KR20070080874A - Automatic guided vehicle - Google Patents

Abstract

An automatic guided vehicle is provided to miniaturize the automatic guided vehicle by replacing minute drive units by a main drive unit, thereby reducing the manufacturing cost. An automatic guided vehicle includes a body(110), a driving unit(130), a steering unit(140), sensing modules, and a control unit(160). An object is loaded on the body. The driving unit linearly moves the body. The steering unit rotates the body. The sensing modules confirm a position confirmation mark and detect the separated distance between the position confirmation mark and the body by emitting a signal toward the position confirmation mark installed at a goal point. The control unit moves the body to the goal point by controlling the driving unit and the steering unit and performs minute position compensation and posture compensation of the body with respect to the goal point according the separated distance.

Description

Unmanned Carrier {AUTOMATIC GUIDED VEHICLE}

1 is a perspective view showing a loading portion of a conventional unmanned conveying device.

Figure 2 is a plan view showing an unmanned conveying device according to an embodiment of the present invention.

3 is a front view of the unmanned conveying device shown in FIG. 2.

4 is a plan view of the sensing modules and the positioning mark shown in FIG.

FIG. 5 is a block diagram for explaining a position control method of the unmanned transport apparatus illustrated in FIG. 2.

FIG. 6 is a speed graph of the unmanned conveying device shown in FIG. 2.

7 and 8 are plan views of the sensing modules shown in FIG. 2.

<Description of the symbols for the main parts of the drawings>

100: Unmanned transportation apparatus 105: Equipment which is targeted for work

110: body 115: frame part

117: Wheel 118: Secondary wheel

120: Loading part 122: Rack

124 ： lifter 126 ： slider

151,155: sensing module 160: control unit

170: Position confirmation mark

The present invention relates to an unmanned conveying device. More particularly, the present invention relates to an apparatus for automatically transporting an object in a factory or a warehouse.

In general, many manufacturing and logistics processes require frequent transport of objects. For example, a semiconductor device may include a semiconductor chip manufacturing process of manufacturing a semiconductor chip in which an integrated circuit is formed on a silicon substrate, and electrically inspecting and sorting the semiconductor chip. It is manufactured through an electrically die sorting (EDS) process, a packaging process for protecting a semiconductor chip, and a package mounted on a circuit board. In order to perform such unit processes, the semiconductor substrates are stored in a predetermined container and transported to a semiconductor substrate processing facility where the process is performed.

At present, the use of unmanned transportation devices is increasing rapidly to achieve the purpose of reducing the manufacturing cost, speedy manufacturing process, safety accident prevention. In the unmanned transportation device, the improvement of the positioning ability is important above all. That is, the unmanned vehicle must be able to carry the object at the correct point.

At present, the positioning capability of the general unmanned conveying device is not so excellent. Therefore, in the field of producing and handling expensive products such as semiconductor devices, a lot of research and costs have been invested to improve the positioning capability of the unmanned transportation device.

The unmanned transport apparatus includes a vehicle body on which an object is largely loaded, a traveling unit for driving the vehicle body, a fine drive unit for adjusting the position and attitude of the vehicle body, a sensing unit, and a control unit. The vehicle body comprises a loading unit for loading and unloading an object into a work target facility, and a frame unit including the loading unit and a traveling unit and a control unit. The loading unit is moved to the work target facility along the frame unit, and then finely adjusts the position and posture on the load unit, and then loads and unloads the object into the work target facility. Hereinafter, with reference to the drawings will be described in detail with respect to the loading portion of the conventional unmanned conveying device.

1 is a schematic perspective view for explaining a loading portion of a conventional unmanned conveying device.

Referring to FIG. 1, the loading unit 10 includes a rack 20 on which an object is loaded, a slider 30 for sliding the rack 20 in a horizontal direction, and a lifting and lowering of the rack 20 in a vertical direction. Lifter 35, fine drive unit 40 for finely adjusting the position and posture of rack 20, and sensor unit 50 for detecting the relative position of rack 20 relative to the work facility (not shown). ).

The fine drive unit 40 includes a horizontal rotating motor 41, a horizontal rotating reducer 42, and a linear moving motor 45. The sensor unit 50 comprises laser sensors 51, 52 and a reader 55.

The relative position of the loading unit 10 with respect to the operation target facility is sensed by the sensor unit 50 in the loading unit 10 transferred adjacent to the operation target facility. Thereafter, the position and attitude correction of the loading unit 10 with respect to the work target facility is performed by the fine driving unit 40.

In more detail, the sensor unit 50 detects the degree in which the loading part 10 is inclined from the work target facility, and the degree in which the load unit 10 is disposed inclined. For this purpose, the reader 55 must first detect the barcode displayed on the facility to be worked on. The fine drive unit 40 moves the loading part 10 to the left and right until the reader 55 detects the barcode.

When the reader 55 detects the bar code, the laser sensors 51 and 52 measure the distance between the loading unit 10 and the target equipment. If the distances measured from the laser sensors 51 and 52 are different from each other, the loading part 10 is considered to be inclined from the work target equipment and the loading part 10 is rotated. Also in this case, the fine drive unit 40 is used.

The error range of the unmanned conveying device used in the semiconductor manufacturing process is about 10 millimeters (mm) in the traveling direction and about ± 1 degree in the horizontal plane. In order to control the unmanned conveying device satisfactorily in the above error range, much more complicated and accurate position and attitude correction control than the above is required. Therefore, a control device having excellent arithmetic performance is required, and a very precise fine drive unit 40 is required.

Given that good control devices and precise fine drives are generally expensive, it is obvious that it will be costly to improve the positioning capabilities of the unmanned conveying device. In fact, the unmanned transport device used in the semiconductor manufacturing process is several times more expensive than the unmanned transport device used in the logistics classification process.

In addition, in order to improve the positioning capability of the unmanned conveying device, it is necessary to further mount a fine driving device, so that the size of the unmanned conveying device becomes large and complicated. Therefore, a lot of space is required for the movement of the unmanned conveying device, and when an abnormality is found in the unmanned conveying device, it cannot be quickly acted on.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a simple unmanned transport apparatus capable of performing fine position and posture correction as a driving device for driving.

In order to achieve the above object of the present invention, the unmanned transport apparatus according to the preferred embodiment of the present invention includes a vehicle body on which an object is loaded, a driving unit for linearly moving the body, a steering unit for rotating the body, and a target point. The sensing module emits a signal toward the installed positioning mark and checks the positioning mark, and also controls the sensing modules and the driving unit and the steering unit to detect the degree of separation between the positioning mark and the vehicle body. And a control unit that performs fine position correction and attitude correction of the vehicle body with respect to the target point according to the degree.

The vehicle body is provided with a loading unit for lifting and unloading an object at a target point by lifting and sliding in the vertical direction, and wheels to support the loading unit from the ground and to have driving and steering units installed adjacent to the wheels. It may include a frame portion. Two sensing modules may be installed, and the sensing modules may be installed at intervals smaller than the width of the positioning mark.

According to the invention, fine drive units can be replaced with main drive units in an unmanned conveying device. Therefore, the size of the unmanned conveying device can be reduced, and the manufacturing cost can be reduced. In addition, by improving the control performance of the main drive unit, it is possible to ensure the operation reliability of the unmanned conveying device, and to perform a fast conveying process.

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to the unmanned transport device according to the preferred embodiments of the present invention, the present invention is not limited or limited by the following embodiments.

2 is a schematic plan view for explaining an unmanned conveying device according to an embodiment of the present invention, Figure 3 is a schematic front view of the unmanned conveying device shown in Figure 2, Figure 4 is shown in Figure 3 A plan view schematically showing one sensing module and a positioning mark.

2 to 4, the unmanned transportation device 100 is a logistics automation device that moves along a predetermined track in a factory and transports an object, and includes a vehicle body 110, a driving unit 130, and a steering ( steering unit 140, first and second sensing modules 151 and 155, and control unit 160.

First, the vehicle body 110 is composed of a frame portion 115 and the mounting portion 120 largely.

The frame part 115 forms the basis of the vehicle body 110 and determines the external shape of the vehicle body 110. Accordingly, the frame 115 has a width W and a length L that are substantially the same as the vehicle body 110.

The loading part 120 is installed at the center of the upper end of the frame part 115, and the wheels 117 are installed at both lower ends of the frame part 115. Although not shown in the drawings, the frame unit 115 may be further equipped with a power supply, a converter, a battery, an anti-collision sensor, an antenna, and the like.

The frame part 115 including the loading part 120 is spaced apart from the ground by the wheels 117. The wheels 117 may be composed of one or more sets of driving wheels and steering wheels, and may further include an auxiliary wheel 118.

The driving unit 130 and the steering unit 140 are connected to each wheel 117. The wheels 117 are rotated by the driving unit 130 and tilted by the steering unit 140. In this case, the steering unit 140 directly changes the rotation axis of the wheels 117 or adjusts the rotation ratio of the wheels 117 to rotate the frame part 115 including the loading part 120. The vehicle body 110 is moved in the X-axis direction (front and rear direction) by the driving unit 130, and is rotated on the XY axis plane by the steering unit 140.

The driving unit 130 and the steering unit 140 may be configured using a motor, a speed reducer, a power transmission device, and the like. As the motor, a DC motor, a brushless motor, or the like may be used. The driving unit 130 and the steering unit 140 according to the present exemplary embodiment are substantially the same as the accelerator and the steering apparatus for moving the unmanned transportation apparatus 100 to a target point in the related art, and thus a detailed description thereof will be omitted. If you can easily understand this.

As will be described again below, the unmanned conveying device 100 according to the present embodiment does not include a separate fine driving device for fine position adjustment on the XY axis plane. The unmanned transport device 100 basically performs fine adjustment of the unmanned transport device 100 by using the driving unit 130 and the steering unit 140 necessary to move the unmanned transport device 100.

The loading unit 120 is a device for loading and unloading an object to the work target facility 105 located at a target point. The rack 122 in which the object is loaded and the rack 122 in the Z-axis direction (vertical direction) And a slider 126 for sliding the rack 122 in the Y-axis direction (left and right directions) for elevating and lowering.

The rack 122 receives the movement force in the Z-axis and Y-axis directions from the lifter 124 and the slider 126 to unload the object to the work facility 105, or load the object from the work facility 105. .

The loading unit 120 according to the present exemplary embodiment does not have a separate fine driving device for finely moving in the X-axis direction and finely rotating along the XY-axis plane on the frame 115. The X-axis movement of the loading unit 120 and the rotation on the XY-axis plane are performed by the driving unit 130 and the steering unit 140.

The conventional unmanned conveying device moves adjacent to the work target facility 105 by using the accelerator and the steering device, and then performs fine position adjustment of the loading unit with respect to the work target facility 105 through a separate fine drive device. . In addition, in order to rotate the loading unit, a motor for rotational driving was additionally required. Therefore, the structure of the loading part is complicated, the manufacturing cost of the loading part is expensive, and the time for adjusting the position to the target point is required.

The unmanned transportation device 100 according to the present embodiment may effectively solve the above-mentioned problems by interlocking the first and second sensing modules 151 and 155 with the driving and steering units 130 and 140.

The first and second sensing modules 151 and 155 are installed at the lower end in the Y-axis direction of the loading part 120. The first and second sensing modules 151 and 155 emit signals in the Y-axis direction to check and adjust the relative position of the loading unit 120 with respect to the target point.

The first and second sensing modules 151 and 155 are installed on the loading part 120 to be spaced apart by the first distance L1. In this case, the first distance L1 means a distance in the X-axis direction. The first distance L1 is smaller than the width W1 of the positioning mark 170 provided in the work target facility 105. When the loading unit 120 is positioned at the target point, the first and second sensing modules 151 and 155 may be separated from each other by the fourth interval L4 from both ends of the positioning mark 170. In this case, the fourth interval L4 means a distance in the X-axis direction.

The first and second sensing modules 151 and 155 emit signals to the positioning marks 170, respectively, and the positioning marks 170 reflect the signals to the first and second sensing modules 151 and 155. The first and second sensing modules 151 and 155 detect the second and third distances L2 and L3 between the load unit 120 and the target point from the round trip time of the signals.

The first and second sensing modules 151 and 155 are distance sensing sensors. For example, the first and second sensing modules 151 and 155 may be laser beam sensors or ultrasonic sensors.

The positioning mark 170 is selected according to the type of the first and second sensing modules 151 and 155. The positioning mark 170 is made of a material capable of effectively reflecting signals emitted from the first and second sensing modules 151 and 155. For example, the positioning mark 170 may be made of a mirror or aluminum material.

The distance information detected from the first and second sensing modules 151 and 155 is provided to the control unit 160. In this case, the first and second sensing modules 151 and 155 and the control unit 160 may be connected in a wired, wireless or contactless manner.

The control unit 160 includes a microprocessor, a RAM, a digital input / output device, an analog input / output device, a serial port, a parallel port, an encoder port, and the like, and is built in the vehicle body 110. The control unit 160 controls the driving unit 130 and the steering unit 140 according to the distance information to adjust the position of the unmanned conveying apparatus 100 with respect to the target point, and the object to the unmanned conveying apparatus 100. Perform overall control function for the unmanned transport device 100 for loading and unloading. Hereinafter, the position control method of the unmanned transport apparatus 100 will be described in detail.

FIG. 5 is a block diagram for explaining a position control method of the unmanned conveying device shown in FIG. 2, and FIG. 6 is a speed graph of the unmanned conveying device shown in FIG. 2.

5 and 6, the control unit 160 accelerates and moves the unmanned transport device 100 to move the stationary unmanned transport device 100 to a target point (S110). The unmanned conveying device 100 is accelerated during the first time T1.

The movement trace of the unmanned conveying device 100 is programmed in the control unit 160. The control unit 160 controls the driving direction and the speed of the unmanned transportation device 100 by controlling the driving unit 130 and the steering unit 140 according to the programmed movement trajectory.

When the unmanned transport device 100 reaches the target speed V1, the control unit 160 moves the unmanned transport device 100 at a constant speed V1 at a constant speed. The target speed V1 may be determined according to the moving distance of the unmanned transportation device 100, the surrounding environment, whether the object is loaded or the like. The unmanned transportation device 100 is continuously moved for a second time T2 before the second sensing module 155 is operated.

The control unit 160 checks in real time the operating state of the first and second sensing modules 151 and 155 at the same time as the unmanned transport device 100 is moved (S120).

When the second sensing module 155 detects the positioning mark 170 and operates during the constant speed movement, the second sensing module 155 transmits a detection signal to the control unit 160. The control unit 160 checks both operating states of the first and second sensing modules 151 and 155 (S120).

When only the second sensing module 155 is operated (S130), the control unit 160 continues to move the unmanned transport device 100 in the same direction as the present (S135). In this case, the unmanned transportation device 100 is decelerated. The unmanned transportation device 100 is decelerated for a third time T3 before the first sensing module 151 is operated.

If only the first sensing module 151 is operated (S140), the control unit 160 moves the unmanned transport device 100 in the opposite direction to the present (S145). Even in this case, the unmanned conveying device 100 is decelerated until the second sensing module 155 is operated.

When the unmanned transportation device 100 moves in the normal direction, the first sensing module 151 should be operated after the second sensing module 155 is operated. However, if the first sensing module 151 is operated first, it may be considered that the unmanned transportation device 100 moves abnormally. If the second sensing module 155 does not operate even when the unmanned conveying device 100 is moved in the opposite direction for a predetermined time, the control unit 160 considers that an abnormality has occurred in the unmanned conveying device 100 and stops the conveying process. (S149).

When both of the first and second sensing modules 151 and 155 are operated, the control unit 160 moves the unmanned transportation device 100 at a constant speed V2 at a constant speed. In this case, the unmanned transportation device 100 is moved at a constant speed at the lowest speed V2 for the fourth time T4. The minimum speed V2 is similar to the drive speed of the fine drive device in order to adjust the fine position of the load in the conventional unmanned transport device. For example, the lowest speed V2 may be several tens of millimeters per millimeter (mm).

The control unit 160 moves the unmanned transport device 100 at the lowest speed V2 and performs fine position control of the unmanned transport device 100.

The control unit 160 moves the unmanned transport device 100 within a range in which the first and second sensing modules 151 and 155 do not deviate from the positioning mark 170. For example, the control unit 160 may move the unmanned transport device 100 according to Equation 1 below from a time point at which the detection signal is transmitted from the first sensing module 151.

[Equation 1]

In Equation 1, D represents a distance that the unmanned transport device 100 moves at the lowest speed V2, L1 represents a first distance from which the first and second sensing modules 151 and 155 are spaced apart, and L4 Denotes a distance from which the first and second sensing modules 151 and 155 are separated from both ends of the positioning mark 170.

When the unmanned conveying device 100 is moved according to Equation 1, the first and second sensing modules 151 and 155 do not deviate from the positioning mark 170.

The moving distance of the unmanned transport device 100 at the minimum speed V2 may be calculated using a pulse signal generated in proportion to the rotation speed of the wheels 117. The control unit 160 calculates the number of revolutions of the wheels 117 from the first time point at which the detection signal is transmitted from the first sensing module 151 to the distance at which the unmanned transportation device 100 should move at the minimum speed V2. The unmanned conveying device 100 is moved to fit. As a result, the unmanned conveying device 100 is positioned such that the first and second sensing modules 151 and 155 are separated from each other by the fourth interval L4 from both ends of the positioning mark 170.

As described above, the primary movement of the unmanned conveying device 100 is completed. Substantially no other driver is required besides the driving unit 130 and the steering unit 140 in the primary movement.

Subsequently, the control unit 160 secondly moves the unmanned transportation device 100 with respect to the positioning mark 170 to perform fine positioning. Hereinafter, the fine position and attitude control of the unmanned transport device 100 performed after the first and second sensor modules are operated will be described in detail.

7 and 8 are schematic plan views of the sensing modules shown in FIG. 2.

Referring to FIGS. 7 and 8, first, the control unit 160 checks the position with the first and second sensing modules 151 and 155 using distance information provided from the first and second sensing modules 151 and 155. The second and third distances L2 and L3 between the marks 170 are calculated, respectively.

When the unmanned transportation device 100 is positioned at the target point, the second distance L2 and the third distance L3 are substantially the same. When the second distance L2 and the third distance L3 are not substantially the same, or when the second and third distances L2 and L3 are larger than a preset value, the control unit 160 may unmanned conveying device 100 Rotate or move the) to compensate.

When both of the second and third distances L2 and L3 are smaller than the preset value, that is, when the first and second sensing modules 151 and 155 are located within a predetermined range from the positioning mark 170, the control unit ( 160 determines whether the unmanned vehicle 100 rotates using the difference values between the second and third distances L2 and L3 (S150). When the difference between the second and third distances L2 and L3 is greater than the preset error value, the control unit 160 rotates the unmanned conveying device 100 (S155).

The rotation direction of the unmanned conveying device 100 is determined by comparing the second and third distances L2 and L3. The control unit 160 rotates the unmanned transportation device 100 clockwise when the second distance L2 is greater than the third distance L3, and the second distance L2 is smaller than the third distance L3. In this case, the unmanned transportation device 100 is rotated counterclockwise (S155). In this case, the control unit 160 performs the second movement by using the driving unit 130 and the steering unit 140 which are used in the first movement in the same manner. The control unit 160 may rotate the unmanned transportation device 100 according to Equation 2 below.

[Equation 2]

In Equation 1, θ represents the rotation angle of the unmanned conveying device 100 on the XY axis plane, L1 represents the X axis direction interval of the first and second sensing modules 151, 155, L2 is the first The distance in the Y-axis direction between the sensing module 151 and the positioning mark 170, and L3 represents the distance in the Y-axis direction between the second sensing module 155 and the positioning mark 170.

Equation 2 is a tangent of a general triangle. The control unit 160 rotates the unmanned transport device 100 to correspond to the rotation angle θ of the unmanned transport device 100. In this case, the control unit 160 uses the driving unit 130 and the steering unit 140 which are used in the first movement in the same manner. In more detail, the control unit 160 adjusts the rotation ratio of the wheels 117 to rotate by the rotation angle θ of the unmanned transportation device 100 or smaller than the rotation angle θ. Alternatively, the control unit 160 may rotate the unmanned transportation device 100 by changing the rotation direction of the wheels 117 differently.

As described above, the secondary movement of the unmanned conveying device 100 is completed (S160). Through the secondary movement, the fine movement of the unmanned transportation device 100 with respect to the positioning mark 170 on the XY axis plane is completed. In more detail, the control unit 160 substantially matches the second distance L2 and the third distance L3 by the second movement, and the second and third distances L2 and L3 are preset values. Make it substantially the same or smaller. In addition, the unmanned transportation device 100 is positioned such that the first and second sensing modules 151 and 155 are separated from the both ends of the positioning mark 170 by a fourth interval L4, respectively.

Substantially no other driver is required besides the driving unit 130 and the steering unit 140 in the secondary movement. That is, the unmanned transportation device 100 according to the present embodiment performs both the primary and secondary movements by using the driving unit 130 and the steering unit 140.

Subsequently, the control unit 160 controls the lifter 124 and the slider 126 of the loading unit 120 to load the object into the rack 122 or to unload the object from the rack 122. Object loading and unloading method of the loading unit 120 is substantially the same as the conventional description will be omitted.

The control unit 160 is connected to a main control system (not shown) via wireless communication. The main control system controls the processes performed in the factory as a whole and controls the unmanned conveying device 100 in response to the processes. The control unit 160 may be remotely controlled by the main control system.

Basically, by effectively controlling the driving unit 130 and the steering unit 140 required to move the unmanned transport device 100 according to the present embodiment, the unmanned transport device 100 may be moved and finely adjusted. have.

By simply removing the fine drive devices in the conventional unmanned transport device, it is not possible to implement the present invention. This is because, when the fine drive devices are simply removed, fine positioning of the unmanned transport device 100 with respect to the target point cannot be performed. In general, the error range of the unmanned conveying device 100 used in the semiconductor manufacturing process is ± 10 millimeter (mm), ± 1 degree (degree), the unmanned unmanned drive device is removed according to the conventional control method When controlling the conveying device 100, fine positioning of the unmanned conveying device 100 is substantially difficult.

According to this embodiment, the control capability of the control unit 160 is improved to improve the fine driving devices to effectively perform the movement and fine position adjustment of the removed unmanned transport device 100. When the control unit according to the present invention is used in the driving unit 130 and the steering unit 140 having excellent deceleration performance developed to date, the position error range of the unmanned transportation device 100 (± 10 millimeters, ± 1 degree) Can be sufficiently satisfied. By using the driving unit 130 and the steering unit 140 of the unmanned conveying device 100, it is possible to adjust the movement and fine position, thereby miniaturizing the unmanned conveying device 100, reducing manufacturing costs, and ensuring fast and accurate operating performance. Can be obtained. Those skilled in the art will not be able to easily invent a control method that can replace the fine drive devices removed as in this embodiment.

According to the invention, fine drive units can be replaced with main drive units in an unmanned conveying device. Therefore, the size of the unmanned conveying device can be reduced, and the manufacturing cost can be reduced. In addition, by improving the control performance of the main drive unit, it is possible to ensure the operation reliability of the unmanned conveying device, and to perform a fast conveying process.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art various modifications and changes of the present invention without departing from the spirit and scope of the present invention described in the claims below You can. Accordingly, all changes that come within the meaning or range of equivalency of the claims are to be embraced within their scope.

Claims (4)

A vehicle body on which an object is loaded; A driving unit for linearly moving the vehicle body; A steering unit for rotating the vehicle body; Sensing modules emitting a signal toward a positioning mark installed at a target point to check the positioning mark and to sense a distance between the positioning mark and the vehicle body; And And a control unit for controlling the driving unit and the steering unit to move the vehicle body to the target point and to perform fine position correction and posture correction of the vehicle body with respect to the target point according to the separation degree. Unmanned conveying device characterized in that. The vehicle body of claim 1, wherein the vehicle body comprises: a loading unit configured to load and unload the object at the target point by lifting and sliding in a vertical direction; And And a frame part provided with wheels to support the loading part spaced apart from the ground, and a frame part provided with the driving and steering units adjacent to the wheels. The driving unit of claim 1, wherein the driving unit is connected to the wheels, respectively, to rotate the wheels, and the steering unit is connected to the wheels, respectively, to change the rotation ratio of the wheels or to tilt the rotation shafts of the wheels. Unmanned carrier device. The unmanned transportation device of claim 1, wherein the sensing modules are two and are installed at the vehicle body at intervals smaller than the width of the positioning mark.

Images