A multi-degree-of-freedom rope-driven continuum robot

Abstract

The application discloses a multi-degree-of-freedom rope-driven continuum robot, which comprises a driving box, a mechanical arm and a plurality of driving ropes; the driving box is provided with a plurality of driving units, each driving unit drives one of the driving ropes to realize relaxation and tension of the driving ropes; the mechanical arm comprises a mechanical arm extension rod, a plurality of interval discs and a load end interval disc, and at least one through hole is arranged at each corner of the mechanical arm; four ropes are a group, one end of the four ropes is fixed on the corresponding driving unit, and the four ropes pass through the through holes at the corners in sequence, and the other end of the four ropes is fixed on the end structure of the motion segment; the continuum robot adopts a single-motion-segment four-driving-rope configuration, has good bearing capacity and control precision; and the continuum robot adopts a rigid-flexible hybrid configuration mechanical arm design, has higher rigidity compared with a pure flexible configuration, and has better flexibility compared with a pure rigid configuration.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of robots, in particular to a multi-degree-of-freedom rope-driven continuum robot. BACKGROUND

[0002] In recent years, with the progress of computer science, materials and manufacturing technology, more and more bio-inspired designs have been realized, and continuum robots are one of them, which are inspired by snakes. Continuum robots have a compliant backbone that can be continuously bent, and the position and direction of the backbone curve and the backbone end can be adjusted as needed, and can be controlled by internal drivers (such as pneumatic or hydraulic) or transmission elements (such as ropes, rods) pushed / pulled from the backbone end. These robots have a flexible body with a high length-diameter ratio, which is very suitable for performing tasks that require tools or sensors to be extended into tortuous and narrow paths. Continuum robots have a wide range of applications, including medical, manufacturing, aerospace, search and rescue, and nuclear energy, and in these application scenarios, continuum robots can be used to inspect and intervene in areas that traditional robots cannot enter.

[0003] Rope driving is one of the mainstream driving schemes for continuum robots. However, when faced with limited space and narrow paths, traditional rope-driven continuum robots often use circular cross-section pure flexible configurations to ensure high flexibility and low cross-sectional area. Although this structure has relatively high compliance, the mechanical arm has poor load capacity, and the mechanical arm end cannot carry a large load. At the same time, the pure flexible configuration of the mechanical arm lacks rigid connection and cannot provide the stability required for precise control of the mechanical arm end pose.

[0004] In addition, in order to reduce the number of rope driving motors as much as possible, existing rope-driven continuum robots usually provide each motion segment with multi-degree-of-freedom motion capability with 3 driving ropes. However, compared to more driving rope configurations, the load capacity of the 3 driving rope configuration motion segment will be reduced, and the response of the mechanical arm to external disturbances will be greater, and the control accuracy may decrease. Too many driving ropes for a single motion segment will also introduce problems, such as more complex control strategies, more driving motors required, which will consume more computing resources, power resources and space resources, etc. SUMMARY

[0005] The present application aims to overcome the shortcomings of the prior art and provides a multi-degree-of-freedom rope-driven continuum robot, which adopts a more reasonable mechanical arm cross-sectional shape design, mechanical arm configuration design and motion segment driving rope quantity configuration, and a corresponding pose control strategy, thereby realizing stronger load capacity, higher pose accuracy and better external disturbance resistance in the case of ensuring less occupied space, high flexibility and relatively fewer required motors.

[0006] The object of the present application is achieved by the technical solutions as follows: a multi-degree-of-freedom rope-driven continuum robot, comprising a driving box, a mechanical arm and a plurality of driving ropes; the driving box is provided with a plurality of driving units, each of which drives the winding and unwinding of one of the driving ropes;

[0007] The mechanical arm comprises a mechanical arm extension rod, a plurality of interval discs and a load end interval disc, and they are connected in series; the mechanical arm comprises at least one action segment, which is composed of a plurality of series-connected interval discs or a plurality of series-connected interval discs and a load end interval disc; the mechanical arm extension rod, the plurality of interval discs and the load end interval disc are each provided with at least one through hole at the four corners; every four ropes form a group, one end of which is fixed on the corresponding driving unit and sequentially passes through the through holes at the four corners, and the other end is fixed on the terminal structure of the action segment;

[0008] One end of the mechanical arm extension rod is fixed on the driving box; the inner side wall of the other end is oppositely provided with two pin holes; the outer side wall of the other end is symmetrically provided with a groove; the four inner side walls of the interval disc are symmetrically provided with pin holes, and the two opposite outer side walls are each provided with a shaft at one end for installing a bearing, and the other two opposite outer side walls are each provided with a groove at the other end; the inner side walls of the load end interval disc are oppositely provided with two pin holes, and the outer side walls are each oppositely provided with a shaft for installing a bearing;

[0009] For the series connection between two adjacent interval discs, one end of each of the two flexible metal rods is respectively inserted into the opposite pin holes of one of the interval discs, and the other end is respectively inserted into the opposite pin holes of the other interval disc, forming a flexible connection; the lower part of the bearing seat is installed on the groove of one of the interval discs, and the upper part of the bearing seat is provided with a limiting groove matched with the outer ring of the bearing installed on the other interval disc, forming a rotary joint; the adjacent mechanical arm extension rod and interval disc, and the adjacent interval disc and load end interval disc are connected in series in the same way.

[0010] Further, every four ropes form a group, one end of which is fixed on the corresponding driving unit and sequentially passes through the through holes at the four corners, and the other end is fixed on the terminal structure of the action segment, to realize the following movements:

[0011] Controlling the tightening or loosening of the two driving ropes on the left side and the loosening or tightening of the two driving ropes on the right side realizes the yaw movement of the mechanical arm, and controlling the tightening or loosening of the two driving ropes on the lower side and the loosening or tightening of the two driving ropes on the upper side realizes the pitch movement of the mechanical arm.

[0012] Further, the driving box comprises a spliced frame, a plurality of driving units, a plurality of motor dual-purpose wiring boards, a main stem side wiring board and a mechanical arm adapter plate; the spliced frame is divided into an inner frame and an outer frame, the inner frame is fixed in the outer frame, the plurality of driving units, the plurality of motor dual-purpose wiring boards and the main stem side wiring board are fixed on the inner frame, and the mechanical arm adapter plate is fixed on the outer frame; each driving unit corresponds to a motor dual-purpose wiring board;

[0013] Further, every four ropes form a group, which corresponds to four driving units, two of which are installed on one side of the inner frame, and the other two are installed on the other side of the inner frame; the driving units on the same side and adjacent to each other have opposite rotation directions of the driving ropes.

[0014] Further, the driving unit comprises a brushless motor back plate, a brushless motor and a driving rope winch; the brushless motor back plate is used for fixing the brushless motor; the brushless motor is fixed with the driving rope winch, one end of the driving rope is fixed on the driving rope winch to drive the driving rope winch to rotate, so as to relax and tighten the driving rope;

[0015] Two notches are reserved on the radial outer side of the driving rope winch, each driving unit is provided with a manual winding wrench, the internal protrusion of the manual winding wrench is engaged with the notch of the driving rope winch, so as to realize manual winding and manual debugging.

[0016] Further, the motor dual-purpose wiring board comprises a wiring board body, a first soft pipe straight-through quick connector and a soft pipe; the first soft pipe straight-through quick connector is fixed on the wiring board body;

[0017] The main stem side wiring board comprises a wiring board body and a plurality of second soft pipe straight-through quick connectors, the number of the second soft pipe straight-through quick connectors is consistent with the number of the motor dual-purpose wiring boards, one end of the soft pipe is inserted into the first soft pipe straight-through quick connector, and the other end is inserted into the second soft pipe straight-through quick connector, so as to form a channel of the driving rope;

[0018] The mechanical arm adapter plate comprises an adapter plate body and four fastening screws, each side surface of the adapter plate body is provided with a threaded hole, and the center is hollow, for installing a mechanical arm extension rod; the four fastening screws are uniformly and symmetrically distributed on the four side surfaces of the adapter plate body, and the coaxiality adjustment of the central shaft of the mechanical arm extension rod and the central shaft of the mechanical arm adapter plate is realized by screwing and unscrewing the two opposite screws.

[0019] Further, the cross section of the mechanical arm is rectangular, and the center region is hollow, for passing through a mechanical arm end sensor wire harness.

[0020] Further, the load end spacer disc comprises a spacer disc body and a detachable load carrier; the inner side wall of the spacer disc body is provided with two pin holes opposite to each other, and the outer side wall is provided with a shaft opposite to each other, which is used for installing a bearing; the central region of the spacer disc body is hollow, which is used for loading the detachable load carrier.

[0021] Further, the installation of the spacer disc body and the detachable load carrier adopts a Snap-Fit design, two opposite sides of the spacer disc body are provided with through holes, and the detachable load carrier can be installed by pushing the head of the spacer disc body; when disassembling, the detachable load carrier can be taken out by inserting a clamping needle into the side through hole of the spacer disc body.

[0022] Further, one end of the mechanical arm extension rod connected with the spacer disc is a bevel, both ends of the spacer disc are bevels, one end of the load end spacer disc connected with the spacer disc is a bevel, and the inclination angles of all the bevels are consistent, and the symmetric n° included angle is formed between the two adjacent end bevels; the number of the spacer disc and the load end spacer disc is 2x180 / n, so that the maximum pitch angle and the maximum yaw angle of the mechanical arm end are both 180°.

[0023] The beneficial effects of the present application are that, compared with other rope-driven continuum robots, the multi-degree-of-freedom continuum robot provided by the present application adopts a single-action segment four-drive rope configuration and a posture control strategy, and has better pose accuracy and carrying capacity. The continuum robot provided by the present application adopts a unique rectangular cross-section mechanical arm design, and compared with a circular cross-section, has a smaller cross-sectional area under the condition that the radial spacing of the opposite driving ropes is unchanged, and the mechanical arm occupies less space, thereby having better passability and space utilization in a limited space. The continuum robot provided by the present application adopts a rigid-flexible hybrid configuration mechanical arm design, and compared with a pure flexible configuration, has higher rigidity, and compared with a pure rigid configuration, has better flexibility. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application.

[0025] Figure 1 A multi-degree-of-freedom rope-driven continuum robot structure schematic diagram provided for the embodiments of the present application.

[0026] Figure 2 A drive box structure schematic diagram provided for the embodiments of the present application.

[0027] Figure 3 A drive unit structure schematic diagram provided for the embodiments of the present application.

[0028] Figure 4 A schematic diagram of a motor side dual-purpose wiring board and backbone side wiring board structure is provided for an embodiment of the present application.

[0029] Figure 5 A schematic diagram of a mechanical arm adapter plate structure is provided for an embodiment of the present application.

[0030] Figure 6 A schematic diagram of a rigid-flexible hybrid configuration mechanical arm structure with a rectangular cross section is provided for an embodiment of the present application.

[0031] Figure 7 A schematic diagram of a mechanical arm segment division is provided for an embodiment of the present application.

[0032] Figure 8 A schematic diagram of a mechanical arm extension rod structure is provided for an embodiment of the present application.

[0033] Figure 9 A schematic diagram of the connection between an immovable segment and a movable segment is provided for an embodiment of the present application.

[0034] Figure 10 A schematic diagram of a spacer disc structure is provided for an embodiment of the present application.

[0035] Figure 11 A schematic diagram of a spacer disc arrangement is provided for an embodiment of the present application.

[0036] Figure 12 A schematic diagram of the connection of a spacer disc is provided for an embodiment of the present application.

[0037] Figure 13 A schematic diagram of a load end spacer disc structure is provided for an embodiment of the present application.

[0038] Figure 14 A schematic diagram of the installation and removal of a load carrier is provided for an embodiment of the present application.

[0039] Figure 15 A schematic diagram of the range of variation of the included angle between adjacent spacer discs is provided for an embodiment of the present application.

[0040] Figure 16 A schematic diagram of the maximum deflection angle of a mechanical arm is provided for an embodiment of the present application.

[0041] Figure 17 A schematic diagram of the arrangement and grouping of drive units is provided for an embodiment of the present application.

[0042] Figure 18 A schematic diagram of the take-up direction of a drive unit is provided for an embodiment of the present application.

[0043] Figure 19An action segment control schematic diagram provided for the embodiment of the present application.

[0044] Figure 20 A multi-degree-of-freedom rope-driven continuum robot motion schematic diagram provided for the embodiment of the present application. DETAILED DESCRIPTION

[0045] The exemplary embodiments will be described in detail herein with reference to the attached drawings. In the following description, unless otherwise indicated, like numbers in the attached drawings refer to the same or similar elements. The following detailed description includes specific details for the purpose of providing a thorough understanding of the exemplary embodiments. However, it will be apparent to those skilled in the art that the exemplary embodiments can be practiced without these specific details. In some instances, well-known structures and components are not described in detail in order to avoid obscuring the understanding of the present description.

[0046] The terminology used in the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0047] It is to be understood that the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. It is to be understood that the term "and / or" as used herein encompasses all possible combinations of particular items listed apart from disjunctively one from another by using such terms and permits a selection of one or more claimed features by a claim limitation.

[0048] In addition, the terms "front", "back", "up", "down", "left", "right" are based on the orientation and positional relationship shown in the drawings, and are only for the convenience of describing the present application, and do not indicate that the device or component referred to must have a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0049] The present application will be described in detail below with reference to the accompanying drawings. The features of the embodiments and implementation modes described below can be combined with each other without conflict.

[0050] The continuum robot proposed by the present application is composed of three parts: a drive box 1, a mechanical arm 2, and a drive rope 3. Figure 1 and Figure 20As shown, the drive box 1 is a driving mechanism, the mechanical arm 2 is an executing mechanism, and the driving rope 3 is a power (motion) transmission mechanism. The drive box 1 pulls the driving rope 3 through the movement of the motor inside the drive box 1, and then pulls the mechanical arm 2 to generate movement and pose transformation. The following is a detailed implementation scheme:

[0051] The embodiment of the present application provides a multi-degree-of-freedom rope-driven continuum robot, which comprises a drive box 1, a mechanical arm 2 and a plurality of driving ropes 3; the drive box 1 is provided with a plurality of driving units 12, each driving unit 12 drives one of the driving ropes 3 to realize the relaxation and tension of the driving rope 3;

[0052] The mechanical arm 2 comprises a mechanical arm extension rod 21, a plurality of interval discs 22 and a load end interval disc 23, and they are connected in series; the mechanical arm 2 comprises at least one action segment, and the action segment is composed of a plurality of series-connected interval discs 22 or a plurality of series-connected interval discs 22 and the load end interval disc 23;

[0053] The mechanical arm extension rod 21, the plurality of interval discs 22 and the load end interval disc 23 are provided with at least one through hole at four corners; every four ropes form a group, one end of the group is fixed on the corresponding driving unit 12 and sequentially passes through the through holes at the four corners, and the other end is fixed on the terminal structure of the action segment;

[0054] One end of the mechanical arm extension rod 21 is fixed on the drive box 1; the inner side wall of the other end is oppositely provided with two pin holes, one end of two flexible metal rods is respectively inserted into the pin holes, and the other end is respectively inserted into the pin holes of the adjacent interval disc 22 to form a flexible connection; the outer side wall of the other end is symmetrically provided with a groove; the four inner side walls of the interval disc 22 are symmetrically provided with pin holes, two opposite outer side walls are provided with shafts at one end for installing bearings, and the other two opposite outer side walls are provided with grooves at the other end; the inner side walls of the load end interval disc 23 are oppositely provided with two pin holes, and the outer side walls are oppositely provided with shafts for installing bearings;

[0055] For the series connection between two adjacent interval discs 22, one end of the two flexible metal rods is respectively inserted into the opposite pin holes of one of the interval discs 22, and the other end is respectively inserted into the opposite pin holes of the other interval disc 22 to form a flexible connection; the lower part of the bearing seat is installed on the groove of one of the interval discs 22, and the upper part of the bearing seat is provided with a limiting groove matched with the outer ring of the bearing installed on the other interval disc 22 to form a rotary joint; the adjacent mechanical arm extension rod 21 and interval disc 22 and the adjacent interval disc 22 and load end interval disc 23 are connected in series in the same way.

[0056] The drive box 1 is composed of a spliced frame 11, eight drive units 12, eight motor dual-purpose wiring boards 13, a main stem side wiring board 14, and a mechanical arm adapter plate 15, as shown in Figure 2 The spliced frame 11 is divided into an inner frame 111 and an outer frame 112, the inner frame 111 is fixed in the outer frame 112 by connecting pieces and screws; the drive units 12, the motor dual-purpose wiring boards 13, and the main stem side wiring board are fixed on the inner frame 111 by screws, and the inner frame 111 reserves installation space for the electrical circuits of the drive units and other possible integrated components or sensors; the mechanical arm adapter plate 15 is fixed on the outer frame 112 by screws, and the outer frame 112 also provides impact protection and collision protection for the components in the drive box, and reserves installation interfaces for other systems that may be integrated by the continuum robot. The sizes of the inner frame 111 and the outer frame 112 can be flexibly adjusted to adapt to different motor sizes, motor quantities, and motor arrangement modes.

[0057] The drive unit 12 is composed of a brushless motor back plate 121, a brushless motor 122, and a drive rope winch 123, as shown in Figure 3 The drive rope winch 123 is fixed on the brushless motor 122 by screws, used for fixing and winding the drive rope 3 and converting the rotary motion of the brushless motor 122 into the linear motion of the drive rope 3, the brushless motor 122 is used to provide tension for the drive rope 3 and rotate a specified angle according to the control instruction, thereby tightening or relaxing the drive rope 3 by a specified length; then the brushless motor 122 is fixed on the brushless motor back plate 121 by screws to form the drive unit 12, and the brushless motor back plate 121 is fixed on the inner frame 111. The center of the brushless motor back plate 121 is hollow, and the outside is reserved with an opening, the hollow is convenient for heat dissipation of the brushless motor 122, and the opening is used for quick plugging of the cable of the brushless motor 122. The drive rope winch 123 is reserved with two openings on the radial outside, which is convenient for disassembly and debugging with a screwdriver or wrench; a radial through hole is reserved at the bottom for fixing the drive rope 3. In addition, each drive unit 12 is equipped with a manual winding wrench 124, the internal protrusion of the manual winding wrench 124 can engage with the opening of the drive rope winch 123 to realize manual winding and manual debugging.

[0058] The motor dual-purpose wiring board 13 is composed of a wiring board body 131, a first soft tube straight-through quick plug 132, and a soft tube 133, as shown in Figure 4As shown. The wiring board body 131 adopts a "U"-shaped design. An opening on the left side is used for connection with the inner frame 111, while the right side is suspended and has two rectangular holes for fixing the wiring harnesses of the near-end and far-end brushless motors 122, respectively. Braided reinforcing ribs are provided on both the front and rear sides of the wiring board body 131. The density of the reinforcing ribs decreases in the central area to provide space for the first flexible hose quick-connect plug 132 and the flexible hose 133. The first flexible hose quick-connect plug 132 has a built-in thread, and the wiring board body 131 has a pre-drilled threaded hole to lock the first flexible hose quick-connect plug 132 onto the wiring board body 131. The first flexible hose quick-connect plug 132 has a self-locking function; simply inserting the flexible hose 133 into the first flexible hose quick-connect plug 132 secures it. The wiring board body is used to install the first flexible hose quick connector 132 and provide wire holes for the electrical wiring of the drive unit; the first flexible hose quick connector 132 is used to install and fix the flexible hose 133; the flexible hose 133 is used to regulate the movement path of the drive rope 3, prevent the drive rope from getting tangled with each other, and avoid interference between the drive rope and other components in the drive box.

[0059] For example, the backbone wiring board 14 consists of a wiring board body 141 and eight second flexible straight-through quick connectors 142, such as... Figure 4 As shown. The wiring board body 141 adopts an "I"-shaped design with four through holes on the outside for connection with the inner frame 111; the central area is hollowed out for the passage of the sensor harness at the end of the robotic arm 2; similarly, braided reinforcing ribs are arranged on the front and rear sides. Eight second flexible hose quick-connect plugs 142 are screwed into the eight threaded holes reserved in the wiring board body 141 to form the main side wiring board 14. One end of the flexible hose 133 is inserted into the first flexible hose quick-connect plug 132, and the other end is inserted into the second flexible hose quick-connect plug 142 to form a channel for the drive rope 3.

[0060] For example, each drive unit 12 in the drive box 1 corresponds to a drive rope 3, which is responsible for loosening or tightening the drive rope; each motor-side dual-purpose wiring board 13 corresponds to a drive unit 12, which is responsible for controlling the activity space of the wiring harness of the corresponding drive unit within a limited range and for regulating the movement path of the corresponding drive rope.

[0061] For example, the robotic arm adapter plate 15 consists of an adapter plate body 151 and four fastening screws 152, as shown below. Figure 5The adapter plate body 151 is approximately rectangular in axial cross-section, matching the rectangular cross-section design of the mechanical arm 2. The adapter plate body 151 has multiple through-holes on the tail side for connection with the outer frame 112; a threaded through-hole on each of the four side faces for mounting the fastening screws 152; a hollow center for mounting the mechanical arm extension rod 21 and passing the sensor wire harness; and two reinforcing ribs on each side face to increase structural strength. The four fastening screws 152 are evenly and symmetrically distributed on the four side faces of the adapter plate body 151, and the coaxiality adjustment of the center axis of the mechanical arm extension rod 21 and the center axis of the mechanical arm adapter plate 15 is achieved by screwing in and out of the two opposite screws.

[0062] For example, the mechanical arm 2 is composed of a mechanical arm extension rod 21, seventeen spacer discs 22, and a load end spacer disc 23, as shown in Figure 6 Functionally, the mechanical arm 2 is composed of one non-movable segment and two action segments, as shown in Figure 7 The non-movable segment is the mechanical arm extension rod 21, which is fixed at the tail to the mechanical arm adapter plate 15 and connected at the head to the action segments. The action segments are connected by a certain number of spacer discs, and the mechanical arm 2 contains a total of eighteen spacer discs, divided into two action segments. The first action segment contains nine spacer discs 22, and the second action segment contains eight spacer discs 22 and one load end spacer disc 23.

[0063] For example, the mechanical arm extension rod 21 is composed of an extension rod body 211, two extension rod bearing seats 212, and two first set screws 213, as shown in Figure 8 The extension rod body 211 has eight small-diameter round holes distributed on the outer side of both the head and tail ends for passing the driving rope 3; the center region is hollow with a rectangular cross-section for passing the wire or pipeline of the mechanical arm end sensor or other components; the four side faces have trapezoidal hollows for easy pipeline heat dissipation and observation, and diagonal connecting beams are arranged between adjacent side faces to improve the structural bending and torsion resistance; and two pin holes are arranged on the side wall of the center region opposite to each other, facing the head, for forming a flexible connection with the flexible metal rods 225 of the action segment spacer discs 22. The extension rod bearing seat 212 has a rectangular boss on the lower part with a threaded through-hole on the side face; and a limiting groove with a shoulder on the upper part. The action segment spacer disc 22 with the flexible metal rods 225 and the first bearing 222 is connected to the head of the extension rod body 211, the extension rod bearing seat 212 is installed and the first set screw 213 is tightened, completing the connection between the non-movable segment and the action segment, as shown in Figure 9

[0064] For example, the spacer disc 22 is composed of a spacer disc body 221, two first bearings 222, two bearing seats 223, two second set screws 224, and two flexible metal rods 225, as shown in Figure 10 ​The spacer disc body 221 is rectangular in cross-sectional shape, with beveled ends for limiting function. Eight small-diameter holes are distributed on the outer side of both ends, for passing through the driving rope 3. The central region is hollow, for constraining the cables or pipelines of the end sensor or other components of the mechanical arm. Four pin holes are arranged on the side wall of the central region, with two opposite pin holes facing the head and the other two opposite pin holes facing the tail end, for installing the flexible metal rods 225. The spacer disc body 221 has four sides, two opposite sides at the tail end are equipped with shafts for installing the first bearings 222. The side with the shafts is arranged with X-shaped reinforcing ribs to reduce the weight and increase the structural strength of the spacer disc. The periphery of the reinforcing ribs is asymmetrically shaped to facilitate identification of the installation direction of the spacer disc. The other two sides are equipped with rectangular grooves with threaded blind holes in the center for installing the bearing seats 223 and the set screws 224. The lower part of the bearing seat 223 is a rectangular boss with a chamfered through hole on the back, and the upper part is a bearing limiting groove with a shoulder.

[0065] As shown in Figure 11 each motion segment is composed of multiple spacer discs through rigid connection and flexible connection. Adjacent spacer discs are arranged orthogonally, i.e. each spacer disc is rotated by 90° along the central axis of the mechanical arm relative to the previous spacer disc. As shown in Figure 12 one end of each flexible metal rod 225 is installed into the two pin holes at the tail end of the body 221, and the other end of each flexible metal rod 225 is installed into the two pin holes at the head of the previous body 221, forming the flexible connection between adjacent spacer discs. Two first bearings 222 are installed into the two shafts at the tail end of the body 221, and the lower boss of the two bearing seats 223 is installed into the rectangular groove of the previous body 221, so that the upper limiting groove of the bearing seat 223 cooperates with the outer ring of the first bearing 222, and the second set screw 224 is locked, forming the rotational joint between adjacent spacer discs, i.e. rigid connection. Nine spacer discs 22 are connected in series in the above manner to form the first motion segment of the mechanical arm, and eight spacer discs 22 and one load end spacer disc 23 are connected in series in the above manner to form the second motion segment of the mechanical arm.

[0066] As an example, the load end spacer disc 23 is composed of a spacer disc body 231, two second bearings 232, and a detachable load mounting device 233. The load end spacer disc 23 adds a load mounting function based on the spacer disc 22, realizing the quick disassembly and assembly of different loads, components or sensors. As shown in Figure 13As shown, the spacer disc body 231 is rectangular in cross-sectional shape, with a beveled tail end and a flat head end. Eight small-diameter round holes are distributed on the outer sides of both the head and tail ends, for passing through the drive ropes 3. The central region is hollow, for accommodating the detachable load carrier 233. Two pin holes are arranged on the side wall of the central region, facing the tail end. The body 231 has four side faces, two of which are equipped with shafts at the tail end for mounting the second bearing 232. The other two side faces are open for disassembling the load carrier 233. The detachable load carrier 233 has four side faces, each of which is provided with a groove for positioning and mounting. Depending on the task requirements or the type of load, the structure of the central region of the load carrier 233 can be adaptively designed, which is not described here. As shown, Figure 14 As shown, the installation of the spacer disc body 231 and the load carrier 233 adopts a Snap-Fit design, which can be completed by pushing the load carrier 233 into the head end of the spacer disc body 231. When disassembling, a SIM card needle or other tools can be inserted into the side hole of the spacer disc body 231 to remove the load carrier 233.

[0067] As shown, Figure 15 As shown, the head and tail ends of the spacer disc 22 are beveled, and when the mechanical arm is not in action, the adjacent two spacer discs form a symmetrical 20° angle. The size of the angle can be adjusted by changing the inclination angle of the bevel of the spacer disc 22 according to the use requirements. When the bevels of adjacent spacer discs are in contact, a limit is formed, and the action segment cannot continue to act. The spacer discs are arranged orthogonally, so that between every three series of spacer discs, two groups of angles are formed, which have the ability to pitch and yaw. There are 18 groups of orthogonally arranged angles between the extension rod 21, the seventeen spacer discs 22, and the load end spacer disc 23, and the change range of the angles is 0° to 40°. Therefore, the maximum pitch angle and the maximum yaw angle of the end of the mechanical arm 2 are both 180°, as shown, Figure 16 As shown.

[0068] The drive ropes 3 are made of high-strength high-modulus, low-creep, wear-resistant and high-temperature-resistant materials, which are used to transmit the power generated by the drive motor to the mechanical arm action segment. As an example, there are eight drive ropes 3, four of which are connected to the four corners of the spacer disc 22 at the end of the first action segment, and the other four are connected to the four drive units in the first group of drive units. The other four ropes are connected to the four corners of the load end spacer disc 23 at the end of the second action segment, and the other four are connected to the four drive units in the second group of drive units. The control strategy of the mechanical arm action segment is as follows:

[0069] As shown, Figure 17As shown, the eight drive units 12 in the drive box 1 are divided into two groups, four in each group. The four drive units 12 at the rear end of the drive box 1 are responsible for controlling the first action segment of the mechanical arm 2, and the four drive units 12 at the front end of the drive box 1 are responsible for controlling the second action segment of the mechanical arm 2. The front and rear spacing of each drive unit 12 is consistent, and they are evenly distributed on the inner frame 111. In order to avoid the drive unit 12 generating excessive same direction torque when the mechanical arm is rapidly maneuvered in some postures, the take-up rotation direction of the brushless motor 122 of the drive units 12 located on the same side of the inner frame 111 and adjacent to each other is opposite, as shown. Figure 18

[0070] Taking the second action segment as an example, when the left two drive units take up the wire and the right two drive units pay out the wire, the action segment performs left bias action; when the left two drive units pay out the wire and the right two drive units take up the wire, the action segment performs right bias action; when the front two drive units take up the wire and the rear two drive units pay out the wire, the action segment performs lifting action; when the front two drive units pay out the wire and the rear two drive units take up the wire, the action segment performs lowering action, as shown. Figure 19 Since each drive rope is independently controlled by a drive unit, the two action segments can achieve decoupling of actions.

[0071] Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. It is intended that the application be limited only by the scope of the claims, including any appropriate equivalents. The specification and examples are to be construed as merely exemplary and not limiting of the scope of the application.

[0072] It should be understood that the application is not limited to the precise construction that has been described above and illustrated in the accompanying drawings, and that various modifications and changes can be made by those skilled in the art without departing from the scope of the application.​

Claims

1. A multi-degree-of-freedom rope-driven continuum robot, characterized in that, It includes a drive box (1), a robotic arm (2) and several drive ropes (3); the drive box (1) is equipped with several drive units (12), and each drive unit (12) drives one of the drive ropes (3) to extend and retract; The robotic arm (2) includes a robotic arm extension rod (21), several spacer discs (22) and a load-end spacer disc (23), which are connected in series. The robotic arm (2) includes at least one motion segment, which is composed of several spacer discs (22) connected in series or several spacer discs (22) connected in series and a load-end spacer disc (23). At least one through hole is provided at each of the four corners of the robotic arm extension rod (21), several spacer discs (22) and load-end spacer disc (23). Every four ropes form a group, one end of which is fixed to the corresponding drive unit (12) and passes through the through holes at the four corners in sequence, and the other end is fixed to the end structure of the motion segment. One end of the extension rod (21) of the robotic arm is fixed to the drive box (1); two pin holes are arranged oppositely on the inner side wall of the other end; grooves are symmetrically arranged on the outer side wall of the other end; pin holes are symmetrically arranged on the four inner side walls of the spacer (22); two opposite outer side walls are equipped with shafts at one end for installing bearings; and grooves are provided at the other end of the other two opposite outer side walls; two pin holes are arranged oppositely on the inner side wall of the load end spacer (23); and shafts are provided oppositely on the outer side walls for installing bearings. For the series connection between two adjacent spacers (22), one end of each of the two flexible metal rods is inserted into the opposing pin hole of one of the spacers (22), and the other end is inserted into the opposing pin hole of the other spacer (22) to form a flexible connection; the lower part of the bearing seat is installed on the groove of one of the spacers (22), and the upper part of the bearing seat is provided with a limiting groove, which cooperates with the outer ring of the bearing installed on the other spacer (22) to form a rotary joint; the adjacent robotic arm extension rod (21) and spacer (22), and the adjacent spacer (22) and load end spacer (23) are connected in series in the same way.

2. The multi-degree-of-freedom rope-driven continuum robot according to claim 1, characterized in that, Each group of four ropes has one end fixed to the corresponding drive unit (12) and passes through the through holes at the four corners in sequence. The other end is fixed to the end structure of the action segment to achieve the following movement: By controlling the tension or relaxation of the two drive ropes (3) on the left and the relaxation or tension of the two drive ropes (3) on the right, the yaw motion of the robotic arm (2) can be achieved. By controlling the tension or relaxation of the two drive ropes (3) on the lower and the relaxation or tension of the two drive ropes (3) on the upper, the pitch motion of the robotic arm (2) can be achieved.

3. The multi-degree-of-freedom rope-driven continuum robot according to claim 1, characterized in that, The drive box (1) includes a spliced ​​frame (11), several drive units (12), several motor-side dual-purpose wiring boards (13), main-side wiring boards (14), and a robotic arm adapter plate (15). The spliced ​​frame (11) is divided into an inner frame (111) and an outer frame (112). The inner frame (111) is fixed inside the outer frame (112). Several drive units (12), several motor-side dual-purpose wiring boards (13), and main-side wiring boards (14) are fixed on the inner frame (111), and the robotic arm adapter plate (15) is fixed on the outer frame (112). Each drive unit (12) corresponds to one motor-side dual-purpose wiring board (13).

4. A multi-degree-of-freedom rope-driven continuum robot according to claim 1, characterized in that, Each group consists of four ropes, which correspond to four drive units (12). Two drive units (12) are installed on one side of the inner frame (111), and the other two drive units (12) are installed on the other side of the inner frame (111). The drive ropes (3) driven by the drive units (12) on the same side and adjacent to each other rotate in opposite directions.

5. A multi-degree-of-freedom rope-driven continuum robot according to any one of claims 1-4, characterized in that, The drive unit (12) includes a brushless motor backplate (121), a brushless motor (122), and a drive rope winch (123); the brushless motor backplate (121) is used to fix the brushless motor (122); the brushless motor (122) is fixed with the drive rope winch (123), and one end of the drive rope (3) is fixed on the drive rope winch (123) to drive the drive rope winch (123) to rotate, thereby realizing the loosening and tightening of the drive rope (3); Two notches are reserved on the radial outer side of the drive rope winch (123). Each drive unit (12) is equipped with a manual winding wrench (124). The protrusion inside the manual winding wrench (124) engages with the notch of the drive rope winch (123) to enable manual winding and manual adjustment.

6. A multi-degree-of-freedom rope-driven continuum robot according to claim 3, characterized in that, The dual-purpose wiring board (13) on the motor side includes a wiring board body (131), a first flexible tube quick connector (132), and a flexible tube (133); the first flexible tube quick connector (132) is fixed on the wiring board body (131); The main side wiring board (14) includes a wiring board body (141) and a number of second flexible hose quick connectors (142). The number of second flexible hose quick connectors (142) is the same as the number of motor side dual-purpose wiring boards (13). One end of the flexible hose (133) is inserted into the first flexible hose quick connector (132), and the other end is inserted into the second flexible hose quick connector (142) to form a channel for the drive rope (3). The robotic arm adapter plate (15) includes an adapter plate body (151) and four fastening screws (152). The four sides of the adapter plate body (151) each have a threaded through hole and a central hollow, which are used to install the robotic arm extension rod (21). The four fastening screws (152) are evenly and symmetrically distributed on the four sides of the adapter plate body (151). The coaxiality adjustment between the central axis of the robotic arm extension rod (21) and the central axis of the robotic arm adapter plate (15) is achieved by screwing in and out two opposing screws.

7. A multi-degree-of-freedom rope-driven continuum robot according to claim 1, characterized in that, The cross-section of the robotic arm (2) is rectangular, with a hollowed-out central area for the passage of sensor wire harnesses at the end of the robotic arm (2).

8. A multi-degree-of-freedom rope-driven continuum robot according to claim 1, characterized in that, The load-end spacer (23) includes a spacer body (231) and a detachable load device (233); the inner sidewall of the spacer body (231) has two opposing pin holes, and the outer sidewall is equipped with shafts for installing bearings; the central area of ​​the spacer body (231) is hollowed out for inserting the detachable load device (233).

9. A multi-degree-of-freedom rope-driven continuum robot according to claim 8, characterized in that, The spacer body (231) and the detachable load device (233) are installed using a Snap-Fit design. The spacer body (231) has two opposing side openings. The detachable load device (233) can be installed by pushing it in from the head of the spacer body (231). When disassembling, the detachable load device (233) can be removed by inserting a pin into the side opening of the spacer body (231).

10. A multi-degree-of-freedom rope-driven continuum robot according to claim 1, characterized in that, The end of the extension rod (21) of the robotic arm connected to the spacer (22) is an inclined plane, both ends of the spacer (22) are inclined planes, the end of the load-end spacer (23) connected to the spacer (22) is an inclined plane, all the inclined planes have the same inclination angle, and the adjacent two inclined planes form a symmetrical n° angle; the sum of the number of the spacer (22) and the load-end spacer (23) is 2×180 / n, so as to achieve a maximum pitch angle and a maximum yaw angle of 180° at the end of the robotic arm (2).

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