Gantry taking and placing goods positioning device, gantry system and gantry transportation method

Abstract

The crane takes and puts the positioning device, the crane system and the crane transportation method, and the positioning device includes a first detection component and a second detection component; the first detection component includes a first sensor arranged on the crane and a first positioning sheet arranged on the equipment platform, and the first detection component is used for detecting whether the equipment platform is displaced and measuring the distance; the second detection component includes a second sensor arranged on the crane, a second positioning sheet arranged on the equipment platform and a third positioning sheet arranged on the top of the goods, and the second detection component is used for detecting whether there is an obstacle between the crane and the equipment platform and between the crane and the goods. The application can detect whether the equipment platform is displaced, dynamically adjust the taking and placing position parameters of the crane on the equipment platform, ensure the safety and stability of the crane, detect whether there is an obstacle between the equipment platform and the crane and between the crane and the goods, improve the safety production capacity and reduce the safety risk.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of wafer automatic handling system, and particularly relates to a crane taking and placing goods positioning device for wafer handling, a crane system and a crane transportation method. BACKGROUND

[0002] The crane system is very commonly used in wafer processing workshops. The crane system mainly comprises a crane and a track. The track is suspended and installed on the ceiling joist of a wafer production workshop. The crane can run along the track and move between different positions to realize transportation of goods. When the current crane system transports goods, the crane is positioned by scanning a two-dimensional code pasted on the track during the running process. When the crane scans the two-dimensional code bound to the target equipment platform during the movement along the track, the crane stops and communicates with the inductor of the target equipment platform. When it is confirmed that the conditions are met, the crane will execute the action of taking and placing goods. This positioning method only positions by scanning the two-dimensional code bound to the equipment platform. If the equipment platform where the wafer is placed is displaced, the crane cannot know the change of the position of the target equipment platform through the two-dimensional code on the track. The crane will still mechanically execute the action of stopping after scanning the two-dimensional code, communicating with the inductor to confirm that the conditions are met, and still executing the action of taking and placing goods according to the original position information, which has a safety hazard. SUMMARY

[0003] The application aims to provide a crane taking and placing goods positioning device which can reposition the position of the target equipment platform and dynamically adjust the taking and placing position parameters of the crane.

[0004] Another object of the application is to provide a crane system which can reposition the position of the target equipment platform and dynamically adjust the taking and placing position parameters of the crane when taking and placing goods.

[0005] Still another object of the application is to provide a crane transportation method which can reposition the position of the target equipment platform and dynamically adjust the taking and placing position parameters of the crane when taking and placing goods.

[0006] In order to achieve the above-mentioned first object, the application adopts the following technical solutions:

[0007] The crane taking and placing goods positioning device, the crane can grab goods from the equipment platform or place goods on the equipment platform, and comprises:

[0008] The first detection assembly and the second detection assembly;

[0009] The first detection assembly comprises a first inductor arranged on the crane and a first positioning sheet arranged on the equipment platform, and is used for detecting whether the equipment platform is displaced and measuring the distance;

[0010] The second detection assembly includes a second sensor arranged on the trolley, a second positioning sheet arranged on the equipment carrier, and a third positioning sheet arranged on the top of the goods, and is used for detecting whether there is an obstacle between the trolley and the equipment carrier and between the trolley and the goods.

[0011] The trolley taking and placing goods positioning device as described above, optionally, the first sensor is arranged at the front of the trolley, and the first sensor can emit a first light ray towards the equipment carrier, and the first light ray forms a light ray segment on the equipment carrier which is perpendicular to the advancing direction of the trolley; the distance measured by the first detection assembly includes a vertical distance Lz1 between the trolley and the top plane of the equipment carrier and a side shift distance Lx1 of the grabbing device of the trolley; and the first positioning sheet is a reflective sheet.

[0012] The trolley taking and placing goods positioning device as described above, optionally, the second sensor can emit a second light ray towards the equipment carrier, and the second light ray forms a light spot on the equipment carrier; and the second positioning sheet and the third positioning sheet are reflective sheets.

[0013] Further, the first positioning sheet is arranged on the center line of the equipment carrier which is parallel to the advancing direction of the trolley and is located between the goods placing position of the equipment carrier and the edge of the equipment carrier.

[0014] Further, the length of the second positioning sheet is less than the length of the light ray segment formed by the first light ray emitted by the first sensor on the equipment carrier, the width of the second positioning sheet is less than L*tanθ, L is the maximum value of the up-down moving range of the grabbing device of the trolley, θ is the included angle between the light ray emitted by the second sensor and the vertical plane which is parallel to the light ray segment formed by the first light ray emitted by the first sensor on the equipment carrier, and the area of the second positioning sheet is less than the area of the projection of the goods on the equipment carrier; the area of the third positioning sheet is not greater than the area of the top plane of the goods, and the center of the third positioning sheet coincides with the center of the top plane of the goods.

[0015] In order to achieve the above-mentioned second purpose, the present application adopts the following technical solutions:

[0016] The trolley system includes a trolley and the trolley taking and placing goods positioning device as described above.

[0017] The trolley includes a trolley frame body.

[0018] A walking device is arranged to drive the trolley frame body to move along the track arranged in the air.

[0019] A grabbing device is arranged to move up and down on the trolley frame body.

[0020] a side shifting device configured to control the grabbing device to shift in a horizontal direction;

[0021] a controller in communication connection with the walking device, the grabbing device and the side shifting device;

[0022] the first sensor and the second sensor are arranged on the overhead crane frame and in communication connection with the controller.

[0023] The overhead crane system as described above, optionally, the overhead crane further comprises a code scanner in communication connection with the controller.

[0024] In order to achieve the above-mentioned third object, the present application adopts the following technical solutions:

[0025] The overhead crane transportation method uses the overhead crane system as described above to transport goods, and the specific steps are as follows:

[0026] After the overhead crane approaches the target location, the controller controls the first sensor to work, and the first sensor emits light to the equipment platform;

[0027] If the light emitted by the first sensor irradiates the first positioning sheet, the first sensor obtains the vertical distance Lz1 between the overhead crane and the top plane of the equipment platform and the side shifting distance Lx1 of the grabbing device according to the reflected light, and sends a detection signal to the controller; if the light emitted by the first sensor does not irradiate the first positioning sheet, it is considered that the equipment platform position is abnormal, and the controller sends an alarm signal;

[0028] After the first sensor detects the first positioning sheet, the controller further obtains the descending distance Lz and the side shifting distance Lx of the grabbing device according to the vertical distance Lz1 between the overhead crane and the top plane of the equipment platform and the side shifting distance Lx1 of the grabbing device, and controls the second sensor to work, and the second sensor emits light to the equipment platform;

[0029] If the light emitted by the second sensor irradiates the second positioning sheet or the third positioning sheet, the controller controls the grabbing device to grab or put down the goods; if the light emitted by the second sensor does not irradiate the second positioning sheet or the third positioning sheet, it is considered that the equipment platform position is abnormal, and the controller sends an alarm signal;

[0030] After the second sensor detects the second positioning sheet or the third positioning sheet, the overhead crane completes the goods putting or taking action and goes to the next target location.

[0031] Further, the descending distance Lz of the grabbing device is Lz1+Z-h, wherein h is the distance between the bottom of the working plane of the bearing part on the goods and the equipment platform, Z is the compensation value of the first sensor relative to the grabbing device in the vertical direction; the side shift distance Lx of the grabbing device is Lx1+X, wherein X is the compensation value of the first sensor relative to the grabbing device in the horizontal direction.

[0032] Further, when the overhead traveling crane moves to the target position along the track, if the code scanner of the overhead traveling crane scans the two-dimensional code bound with the equipment platform, the control controls the overhead traveling crane to slow down, and controls the first sensor to start working, if the light emitted by the first sensor irradiates the first positioning sheet, the controller controls the overhead traveling crane to stop.

[0033] The above technical scheme can know that the overhead traveling crane taking and placing goods positioning device of the present application can detect whether the equipment platform is displaced, and dynamically adjust the taking and placing position parameters of the overhead traveling crane on the equipment platform through ranging, intelligently monitor the position of the equipment platform, ensure the safety and stability of the overhead traveling crane, solve the technical problem that the overhead traveling crane can still normally and safely take and place goods when the equipment platform is displaced, and detect whether there is an obstacle between the equipment platform and the overhead traveling crane, between the overhead traveling crane and the goods, improve the safety production capacity, and reduce the safety risk. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present application, the drawings needed in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0035] Figure 1 It is a schematic diagram of the present application embodiment when the overhead traveling crane places goods on the equipment platform;

[0036] Figure 2 It is a schematic diagram of the present application embodiment when the overhead traveling crane takes goods on the equipment platform;

[0037] Figure 3 It is a schematic diagram of the present application embodiment when the first sensor detects;

[0038] Figure 4 It is a flow chart of the overhead traveling crane transportation method of the present application embodiment;

[0039] Figure 5 It is a step flow chart of the overhead traveling crane taking and placing goods of the present application embodiment.

[0040] BRIEF DESCRIPTION OF DRAWINGS

[0041] 1 - first inductor 2 - second inductor 3 - first positioning sheet

[0042] 4 - second positioning sheet 5 - third positioning sheet 100 - crown block

[0043] 101 - crown block body 102 - grabbing device 103 - side shifting device

[0044] 104 - traveling device 200 - wafer box 300 - equipment stage

[0045] The specific embodiments of the present application are described in further detail below in conjunction with the accompanying drawings. DETAILED DESCRIPTION

[0046] The present application will be described in detail below in conjunction with the accompanying drawings. In the detailed description of the embodiments of the present application, the drawings of the device structure may be partially enlarged without the general proportion for the convenience of description, and the schematic diagram is only an example, which should not limit the scope of protection of the present application. It should be noted that the drawings are simplified and all use non-precise proportions, only to facilitate, clearly assist the purpose of describing the embodiments of the present application. At the same time, in the description of the present application, the terms "first", "second" and the like are only used for distinction, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features; the directions or positional relationships indicated by the terms "positive", "negative", "bottom", "upper", "lower", "front", "back", "left", "right" are based on the directions or positional relationships shown in the drawings, only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as limiting the present application. The device or element must have a specific orientation, be constructed and operated in a specific orientation.

[0047] In the description of the present application, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected", "connected" should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements, it can be wireless connection, or it can be wired connection. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0048] The current overhead crane system has fixed pick-up and drop-off position parameters. Once the parameters are set, the overhead crane will run along the track, confirm the arrival of the target equipment platform corresponding position through scanning and target equipment platform binding two-dimensional code, and then execute the pick-up and drop-off action according to the fixed pick-up and drop-off position parameters. Therefore, if the position of the target equipment platform changes, the overhead crane will not perform the action according to the new position of the target equipment platform, and may not be able to safely and accurately perform the pick-up and drop-off action. Some existing overhead crane monitoring systems can determine whether the target equipment platform has obstacles through image recognition, or detect whether the overhead crane has moved to the position and whether there are obstacles between the overhead crane and the platform through photoelectric sensors, so as to avoid the inability to accurately place or pick up goods. However, these monitoring systems cannot cope with the situation where the position of the equipment platform changes, and there is a risk of not being able to accurately and safely pick up and drop off goods.

[0049] However, during the use of the overhead crane and the equipment platform, there will always be uncontrollable variables such as mechanical wear and tear and human actions, especially in scenarios where external SMIF (Standard Mechanical Interface) is used as a wafer box platform for wafer processing equipment. The external SMIF is a device that can open the wafer box and place the wafer into the equipment. Since there is no hard connection between the external SMIF and the processing equipment, the SMIF will be removed during maintenance of the SMIF or the processing equipment, resulting in a change in the position of the SMIF. If the overhead crane can only pick up and drop off goods according to the original fixed pick-up and drop-off position parameters after the position of the SMIF changes, there will be a high risk of safety hazards.

[0050] To solve the above problems, the present application provides an overhead crane pick-up and drop-off positioning device that can detect whether the pick-up or drop-off position has changed and dynamically update the pick-up and drop-off position parameters. Through the overhead crane pick-up and drop-off positioning device, the overhead crane can detect whether the position of the equipment platform has changed and reposition the pick-up and drop-off position to calculate new pick-up and drop-off position parameters, so that the overhead crane can pick up and drop off goods according to the new pick-up and drop-off position parameters, thereby avoiding the situation where the equipment platform position changes and the overhead crane cannot safely and correctly pick up and drop off goods.

[0051] Embodiment 1

[0052] The present embodiment provides an overhead crane pick-up and drop-off positioning device. As shown in Figure 1 , Figure 2 and Figure 3 , the overhead crane pick-up and drop-off positioning device of the present embodiment includes a first sensor 1, a second sensor 2, a first positioning sheet 3, a second positioning sheet 4, and a third positioning sheet 5. The first sensor 1 and the first positioning sheet 3 form a first detection assembly, and the second sensor 2 and the second positioning sheet 4 and the third positioning sheet 5 form a second detection assembly.

[0053] The overhead crane 100 moves above the equipment carrier 300 along the track. The overhead crane 100 comprises a crane frame 101, a grabbing device 102, a side shifting device 103, a walking device 104 and a controller (not shown). The walking device 104 drives the crane frame 101 to move along the track which is suspended. The grabbing device 102 is carried by the side shifting device 103 and can be shifted horizontally, the shifting direction being perpendicular to the advancing direction of the overhead crane. The grabbing device 102 can be moved up and down relative to the crane frame 101, for example, the grabbing device 102 is driven to move vertically up and down by a motor and a belt. The side shifting device 103 can also be driven to move horizontally by a motor and a belt. The controller is in communication connection with the grabbing device 102, the side shifting device 103 and the walking device 104, and can send control instructions to the grabbing device 102, the side shifting device 103 and the walking device 104, so that the grabbing device 102, the side shifting device 103 and the walking device 104 perform corresponding actions according to the instructions to realize the taking and placing of goods.

[0054] When the overhead crane 100 moves to the position, the side shifting device 103 adjusts the position of the grabbing device 102 along the side shifting direction according to the taking and placing position parameters, and then the grabbing device 102 is lowered to place the goods on the equipment carrier 300 or to grab the goods from the equipment carrier 300.

[0055] The first sensor 1 and the second sensor 2 are both arranged on the crane frame 101. In the embodiment, the first sensor 1 and the second sensor 2 are arranged on the bottom of the crane frame 101. For the convenience of description, the front and back of the crane frame 101 are defined with respect to the advancing direction (indicated by the arrow A) of the overhead crane. Figure 1 The first sensor 1 is arranged on the front of the crane frame 101, and the first sensor 1 is used to detect the position of the equipment carrier 300 so that the overhead crane 100 can accurately stop to take and place goods.

[0056] The detection function of the first detection assembly is realized by the first sensor 1 in combination with the first positioning sheet 3. The first sensor 1 can emit light to the equipment carrier 300, and when the first sensor 1 receives the light reflected from the first positioning sheet 3, it is considered that the equipment carrier 300 is positioned, and the overhead crane 100 has moved above the equipment carrier 300. The first sensor 1 also has the function of measuring distance, and can calculate the vertical distance between the first sensor 1 and the plane (the equipment carrier) where the first positioning sheet 3 is arranged according to the time difference between the emission of light and the reception of light.

[0057] The first sensor 1 of the embodiment is a laser sensor, and the first positioning sheet 3 is a reflective sheet. The first sensor 1 emits light towards the equipment carrier 300, and a triangular light curtain is formed, and a light segment is projected on the equipment carrier 300. That is, the first sensor 1 emits a first light, and the light emitted by the first sensor 1 forms a light segment a on the equipment carrier 300, and the light segment a is perpendicular to the advancing direction of the crane 100. The length of the light segment a is less than the maximum side shift value of the grabbing device 102 (that is, within the side shift range of the grabbing device 102).

[0058] The first positioning sheet 3 is arranged on the equipment carrier 300, and the first positioning sheet 3 is located on the center line of the equipment carrier 300 which is parallel to the advancing direction of the crane. The first positioning sheet 3 is located between the wafer box placement position and the edge of the equipment carrier 300. In order to avoid the wafer box blocking the light emitted by the first sensor 1 and affecting the positioning, the first positioning sheet 3 should be as far away from the wafer box placement position as possible. In order to improve the measurement accuracy, the area of the first positioning sheet 3 should be as small as possible. The first positioning sheet 3 of the embodiment is a circular reflective sheet with a diameter of 1 mm.

[0059] During the advancing of the crane 100, if the first light emitted by the first sensor 1 hits the first positioning sheet 3, the first positioning sheet 3 will reflect the light, and the first sensor 1 can receive the reflected light. When the first light emitted by the first sensor 1 cannot irradiate the first positioning sheet 3, it can be confirmed that the equipment carrier 300 has moved a large distance and the position has changed.

[0060] Based on the time difference between the emission of the light and the reception of the light, the vertical distance between the plane where the first sensor 1 and the first positioning sheet 3 are located (the top plane of the equipment carrier) can be calculated. In the present application, the vertical distance is defined as the vertical distance Lz1 between the crane 100 and the top plane of the equipment carrier 300, and the distance between the center of the first positioning sheet 3 and the symmetrical center plane (plumb plane) of the crane frame body parallel to the advancing direction of the crane can be calculated. The distance is defined as the side shift distance Lx1 of the grabbing device 102. How to calculate the distance based on the time difference between the emission of the light and the reception of the light is a conventional technology, and many mature laser distance sensor products on the market can realize the corresponding distance measurement function. This part is not the innovation point of the present application, so the distance measurement principle of the first sensor will not be described here.

[0061] The second sensor 2 of the embodiment is also arranged at the bottom of the crane frame body 1. The second sensor 2 can be arranged at the front of the crane frame body 101 or at the rear of the crane frame body 102. The second sensor 2 of the embodiment is arranged at the rear of the crane frame body 101, that is, the first sensor 1 and the second sensor 2 are arranged in front of and behind the crane frame body 101.

[0062] The second sensor 2 is used to detect whether there is an obstacle between the overhead crane 100 and the equipment carrier 300 or between the overhead crane 100 and the wafer box 200, so as to realize that the overhead crane can safely take and place the goods. The second sensor 2 can emit light to the equipment carrier 300. The detection function of the second detection assembly is realized by the second sensor 2 in combination with the second positioning sheet 4 and the third positioning sheet 5.

[0063] The second sensor 2 in the embodiment is also a laser sensor. The second sensor 2 emits second light to the equipment carrier 300, and the light on the equipment carrier 300 is a light spot. The second positioning sheet 4 and the third positioning sheet 5 are also reflective sheets. The second positioning sheet 4 is arranged on the equipment carrier 300 and located at the wafer box placing position of the equipment carrier 300. The third positioning sheet 5 is arranged on the top plane of the wafer box 200, and in the embodiment, the third positioning sheet 5 is arranged on the “mushroom head” of the wafer box 200. The “mushroom head” (an elongated neck is formed on the wafer box 200 in the embodiment) is arranged on the wafer box 200 to facilitate the grabbing device of the overhead crane to grab the wafer box 200. Other forms of grabbing structures can also be used. When the second light emitted by the second sensor 2 hits the reflective sheet, the light is reflected and received by the second sensor 2. The light emitted by the second sensor 2 is obliquely incident on the equipment carrier 300. The oblique angle of the light is only required to ensure that after the first sensor 1 emits the light to the first positioning sheet 3 and the overhead crane stops, the second light emitted by the second sensor 2 can be incident on the second positioning sheet 4 or the third positioning sheet 5. The oblique angle of the light is related to the positions of the first sensor 1, the second sensor 2, the second positioning sheet 4 and the third positioning sheet 5, and can be adjusted according to the actual structure. As long as the light emitted by the second sensor 2 can be incident on the second positioning sheet 4 or the third positioning sheet 5 and the reflected light can be received after the overhead crane stops, the oblique angle is not limited here.

[0064] The second positioning sheet 4 in the embodiment is a rectangular reflective sheet. The length direction of the second positioning sheet 4 is perpendicular to the forward direction of the overhead crane, and the width direction of the second positioning sheet 4 is parallel to the forward direction of the overhead crane. The length of the second positioning sheet 4 is less than the length of the light segment a. At the same time, the length of the second positioning sheet 4 is less than the side length of the wafer box in the length direction of the second positioning sheet. The width of the second positioning sheet 4 is less than Lxtanθ, where L is the maximum value of the up-down moving range of the grabbing device 102, and θ is the included angle between the light emitted by the second sensor 2 and the vertical plane parallel to the light segment a. At the same time, the width of the second positioning sheet 4 is less than the side length of the wafer box in the length direction of the second positioning sheet. The area of the second positioning sheet 4 is also less than the projection area of the wafer box 200 on the top plane of the equipment carrier 300. The maximum value L of the up-down moving range of the grabbing device 102 is the maximum value of the vertical direction moving distance of the grabbing device 102 of the overhead crane in the working area, that is, the vertical direction moving distance of the grabbing device 102 of the overhead crane in a certain specific height working area is limited.

[0065] The third positioning sheet 5 of the embodiment is also a long rectangular reflective sheet, and the area of the third positioning sheet 5 is not greater than the area of the top plane of the wafer box 200. The center of the third positioning sheet 5 coincides with the center of the top plane of the wafer box 200.

[0066] When the second sensor 2 emits light and can receive the light reflected back from the second positioning sheet 4 or the third positioning sheet 5, it indicates that there is no obstacle between the crane 100 and the equipment platform 300, or between the crane 100 and the wafer box 200; if no light is reflected back to the second sensor 2, it indicates that there is an obstacle between the crane 100 and the equipment platform 300, or between the crane 100 and the wafer box 200, which cannot safely take and place the goods; or it indicates that the equipment platform 300 or the wafer box 200 has a large displacement and is not in a safe taking and placing position, and the second sensor 2 has not positioned the wafer box placing position or the wafer box 200.

[0067] The crane taking and placing goods positioning device of the embodiment can position the equipment platform 300 through the first sensor 1, and can measure the vertical distance Lz1 from the crane to the top plane of the equipment platform and the lateral displacement distance Lx1 of the grabbing device 102, and then re-determine the taking and placing position parameters (the taking and placing position parameters include the actual required lowering distance Lz of the grabbing device 102 in the vertical direction and the lateral displacement distance Lx of the grabbing device 102 relative to the first sensor 1 in the horizontal direction) according to Lz1 and Lx1. The grabbing device 102 acts according to the re-determined taking and placing position parameters after distance measurement, and the situation that the equipment platform position changes and the goods cannot be safely taken and placed does not occur; and the crane taking and placing goods positioning device can also detect whether there is an obstacle between the equipment platform 300 and the crane 100, or between the wafer box 200 and the crane, through the second sensor 2, to ensure the safety of taking and placing the goods.

[0068] Embodiment 2

[0069] The embodiment 2 provides a crane system based on the embodiment 1, which adopts the crane taking and placing goods positioning device in the embodiment 1 to realize the detection and positioning of the equipment platform 300 by the crane when taking and placing goods, and to realize the detection of whether the wafer box placing position or the wafer box 200 is in a safe taking and placing state, so as to avoid the situation that the equipment platform 300 is displaced and the crane cannot accurately and safely take and place the goods.

[0070] As shown in Figures 1 to 3 The crane system of the embodiment includes the crane 100, the first sensor 1, the second sensor 2, the first positioning sheet 3, the second positioning sheet 4 and the third positioning sheet 5, that is, the crane system includes the crane and the crane taking and placing goods positioning device of the embodiment 1.

[0071] The overhead crane 100 comprises an overhead crane frame 101, a grabbing device 102, a side shifting device 103, a walking device 104 and a controller. The walking device 104 drives the overhead crane frame 101 to move along the track arranged in the air. The grabbing device 102 is movably arranged on the overhead crane frame 101 relative to the overhead crane frame 101. The side shifting device 103 is used to carry the grabbing device 102 to shift in the horizontal direction (the shifting direction is perpendicular to the advancing direction of the overhead crane). The controller is in communication connection with the grabbing device 102, the side shifting device 103 and the walking device 104, and can send control instructions to the grabbing device 102, the side shifting device 103 and the walking device 104, so that the grabbing device 102, the side shifting device 103 and the walking device 104 perform corresponding actions of taking and placing the goods according to the instructions. The controller is also in communication connection with the first sensor 1 and the second sensor 2, and can receive the detection signals and ranging data of the first sensor 1 and the second sensor 2, and control the overhead crane to perform corresponding actions according to the detection signals and ranging data of the first sensor 1 and the second sensor 2.

[0072] A code scanner (not shown) is arranged on the overhead crane 100, and is used to scan the two-dimensional code bound with each equipment platform on the track. The code scanner is in communication connection with the controller. When the code scanner scans the two-dimensional code bound with the target equipment platform, the controller controls the overhead crane to slow down, and the equipment platform, the placement position of the wafer box and the positioning detection of the wafer box are performed by the first sensor 1 and the second sensor 2. After the positioning detection is completed, if there is no abnormality, the controller controls the side shifting device 103 to adjust the position of the grabbing device 102 in the side shifting direction according to the taking and placing position parameters, and then controls the grabbing device 102 to descend to place the goods on the equipment platform 300 or to grab the goods from the equipment platform 300.

[0073] The first sensor 1 of the embodiment is arranged at the front part of the overhead crane frame 101, and the second sensor 2 is arranged at the rear part of the overhead crane frame 101. The first sensor 1 and the second sensor 2 both emit light rays towards the equipment platform 300. The light ray emitted by the first sensor 1 forms a light curtain, and forms a light ray segment a on the equipment platform 300, which is perpendicular to the advancing direction of the overhead crane. The second sensor 2 emits a second light ray, which forms a light point on the equipment platform 300.

[0074] The first sensor 1 is used to detect the position of the equipment carrier 300 and measure the vertical distance between the trolley 100 and the top plane of the equipment carrier 300. The detection and measurement functions of the first detection assembly are realized by the first sensor 1 in combination with the first positioning sheet 3. The first sensor 1 emits light of a specific wavelength to the equipment carrier 300. If the light emitted by the first sensor 1 hits the first positioning sheet 3, the first positioning sheet 3 reflects the light, and the first sensor 1 can receive the light of the specific wavelength reflected back. When the first sensor 1 receives the light reflected back from the first positioning sheet 3, it is considered that the equipment carrier 300 is positioned, and the trolley 100 has moved above the equipment carrier 300. If the light emitted by the first sensor 1 cannot hit the first positioning sheet 3, it can be confirmed that the equipment carrier 300 has moved a large distance and the position has changed.

[0075] After the first sensor 1 receives the light reflected back by the first positioning sheet 3, the vertical distance Lz1 between the trolley 100 and the top plane of the equipment carrier 300, and the lateral displacement distance Lx1 of the grabbing device 102 can be calculated based on the time difference between the emitted light and the received light.

[0076] The second sensor 2 is used to detect whether there is an obstacle between the trolley 100 and the equipment carrier 300 or between the trolley 100 and the wafer box 200, so that the trolley can safely take and place the goods. The second sensor 2 can emit light to the equipment carrier 300. The detection function of the second detection assembly is realized by the second sensor 2 in combination with the second positioning sheet 4 and the third positioning sheet 5.

[0077] The second positioning sheet 4 is arranged on the equipment carrier 300 and located at the wafer box placement position of the equipment carrier 300. The third positioning sheet 5 is arranged on the top plane of the wafer box 200. When the light emitted by the second sensor 2 hits the reflective sheet (4, 5), the light is reflected and received by the second sensor 2.

[0078] When the second sensor 2 emits light of a specific wavelength and can receive the light of the specific wavelength reflected back from the second positioning sheet 4 or the third positioning sheet 5, it indicates that there is no obstacle between the trolley 100 and the equipment carrier 300 or between the trolley 100 and the wafer box 200; if the light emitted by the second sensor 2 cannot hit the second positioning sheet 4 or the third positioning sheet 5, it indicates that there is an obstacle between the trolley 100 and the equipment carrier 300 or between the trolley 100 and the wafer box 200, which cannot safely take and place the goods; or it indicates that the equipment carrier 300 or the wafer box 200 has moved a large distance and is not in the safe taking and placing position, the second sensor 2 has not positioned the wafer box placement position or the wafer box. At this time, the controller can issue an alarm signal to remind the staff to check.

[0079] When the overhead crane system of the embodiment transports goods, the overhead crane 100 moves along the track to the target location (where the target equipment carrier is located). When the overhead crane 100 scans the track two-dimensional code where the target location is located, the overhead crane slows down. The controller controls the first sensor 1 to start working, and the first sensor 1 emits light to the equipment carrier 300. If the light irradiates the first positioning sheet 3, the light is reflected by the first positioning sheet 3 and received by the first sensor 1. The controller controls the overhead crane 100 to stop by braking, indicating that the overhead crane reaches the goods depositing / picking location where the equipment carrier is located. Since the overhead crane stops according to the actual position of the equipment carrier, even if the equipment carrier is displaced in the direction of the advancement of the overhead crane, the position of the overhead crane is still the optimal goods depositing / picking location. When the positioning is detected, the first sensor 1 measures the vertical distance Lz1 from the overhead crane 100 to the equipment carrier 300 and the lateral displacement distance Lx1 of the grabbing device 102.

[0080] After the first sensor 1 irradiates the first positioning sheet 3, the controller controls the second sensor 2 to start working and emit light to the equipment carrier 300. If the light irradiates the second positioning sheet 4 or the third positioning sheet 5, it indicates that the equipment carrier 300 is in a safe goods depositing / picking location.

[0081] The controller controls the grabbing device 102 to act according to the depositing / picking position parameters. The descending distance of the grabbing device 102 in the vertical direction is Lz, and the lateral displacement distance of the grabbing device 102 in the horizontal direction is Lx. The controller further determines the actual descending distance Lz required by the grabbing device 102 and the lateral displacement distance Lx of the grabbing device 102 relative to the first sensor according to the vertical distance Lz1 from the overhead crane 100 to the top plane of the equipment carrier 300 and the lateral displacement distance Lx1 of the grabbing device 102. The aforementioned descending distance Lz of the grabbing device 102 and the lateral displacement distance Lx of the grabbing device 102 constitute the depositing / picking position parameters.

[0082] The lowering distance Lz of the grabbing device 102 is Lz1+Z-h; wherein h is the distance between the bottom of the working plane of the bearing part of the wafer box and the equipment platform, Z is the compensation value of the first sensor 1 relative to the grabbing device 102 in the vertical direction, and the absolute value is actually the distance between the working plane of the grabbing device 102 and the working plane of the bearing part of the wafer box when the first sensor 1 contacts the wafer box; when the first sensor 1 and the aforementioned working plane of the grabbing device are located at the same horizontal plane, the compensation value is zero; when the first sensor 1 is located higher than the aforementioned working plane of the grabbing device, the compensation value is negative, and vice versa. The side shift distance Lx of the grabbing device 102 relative to the first sensor 1 in the horizontal direction is Lx1+X; wherein X is the compensation value of the first sensor 1 relative to the grabbing device 102 in the horizontal direction, and the absolute value is actually the horizontal and vertical distance of the first sensor 1 relative to the vertical plane of the center of the side shift device (generally, the vertical plane of the center of the side shift device coincides with the center plane of the trolley frame); when the first sensor 1 is arranged at the center of the trolley frame in the horizontal direction, the compensation value is zero; when the first sensor 1 and the grabbing device are on the same side of the center plane of the trolley frame, the compensation value is negative, and vice versa. Since the first sensor 1 is installed on the trolley frame, its initial position relative to the grabbing device 102 is fixed, and the compensation values X and Z can be determined according to the installation position of the first sensor 1 and the initial position of the grabbing device 102. After the first sensor 1 and the grabbing device 102 are installed on the trolley frame 101, the wafer box can be other goods.

[0083] The trolley system of the embodiment is provided with a trolley taking and placing goods positioning device, which can position the equipment platform 300 through the first sensor 1 of the trolley taking and placing goods positioning device, and can measure Lz1 and Lx1, and then determine the taking and placing position parameters Lz and Lx according to Lz1 and Lx1. The grabbing device 102 acts according to the dynamically adjusted taking and placing position parameters Lz and Lx, and the situation that the equipment platform position changes and the goods cannot be safely taken and placed does not occur. Moreover, the trolley taking and placing goods positioning device can also detect whether there is an obstacle between the equipment platform 300 and the trolley 100, and between the wafer box 200 and the trolley, to ensure the safety of taking and placing goods.

[0084] Embodiment 3

[0085] Embodiment 3 is based on embodiment 2, and provides a trolley transportation method. The transportation method adopts the trolley system of embodiment 2 to transport the wafer box, and can realize the detection and positioning of the equipment platform 300 by the trolley when taking and placing goods, and the detection of the wafer box placing position or whether the wafer box 200 is in a safe taking and placing state, to avoid the situation that the equipment platform 300 is displaced and the trolley cannot accurately and safely take and place goods.

[0086] As Figure 1 , Figure 2 and Figure 3 shown, the overhead crane system includes an overhead crane and an overhead crane taking and placing goods positioning device, the overhead crane taking and placing goods positioning device includes a first sensor 1, a second sensor 2, a first positioning sheet 3, a second positioning sheet 4 and a third positioning sheet 5.

[0087] The overhead crane 100 includes an overhead crane frame body 101, a grabbing device 102, a side shifting device 103, a walking device 104 and a controller. The walking device 104 drives the overhead crane frame body 101 to move along the track arranged in the air. The grabbing device 102 is movably arranged on the overhead crane frame body 101 relative to the overhead crane frame body 101. The side shifting device 103 is used to carry the grabbing device 102 to shift in the horizontal direction. The controller is in communication connection with the grabbing device 102, the side shifting device 103 and the walking device 104, and can send control instructions to the grabbing device 102, the side shifting device 103 and the walking device 104, so that the grabbing device 102, the side shifting device 103 and the walking device 104 perform corresponding actions of taking and placing goods according to the instructions. The controller is also in communication connection with the first sensor 1 and the second sensor 2, can receive detection signals and ranging data of the first sensor 1 and the second sensor 2, and control the overhead crane to perform corresponding actions according to the detection signals and ranging data of the first sensor 1 and the second sensor 2.

[0088] The overhead crane 100 is provided with a code scanner in communication connection with the controller. When the code scanner scans the two-dimensional code bound with the target equipment platform, the controller controls the overhead crane to slow down, and the first sensor 1 and the second sensor 2 are used to detect the positions of the equipment platform and the wafer box, and the position of the wafer box. After the positioning detection is completed, if there is no abnormality, the controller controls the side shifting device 103 to adjust the position of the grabbing device 102 according to the taking and placing position parameters, and then controls the grabbing device 102 to descend and place the goods on the equipment platform 300 or grab the goods from the equipment platform 300.

[0089] Both the first sensor 1 and the second sensor 2 emit light towards the equipment platform 300. The light emitted by the first sensor 1 forms a light curtain, creating a light segment a on the equipment platform 300. Light segment a is perpendicular to the crane's forward direction. The first sensor 1 is used to detect the position of the equipment platform 300 and to measure the vertical distance between the crane 100 and the top plane of the equipment platform 300. The first sensor 1 emits light of a specific wavelength towards the equipment platform 300. If the light emitted by the first sensor 1 hits the first positioning plate 3, the first positioning plate 3 will reflect the light, and the first sensor 1 can receive the reflected light of the specific wavelength. When the first sensor 1 receives the light reflected from the first positioning plate 3, it is considered that the equipment platform 300 has been positioned, and the crane 100 has moved above the equipment platform 300, thus achieving positioning of the equipment platform 300. If the light emitted by the first sensor 1 cannot reach the first positioning plate 3, it can be confirmed that the equipment platform 300 has moved significantly and its position has changed.

[0090] The second sensor 2 emits a second light beam, forming a light spot on the equipment platform 300. The second sensor 2 is used to detect whether there are obstacles between the overhead crane 100 and the equipment platform 300, or between the overhead crane 100 and the wafer cassette 200, to ensure the safe loading and unloading of goods by the overhead crane. The second sensor 2 can emit light towards the equipment platform 300. The second positioning plate 4 is disposed on the equipment platform 300, located at the wafer cassette placement position. The third positioning plate 5 is disposed on the top surface of the wafer cassette 200. When the light emitted by the second sensor 2 hits the second positioning plate 4 on the equipment platform 300 or the third positioning plate 5 on the wafer cassette 200, the light is reflected and received by the second sensor 2.

[0091] When the light emitted by the second sensor 2 illuminates the second positioning plate 4 or the third positioning plate 5, it indicates that there are no obstacles between the overhead crane 100 and the equipment platform, or between the overhead crane 100 and the wafer cassette 200. If the light does not illuminate the second positioning plate 4 or the third positioning plate 5, i.e., no light is reflected back to the second sensor 2, it indicates that there are obstacles between the overhead crane 100 and the equipment platform 300, or between the overhead crane 100 and the wafer cassette 200, making it impossible to safely pick up or place goods; or it indicates that the equipment platform 300 or the wafer cassette 200 has undergone significant displacement and is not in a safe pick-up or place position, and the second sensor 2 has not located the wafer cassette placement position or has not located the wafer cassette at all. The wafer cassette can be other goods.

[0092] like Figure 4 As shown, the overhead crane transportation method in this embodiment includes the following steps:

[0093] The overhead crane proceeds to the target location;

[0094] When the crown approaches the target location, if the two-dimensional code of the target equipment carrier is scanned, the controller controls the first sensor 1 to work, and the first sensor 1 emits the first light to the equipment carrier 300;

[0095] If the light emitted by the first sensor 1 irradiates the first positioning sheet 3, the first sensor 1 obtains the vertical distance Lz1 from the crown 100 to the top plane of the equipment carrier 300 and the side shift distance Lx1 of the grabbing device 102 according to the reflected light, and sends a detection signal to the controller; if the light emitted by the first sensor 1 does not irradiate the first positioning sheet 3, it is considered that the equipment carrier position is abnormal, and the controller sends an alarm signal;

[0096] After the first sensor 1 detects the first positioning sheet 3, the controller can further obtain the lowering distance Lz and the side shift distance Lx of the grabbing device 102 according to the vertical distance Lz1 from the crown 100 to the top plane of the equipment carrier 300 and the side shift distance Lx1 of the grabbing device 102, and controls the second sensor 2 to work, and the second sensor 2 emits the second light to the equipment carrier 300;

[0097] If the light emitted by the second sensor 2 irradiates the second positioning sheet 4 or the third positioning sheet 5, it indicates that the position of the goods is normal or the position of the goods is normal; if the second positioning sheet 4 or the third positioning sheet 5 cannot be irradiated, it is considered that the equipment carrier position is abnormal, and the controller sends an alarm signal;

[0098] After the second sensor 2 detects the second positioning sheet 4 or the third positioning sheet 5, the controller controls the grabbing device 102 to grab the goods, or to put down the goods; after the crown completes the goods putting or taking action, it goes to the next target location.

[0099] The steps of the crown transportation method of the embodiment will be described below with the example that the crown system executes the goods taking action and then sends the taken goods to another location. The step flow is as shown in Figure 5 .

[0100] The crown advances along the track to grab the goods at the goods taking location; when the code scanner on the crown scans the track two-dimensional code where the goods taking location is located, it indicates that it approaches the goods taking location, that is, a signal is sent to the controller, the controller controls the crown to advance at a reduced speed, and at the same time sends a control instruction to the first sensor 1, so that the first sensor 1 starts to work;

[0101] The first sensor 1 emits light to the equipment platform 300, if the light irradiates the first positioning sheet 3 on the equipment platform 300, it indicates that the trolley reaches the pickup location, that is, a signal of detecting the equipment platform 300 is sent to the controller, the controller controls the walking device 104 to stop by brake, and controls the second sensor 2 to start working, at the same time, the first sensor 1 measures the vertical distance Lz1 from the trolley 100 to the equipment platform 300 and the side shift distance Lx1 of the grabbing device 102 and sends to the controller, after the controller receives the ranging data sent by the first sensor 1, the pickup and drop position parameters (Lx, Lz) are calculated; if the light emitted by the first sensor 1 does not irradiate the first positioning sheet 3 on the equipment platform 300, it indicates that the position of the equipment platform 300 is abnormal, the equipment platform 300 has a large displacement, which exceeds the detection range, and the controller sends an alarm signal;

[0102] The second sensor 2 emits light to the equipment platform, if the light irradiates the third positioning sheet 5 on the top of the goods, it indicates that the position of the goods is normal, the controller controls the side shift device 103 and the grabbing device 102 to act according to the pickup and drop position parameters, and the goods are grabbed; if the light emitted by the second sensor 2 cannot irradiate the third positioning sheet 5 on the top of the goods on the equipment platform 300, it indicates that there is an obstacle on the equipment platform 300 or the equipment platform 300 has a large displacement, the pickup location is not safe, and the controller alarms at this time;

[0103] After the trolley picks up the goods, the goods are sent to the drop-off location; when the code scanner on the trolley scans the track two-dimensional code at the drop-off location, a signal is sent to the controller, the controller controls the trolley to slow down and advance, and at the same time sends a control instruction to the first sensor 1, so that the first sensor 1 starts working;

[0104] The first sensor 1 emits light to the equipment platform 300, if the light irradiates the first positioning sheet 3 on the equipment platform 300, it indicates that the trolley reaches the pickup location, that is, a signal of detecting the equipment platform 300 is sent to the controller, the controller controls the walking device 104 to stop by brake, and controls the second sensor 2 to start working, at the same time, the first sensor 1 measures the vertical distance Lz1 from the trolley 100 to the equipment platform 300 and the side shift distance Lx1 of the grabbing device 102 and sends to the controller, after the controller receives the ranging data sent by the first sensor 1, the pickup and drop position parameters (Lx, Lz) are calculated; if the light emitted by the first sensor 1 does not irradiate the first positioning sheet 3 on the equipment platform 300, it indicates that the position of the equipment platform 300 is abnormal, the equipment platform 300 has a large displacement, which exceeds the detection range, and the controller sends an alarm signal;

[0105] The second sensor 2 emits light to the equipment carrier 300, if the light irradiates the second positioning sheet 4 at the goods placing position of the equipment carrier 300, it indicates that the goods placing position is normal, the controller controls the side shift device 103 and the grabbing device 102 to act according to the taking and placing position parameters, and places the goods on the equipment carrier 300; if the second sensor 2 cannot detect the second positioning sheet 4 on the equipment carrier 300, it indicates that there is an obstacle on the equipment carrier 300 or the equipment carrier has a large displacement, and the goods placing position is not safe, at this time, the controller alarms.

[0106] The first sensor and the second sensor are arranged on the crown block frame body, and the positioning sheet matched with the first sensor is arranged on the equipment carrier and the top of the goods, the displacement of the equipment carrier can be detected through the first sensor, the action is not executed mechanically according to the fixed taking and placing position parameters, the goods cannot be accurately and safely grabbed or placed, the distance measuring data of the first sensor is used for dynamically adjusting the taking and placing position parameters of the crown block, the position of the equipment carrier is intelligently monitored, when the equipment carrier has a limited displacement, the goods can still be normally and safely taken and placed, the safety and stability of the crown block taking and placing are ensured. The abnormal situation of whether there is an obstacle between the crown block and the equipment carrier and between the crown block and the goods can be detected through the second sensor, the early warning is strengthened, the safety risk is reduced, the technical blank is filled, the safety and stability of the crown block operation are ensured, the loss can be reduced, and great economic value is achieved.

[0107] The above description of disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A positioning device for a crane to pick up or place a load on a device table; characterized in that, The application relates to a positioning device for a crane taking and placing goods, which comprises the following components: a first detection component and a second detection component; the first detection component comprises a first sensor arranged on the crane and a first positioning sheet arranged on the equipment platform, and is used for detecting whether the equipment platform is displaced and measuring the distance; the second detection component comprises a second sensor arranged on the crane, a second positioning sheet arranged on the equipment platform and a third positioning sheet arranged on the top of the goods, and is used for detecting whether there is an obstacle between the crane and the equipment platform and between the crane and the goods; a controller in communication connection with the first sensor and the second sensor, the first sensor emits light to the equipment platform, the light is reflected by the first positioning sheet and received by the first sensor when the light irradiates the first positioning sheet, and the controller controls the crane to stop by braking.

2. The trolley put-and-take positioning device of claim 1, wherein: The first sensor is arranged at the front of the crane, the first sensor can emit first light towards the equipment platform, the first light forms a light line segment on the equipment platform, which is perpendicular to the advancing direction of the crane; the distance measured by the first detection component comprises a vertical distance Lz1 between the crane and the top plane of the equipment platform and a side displacement distance Lx1 of the grabbing device of the crane; the first positioning sheet is a reflective sheet.

3. The trolley put-and-take positioning device of claim 1, wherein: The second sensor can emit second light towards the equipment platform, the second light forms a light spot on the equipment platform; the second positioning sheet and the third positioning sheet are reflective sheets.

4. The trolley put and take positioning device of claim 2, wherein: The first positioning sheet is arranged on the center line of the equipment platform, which is parallel to the advancing direction of the crane, and is located between the goods placing position of the equipment platform and the edge of the equipment platform.

5. The trolley put-and-take positioning device of claim 3, wherein: The length of the second positioning sheet is smaller than the length of the light line segment formed by the first light emitted by the first sensor on the equipment platform, the width is smaller than L*tan theta, L is the maximum value of the up-down moving range of the grabbing device of the crane, theta is the included angle between the second light emitted by the second sensor and the vertical plane parallel to the light line segment formed by the first light emitted by the first sensor on the equipment platform, and the area of the second positioning sheet is smaller than the projection area of the goods on the equipment platform; the area of the third positioning sheet is not larger than the area of the top plane of the goods, and the center of the third positioning sheet coincides with the center of the top plane of the goods.

6. A crown block system characterized by, The application further relates to a crane and the crane taking and placing goods positioning device according to any one of claims 1 to 5. The crane comprises a crane frame body. A walking device is arranged to drive the crane frame body to move along the track arranged in the air. A grabbing device is arranged to move up and down on the crane frame body. A side displacement device is arranged to control the grabbing device to side-displace in the horizontal direction. A controller is in communication connection with the walking device, the grabbing device and the side displacement device. The first sensor and the second sensor are arranged on the crane frame body and are in communication connection with the controller. The crane further comprises a code scanner, which is in communication connection with the controller.

7. The overhead trolley system of claim 6, wherein: ​ 8. A method of transporting a crown block, characterized by: The overhead traveling crane system according to any one of claims 6-7 is used for transporting goods, and the specific steps are as follows: After the overhead traveling crane approaches the target position, the controller controls the first sensor to work, and the first sensor emits light to the equipment platform; If the light emitted by the first sensor irradiates the first positioning sheet, the first sensor obtains the vertical distance Lz1 between the overhead traveling crane and the top plane of the equipment platform and the lateral displacement distance Lx1 of the grabbing device according to the reflected light, and sends a detection signal to the controller; if the light emitted by the first sensor does not irradiate the first positioning sheet, it is considered that the equipment platform position is abnormal, and the controller sends an alarm signal; After the first sensor detects the first positioning sheet, the controller further obtains the descending distance Lz and the lateral displacement distance Lx of the grabbing device according to the vertical distance Lz1 between the overhead traveling crane and the equipment platform and the lateral displacement distance Lx1 of the grabbing device, and controls the second sensor to work, and the second sensor emits light to the equipment platform; If the light emitted by the second sensor irradiates the second positioning sheet or the third positioning sheet, the controller controls the grabbing device to grab or drop the goods; if the light emitted by the second sensor does not irradiate the second positioning sheet or the third positioning sheet, it is considered that the equipment platform position is abnormal, and the controller sends an alarm signal; After the second sensor detects the second positioning sheet or the third positioning sheet, the overhead traveling crane completes the goods dropping or taking action and goes to the next target position.

9. The overhead trolley transport method of claim 8, wherein: The descending distance Lz of the grabbing device is Lz1+Z-h; wherein h is the distance from the bottom end of the working plane of the load-bearing component provided on the goods to facilitate the grabbing of the device to the equipment platform, and Z is the compensation value of the first sensor relative to the grabbing device in the vertical direction; the lateral displacement distance Lx of the grabbing device is Lx1+X, wherein X is the compensation value of the first sensor relative to the grabbing device in the horizontal direction.

10. The overhead trolley transport method of claim 8, wherein: When the overhead traveling crane goes to the target position along the track, if the code scanner of the overhead traveling crane scans the two-dimensional code bound with the equipment platform, the controller controls the overhead traveling crane to slow down, and controls the first sensor to start working, and if the light emitted by the first sensor irradiates the first positioning sheet, the controller controls the overhead traveling crane to stop.

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