TWI401420B - A device for measuring the multi - axis error of the pick - and - place mechanism - Google Patents

Description

Device for detecting multi-axis error of pick-and-place mechanism by using split beam

The invention relates to a device for applying multi-axis error of a split beam detecting pick-and-place mechanism, which adopts an optical non-contact detecting mode to achieve the high precision requirement of obtaining the error of the pick-and-place mechanism as an innovative technology.

For example, the wafer packaging machine generally used has an accuracy of about 10 μm. If the speed of the pick-and-place mechanism is to be increased or the precision of the pick-and-place mechanism is improved, the pick-and-place mechanism has a great influence. It may be that the steel of the pick-and-place mechanism is insufficient. If the steel is to be improved, the pick-and-place mechanism may be too heavy, and the movement when the clip is taken or placed may also have insufficient precision. The measuring instruments currently used are not expensive enough.

In addition, if the contact measurement is used, the reaction force generated by the pick-and-place mechanism touching the object during the pick-and-place action may cause the measurement result to be inaccurate.

At present, the industry generally uses high-speed cameras to measure the error of the pick-and-place mechanism, but the problems of this high-speed camera are as follows:

(1) Insufficient accuracy: When using a high-speed camera for measurement, the camera is shot outside the machine, but when the machine is operating, vibration will occur, so the camera is unclear when the pick-and-place mechanism is relative to the ground. The vibration, or the vibration of the pick-and-place mechanism relative to the object;

(2) Less measurement data: the high-speed camera can draw too little data per second, and its accuracy is poor;

(3) High cost: the price of high-speed cameras is high, and the price is generally more than one million;

(4) Insufficient measurement signal: The image captured by the high-speed camera is the error of the Z-axis and the Y-axis, and the original requirement is to measure the error of the X-axis, the Y-axis, the Z-axis, θ _x and θ _y .

Therefore, in view of the above-mentioned technology of the pick-and-place mechanism, the inventor of the present case has in-depth discussion on the problems that cannot be solved. It is the improvement and innovation of the thinking, and after years of painstaking research, he finally succeeded in research and development to complete an application of sub-beam detection and handling. The multi-axis error device of the mechanism uses the non-contact measurement of the sensor and the light source, so that the measurement result is more accurate without worrying about the reaction force.

The object of the present invention is to provide a device for detecting multi-axis error of a pick-and-place mechanism by using a split beam, which is suitable for a pinch (suction) mechanism of a wafer packaging machine, a robot arm, etc., and can simultaneously measure a pick-and-place mechanism or a transport arm mechanism. Its multiple degrees of freedom error.

A second object of the present invention is to provide a low-cost, high-accuracy, small-volume, and portable device for detecting multi-axis errors of a sub-beam detection pick-and-place mechanism.

Another object of the present invention is to provide a device for arranging a simple and fast detection multi-axis error of a sub-beam detecting pick-and-place mechanism.

Another object of the present invention is to provide a device for detecting multi-axis error of a pick-and-place mechanism by using a split beam, which has a sensor for capturing data data at a high frequency, so as to effectively improve the problem of insufficient measurement accuracy.

A device for detecting a multi-axis error of a pick-and-place mechanism by using a beam splitter, which includes the following objects, including:

The invention comprises a light source splitting unit, which comprises splitting a light beam of a light source into a reflected light beam and a penetrating light beam;

The first sensing unit is configured to use two independent sensors for the beam emitted by the beam splitter to be projected thereon, wherein the first sensing unit is further provided with a first sensor and a second sensor. The first sensor receives the reflected light emitted by the beam splitter, and the second sensor receives the transmitted light emitted by the beam splitter;

The second sensing unit uses two independent sensors for the light beam emitted by the beam splitter to be projected thereon, and the second sensing unit is further provided with a third sensor and a fourth sensor, The third sensor receives the reflected light from the beam splitter, and the fourth sensor receives the transmitted light from the beam splitter.

a signal processing unit is coupled to the first sensing unit and the second sensing unit, and the signal processing unit receives the output signal of the sensor, and performs arithmetic processing and analysis detection to convert the system into a system processing. Signal.

The above-mentioned measured processing signals can be obtained by the user using the Fast Fourier Transform (FFT) calculation according to the requirements, and then the vibration frequency of the pick-and-place mechanism can be obtained.

Referring to FIG. 1 to FIG. 3 , the present invention provides a device for detecting multi-axis error of a pick-and-place mechanism by using a split beam, which mainly includes: a light source splitting unit (2), a first sensing unit and a second sensing. The unit is composed of. When the pick-and-place mechanism (1) is applied to an integrated circuit or wafer, the associated axis of the pick-and-place mechanism (1) further includes a first axis position (11) or a second axis position (12). When the pick-and-place mechanism (1) is applied to a mechatronic device (such as a multi-joint robot) that performs a specific operation, the relevant axis of the pick-and-place mechanism (1) further includes a first axis position, a second axis position, a third axis position, or more axis positions (eg, a fourth axis position, or a fourth axis position and a fifth axis position, or a fourth axis position and a fifth axis position and a sixth axis position), which is familiar to the The craftsperson can know, but not for restrictions;

The following is a description of the two-axis pick-and-place mechanism (such as a wafer packaging mechanism) applied to an integrated circuit or a wafer, but is not intended to limit:

The light source splitting unit (2) comprises a beam (211) of a light source (21) incident on the beam splitter (22), and splits into a reflected beam (221) and a transmitted beam (222); wherein the light source (21) It is one of a collimated light source or a focusing light source; and the light source (21) can also be used for the effects of absolute distance measurement by using visible light, infrared light, ultraviolet light, X-ray, and invisible light;

The first sensing unit uses two independent sensors for the light beam emitted by the beam splitter (22) to be projected thereon, wherein the first sensing unit is further provided with a first sensor (31) and a second sensor (32); the first sensor (31) is a reflected light (221) emitted by the receiving beam splitter (22), and also converts the incident position of the reflected light (221) into an output signal; The second sensor (32) is configured to receive the transmitted light (222) emitted by the beam splitter (22), and also converts the incident position of the transmitted light (222) into an output signal;

The second sensing unit uses two independent sensors for the light beam emitted by the beam splitter (22) to be projected thereon, and the second sensing unit is further provided with a third sensor (41) and a fourth sensor (42); the third sensor (41) is a reflected light (221) emitted by the receiving beam splitter (22), and also converts the incident position of the reflected light (221) into an output signal; The fourth sensor (42) is a transmitted light (222) emitted by the receiving beam splitter (22), and also converts the incident position of the transmitted light (222) into an output signal.

Referring to FIG. 2, a device for detecting positioning and angular error of a single light source by using a single light source, further comprising: a light source splitting unit (2), a lens (5), a first sensing unit, and a second a sensing unit and a signal processing unit (not shown); wherein the lens (5) is disposed in front of the light source (21) and on the optical path of the light beam (211) to the light beam (211) Corrected to collimate light and illuminate the beam splitter (22);

The signal processing unit is coupled to the first sensing unit and the second sensing unit, and the signal processing unit receives the output signal of the sensor, and performs arithmetic processing and analysis and detection to convert the system into processing. Signal.

Next, when the present invention is applied to the pick-and-place mechanism (1), the pick-and-place mechanism (1) has a first shaft (11) (ie, an object clip (suction) take-up end) and a second shaft (12) (ie, An object placement end), wherein the first sensing unit is disposed at a position of a first axis (11) that receives a beam splitting beam, and the second sensing unit is configured to receive a second axis of a beam splitting beam (12) At the position, when the above measurement principle is that the pick-and-place mechanism (1) performs the action of clamping (sucking) or placing, a slight displacement in the left-right direction may occur due to the influence of the X-axis positioning error, which may be affected by the Y-axis positioning error. The slight displacement in the front-rear direction causes a slight displacement in the up-and-down direction due to the influence of the Z-axis moving distance, and a slight rotation along the X-axis and the Y-axis occurs due to the influence of the angular error of θ _x and θ _y ;

Further, when the light source (21) moves, the first sensor (31) and the second sensor (32) disposed at the position of the first axis (11) receive the reflected light (221) and the light after the splitting. Transmitting (222), while the first sensor (31) detects the Z-axis moving distance of the pick-and-place mechanism (1) on the first axis (11) and the θ _x angle error; and the second sensor ( 32) detecting an X-axis positioning error, a Y-axis positioning error, or an X-axis positioning error and a Y-axis positioning error of the pick-and-place mechanism (1) on the first axis (11);

If the pick-and-place mechanism (1) is clamped or placed at the position of the second shaft (12), the third sensor (41) and the fourth sensor disposed at the position of the second shaft (12) The device (42) receives the reflected light (221) and the transmitted light (222) after the splitting, and the third sensor (41) detects the pick-and-place mechanism (1) on the second axis (12). The axis movement distance is in error with the θ _x angle; and the fourth sensor (42) detects the X-axis positioning error, the Y-axis positioning error, or the X-axis positioning of the pick-and-place mechanism (1) on the second axis (12) Error and Y-axis positioning error; thereafter, the first sensor (31) and the second sensor (32), or the third sensor (41) and the fourth sensor are received by the signal processing unit ( After the output signal of 42), the arithmetic processing is performed to convert the output signal of the sensor into a system processing signal for the user to read or interpret.

The present invention can derive errors in the X-axis, the Y-axis, the Z-axis, θ _{x ,} and θ _y via the following formula:

It is assumed that the two axes of the second sensor (32) are V _Ax and V _Ay , and the two axes of the first sensor ( 31 ) are V _Bz and V _By , and the signals measured by V _Ax are X-axis positioning. The error between the error and θ _y , the signal measured by V _Ay is the Y-axis positioning error and the θ _x angle error, and the signal measured by V _Bz is the Z-axis moving distance, the X-axis positioning error and the θ _y angle error. The signal measured by V _By is the Y-axis positioning error and the θ _x angle error. Since the present invention moves the light source (21) and the beam splitter (22) simultaneously, V _By will measure the Z-axis moving distance. Since the clip (suction) take-up end and the placement end are symmetrical, the following derivation process clamp (suction) take-up end and the placement end are applicable, and then are deduced by the following formula.

V _Ax =X+θ _y , V _Ay =Y+θ _x , V _Bz =X+θ _y , V _By =Z+θ _x , where θ _x and θ _y are multiplied by a factor due to the difference in distance between the sensor and the beam splitter (22), So here are the four formulas:

V _Ax =X+eθ _y (1)

V _Ay =Y+eθ _x (2)

V _Bz =X+fθ _y (3)

V _By =Z+fθ _x (4)

Substituting equation (1) X=V _Ax -eθ _y into equation (3) gives V _Bz =V _Ax -eθ _y +fθ _y after finishing:

θ _y =(V _Ax -V _Bz )/(e+f) (5)

Substituting equation (5) into equation (1) is obtained:

X=V _Ax -e(V _Ax -V _Bz )/(e+f) (6)

Using equation (2) Y=V _Ay -fθ _x into equation (4), V _By =V _Ay -eθ _x +hθ _{y is} obtained:

Substituting equation (7) into equation (2) is obtained:

The Z-axis moving distance can be obtained by substituting X and θ _y derived by equations (5) and (6) into V _Bz =X+fθ _y +Z:

V _Bz = X ten fθ _y ten Z (9)

Substituting equations (5) and (6) into equation (9) results in:

Wherein, when the pick-and-place mechanism (1) is clamped (sucked) or placed, an X-axis positioning error is generated, and an error generated by the light source (21) incident on the sensor causes the spot focused on the sensor to be as shown in the figure. Four is shown. Moreover, the Y-axis positioning error is generated when the pick-up mechanism is clamped or placed, and the error caused by the light source (21) incident on the sensor causes the spot focused on the sensor to be as shown in FIG. .

Therefore, the signal processing unit performs arithmetic processing, and the user can convert the processed signal into a Fast Fourier Transform (FFT) according to the demand, and then the vibration frequency of the pick-and-place mechanism (1) can be obtained. In this way, the invention can effectively achieve the substantial benefits such as low cost, high precision, small size, convenient carrying, simple erection and rapid detection.

Through the above, a device designed to detect the positioning and angular error of the pick-and-place mechanism (1) by using a single light source is specifically represented in the above detailed description, but the embodiment is not intended to be limited. The equivalents of the invention are intended to be included within the scope of the invention as claimed.

In summary, the present invention designs a device for detecting the positioning and angular error of the pick-and-place mechanism by using a single light source, which is not only innovative in the current industrial type, but also has a complete innovation in the overall structural features and technical applications, and no similar items are found. In order to be innovative and have the full value of the industry, it has already met the requirements of the invention patent. If you file an application according to law, you are requested to approve the invention patent, so that the invention can be used to benefit the broad masses of the society at an early date.

1. . . Pick and place mechanism

11. . . First axis

12. . . Second axis

2. . . Light source unit

twenty one. . . light source

211. . . beam

twenty two. . . Beam splitter

221. . . reflected light

222. . . Penetrating light

31. . . First sensor

32. . . Second sensor

41. . . Third sensor

42. . . Fourth sensor

5. . . lens

1 is a structural diagram of a measuring optical path of a device for detecting a multi-axis error of a split-beam detecting and pick-and-place mechanism according to the present invention;

2 is a schematic diagram showing the measurement of the collimating lens of the measuring optical path of the present invention;

Figure 3 is a schematic diagram showing the measurement of the front side structure of the measuring optical path of the present invention;

Figure 4 is a schematic diagram of the X-axis positioning error of the sensor of the present invention;

Figure 5 is a schematic diagram of the positioning error of the Y-axis of the sensor of the present invention.

1. . . Pick and place mechanism

11. . . First axis

12. . . Second axis

2. . . light source

twenty one. . . beam

twenty two. . . Beam splitter

3. . . First sensing unit

4. . . Second sensing unit

Claims (8)

The utility model relates to a device for detecting multi-axis error of a pick-and-place mechanism by using a partial beam, comprising: a light source splitting unit, which is configured to split a light beam of a light source into a beam splitter and split the light into two light beams; the first sensing unit is configured to receive at least one split light. At the first or second axis position of the beam, two separate sensors are used for the beam emitted by the beam splitter to be projected thereon, and behind it, the output signals of the respective sensor outputs are operated. a device for processing; a second sensing unit configured to receive at least one beam of light at a second axis or a first axis position, using two separate sensors for the beam emitted by the beam splitter to be projected onto the signal The processing unit is coupled to the first sensing unit and the second sensing unit. The signal processing unit receives the output signal of the sensor, and performs arithmetic processing and analysis detection to convert the signal into a system processing signal. The device of claim 1 , wherein the first sensing unit is further provided with a first sensor and a second sensor, the first The sensor receives the reflected light from the beam splitter of the light source splitting unit. The device of claim 1 , wherein the first sensing unit is further provided with a first sensor and a second sensor, the second The sensor senses the transmitted light emitted by the beam splitter of the light source splitting unit. The device of claim 1 , wherein the second sensing unit is further provided with a third sensor and a fourth sensor, the third The sensor receives the reflected light from the beam splitter of the light source splitting unit. The device of claim 1 , wherein the second sensing unit is further provided with a third sensor and a fourth sensor, the fourth The sensor receives the transmitted light from the beam splitter of the light source splitting unit. A device for detecting a multi-axis error of a pick-and-place mechanism by using a split beam as described in claim 1, 2 or 4 , wherein the first sensor or the third sensor senses a Z-axis moving distance and θ _x angle error. A device for detecting a multi-axis error of a pick-and-place mechanism by using a split beam as described in claim 1, 3 or 5 , wherein the second sensor or the fourth sensor senses an X-axis positioning error and Y-axis positioning error. An application of the items 1 The fraction of the light beam detecting means a multi-axis error mechanism to take place, which further comprises a lens, the lens system disposed in front of the light source and the optical path of the beam to the beam Corrected to collimated light and illuminated to the beam splitter of the source splitting unit.