WO2010002044A1

WO2010002044A1 - Ladder type work-robot

Info

Publication number: WO2010002044A1
Application number: PCT/KR2008/003855
Authority: WO
Inventors: Kyu-Yeul Lee; Jong-Won Kim; Tae-Wan Kim; Dong-Hun Lee; Young-Il Shin; Dong-Hoon Son; Nam-Kug Ku
Original assignee: Seoul National University States Industry Foundation; Daewoo Shipbuilding & Marine Engineering Co., Ltd.
Priority date: 2008-06-30
Filing date: 2008-06-30
Publication date: 2010-01-07

Abstract

The present invention relates to a ladder-type work robot which can perform a work while being vertically lifted and lowered through a plurality of arm members which are slidably connected to each other. The ladder-type work robot, which performs a work in a work space where a plurality of obstacles are disposed, includes a main body that is disposed over a pair of obstacles arranged in parallel to each other, a vertical arm member that is installed in a direction perpendicular to the length direction of the main body, a plurality of sliding arm members that are connected so as to slide in the direction perpendicular to the length direction of the main body, and an attachment arm member having a work robot arm member installed thereon. With a ladder-type structure enabling vertical lifting and lowering, the ladder-type work robot can perform a work in work regions positioned in the upper and lower sides with reference to the height of obstacles. Even when the work robot is designed to have a small height, the work robot can perform a work at a region which is disposed at a high position.

Description

Description LADDER-TYPE WORK ROBOT

Technical Field

[1] The present invention relates to a ladder- type work robot, and more particularly, to a ladder-type work robot which can perform a work while being vertically lifted and lowered by a plurality of arm members which are slidably connected to each other. Background Art

[2] When the bottom or side hull of a ship is damaged, a double hull structure can prevent water from entering the ship. Further, the double hull structure can enhance the strength of the bottom hull and increase space availability. Further, since the center of gravity of the ship is lowered, the stability of the ship is improved.

[3] Because of such advantages of the double hull structure, demand on ships having a double hull structure is increasing recently. However, because the bottom hull of the double hull structure has a complex frame structure, there are difficulties in automating the manufacturing process.

[4] FIG. 1 is a perspective view of an inner bottom block constituting a double hull structure.

[5] As shown in FIG. 1, the inner bottom block 1 constituting a double hull structure has a structure in which a plurality of longis 2 having a T-shaped cross-section are welded on a bottom plate 3 formed of a wide steel plate and are installed in parallel to each other so as to be spaced at a predetermined interval from each other. Further, a web floor 5 and a girder 4 which are formed of a steel plate are installed vertically on the bottom plate 3 so that the inner bottom block 1 as shown in Fig. 1 is constructed.

[6] In general, when the inner bottom block 1 is manufactured, the bottom plate 3, the longis 2, the web floors 5, and the girder 4 are provisionally welded so as to form the entire shape, first. Then, a main welding work is performed. After the shape of the inner bottom block 1 is completed by the provisional welding process, the main welding work is performed between the longis 2 and the web floor 5 and between the bottom plate 3 and the web floor 5, thereby completely manufacturing of the inner bottom block 1.

[7] Further, when the double hull structure is manufactured, a grinding, blasting, or painting work should be performed, in addition to the welding work for the inner bottom block 1.

[8] In particular, the blasting work should be performed on the entire double hull structure, not only at a portion which is positioned at the upper side from the upper end of the longis 2 but also at a portion which is position at the lower side from the upper end of the longis 2.

[9] Conventionally, a crane has been used to position a work device in the vicinity of a work position so as to perform the above-described work. Then, when a work for one portion is completed, the crane is used again to move the work device to another work position so as to perform a work. In this method, however, a crane is needed to perform a work for the inner bottom block 1, and a large number of workers are needed.

[10] FIG. 2 is a perspective view of a double bottom block in which an upper plate is coupled to the inner bottom block shown in FIG. 1.

[11] As shown in FIG. 2, the upper and lower surfaces and the left and right side surfaces of the double bottom block 8 are closed. Therefore, a crane cannot be used for the double bottom block 8. At present, a worker enters the double bottom block 8 and performs a work manually. However, since it is very dark inside the double bottom block 8 and the work is performed in the closed space, the work environment is very poor because of dust, gas and odor produced during grinding, blasting, and painting works.

[12] Therefore, there is a demand for a means by which various works can be performed accurately and safely in a work space having a complex frame structure, such as the entire bottom hull of a double hull structure. Disclosure of Invention

Technical Problem

[13] The present invention has been made in view of the above problems, and it is an object of the present invention to provide a ladder-type work robot which can perform a work in a space where obstacles are installed, such as a double hull structure.

[14] It is another object of the invention to provide a ladder-type work robot which can be vertically lifted and lowered through a plurality of arm members, and, thereby, can effectively and stably perform a work in work regions positioned higher or lower than the obstacles. Technical Solution

[15] In accordance with an aspect of the present invention, the above and other objects can be accomplished by the provision of a ladder-type work robot which performs a work in a work space where a plurality of obstacles are disposed, the ladder-type work robot comprising: a main body that is disposed over a pair of obstacles arranged in parallel to each other; a vertical arm member that is installed in a direction perpendicular to the length direction of the main body; a plurality of sliding arm members that are connected so as to slide in the direction perpendicular to the length direction of the main body; and an attachment arm member having a work robot arm member installed thereon.

[16] The innermost sliding arm member among the plurality of sliding arm members is connected to the vertical arm member so as to slide in the direction perpendicular to the length direction of the main body, the attachment arm member is connected to the outermost sliding arm member so as to slide in the direction perpendicular to the length direction of the main body, and the vertical arm member, the plurality of sliding arm members, and the attachment arm member are connected through a connection member formed in the length direction thereof so as to slide vertically.

[17] The ladder- type work robot further may include a first motor and a pulley that is connected to the first motor so as to be rotated. The vertical arm member and the plurality of sliding arm members may have rollers provided therein, the rollers being rotated in a state where the axial direction thereof is set to the length direction of the main body. The rollers of the respective sliding arm members may be connected to wires which are fixed to the adjacent sliding arm members, the vertical arm member, or the attachment arm member. The roller of the vertical arm member may be connected to a wire which is fixed to the innermost sliding arm member. The wire fixed to the innermost sliding arm member may be connected to the pulley.

[18] The vertical arm member and the sliding arm members may include reinforcement portions.

[19] Each of the reinforcement portions may have a plurality of through-holes formed therein.

[20] The length of the attachment arm member may be set to be smaller than that of the outermost sliding arm member.

[21] The vertical arm member and the plurality of sliding arm members may have the same length.

[22] The sliding wires and the vertical wire may be fixed to the lowermost ends of the sliding arm members, the attachment arm member, and the vertical arm member, and the rollers may be formed at the uppermost ends of the sliding arm members and the vertical arm member.

[23] The work robot arm member may be installed at the lower end of the attachment arm member.

[24] The pulley may have a spiral groove formed thereon.

[25] The ladder-type work robot further may include a link and a second motor that are installed on the main body and the rear surface of the vertical arm member. The vertical arm member may be moved in the length direction of the main body by an operation of the link which is performed when the second motor is driven.

Advantageous Effects [26] The ladder-type work robot according to the invention can perform a work in a place to which a worker cannot have access because the place is closed or where a work risk is high.

[27] With a ladder-type structure which can be lifted and lowered vertically, the ladder- type work robot can perform a work in work regions positioned upper or lower than obstacles. Although the work robot itself is designed to have a small height, the work robot can perform a work at a region which is disposed at a high position.

Brief Description of Drawings [28] The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: [29] FIG. 1 is a perspective view of an inner bottom block constituting a double hull structure; [30] FIG. 2 is a perspective view of a double bottom block in which an upper plate is coupled to the inner bottom block shown in FIG. 1 ; [31] FIG. 3 is a perspective view of a ladder- type work robot 10 according to an embodiment of the invention; [32] FIG. 4 is a cross-sectional view showing the connection relationship between a first sliding arm member 210 and a vertical arm member 200; [33] FIG. 5 is a perspective view of a ladder-type work robot 10 according to another embodiment of the invention; [34] FIG. 6 is a plan view showing the initial position of the ladder- type work robot 10 according to an embodiment of the invention; [35] FIGS. 7 and 8 are plan views showing the work position of the ladder-type work robot 10 according to an embodiment of the invention; [36] FIG. 9 is a partially exploded side view of the ladder-type work robot 10 according to another embodiment of the invention; [37] FIG. 10 is a cross-sectional view of the ladder-type work robot 10 according to another embodiment of the invention; [38] FIG. 11 is a side view showing the initial position of the ladder-type work robot 10 according to another embodiment of the invention; [39] FIG. 12 is a plan view showing a state where arm members of the ladder- type work robot 10 according to another embodiment of the invention are moved upward; [40] FIG. 13 is a conceptual view for explaining the operation of the ladder- type work robot 10 according to another embodiment of the invention; [41] FIG. 14 is a plan view showing a state where the arm members of the ladder- type work robot 10 according to another embodiment of the invention are moved downward;

[42] FIG. 15 is a partial rear view of the ladder- type work robot 10 according to another embodiment of the invention; and

[43] FIG. 16 is a rear perspective view of the ladder-type work robot 10 according to another embodiment of the invention. Best Mode for Carrying out the Invention

[44] Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The invention will be described with reference to exemplary embodiments illustrated in the drawings, but the technical idea and the construction and operation of the invention are not limited to the exemplary embodiments.

[45] FIG. 3 is a perspective view of a ladder-type work robot 10 according to an embodiment of the invention.

[46] Referring to FIG. 3, the ladder- type work robot 10 according to the invention includes a main body 100 which is disposed across the top surfaces of a pair of obstacles 11a and 1 Ib arranged in parallel to each other, a vertical arm member 200 which is installed in a direction perpendicular to the length direction of the main body 100, first through third sliding arm members 210, 220 and 230 which are installed so as to be stacked in a direction perpendicular to the length direction of the main body 100, and an attachment arm member 240 having a work robot arm 300 installed thereon.

[47] The vertical arm member 200 is connected to the main body 100 so as to support the sliding arm members 210, 220 and 230 and the attachment arm member 240. The vertical arm member 200 is installed in such a manner that the first sliding arm member 210 is disposed in a direction perpendicular to the length direction of the main body 100, and the second and third sliding arm members 220 and 230 and the attachment arm member 240 are stacked sequentially.

[48] The attachment arm member 240 has a fixing member 241 installed thereon, and the work robot arm 300 is installed on the fixing member 241. The work robot arm 300 may be selected depending on the type of work such as welding or blasting work. Preferably, a robot arm 300 which can be operated by three shafts is selected.

[49] The first sliding arm member 210 which is the innermost sliding arm member is connected to the vertical arm member 200 so as to slide vertically, and the other sliding arm members 220 and 230 are stacked sequentially so as to be slidably connected to the first sliding arm member 210. The attachment arm member 240 is connected to the third sliding arm member 230, which is the outermost sliding arm member, so as to slide vertically. [50] FIG. 4 is a cross-sectional view showing the connection relationship between the first sliding arm member 210 and the vertical arm member 200.

[51] As shown in FIG. 4, the first sliding arm member 210 and the vertical arm member

200 are slidably connected through a connection member 10. On the rear surface of the first sliding arm member 210, a pin 10a with a dove-tail structure is formed. On the front surface of the vertical arm member 200, a projection 10b having a groove corresponding to the pin 10a is formed. The connection member 10 is formed on the first sliding arm member 210 and the vertical arm member 200 so as to extend in the length direction thereof. While connecting and supporting the first sliding arm member 210 and the vertical arm member 200, the connection member 10 guides the first sliding arm member 210 such that the first sliding arm member 210 slides vertically over the vertical arm member 200.

[52] The connection members 10 are formed symmetrically on the first sliding arm member 210 and the vertical arm member 200. In a space formed between the connection members 10, a unit for vertically moving the first sliding arm member 210 with respect to the vertical arm member 200 may be connected.

[53] The pin 10a comes in contact with the groove of the projection 10b. When the first sliding arm member 210 and the vertical arm member 200 are moved, friction occurs therebetween. Therefore, it is preferable that the contact portions of the pin 10a and the groove of the projection 10b are formed of different materials of which the expansion coefficients are different from each other, such as brass and steel, in order to minimize the friction therebetween.

[54] The second and third sliding arm members 220 and 230 and the attachment arm member 240 are slidably connected to each other in the same manner as the connection manner between the first sliding arm member 210 and the vertical arm member 200. Therefore, detailed descriptions thereof will be omitted.

[55] FIG. 5 is a perspective view of a ladder-type work robot 10 according to another embodiment of the invention.

[56] According to this embodiment, the vertical arm member 200 and the sliding arm members 210, 220 and 230 have reinforcement portions 201, 211, 221 and 231 provided thereon. The vertical arm member 200 and the sliding arm members 210, 220 and 230 having the reinforcement portions 201, 211, 221 and 231 are formed in a box shape of which the top and bottom surfaces are opened. Of the arm members, the vertical arm member 200 has the largest inner cross-sectional area. The cross-sectional area decreases gradually from the vertical arm member 200 to the third sliding arm member 230. The sliding arm members 210, 220 and 230 are housed in the internal spaces of the arm members 200, 210, and 220 connected thereto, respectively. The attachment arm member 240 is housed in the internal space formed by the rein- forcement portion 231 of the third sliding arm member 230. The front surfaces of the respective reinforcement portions 201, 211, 221 and 231 are cut open in such a manner that the vertical motion of the work robot arm 300, which is connected to the front surface of the attachment arm member 240 and extends therefrom, is not interfered with.

[57] When the reinforcement portions are formed on the vertical arm member 200 and the sliding arm members 210, 220 and 230 according to this embodiment, the first sliding arm member 210 connected to the vertical arm member 200 is defined as the innermost sliding arm member, and the third sliding arm member 230 connected to the attachment arm member 240 is defined as the outermost sliding arm member.

[58] The reinforcement portions 201, 211, 221 and 231 serve to enhance the durability of the respective arm members 200, 210, 220 and 230. However, the presence of the reinforcement portions 201, 211, 221 and 231 increases the total weight of the ladder- type work robot 10. Therefore, it is preferable that the reinforcement portions 201, 211, and 221 have a plurality of through-holes 202, 212 and 222 formed therein, respectively.

[59] Hereinafter, the operation of the ladder- type work robot 10 according to an embodiment of the invention will be described referring to FIGS. 6 through 9.

[60] FIG. 6 is a plan view showing the initial position of the ladder- type work robot 10 according to an embodiment of the invention. FIGS. 7 and 8 are plan views showing the work position of the ladder- type work robot 10 according to an embodiment of the invention.

[61] At the initial stage as shown in FIG. 6, the ladder-type work robot 10 according to this embodiment is installed in such a manner that the arm members 200, 210, 220, 230, and 240 overlap with one another. Therefore, even when it is needed to move the work robot arm 300 to a high work position such as the uppermost portion of a web floor 5 (refer to Fig. 1), the vertical arm member 200 itself does not need to be installed to extend to the vicinity of the high work position. Consequently, the overall structure of the robot becomes compact, and the robot can be easily installed in a confined work place.

[62] As shown in FIGS. 7 and 8, the ladder- type work robot 10 according to an embodiment of the invention can perform a work in both upper and lower positions with reference to the height of the obstacles 11a and 1 Ib. That is, the sliding arm members 210, 220 and 230 and the attachment arm member 240 can be controlled in the upward or downward direction so as to move the work robot arm 300 to a desired work position. Even when a work, such as a blasting work, needs to be performed in both the upper and lower positions with reference to the height of the obstacles 11a and 1 Ib, the work can be performed effectively, because the work robot arm 300 can be moved in both the upward and downward directions. [63] The attachment ami member 240 is formed to have a length shorter than that of the third sliding arm member 230. In some cases, the ladder-type work robot 10 may perform a work in a work space of which the top surface is blocked. In this case, as indicated by a dotted line in FIG. 8, when the length of the attachment arm member 240 is set to be equal to or longer than that of the third sliding arm member 230, the upper end of the attachment arm member 240 touches the top surface, so that the work robot 300 is hindered from being moved to a desired work position. In contrast, when the length of the attachment arm member 240 is set to be shorter than that of the third sliding arm member 230, the work robot arm 300 can be moved to the vicinity of the ceiling without any interference. Accordingly, the work region in which the robot can perform a work increases.

[64] The relative upward and downward movement of the arm members with respect to the arm members connected thereto can be controlled by a driving unit, such as a motor, and a link, such as a rack gear. However, to control the upward and downward movement of the respective arm members, a large number of driving units and links should be installed. Therefore, the overall weight of the ladder- type work robot 10 increases, and the structure of the ladder-type work robot 10 becomes complex, which makes it difficult to control the operation of the ladder- type work robot 10.

[65] Therefore, the ladder-type work robot 10 according to another embodiment of the invention controls the relative upward and downward movement between the respective arm members through the pulley mechanism using wires and rollers.

[66] FIG. 9 is a partially exploded side view of the ladder- type work robot 10 according to another embodiment of the invention.

[67] As shown in FIG. 9, the ladder-type work robot 10 includes a first motor 400 fixed to the vertical arm member 200 and a pulley (not shown) connected to the first motor 400. Further, the vertical arm member 200 and the sliding arm members 210, 220 and 230 have rotating rollers 401, 402, 403 and 404 provided therein, respectively.

[68] A first wire 411 is fixed to the pulley connected to the first motor 400, and is fixed to the first sliding arm member 210 via a first roller 401 formed at the vertical arm member 200. A second wire 412 is fixed to the vertical arm member 200, and is fixed to the second sliding arm member 220 via a second roller 402 formed at the first sliding arm member 210. A third wire 413 is fixed to the first sliding arm member 210, and is fixed to the third sliding arm member 230 via a third roller 403 formed at the second sliding arm member 220. A fourth wire 414 is fixed to the second sliding arm member 220, and is fixed to the attachment arm member 240 via a fourth roller 404 formed at the third sliding arm member 230.

[69] FIG. 10 is a cross-sectional view of the ladder-type work robot 10 according to another embodiment of the invention. [70] As shown in FIG. 10, the first through fourth rollers 401, 402, 403 and 404 are installed at the vertical arm member 200 and the sliding arm members 210, 220 and 230, respectively. The first through fourth wires 411, 412, 413 and 414 extend through the space formed by the connection member 10 so as to be connected to the first through fourth rollers 401, 402, 403 and 404, respectively, and are fixed to the corresponding arm members. Since the respective arm members are disposed closely, the wires may be twisted if the first through fourth rollers 401, 402, 403 and 404 are installed in a line. Therefore, as shown in FIG. 10, it is preferable that the rollers are installed in a zigzag shape.

[71] FIG. 11 is a side view showing the initial position of the ladder- type work robot 10 according to another embodiment of the invention. FIG. 12 is a plan view showing a state where the arm members of the ladder- type work robot 10 according to another embodiment of the invention are moved upward. FIG. 13 is a conceptual view for explaining the operation of the ladder- type work robot 10 according to another embodiment of the invention. FIG. 14 is a plan view showing a state where the arm members of the ladder- type work robot 10 according to another embodiment of the invention are moved downward.

[72] At the initial stage, as shown in FIG. 11, the ladder- type work robot 10 according to this embodiment is installed in such a manner that the lower ends of all the arm members 200, 210, 220, 230 and 240 are disposed at the same level.

[73] As shown in FIG. 12, when the first motor 400 rotates at the initial position so as to pull the first wire 411 by a predetermined length such that the first wire 411 is wound around the pulley 420, the first sliding arm member 210 which is connected to the vertical arm member 200 so as to move vertically is moved upward with respect to the vertical arm member 200 by a force applied through the first wire 411. When the first sliding arm member 210 is moved upward, the second sliding arm member 220 is moved upward by the tension of the second wire 412, because the length of the second wire 412 remains constant. In the same way, as shown in FIG. 12, when the first wire 411 is pulled by the rotation of the first motor 400 so as to be wound around the pulley 420, the sliding arm member 210 and the attachment arm member 240 are moved upward.

[74] As shown in FIG. 13, when the radius of the pulley 420 is r and the first motor 400 is rotated by a predetermined angle θ the respective arm members 210, 220, 230 and 240 are lifted by rθ Therefore, the total movement distance of the arm members 210, 220, 230 and 240 is 4rθ.

[75] On the contrary, as shown in FIG. 14, when the first motor 400 is rotated in the reverse direction such that the first wire 411 is unreeled from the pulley 420, all the arm members 210, 220, 230 and 240 descend due to the weight thereof. Therefore, the work robot arm 300 can be moved to a lower position with respect to the height of the obstacle 1 Ia so as to perform a work.

[76] The ladder-type work robot 10 according to this embodiment can control the vertical movement of the arm members 210, 220, 230 and 240 using only one motor. Further, the ladder- type work robot 10 can control the work position of the work robot arm 300 through simple operation.

[77] In the ladder-type work robot 10 according to this embodiment, the respective arm members 210, 220, 230 and 240 are simultaneously moved vertically by the control of one motor. Therefore, the maximum movement distance of the work robot arm 300 from the initial position is determined by the lengths of the vertical arm member 200 and the sliding arm members 210, 220 and 230. That is, assuming that the length of one arm member of the vertical arm member 200 and the sliding arm members 210, 220 and 230 is smaller and it is R, the overall movement distance is limited to 4R. Therefore, it is more effective that the vertical arm member 200 and the sliding arm members 210, 220 and 230 are formed to have the same length, in terms of the structure of the ladder- type work robot 10.

[78] Referring again to FIG. 9, the rollers 401, 402, 403 and 404 are installed on the uppermost ends of the respective arm members 200, 210, 220 and 230, and the wires 411, 412, 413 and 414 are installed on the lowermost ends of the respective arm members 200, 210, 220, 230 and 240. As the rollers 401, 402, 403 and 404 and the wires 411, 412, 413 and 414 are installed in such a manner, the expansion and contraction distance W of the wires 411, 412, 413 and 414 is maximized, which makes it possible to control the movement distance more effectively.

[79] As shown in FIG. 13, the length of the attachment arm member 240 is set to be shorter than that of the third sliding arm member 230. As described above, when the length of the attachment arm member 240 is set to be shorter than that of the third sliding arm member 230, the work region of the work robot arm 300 is enlarged.

[80] The work robot arm 300 is installed so as to be positioned at the lower end of the attachment arm 240. As shown in FIG. 14, when the ladder- type work robot 10 is installed at the initial position, and if the respective arm members 210, 220, 230 and 240 are lowered by rθ by the first motor 400, the lower end of the attachment arm member 240 becomes the lowermost end. When the work robot arm 300 is installed at the upper end of the attachment arm member 240, the work region of the work robot arm 300 may be limited because of the length of the attachment arm member 240. Therefore, to perform an effective work, the work robot arm 300 is installed at the lower end of the attachment arm member 240.

[81] FIG. 15 is a partial rear view of the ladder-type work robot 10 according to another embodiment of the invention. [82] As shown in FIG. 15, the pulley 420 has a spiral groove formed thereon. As the first wire 411 is wound by a predetermined length around the pulley 420 by controlling the rotation angle of the first motor 400, the overall movement distance is controlled. When the wire is wound around the pulley 420 so as to overlap itself, the movement distance depending on the rotation angle of the first motor 400 becomes non-uniform. Therefore, the spiral groove is preferably formed on the surface of the pulley 420 such that the first wire 411 can be wound around the pulley 420 so as not to overlap itself. Then, it is possible to accurately control the movement distance.

[83] FIG. 16 is a rear perspective view of the ladder-type work robot 10 according to another embodiment of the invention.

[84] As shown in FIG. 16, the ladder-type work robot 10 according to this embodiment further includes a second motor 500, and is moved in the length direction of the main body 100 through a link structure such as a rack gear 510.

[85] Therefore, the work can be performed in a wider range since the work robot arm 300 can be moved in the horizontal direction as well. Industrial Applicability

[86] The ladder-type work robot according to the invention can be used in a place which has a complex frame structure such as the bottom hull of a double hull ship, to which an operator cannot have access because the place is closed, or where an operation risk is high. Further, through the ladder-type structure which can be lifted and lowered vertically, the ladder-type work robot can perform a work even in a work area which is positioned in the upper or lower side of an obstacle.

[87] Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims

[1] A ladder- type work robot which performs a work in a work space where a plurality of obstacles are disposed, the ladder-type work robot comprising: a main body that is disposed over a pair of obstacles arranged in parallel to each other; a vertical arm member that is installed in a direction perpendicular to the length direction of the main body; a plurality of sliding arm members that are connected so as to slide in the direction perpendicular to the length direction of the main body; and an attachment arm member having a work robot arm member installed thereon, wherein the innermost sliding arm member among the plurality of sliding arm members is connected to the vertical arm member so as to slide in the direction perpendicular to the length direction of the main body, the attachment arm member is connected to the outermost sliding arm member so as to slide in the direction perpendicular to the length direction of the main body, and the vertical arm member, the plurality of sliding arm members, and the attachment arm member are connected through a connection member formed in the length direction thereof so as to slide vertically.

[2] The ladder- type work robot as set forth in claim 1, further comprising: a first motor; and a pulley that is connected to the first motor so as to be rotated, wherein the vertical arm member and the plurality of sliding arm members have rollers provided therein, the rollers being rotated in a state where the axial direction thereof is set to the length direction of the main body, the rollers of the respective sliding arm members are connected to wires which are fixed to the adjacent sliding arm members, the vertical arm member, or the attachment arm member and extend therefrom, the roller of the vertical arm member is connected to a wire which is fixed to the innermost sliding arm member and extends therefrom, and the wire fixed to the innermost sliding arm member is connected to the pulley.

[3] The ladder-type work robot as set forth in claim 1 or 2, wherein the vertical arm member and the sliding arm members include reinforcement portions.

[4] The ladder- type work robot as set forth in claim 3, wherein each of the reinforcement portions has a plurality of through-holes formed therein.

[5] The ladder-type work robot as set forth in claim 1 or 2, wherein the length of the attachment arm member is set to be shorter than that of the outermost sliding arm member. [6] The ladder-type work robot as set forth in claim 2, wherein the vertical arm member and the plurality of sliding arm members have the same length. [7] The ladder-type work robot as set forth in claim 2, wherein the sliding wires and the vertical wire are fixed to the lowermost ends of the sliding arm members, the attachment arm member, and the vertical arm member, and the rollers are formed at the uppermost ends of the sliding arm members and the vertical arm member. [8] The ladder-type work robot as set forth in claim 2, wherein the work robot arm member is installed at the lower end of the attachment arm member. [9] The ladder-type work robot as set forth in claim 2, wherein the pulley has a spiral groove formed thereon. [10] The ladder-type work robot as set forth in claim 1 or 2 further comprising: a link and a second motor that are installed on the main body and the rear surface of the vertical arm member, wherein the vertical arm member is moved in the length direction of the main body by an operation of the link which is performed when the second motor is driven.