dimensional position detector 42 does not have any offset, and the position of the two-dimensional position detector 43 (four) Position 丨 moves upwards; 丨 Figure 5 (1) is when the object 1 is rotated about the Z-axis, the two-dimensional complex sensor 4i field light When the position moves upward, the position of the laser spot of the two-dimensional position sensor moves to the right, and the position of the laser spot of the two-dimensional position sensor 43 moves to the left; because of the spot on the one-dimensional position sensor 4 The change is different for the six-degree-of-freedom change, so the six-degree-of-freedom change of the object to be tested can be calculated by calculating the pupil change on the three-dimensional position sensor 4丨. ♦ > } (1) System architecture and action description:

I The system architecture of the present invention is shown in the figure - the erection mode and the action method are as follows:

I i (a) Fixing a plurality of laser light sources 2 on the laser tower 3; 200842320 (b) erecting the laser tower 3 on the object to be tested 1; (c) feeling the two-dimensional position The detector 41, the mirror 51, the mirror 52 and the mirror 53 are fixed on the system fixture 61; (d) The two-dimensional position sensor 42, the mirror 54, the mirror 55 and the mirror 56 are fixed in the system (e) Fixing the two-dimensional position sensor 43, the mirror 57, the mirror 58 and the mirror 59 on the system fixture 63; ^ (f) sensing three three-dimensional positions 4, 43 signal line connection 'to position|sense signal processor; 丨| (g) position sensor signal processor output, connect to the plug-in! analog signal / digital signal conversion on a personal computer The card converts the analog signal of the position sensor signal processor into a digital signal for personal power!

Subsequent storage of the brain; I _ After the erection and connection of the system is completed, when the object 1 has an arbitrary degree of freedom of movement, the laser spot on the two-dimensional position sensors 41 to 43 will have a corresponding change. By analyzing the change in the position of the light spot on the one-dimensional position sensors 41 to 43, the error variation of the six degrees of freedom of the object to be tested 1 can be obtained. The measurement system established by the present invention must correct the two-dimensional position sensor and the overall system before performing the actual measurement. j (2) Two-dimensional position sensor correction: 12 200842320 Two-dimensional position sensors 41 to 43 must be corrected before being used for measurement, as shown in Figure 6. The two-dimensional position sensor 41 is placed on the position sensor to clamp the horse 9, and then placed on the linear micro-motion platform 12, on which the laser light source 2 is driven in, and then the mirror group 10 and the laser interferometer 11 are mounted. The laser interferometer 11 can measure the amount of movement of the linear micro-motion stage 12. Finally, the linear micro-motion platform 12 is moved back and forth several times at a fixed distance, and the two-dimensional position sensor 41, the number and the reading value of the laser interferometer 11 are synchronously captured, and the data acquired by the process is passed. After the least square method is calculated, the calibration curve of the set of two-dimensional position sensors 41 can be obtained. The above correction process is shown in Figure 7(a). The correction of the two-dimensional position sensor 41 is divided into an X-axis correction and a Y-axis correction twice.

I When the X-axis correction is performed, the linear micro-motion platform 12 moves in the following way: Let the linearity: the micro-motion

The moving direction of the I stage 12 is parallel to the X-axis of the two-dimensional position sensor 41, and then moves back and forth several times at a fixed distance within the working range of the two-dimensional position sensor 41; and the correction of the Y-axis is two-dimensional After the position sensor 41 turns 90 degrees, let the linear micro-motion

The movement direction of the I stage 12 is parallel to the Y-axis of the two-dimensional position sensor 41, and then the line is made

The I-type micro-motion platform 12 is fixed at a distance of I in the working range of the two-dimensional position sensor 41.

I Move back and forth several times. The above correction process is shown in Figure 7(b). The X-axis and Y-axis correction curves of the two-dimensional position sensor 41 can be obtained by calculating the data acquired by the upper _ two moving processes. Through the above two-dimensional position sensor calibration process, ie

• I can get the relationship between the position sensor signal and the position of the spot on the position sensor. Because of this, the present invention can obtain the position of the position sensor illuminator 13 200842320 by simply taking the signal of the position sensor. (III) Laser tower calibration: Since the position of each laser light source 2 of the laser tower 3 affects the uncertainty of the overall system, the laser tower 3 of the present invention must be corrected before actual use. . The calibration of the laser tower 3 is shown in the figure, and the calibration process is shown in Figure 9. First, place the laser tower 3 on a zero-returned turntable? Above, the standard multi-faceted cymbal 14 is placed on the laser tower 3, and then erected from the 'the collimator 13 to align it with any _ plane mirror of the multi-faceted cymbal 14, and finally the position I is set. The device 4 43 allows the three *sensors 41 to 43 to be normally accepted: a laser beam. At the beginning of the calibration, the readings of the personal computer _ group position sensor 及 and the reading of the automatic collimator 13 are first passed. Then, the turntable 7 is rotated by a fixed angle, and then the reading value of the set of position sensors 42 and the master value of the automatic collimator 13 are recorded through the personal computer. By repeating the above recording and rotation process and calculating the reading values of the position sensors 41 to 43 of each record of the present invention, the error of the turntable 7 and the error of the present invention can be obtained by the automatic collimator 13. By comparing the automatic collimator with the measurement result of the present invention, the error of the laser tower 3 can be obtained. Through the above-mentioned calibration process, when the present invention is used to measure or correct the turntable 7 in the future, as long as the error of the laser tower 3 is compensated, an accurate six degrees of freedom of the object to be tested can be obtained. The angle of each turn of the turntable 7 depends on the number of laser light sources 2 of the laser tower 3. The number of faces of the standard multi-faceted prism 14 is also determined by the number of laser light sources 2 of the laser tower 3 200842320. If the laser tower 2 has 12 laser light sources 2, the angle of rotation of the turntable 7 is 30 degrees each time, and the number of faces of the standard multi-faceted cymbal 14 must be a multiple of 12. (IV) Turntable six-free metric measurement The erection mode of the six-free metric measurement or correction of the turntable is shown in Figure 1. The calibration process is shown in Figure 10. First, the laser tower 3 is placed on a zero-returned turntable 7, and then the position sensors 41 to 43 are erected so that the three position sensors 41 to 43 can normally receive the laser beam. At the beginning of the measurement, the readings of a set of position sensors 41 are first recorded through the personal computer. Next, the turntable 7 is rotated by a fixed angle: and then the reading of a set of position sensors 41 is recorded through a personal computer. Through the heavy | complex, above, recorded and rotated process, and calculate the position of each position of the invention 'tester $ 1 ~ ', and subtract the error of the laser tower 3, you can get the turntable 7 "difference. The angle at which each turntable 7 is rotated depends on the number of laser light sources 2 of the f-shooting tower 3. If the laser tower 3 has 12 laser light sources 2, the angle of rotation of each of the turntables 7 is 30 degrees. (5) The six-degree-of-freedom motion measurement of the fretting platform and the six-degree-of-freedom vibration amount, then 1, the dynamic level/, the degree of freedom motion measurement or the six-degree-of-freedom vibration measurement frame, as shown in the figure. First, the laser tower 3 is placed on a phase i of the vibrating body of the platform i to be tested, and then the position sensor (6) 3 is mounted, and the three sensors 4 to 43 can normally receive the laser. beam. When measuring, the soul is over 15 200842320 The reading value of the position sensor 41~43 is not recorded, and the real-time situation of the object to be tested can be obtained through the instant calculator. By performing the Fourier transform on the measurement result of the personal computer := record, the spectrum of the vibration of one degree of freedom to be obtained can be obtained. If the system is used for static measurement, just let the personal computer record the two-dimensional position sensors 41 to 43 after the end of the test object, and calculate the six freedoms to get the six freedoms after the exercise. The change in degree. As stated on the silk, this case is not only innovative in terms of space type, but also: it can enhance the above-mentioned multiple functions compared with the conventional articles, and should fully comply with the new law of laissez-faire and progressiveness - the invention patent requirements, : / 疋 朴 朴 局 局 局 局 局 局 局 局 局 局 局 局 局 局 局 局 局 局 局 局 局[solid simple description];

I Figure - is an architectural diagram of the photoelectric U-free metrology measurement system established by the multi-reflection principle of the present invention;

I Figure 1 is a schematic diagram of the six-degree-of-freedom error; Figure 2 is a schematic diagram of the effect of reflection on the position sensor reading; i Figure 4 is the plane light path diagram of the laser tower and position sensor; i W is the respective motion Causes the position of the light spot on the two-dimensional position sensor to change _ ·, ! • Figure 6 is the calibration structure of the two-dimensional position sensor; 'Figure 7 (a), Figure 7 (b) is the position sensor calibration process Figure; i 16 200842320 Figure 8 is a schematic diagram of the laser tower calibration erection; Figure 9 is the laser tower calibration flow chart, and Figure 10 is the turntable six free measurement test operation flow [main component symbol description] 1 test object 2 mine Light source 3 Laser tower 41 ~ 43 Position sensor 51 ~ 59 Mirror 61 ~ 63 System fixture. 7 Turntable 9 Position sensor fixture 10 Mirror group 11 Laser interferometer 12 Linear fine adjustment platform 13 Automatic collimator 14 multi-faceted 稜鏡 17

Claims (1)

200842320 X. Patent application scope; 1. A photoelectric six-free metrology system established by the principle of multiple reflections includes: ί multi-channel laser source, fixed on the laser tower, and the laser source is provided a laser beam of the same wavelength; a two-position sensor that picks up the position of the laser beam; a nine-mirror that provides multiple reflections between the mirrors before the laser beam reaches the individual position sensor to increase the thunder The number of reflections of the beam; and the two-system fixture, which provides a position sensor and a three-mirror fixation. 2, as described in the first paragraph of the patent application, the photoelectric six-free measurement system established by the principle of multiple reflection, wherein the laser source can adopt visible light, microwave, infrared light, ultraviolet light, X-ray, and the end It can be replaced according to the required and precision requirements of the measurement environment and can be applied to the relative distance measurement. 3) A photoelectric six-free metrology system established by the principle of multiple reflection as described in the first paragraph of the patent application, wherein the position sensor,! It is a two-dimensional position sensor. 4. A photoelectric six-free metrology measurement system established by using multiple reflection primitives as described in claim 3, wherein the two-dimensional position sensor can be optically sensed, CCD image sensor A CMOS image sensor or a sensor that can measure a two-dimensional signal instead. 5, a photoelectric six-free measurement system established by using multiple reflection reproducibility as described in claim 1, further comprising a signal processor for converting the output signal of the position sensor to voltage by 200842320 Signal. The photoelectric six-free measurement system established by the multi-reflection principle according to the fourth aspect of the patent application includes a analog/digital signal conversion card, and converts the signal processor output signal of the position sensor into Digital signal. 7. The photoelectric six-free measurement system established by the multi-reflection principle as described in the U.S. Patent Application Serial No. U 6 further includes a computer for storing the digital signal converted by the analog/digital §fl conversion card. Among the personal computers. | A photoelectric six-free metrology measurement system established by using multiple reflection primitives as described in claim 1, wherein the multi-channel laser light source laser tower is placed on the object to be tested, by playing On the position sensor, the laser source of the laser I tower, by analyzing the position of the spot on the final position sensor / obtains six degrees of freedom of the object to be tested. Θβ is a photoelectric six-degree-of-freedom Dong 糸 system established by the principle of multiple reflection as described in the first paragraph of the patent application. Three of the position sensors can receive lasers of three laser light sources of the laser tower. beam. 1 〇. A photoelectric six-free metrology measurement system established by the principle of multiple reflection according to claim 1, wherein the number of *shooting light sources on the laser tower depends on the sampling required for the 360 degree correction of the turntable number. '11. A photoelectric six-free metrology system of 200842320, which is established by using multiple reflection primitives, as described in claim 1, wherein the laser beam is reflected once, and the angle is changed before and after the angle is changed. The position difference will be doubled and the system accuracy is therefore doubled. 12· As set forth in claim 1 of the patent application, a multi-reflection principle is established The photoelectric six-free measurement system, wherein the correction of the position sensor is divided into an X-axis correction and a γ-clock correction twice, and when performing the χ-axis correction, the linear micro-motion platform moves in a way: Let the linear micro-motion + the movement of the stage The direction is parallel to the X-axis of the position sensing, and then the linear micro-motion platform is moved back and forth several times at regular intervals within the working range of the position sensor. The number of private movements is back-to-person, and the correction of the γ-axis is to make the position sensor rotate and let the line! The moving direction of the micro-motion platform is parallel to the axis of the position sensor, and the sensor is within the working range of the sensor. Fixed distance 20