A snake-arm robot having multiple jointed linkages and telescoping degrees of freedom

Abstract

A snake-arm robot with multi-joint linkage and extension / retraction degrees of freedom is disclosed. It includes a drive unit and a snake-arm; the snake-arm includes a base and three structurally identical joints; the drive unit includes a housing, a joint rotation drive module I, and a joint extension / retraction drive module II; the joint rotation drive module I synchronously controls the bending of the three joints; the joint extension / retraction drive module II synchronously controls the extension and retraction of the three joints; four motors cooperate to drive the three joints, achieving linkage between bending and extension / retraction. The advantages of this invention are: a significant reduction in the number of motors while increasing extension / retraction degrees of freedom, expanding the workspace, reducing costs, shrinking the size of the drive unit, and achieving miniaturization and lightweighting of the snake-arm robot; synchronous control of the bending and extension of multiple joints improves the stiffness and precision of the snake-arm; and the linkage-driven operation simplifies the kinematic model and reduces control complexity.

Description

Technical Field

[0001] This invention belongs to the field of robotics technology, specifically relating to a snake-arm robot with multi-joint linkage and extensional degrees of freedom. Background Technology

[0002] Rope-driven snake robots are highly flexible and adaptable robots capable of operating in confined or complex environments, and are currently widely used in fields such as reconnaissance and rescue, pipeline inspection, and space assembly. However, despite their many advantages, existing snake-arm robots also have some drawbacks and challenges that limit their performance and application scope. For example, the snake-like robot disclosed in Chinese patent application CN205254991U has only two bending degrees of freedom per joint, the links cannot extend or retract, and each joint segment requires three motors for drive. The entire snake-like robot requires a large number of drive motors, and the limitation of the number of drive motors results in a short length of the multi-joint snake arm, which restricts the workspace. Chinese patent application CN107053157B proposes a snake-like robotic arm main module and snake-like robotic arm with three degrees of freedom. Springs are used to increase the extension and retraction degrees of freedom and expand the workspace, but its load capacity is limited by the stiffness of the springs, and the extension and retraction are difficult to control precisely. Chinese patent application CN115844321B discloses a medical active continuous endoscope robot. Three motors drive drive ropes through drive wheels with grooves of different diameters to synchronously control multiple continuous bending joints to perform synchronous bending actions, which reduces the number of motors by a factor of two. However, the joint links cannot extend or retract, which restricts the workspace. Summary of the Invention

[0003] To address the aforementioned problems, the present invention aims to provide a snake-arm robot with multi-joint linkage and extensional degrees of freedom.

[0004] To achieve the above objectives, the snake-arm robot with multi-joint linkage and extensional degrees of freedom provided by the present invention includes a drive device and a snake-arm.

[0005] The drive device includes a housing and a joint rotation drive module I and a joint extension drive module II housed within the housing. Three rows of housing guide holes are arranged side-by-side on one side of the housing. The two rows on either side contain three guide holes, and the middle row contains four guide holes, with the top three guide holes at the same height as the three guide holes in the other two rows. The joint rotation drive module I includes a motor, a three-groove reel, and a drive rope. The lower ends of the three motors are fixed side-by-side to the inner front bottom surface of the housing, with their output shafts extending upwards. Each output shaft is equipped with a three-groove reel, and the height of the three grooves on the reel is the same as the height of the top three guide holes in each row of housing guide holes on the housing. The diameter of the grooves increases from top to bottom. Each groove of each three-groove reel has a drive rope wound around it. The outer ends of the three drive ropes on each three-groove reel pass through the three guide holes on the upper part of the corresponding box body and are connected to the corresponding parts on the serpentine arm. The joint telescopic drive module II includes a motor, a single-groove reel, drive ropes, a first telescopic linkage rope, and a second telescopic linkage rope. The lower end of the motor is fixed to the middle of the inner rear bottom surface of the box body. The output axis extends upward and is connected to a single-groove reel. The height of the groove on the single-groove reel is the same as the height of the lowest box guide hole in the middle row of box guide holes on the box body. A drive rope is wound around the groove of the single-groove reel. The outer end of the drive rope passes through the lowest box guide hole in the middle row of box guide holes on the box body and is connected to the corresponding parts on the serpentine arm.

[0006] The serpentine arm includes a base, a first joint, a second joint, and a third joint. The base has a central hole, and its front edge is fixed to the outer side of the housing with a housing guide hole. The outer side of the rear face has three radially arranged base guide holes. The first, second, and third joints have identical structures and are connected to the rear end of the base in a head-to-tail configuration. Each joint includes a sleeve, an end cap, a telescopic rod, a pulley, a universal joint, and a linear bearing. The front end of the sleeve on the first joint is fixed to the center of the rear face of the base. The edge of the end cap is fixed to the rear end of the sleeve, and three linear bearing holes are evenly formed circumferentially on its outer side. A long strip pulley groove and a second rope loop hole are formed through the middle section. A pulley is installed in each pulley groove, and a linear bearing is installed in each linear bearing hole. The telescopic rod includes a front fixed plate, a rear fixed plate, and three guide posts. The front and rear fixed plates are arranged in parallel and each has a central hole. The two ends of the three guide posts are evenly connected to the inner and outer sides of the front and rear fixed plates. The front fixed plate is located inside the sleeve, and its outer edge has a first rope loop hole and a second inner rope hole. Each guide post passes through the central hole of a linear bearing, thus allowing it to slide within the linear bearing and forming a sliding pair. The rear fixed plate is fixed to the front end face of the universal joint. The front and rear ends of the universal joint both have central holes, and the edges have three radially arranged guide holes for the front end face and guide holes for the rear end face, respectively. A first inner rope hole is formed on the outer side of the rear end face. The rear end face of the universal joint on the front joint is connected to the front end of the sleeve on the rear joint.

[0007] The first and second telescopic linkage ropes have the same structure and both consist of an inner rope and a rope loop. The middle part of the inner rope passes through the rope loop, allowing it to slide freely within the loop. One end of the first inner rope on the first telescopic linkage rope is fixed to the inner rope hole on the base, and the other end passes through the second rope loop hole on the end cap of the entire first and second joints, passes around a nearby pulley, and is fixed to the second inner rope hole on the front end face of the telescopic rod. One end of the first rope loop on the first telescopic linkage rope is fixed to the first fixed plate on the front fixing plate of the telescopic rod of the first joint. One end of the second inner rope is fixed to the second rope loop hole on the end cap of the second joint, and the other end is fixed to the second rope loop hole on the end cap of the second joint; one end of the second inner rope on the second telescopic linkage rope is fixed to the first inner rope hole on the universal joint of the first joint, and the other end passes through the second rope loop hole on the end cap of the entire second joint and the third joint, and passes around the nearby pulley before being fixed to the second inner rope hole on the front end face of the telescopic rod; one end of the second rope loop of the second telescopic linkage rope is fixed to the first rope loop hole on the front fixing plate of the telescopic rod of the second joint, and the other end is fixed to the second rope loop hole on the end cap of the third joint.

[0008] The three drive ropes wound around the three grooves of each three-groove reel pass through the box guide hole, the base guide hole, and the universal joint front end guide hole of the corresponding column in a top-to-bottom order, and are then fixed in the three universal joint rear end guide holes at the same radial position on the first joint, the second joint, and the third joint, respectively. The drive rope wound around the single-groove reel passes through the box guide hole of the same height as the groove, then passes around the pulley on the first joint and is fixed in the second inner rope hole of the front fixing plate on the telescopic rod.

[0009] The diameters of the three grooves on the three-groove roller increase in multiples according to the number of joints they pass through.

[0010] Weight reduction holes are formed on the side walls of both the base and the sleeve.

[0011] When the serpentine arm requires more than three joints to move together, increase the number of grooves of different diameters on the reel, the number of drive ropes, and the number of telescopic linkage ropes accordingly.

[0012] The snake-arm robot with multi-joint linkage and extensional degrees of freedom provided by this invention has the following advantages:

[0013] 1. While significantly reducing the number of motors, it increases the degree of freedom of extension and retraction, expands the workspace, reduces costs, and shrinks the size of the drive unit, enabling the miniaturization and lightweighting of snake-arm robots.

[0014] 2. Synchronous control of the bending and extension of multiple joints improves the rigidity and precision of the serpentine arm.

[0015] 3. Driving the snake arm in a linkage manner simplifies the kinematic model and reduces control complexity. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the snake-arm robot with multi-joint linkage and extensional degrees of freedom provided by the present invention.

[0017] Figure 2 This is a schematic diagram of the robotic arm structure in this invention.

[0018] Figure 3 This is a schematic diagram of the internal structure of the box in this invention.

[0019] Figure 4 This is a schematic diagram of the single-joint structure of the present invention.

[0020] Figure 5 This is a schematic diagram of the drive rope connection on the three-groove reel in this invention.

[0021] Figure 6 This is a schematic diagram of the telescopic linkage principle in this invention.

[0022] Figure 7 This is a schematic diagram of the rear end face structure of the end cap in this invention.

[0023] Figure 8 This is a schematic diagram of the front end face structure of the end cap in this invention.

[0024] Figure 9 This is a schematic diagram of the telescopic rod structure in this invention.

[0025] Figure 10 This is a schematic diagram of the universal joint structure in this invention.

[0026] Figure 11 This is a schematic diagram of the first telescopic linkage rope structure in this invention. Detailed Implementation

[0027] The snake-arm robot with multi-joint linkage and extensional degrees of freedom provided by the present invention will be described in detail below with reference to the accompanying drawings.

[0028] like Figure 1 — Figure 11 As shown, the snake-arm robot with multi-joint linkage and extensional degrees of freedom provided by the present invention includes a drive device 1 and a snake arm 2.

[0029] The drive device 1 includes a housing 11 and a joint rotation drive module I and a joint extension drive module II housed within the housing 11. Three rows of housing guide holes 111 are arranged side-by-side on one side of the housing 11. The two rows on either side contain three guide holes 111, and the middle row contains four guide holes 111, with the top three guide holes 111 at the same height as the three guide holes 111 in the other two rows. The joint rotation drive module I includes a motor 12, a three-groove reel 13, and a drive rope 14. The lower ends of the three motors 12 are fixed side-by-side to the inner front bottom surface of the housing 11, with their output shafts extending upwards. Each output shaft is equipped with a three-groove reel 13, and the height of the three grooves on the three-groove reel 13 is the same as the height of the top three guide holes 111 in each row of housing guide holes 111 on the housing 11. The diameter of the grooves increases from top to bottom. Each three-groove reel... Each groove of the wheel 13 is wound with a drive rope 14. The outer ends of the three drive ropes 14 on each three-groove reel 13 pass through the three corresponding upper box guide holes 111 on the box 11 and are connected to the corresponding components on the serpentine arm 2. The joint telescopic drive module II includes a motor 12, a single-groove reel 15, drive ropes 14, a first telescopic linkage rope 16, and a second telescopic linkage rope 17. The lower end of the motor 12 is fixed to the middle of the inner rear bottom surface of the box 11. The output axis extends upward and is connected to a single-groove reel 15. The height of the groove on the single-groove reel 15 is the same as the height of the lowest box guide hole 111 in the middle row of box guide holes 111 on the box 11. A drive rope 14 is wound in the groove of the single-groove reel 15. The outer end of the drive rope 14 passes through the lowest box guide hole 111 in the middle row of box guide holes 111 on the box 11 and is connected to the corresponding components on the serpentine arm 2.

[0030] The serpentine arm 2 includes a base 21, a first joint 22, a second joint 23, and a third joint 24. The base 21 has a central hole, and its front edge is fixed to the outer side of the housing 11, which has a housing guide hole 111. The outer side of the rear end face has three concentric radially arranged base guide holes 212. The first joint 22, the second joint 23, and the third joint 24 have identical structures and are connected sequentially to the rear end of the base 21. Each joint includes a sleeve 25 and an end cap 2. 6. Telescopic rod 27, pulley 28, universal joint 29, and linear bearing 210; the front end of the sleeve 25 on the first joint 22 is fixed to the middle of the rear end face of the base 21; the edge of the end cap 26 is fixed to the rear end of the sleeve 25, and three linear bearing holes 261 are evenly formed circumferentially on the outer part, and a long strip pulley groove 262 and a second rope loop hole 263 are formed through the middle part; a pulley 28 is set in each pulley groove 262; a linear bearing is installed in each linear bearing hole 261. 210; The telescopic rod 27 includes a front fixed plate 274, a rear fixed plate 273, and three guide posts 275; wherein the front fixed plate 274 and the rear fixed plate 273 are arranged in parallel and each has a central hole; the two ends of the three guide posts 275 are evenly connected to the outer sides of the inner surfaces of the front fixed plate 274 and the rear fixed plate 273; the front fixed plate 274 is disposed inside the sleeve 25, and a first rope loop hole 272 and a second inner rope hole 271 are formed on its outer edge; a linear bearing 2 passes through the middle of each guide post 275. The center hole of the 10 allows it to slide within the linear bearing 210, forming a sliding pair; the rear fixing plate 273 is fixed to the front end face of the universal joint 29; the front end face and the rear end face of the universal joint 29 both have a center hole, and the edge portion has three radially evenly arranged universal joint front end face guide holes 293 and universal joint rear end face guide holes 292, respectively, and a first inner rope hole 291 is formed on the outer part of the rear end face; the rear end face of the universal joint 29 on the front joint is connected to the front end of the sleeve 25 on the rear joint;

[0031] The first telescopic linkage rope 16 and the second telescopic linkage rope 17 have the same structure and both consist of an inner rope and a rope sleeve. The middle part of the inner rope passes through the rope sleeve, so it can slide freely inside the rope sleeve. One end of the first inner rope 161 on the first telescopic linkage rope 16 is fixed in the inner rope hole 211 on the base 21, and the other end passes through the second rope sleeve hole 263 on the end cap 26 of the entire first joint 22 and the second joint 23, and passes around the nearby pulley 28 before being fixed in the second inner rope hole 271 on the front end face of the telescopic rod 27. One end of the first rope sleeve 162 on the first telescopic linkage rope 16 is fixed in the first rope sleeve hole 272 on the front fixing plate 274 of the telescopic rod 27 of the first joint 22, and the other end is fixed to the end cap 274 of the second joint 23. The second rope loop hole 263 on the 6 is fixedly connected; one end of the second inner rope 171 on the second telescopic linkage rope 17 is fixedly connected to the first inner rope hole 291 on the universal joint 29 of the first joint 22, and the other end passes through the second rope loop hole 263 on the end cap 26 of the entire second joint 23 and the third joint 24 and passes around the nearby pulley 28 before being fixedly connected to the second inner rope hole 271 on the front end face of the telescopic rod 27; one end of the second rope loop 172 of the second telescopic linkage rope 17 is fixedly connected to the first rope loop hole 272 on the front fixing plate 274 of the telescopic rod 27 of the second joint 23, and the other end is fixedly connected to the second rope loop hole 263 on the end cap 26 of the third joint 24; in addition, the length of the inner rope and the rope loop cannot be compressed or stretched, but can be bent to a limited extent;

[0032] The three drive ropes 14 wound around the three grooves of each three-groove reel 13 pass through the box guide hole 111, the base guide hole 212 and the universal joint front end guide hole 293 of the corresponding column in order from top to bottom, and are then fixed in the three universal joint rear end guide holes 292 at the same radial position on the first joint 22, the second joint 23 and the third joint 24 respectively; the drive rope 14 wound around the single-groove reel 15 passes through the box guide hole 111 of the same height as the groove, and then passes around the pulley 28 on the first joint 22 and is fixed in the second inner rope hole 271 of the front fixing plate 274 on the telescopic rod 27.

[0033] The diameters of the three grooves on the three-groove roller 13 increase in multiples according to the number of joints they pass through.

[0034] Weight reduction holes are formed on the side walls of both the base 21 and the sleeve 25.

[0035] When the serpentine arm 2 requires more than three joints to be linked, the number of grooves of different diameters on the reel, the number of drive ropes 14, and the number of telescopic linkage ropes are increased accordingly. In this way, the serpentine arm 2 can increase the overall degree of freedom and expand the workspace by adding multiple sets of linked joints to meet the work requirements.

[0036] The serpentine arm 2 with three joints is driven by four motors 12. Among them, the three motors 12 of the joint rotation drive module I drive the three-groove reel 13 to stretch nine drive ropes 14, controlling the synchronous bending of the three joints; the one motor 12 of the joint extension drive module II drives the single-groove reel 15 to stretch one drive rope 14, controlling the extension and retraction of the first joint 22, and synchronously driving the first extension linkage rope 16 and the second extension linkage rope 17 to control the extension and retraction of the second joint 23 and the third joint 24.

[0037] The working principle of the snake-arm robot with multi-joint linkage and extension freedom provided by this invention is as follows: When the motor 12 in the joint rotation drive module I drives the three-groove roller 13 to rotate, the three drive ropes 14 on each three-groove roller 13 stretch the universal joints 29 of the first joint 22, the second joint 23, and the third joint 24 in order of increasing diameter of the wound groove, driving the three joints to bend synchronously. When the motor 12 in the joint extension drive module II drives the single-groove roller 15 to rotate, the drive rope 14 on the single-groove roller 15 passes around the pulley 28 on the first joint 22, pulls the guide post 275 on the telescopic rod 27 to slide in the linear bearing 210, driving the first joint 22 to extend; at the same time, the first inner rope 161 between the first rope loop hole 272 on the first joint 22 and the inner rope hole 211 on the base 21 is stretched, the first inner rope 161 slides in the first rope loop 162, driving the first inner rope 161 to pass around the pulley 28 on the second joint 23. Rope 161 pulls the guide post 275 on the telescopic rod 27 to slide in the linear bearing 210, driving the second joint 23 to extend. Simultaneously, the second inner rope 171 between the first rope loop hole 272 of the second joint 23 and the first inner rope hole 291 of the first joint 22 is stretched. The second inner rope 171 slides within the second rope loop 172, driving the second inner rope 171, which passes around the pulley 28 on the third joint 24, to pull the telescopic rod 27 to slide in the linear bearing 210, driving the third joint 24 to extend. This achieves synchronous extension and retraction of the three joints. When the joint extends, the drive rope 14 on the single-groove reel 15 contracts, and the drive rope 14 on the triple-groove reel 13 extends; when the joint shortens, the drive rope 14 on the single-groove reel 15 extends, and the drive rope 14 on the triple-groove reel 13 contracts.

Claims

1. A snake-arm robot having multiple jointed linkages and telescoping degrees of freedom, characterized by: The snake-arm robot with multi-joint linkage and extension freedom includes a drive unit (1) and a snake arm (2); The drive device (1) includes a housing (11) and a joint rotation drive module I and a joint extension drive module II disposed within the housing (11). Three rows of housing guide holes (111) are arranged side-by-side in the middle of one side of the housing (11). The two rows on either side contain three housing guide holes (111), and the middle row contains four housing guide holes (111), with the top three housing guide holes (111) at the same height as the three housing guide holes (111) in the other two rows. The joint rotation drive... Module I includes a motor (12), a three-groove reel (13), and a drive rope (14); the lower ends of the three motors (12) are fixed side by side on the inner front bottom surface of the housing (11), with the output shafts extending upwards. Each output shaft is equipped with a three-groove reel (13), and the height of the three grooves on the three-groove reel (13) is the same as the height of the upper three guide holes (111) in each row of guide holes (111) on the housing (11). The diameter of the grooves increases from top to bottom; each three-groove reel (14) has a diameter of 12. Each groove contains a drive rope (14), and the outer ends of the three drive ropes (14) on each three-groove reel (13) pass through the three corresponding guide holes (111) on the upper part of the housing (11) and are connected to the corresponding parts on the serpentine arm (2); the joint telescopic drive module II includes a motor (12), a single-groove reel (15), drive ropes (14), a first telescopic linkage rope (16), and a second telescopic linkage rope (17); the lower end of the motor (12) is fixed inside the housing (11). At the center of the bottom surface of the part, the output shaft extends upward and is connected to a single groove reel (15), and the height of the groove on the single groove reel (15) is the same as the height of the lowest box guide hole (111) in the middle row of box guide holes (111) on the box body (11); a drive rope (14) is wound in the groove of the single groove reel (15), and the outer end of the drive rope (14) passes through the lowest box guide hole (111) in the middle row of box guide holes (111) on the box body (11) and is connected to the corresponding component on the snake arm (2); The serpentine arm (2) includes a base (21), a first joint (22), a second joint (23), and a third joint (24); the base (21) has a central hole, and its front edge is fixed to the outer side of the box (11) which has a box guide hole (111). The outer side of the rear end has three radially arranged base guide holes (212). The first joint (22), second joint (23), and third joint (24) have the same structure and are connected to the rear end of the base (21) in a head-to-tail manner. Each joint includes a sleeve (25), an end cap (…), and a… 26), telescopic rod (27), pulley (28), universal joint (29), and linear bearing (210); the front end of the sleeve (25) on the first joint (22) is fixed to the middle of the rear end face of the base (21); the edge of the end cap (26) is fixed to the rear end of the sleeve (25), and three linear bearing holes (261) are evenly formed circumferentially on the outer part, and a long strip pulley groove (262) and a second rope loop hole (263) are formed through the middle part; a pulley (28) is set in each pulley groove (262); a linear bearing (28) is installed in each linear bearing hole (261). A linear bearing (210); the telescopic rod (27) includes a front fixed plate (274), a rear fixed plate (273), and three guide posts (275); wherein the front fixed plate (274) and the rear fixed plate (273) are arranged in parallel and each has a central hole; the two ends of the three guide posts (275) are evenly connected to the outer side of the inner side of the front fixed plate (274) and the rear fixed plate (273); the front fixed plate (274) is set inside the sleeve (25), and a first rope loop hole (272) and a second inner rope hole (271) are formed on the outer edge; each guide post (275) has a central hole through which a rope loop hole is formed. It passes through the center hole of a linear bearing (210), so it can slide inside the linear bearing (210) to form a sliding pair; the rear fixing plate (273) is fixed on the front end face of the universal joint (29); the front end face and the rear end face of the universal joint (29) are both formed with a center hole and three radially evenly arranged guide holes (293) and guide holes (292) are formed on the edge, and a first inner rope hole (291) is formed on the outer part of the rear end face; the rear end face of the universal joint (29) on the front joint is connected to the front end of the sleeve (25) on the rear joint; The first telescopic linkage rope (16) and the second telescopic linkage rope (17) have the same structure and are both composed of an inner rope and a rope sleeve. The middle part of the inner rope passes through the rope sleeve, so it can slide freely inside the rope sleeve. One end of the first inner rope (161) on the first telescopic linkage rope (16) is fixed in the inner rope hole (211) on the base (21) and the other end passes through the second rope sleeve hole (263) on the end cap (26) of the entire first joint (22) and the second joint (23) and passes around the nearby pulley (28) before being fixed in the second inner rope hole (271) on the front end face of the telescopic rod (27). One end of the first rope sleeve (162) on the first telescopic linkage rope (16) is fixed in the first rope sleeve hole (272) on the front fixing plate (274) of the telescopic rod (27) of the first joint (22) and the other end is connected to the first inner rope hole (272) on the front fixing plate (274) of the telescopic rod (27) of the first joint (22). The second rope loop hole (263) on the end cap (26) of the second joint (23) is fixedly connected; one end of the second inner rope (171) on the second telescopic linkage rope (17) is fixedly connected to the first inner rope hole (291) on the universal joint (29) of the first joint (22), and the other end passes through the second rope loop hole (263) on the end cap (26) of the entire second joint (23) and the third joint (24) and passes around the nearby pulley (28) before being fixedly connected to the second inner rope hole (271) on the front end face of the telescopic rod (27); one end of the second rope loop (172) of the second telescopic linkage rope (17) is fixedly connected to the first rope loop hole (272) on the front fixing plate (274) of the telescopic rod (27) of the second joint (23), and the other end is fixedly connected to the second rope loop hole (263) on the end cap (26) of the third joint (24); The three drive ropes (14) wound around the three grooves of each three-groove reel (13) pass through the box guide hole (111), the base guide hole (212) and the universal joint front end face guide hole (293) of the corresponding column in order from top to bottom, and are then fixed in the three universal joint rear end face guide holes (292) at the same radial position on the first joint (22), the second joint (23) and the third joint (24), respectively. The drive rope (14) wound around the single-groove reel (15) passes through the box guide hole (111) of the same height as the groove, and then passes around the pulley (28) on the first joint (22) and is fixed in the second inner rope hole (271) of the front fixing plate (274) on the telescopic rod (27).

2. The snake-arm robot with multiple jointed linkage and telescopic degrees of freedom according to claim 1, characterized in that: The diameters of the three grooves on the three-groove roller (13) increase from top to bottom according to the number of joints they pass through.

3. The snake-arm robot with multiple jointed linkage and telescopic degrees of freedom according to claim 1, characterized in that: Weight reduction holes are formed on the side walls of both the base (21) and the sleeve (25).

4. The snake-arm robot with multiple jointed linkage and telescopic degrees of freedom according to claim 1, characterized in that: When the serpentine arm (2) requires more than three joints to move together, increase the number of grooves of different diameters on the reel, the number of drive ropes (14), and the number of telescopic linkage ropes accordingly.

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