A small-volume and large-stroke passive tensioning device for a rope-driven manipulator

Abstract

The present invention discloses a small-volume and large-stroke passive tensioning device for a rope-driven robotic arm, comprising a driving motor, a supporting structure, a cable cover and an integrated winding structure; wherein the supporting structure is used to connect the driving motor and the cable cover, so that the cable cover, the supporting structure and the driving motor form a closed space to constrain and protect the integrated winding structure; the integrated winding structure comprises a fixed core shaft, a tensioning coil spring, a winding wheel and a driving rope wound on the winding wheel; the fixed core shaft is connected to the driving shaft of the driving motor, one end of the tensioning coil spring is connected to the fixed core shaft, and the other end is connected to the winding wheel; the winding wheel can rotate a certain number of circles relative to the fixed core shaft, and if the driving rope becomes loose during the process of contracting the driving rope, the driving rope will be tightened in time to realize the continuous pre-tightening function, thereby preventing the driving rope from becoming loose or knotted during the reciprocating extension and bending deformation control of the robotic arm, thereby improving the control accuracy of the rope-driven flexible robotic arm.

Description

Technical Field

[0001] The present invention relates to the field of aerospace, specifically to the field of flexible manipulator arms and rope drive technology for spacecraft, and in particular to a small-volume and large-stroke passive tensioning device for rope-driven manipulator arms. Background Art

[0002] Rope-driven flexible robotic arms are used in satellite payload equipment, such as solar cells, onboard antennas, space robots, etc.

[0003] During the reciprocating telescopic and bending deformation control process of the rope-driven flexible robotic arm, part of the driving rope will be loose or even knotted. When the operation is completed and the initial state is restored, the zero position will often be inaccurate due to the influence of the loose or knotted driving rope, which seriously affects the control accuracy of the flexible arm. The present invention proposes a mechanism for tensioning the driving rope, which realizes the long-stroke passive tensioning function of the driving rope of the rope-driven flexible telescopic robotic arm.

[0004] As a major category of flexible robotic arms, rope-driven flexible robotic arms have attracted widespread attention due to their fast response speed, relatively simple structure, and easy high-precision control. Rope-driven flexible robotic arms generally use a combination of ropes and passive joints, and transmit driving force through the ropes to achieve the telescopic and bending deformation of the passive joints. Due to the basic characteristics of the rope and the influence of the elastic deformation of the flexible arm itself, the driving rope will inevitably become loose during the operation process and after the operation is completed and reset, so the wound rope needs to be tensioned.

[0005] The tensioning methods are generally divided into two types: active tensioning and passive tensioning. The active tensioning method ("A sleeve-type extension and retraction mechanism rope-driven tensioning device and its control method—CN 107013641 A", "A tensioning mechanism applied to a rope-driven robot—CN 114589683 A") is mainly achieved by actively controlling the drive motor or tensioning motor to retract the drive rope when the rope is loose through the design of a complex program control compensation algorithm or through operator observation. The passive tensioning method "A spring-type automatic tensioning mechanism—CN 206988069 U", "A transmission rope pretensioning device for a rope-driven mechanical arm—CN109986545 A" is mainly achieved by setting a tensioning spring to achieve tension in a smaller range.

[0006] The programmable active tensioning method has the risk of low reliability due to the setting conditions of its compensation algorithm and the limitations of the algorithm itself, as well as its relatively complex structure. It is also unable to meet the cumulative error of the slack length of the drive rope, resulting in a gradual decrease in control accuracy. The operator-controlled active tensioning method cannot achieve higher automation requirements, and this method of having people in the loop will lead to greater errors.

[0007] The passive tensioning method of setting the tension spring can only achieve a small tension due to the limitation of the length of the tension spring. With the use of the flexible mechanical arm, the driving rope cannot be continuously relaxed. The driving rope still needs to be adjusted regularly. The operation is also very inconvenient due to the general use of screw tensioning and the limitation of installation space. Summary of the invention

[0008] In view of the problems existing in the prior art, the purpose of the present invention is to provide a small-volume and large-stroke passive tensioning device for a rope-driven robotic arm. The present invention is applied to the payload equipment of a spacecraft. Through the integrated design of the driving rope tensioning mechanism and the winding mechanism, the function of continuous passive tensioning of the driving rope can be achieved without adjusting the tensioning force.

[0009] To achieve the above-mentioned object, the present invention provides a small-volume and large-stroke passive tensioning device for a rope-driven manipulator, the device comprising a driving motor, a supporting structure, a cable harness housing and an integrated winding structure; wherein:

[0010] The support structure is used to connect the drive motor and the cable housing, so that the cable housing, the support structure and the drive motor form a closed space to constrain and protect the integrated winding structure;

[0011] The integrated winding structure includes a fixed core shaft, a tensioning spring, a winding wheel and a driving rope wound on the winding wheel; the fixed core shaft is connected to the driving shaft of the driving motor, one end of the tensioning spring is connected to the fixed core shaft, and the other end is connected to the winding wheel; the winding wheel can rotate a certain number of circles relative to the fixed core shaft. If the driving rope becomes loose during the process of contracting the driving rope, the driving rope will be tightened in time to achieve a continuous pre-tensioning function.

[0012] Furthermore, the tensioning spring is wrapped around the fixed core shaft, the inner circle hook at the innermost end of the tensioning spring is connected and fixed to the fixed core shaft, and the outer circle hook at the outermost end is connected to the winding wheel, so that the tensioning spring can continuously provide tensioning force for the device through tightening and relaxing in a limited space.

[0013] Furthermore, the fixed mandrel is fixedly connected to the driving shaft of the driving motor, and the fixed mandrel is driven to rotate when the driving shaft rotates; a fixed slot is provided on the fixed mandrel for connecting the inner ring hook of the tensioning coil spring.

[0014] Furthermore, the fixed core shaft 4 is a stepped shaft, a positioning hole is designed at one end, and a fixed slot connected to the tensioning coil spring is provided at the other end. A limit baffle is provided in the middle of the fixed core shaft, and a ball groove is provided on one side of the positioning hole.

[0015] Furthermore, the winding wheel is a cylindrical structure with a accommodating cavity, with wire blocking plates provided at both ends, and a fixing groove designed at one end for connecting the outer ring hook of the tensioning spring; the length of the fixing groove is greater than the width of the spring, and the accommodating cavity inside the winding wheel is used to place the tensioning spring and fix the core shaft.

[0016] Furthermore, the integrated winding structure also includes a baffle, which is used to constrain the tension coil spring so that the tension coil spring is retained in the accommodating cavity of the winding wheel.

[0017] Furthermore, a boss for constraining the tensioning coil spring is provided at one end of the baffle, and a plurality of connecting holes are axially provided for connecting the baffle and the winding wheel.

[0018] Furthermore, the supporting structure is an L-shaped connecting plate having a bottom plate and a vertical plate. The bottom plate of the supporting structure is rectangular, and mounting holes for connecting the drive motor are provided at the four corners. The vertical plate is a square plate, and a through hole is provided in the center of the vertical plate. Mounting holes for connecting the wiring harness cover are provided at the four corners of the vertical plate.

[0019] Furthermore, the cable cover is used to constrain the cable outlet direction of the drive rope; the cable cover has a bottom wall, four side walls and a mounting portion, the bottom wall is provided with a through hole, one end of the fixed core shaft can extend from the through hole; the four side walls are respectively provided with cable outlet holes; the mounting portion is provided with a mounting hole for connecting to the support structure.

[0020] Further, the assembly sequence of the device is as follows:

[0021] (1) First, insert the inner ring hook of the tension coil spring into the slot of the fixed core shaft and wind it tightly, then put the winding wheel on the outside of it, and insert the outer ring hook of the tension coil spring through the baffle designed on the winding wheel into the fixed slot. The winding wheel is designed with multiple slots to facilitate the adjustment of the installation position of the outer ring hook of the tension coil spring. Finally, connect the baffle and the winding wheel to ensure that the boss faces the direction of the tension coil spring, and complete the assembly of the integrated winding structure;

[0022] (2) Then, the integrated winding structure is connected to the drive shaft of the drive motor through a key or a screw in the direction of the positioning hole, so that there is no relative rotation between the fixed core shaft and the drive shaft. Then, the connected whole is passed through the middle through hole of the support structure. Finally, the part that passes through the middle through hole of the support structure is framed in the cable harness cover, and the cable harness cover is fixed to complete the assembly of the device.

[0023] The small-volume and large-stroke passive tensioning device for a rope-driven manipulator of the present invention is applied to on-orbit equipment in aerospace engineering, mainly to satellite payload equipment, such as solar cells, satellite-borne antennas, space robots, etc. on satellites.

[0024] The tensioning device proposed in the present invention has the characteristics of compact structure, passive pre-tensioning, and long tensioning formation; the compact structure is reduced to an integrated design of the tensioning mechanism integrated winding assembly, which is equivalent to 1 / 4 of the motor volume; the passive tensioning is reflected in the fact that no additional tensioning drive motor or other energy input is required; the long stroke is reflected in the fact that the tensioning length of the 8mm winding radius in the example of the present invention can reach 500mm. The device can realize the function of continuous passive tensioning of the driving rope without adjusting the tensioning force, preventing the driving rope from being loose or knotted during the reciprocating telescopic and bending deformation control process of the robot arm, thereby effectively improving the control accuracy of the rope-driven flexible robot arm. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The overall schematic diagram of the small-volume and large-stroke passive tensioning device for a rope-driven mechanical arm according to the present invention is shown;

[0026] Figure 2 It shows a schematic cross-sectional installation diagram of a small-volume and large-stroke passive tensioning device for a rope-driven mechanical arm according to the present invention;

[0027] Figure 3 A schematic diagram of the structure of the cable harness cover according to the present invention is shown;

[0028] Figure 4 A schematic diagram of the structure of the winding wheel according to the present invention is shown;

[0029] Figure 5 A schematic diagram of the fixed mandrel structure according to the present invention is shown;

[0030] Figure 6 A schematic diagram of the tension coil spring structure according to the present invention is shown;

[0031] Figure 7 A schematic diagram of the baffle structure according to the present invention is shown;

[0032] Figure 8 A cross-sectional view of an integrated winding structure according to the present invention is shown;

[0033] Fig. 9 A stereogram of the integrated winding structure according to the present invention is shown;

[0034] Fig.10 A schematic diagram of the connection structure of the cable harness housing, the support structure and the drive motor according to the present invention is shown;

[0035] Fig.11 A schematic diagram of the assembly structure of the device according to the present invention is shown;

[0036] Fig.12 A schematic diagram showing an initial pre-tightening state of the device according to the present invention is shown;

[0037] Fig.13 A schematic diagram showing a state in which the preload force of the device according to the present invention is completely released is shown;

[0038] Fig.14 A graph showing the relationship between the maximum contraction rope length and the coil spring length according to the present invention is shown;

[0039] Fig.15 A graph showing the relationship between the maximum retracted rope length and the outer diameter of the winding wheel according to the present invention is shown. DETAILED DESCRIPTION

[0040] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0042] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] The following combination Figure 1-Figure 15 The specific embodiments of the present invention are described in detail. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0044] The present invention can be used for a space-variable configuration platform and a rope drive system that can be repeatedly folded and deployed, wherein the platform includes a flexible folding sail, a plurality of folding arms for supporting the flexible folding sail, and a drive device for driving the folding arms to move; the platform can be used to realize the repeated folding and driving of antennas on spacecraft. During the reciprocating telescopic and bending deformation control process of the rope-driven flexible robotic arm, some driving ropes will become loose or even knotted. When the initial state is restored after the operation, the zero position will often be inaccurate due to the influence of the loose or knotted driving rope, which seriously affects the control accuracy of the flexible arm. The present invention proposes a mechanism for tensioning the driving rope, which realizes the long-stroke passive tensioning function of the driving rope of the rope-driven flexible telescopic robotic arm.

[0045] According to the present invention, a small-volume and large-stroke passive tensioning device for a rope-driven mechanical arm is Figure 1 As shown in the figure, the design integrates the drive rope winding mechanism, and its overall schematic diagram is as follows Figure 1 As shown, the small-volume and large-stroke passive tensioning device for the rope-driven manipulator comprises a driving motor 8, a supporting structure 7, a cable housing 1 and an integrated winding structure. The integrated winding structure comprises a baffle 6, a tensioning coil spring 5, a fixed mandrel 4, a winding wheel 2 and a driving rope 3 wound on the winding wheel 2. The tensioning device of the present invention has the characteristics of compact structure, passive tensioning of pre-tensioning force, and long tensioning formation; the integrated winding structure obtained by the integrated design of the tensioning mechanism integrated winding assembly makes the structure compact and small, which is only equivalent to 1 / 4 of the volume of the driving motor; the passive tensioning is reflected in the fact that no additional tensioning driving motor or other energy input is required; the long stroke is reflected in that the tensioning length of the 8mm winding radius in the example of the present invention can reach 500mm.

[0046] Figure 2 The schematic diagram of the installation structure of a small-volume and large-stroke passive tensioning device for a rope-driven manipulator is shown. The drive motor 8 is used to provide driving force for the passive tensioning device, and the drive shaft of the drive motor 8 is connected to the integrated winding structure to provide driving force for the flexible and retractable manipulator and preload force for the tensioning coil spring 5 of the integrated winding structure.

[0047] The support structure 7 is an L-shaped connecting plate with a bottom plate and a vertical plate, which is used to connect the drive motor 8 and the cable housing 1. The bottom plate of the support structure 7 is rectangular, and the four corners are provided with mounting holes for connecting the drive motor 8. The vertical plate of the support structure 7 is a square plate, and the center of the vertical plate is provided with a through hole for accommodating the baffle 6, and the four corners of the vertical plate are provided with mounting holes for connecting the cable housing 1. The cable housing 1 is used to constrain the direction of the drive rope 3, and the cable housing 1, the support structure 7, and the drive motor 8 form a closed space to constrain and protect the integrated winding structure.

[0048] The integrated winding structure includes a fixed mandrel 4, a tension coil spring 5, a winding wheel 2, a baffle 6 and a driving rope 3 wound on the winding wheel 2. The fixed mandrel 4 is used to connect the motor drive shaft and the inner circle hook 52 of the coil spring 5, so that the drive motor 8 can continuously provide tension and the driving force of the retractable flexible mechanical arm, wherein the fixed mandrel 4 is fixedly connected to the drive shaft of the drive motor 8, and the drive motor drives the fixed mandrel 4 to rotate when it is started; the fixed mandrel 4 is provided with a coil spring fixing slot 42 for connecting the inner circle hook 52 of the tension coil spring 5. The tension coil spring 5 is surrounded by multiple circles on the fixed mandrel 4, the innermost inner circle hook 52 is connected and fixed to the fixed mandrel 4, and the outer circle hook 51 is connected to the winding wheel 2. The tension coil spring 5 fixed by the inner circle hook 52 and the outer circle hook 51 continuously provides tension for the device through tightening and loosening in a limited space. The winding wheel 2 is provided with a receiving cavity 24 for receiving the tension coil spring 5, and the winding wheel 2 is provided with a fixing groove 23 for connecting the outer ring hook 52 of the tension coil spring 5. The baffle 6 is used to constrain the tension coil spring 5 so that the tension coil spring 5 remains in the receiving cavity 24 of the winding wheel 2. The winding wheel 2 is used to wind the driving rope 3, and the first baffle plate 21 and the second baffle plate 22 are designed at both ends of the winding wheel 2, and one end is provided with a fixing groove 23 for the tension coil spring 5, and the length of the fixing groove 23 is greater than the width of the tension coil spring 5. The driving rope 3 is used to drive the flexible and retractable mechanical arm.

[0049] Figure 3 The specific structure of the cable harness cover 1 is shown. The cable harness cover 1 is a square structure as a whole, with a bottom wall, four side walls and mounting parts located at four corners. A through hole is provided on the bottom wall, and one end of the fixed core shaft 4 can extend from the through hole; the four side walls are respectively provided with cable outlet holes 11, and the cable outlet holes 11 adopt a large rounded corner design to effectively reduce the friction of the rope; the mounting part is provided with a mounting hole for connecting with the support structure 7.

[0050] Figure 4 The specific structure of the winding wheel 2 is shown. The winding wheel 2 is a cylindrical structure with an accommodating cavity 24, and a first wire baffle plate 21 and a second wire baffle plate 22 are designed at both ends. A coil spring fixing groove 23 is designed at one end, and the length of the fixing groove 23 is greater than the width of the coil spring 5. The interior of the winding wheel 2 is designed with a through-hole type hollow design (accommodating cavity 24) for placing the coil spring 5 and fixing the core shaft 4.

[0051] Figure 5 The specific structure of the fixed core shaft 4 is shown. The fixed core shaft 4 is a stepped shaft with a positioning hole 41 designed at one end and a fixed slot 42 connected to the tensioning spring 5 at the other end. A limit baffle 43 is provided in the middle of the fixed core shaft 4, and a ball groove 44 is designed on one side of the positioning hole 41. The ball groove 44 is used to install balls to reduce the friction between the fixed core shaft 4 and the winding wheel 2 during relative rotation.

[0052] Figure 6The specific structure of the tension coil spring 5 is shown. The tension coil spring 5 is a multi-layer ring structure formed by curling a metal sheet. Both ends are provided with hooks for connecting the winding wheel 2 and the fixed core shaft 4, which correspond to the outer circle hook 51 and the inner circle hook 52 respectively.

[0053] Figure 7 The specific structure of the baffle 6 is shown. The baffle 6 is an annular structure, one end of which is provided with a boss 61 for constraining the tensioning coil spring 5, and a plurality of connecting holes 62 are axially provided. The connecting holes 62 are used to realize the bolt connection between the baffle 6 and the threaded holes on the first wire baffle 21 of the winding wheel 2.

[0054] like Figure 8 and 9 As shown, the assembly sequence of the small-volume and large-stroke passive tensioning device for the rope-driven manipulator is as follows:

[0055] (1) First, insert the inner ring hook 52 of the tension coil spring 5 into the slot 42 of the fixed core shaft 4 and wind it tightly, then put the winding wheel 2 on the outside of it, and insert the outer ring hook 51 of the tension coil spring 5 through the first wire baffle plate 21 designed on the winding wheel 2 into the fixed slot 23. The winding wheel 2 is designed with multiple slots to facilitate the adjustment of the installation position of the outer ring hook of the tension coil spring 5. Finally, connect the baffle plate 6 and the winding wheel 2 to ensure that the boss 61 is facing the direction of the tension coil spring 5, and complete the assembly of the integrated winding structure;

[0056] (2) Then, the integrated winding structure is connected to the drive shaft of the drive motor 8 through a key or a screw in the direction of the positioning hole 41, so that the fixed core shaft 4 and the drive shaft will not rotate relative to each other. Then, the connected whole is passed through the middle through hole of the support structure 7, and finally, the part passing through the middle through hole of the support structure 7 is framed in the cable harness cover 1, as shown in FIG. Fig.10 , Fig.11 As shown, the cable harness cover 1 is fixed to complete the assembly of the device.

[0057] The working process and principle of the small volume and large stroke passive tensioning device for rope-driven manipulators are as follows:

[0058] Since the initial state is the pre-tightened state, when the drive motor 8 needs to be controlled to retract the drive rope 3, the drive rope 3 will be wound around the outer ring of the winding wheel 2. Since the winding wheel 2 sealed in the reserved space between the cable cover 1 and the support structure 7 can rotate a certain number of turns relative to the fixed core shaft 4 (which can be designed according to the required maximum single pre-tightening length), if the drive rope 3 becomes loose during the process of retracting the drive rope 3, the tensioning device will tighten the drive rope 3 in time; considering that the tensioning coil spring 5 may release part of the pre-tightening force before the drive motor 8 retracts the drive rope 3, but since the maximum tensioning force is equivalent to the driving force required for zero position maintenance, when the drive rope 3 is retracted at this time, the tensioning force of the tensioning coil spring 5 will first reach the maximum, and then the drive rope 3 will be wound around the winding wheel 2, thereby realizing the continuous pre-tightening function of the device of the present invention.

[0059] If the driving rope 3 needs to be released, the driving motor 8 only needs to be controlled in reverse, and the driving rope 3 can be released on the winding wheel 2.

[0060] The method for calculating the single maximum contraction length of the device of the present invention is as follows:

[0061] In the initial pre-tensioned state, the tension coil spring 5 is tightly wound around the fixed core shaft 4. Fig.12 As shown, the number of the first winding turns is , fix the radius of the mandrel , tension coil spring thickness and length The relationship between them is:

[0062]

[0063] in: The remaining part that has not been wound; .

[0064] According to formula (1), the first winding number is expression:

[0065]

[0066] in:

[0067]

[0068] After the preload is fully released, the tension spring is tightly attached to the inner wall of the winding wheel. Fig.13 As shown, the second winding number is , Inner radius of winding wheel , tension coil spring thickness and length The relationship between them is:

[0069]

[0070] in: The remaining part that has not been wound; .

[0071] According to formula (3), the second winding number is expression:

[0072]

[0073] in:

[0074]

[0075] Due to the length of the tensioned coil spring remain unchanged, , The radius difference brings the first winding number and the second winding number This difference directly affects the maximum rope length that can be retracted at a time.

[0076] Assume that the maximum retractable rope length is , the outer radius of the winding wheel is ( ), then:

[0077]

[0078] Combining formula (2)(4)(5):

[0079]

[0080] in: ; ;

[0081] Extended to any single contraction length , then:

[0082]

[0083] in, Reel rotation angle for single retraction:

[0084]

[0085] in, The length of the coiled spring that affects a single contraction.

[0086] From the above derivation, it is easy to know that the maximum stroke With fixed mandrel radius , Inner radius of winding wheel , the outer radius of the winding wheel is , Spring thickness And coil spring length The relationship between the spring thickness and At the same time, it will affect the preload force of the coil spring. Generally, the thickness is not used as a design variable for the preload length.

[0087] The following are two ways to increase the maximum travel Design method:

[0088] Method 1: Fixed, taking into account the inner diameter of the winding wheel The outer diameter and the coil spring preload and fixed mandrel radius The design range is small due to the size of the motor drive shaft, so when determining the outer radius of the winding wheel, In this case, the maximum stroke can be increased by appropriately increasing the length of the coil spring. ;

[0089] Method 2: Coil Spring Length Fixed due to fixed mandrel radius Affected by the size of the motor drive shaft, the design range is small, and the inner diameter of the winding wheel is The outer diameter and the coil spring preload. If you want to increase the maximum stroke while keeping the same , just increase the outer radius of the winding wheel to It can be achieved.

[0090] Example: , , , Take 15;

[0091] According to formula (6), we have:

[0092]

[0093] Pick , then and Relationship Fig.14 . along with Increase and increase, with The square of is positively correlated.

[0094] Pick , then and Relationship Fig.15 . along with Increase and increase, with There is a positive correlation.

[0095] Technical advantages:

[0096] Based on the small-volume and large-stroke passive tensioning device and operating principle for the rope-driven robotic arm provided by the present invention, through the integrated design of the driving rope tensioning mechanism and the winding mechanism, the function of continuous passive tensioning of the driving rope can be achieved without adjusting the tensioning force, thereby preventing the driving rope from becoming loose or knotted during the reciprocating extension and bending deformation control of the robotic arm, thereby effectively improving the control accuracy of the rope-driven flexible robotic arm.

[0097] Any process or method description in the flowchart of the present invention or described in other ways herein can be understood as a module, segment or part of a code including one or more executable instructions for implementing the steps of a specific logical function or process, which can be implemented in any computer-readable medium for use by an instruction execution system, device or equipment, and the computer-readable medium can be any medium containing storage, communication, propagation or transmission programs for use by execution systems, devices or equipment, including read-only memories, magnetic disks or optical disks, etc.

[0098] In the description of this specification, the description with reference to the terms "embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. In addition, those skilled in the art can combine or combine different embodiments or examples described in this specification and the features therein without causing any contradiction.

[0099] Although the above content has shown and described the embodiments of the present invention, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace, modify and other update operations on the above embodiments within the scope of the present invention.

Claims

1. A small-volume and large-stroke passive tensioning device for a rope-driven manipulator, characterized in that: The device comprises a driving motor, a supporting structure, a cable housing and an integrated winding structure; wherein, The support structure is used to connect the drive motor and the cable housing, so that the cable housing, the support structure and the drive motor form a closed space to constrain and protect the integrated winding structure; The integrated winding structure comprises a fixed mandrel, a tension coil spring, a winding wheel and a driving rope wound on the winding wheel; the fixed mandrel is connected to the driving shaft of the driving motor, one end of the tension coil spring is connected to the fixed mandrel, and the other end is connected to the winding wheel; so that the winding wheel rotates a certain number of times relative to the fixed mandrel; Since the initial state is a pre-tightened state, when the drive motor needs to be controlled to retract the drive rope, the drive rope will be wound around the outer ring of the winding wheel; the winding wheel sealed in the reserved space between the cable cover and the support structure can rotate a set number of circles relative to the fixed core shaft. If the drive rope becomes loose during the process of retracting the drive rope, the tensioning device will tighten the drive rope in time; when retracting the drive rope, the tensioning force of the tensioning coil spring will first reach the maximum, and then the drive rope will be wound around the winding wheel, so as to realize the continuous pre-tightening function; If you need to release the driving rope, just reverse the control of the driving motor and the driving rope will be released on the winding wheel; The calculation method of the maximum contraction length at a time is as follows: In the initial pre-tightened state, the tension coil spring is tightly wound around the fixed mandrel. At this time, the first winding number is , fix the radius of the mandrel , tension coil spring thickness and length The relationship between them is: （1） in, The remaining part of the tension coil spring that has not been wound in the initial pre-tensioned state; According to formula (1), the first winding number is expression: （2） Among them, the length of the tension coil spring is required to meet the following requirements: After the preload is fully released, the tension spring is tightly attached to the inner wall of the winding wheel. , Inner radius of winding wheel , tension coil spring thickness and length The relationship between them is: （3） in, It is the remaining part of the tension coil spring that has not been wound after the preload force is completely released; According to formula (3), the second winding number is expression: （4） Among them, the length of the tension coil spring is required to meet the following requirements: Due to the length of the tensioned coil spring remain unchanged, , The radius difference brings the first winding number and the second winding number This difference directly affects the maximum rope length that can be retracted at a time; Assume that the maximum retractable rope length is , the outer radius of the winding wheel is , then: （5） Combining formula (2)(4)(5): （6） in, ; ; ; Extended to any single contraction length , then: （7） in, Reel rotation angle for single retraction: （8） in, To affect the length of the coil spring for a single contraction; It is the remaining part that is not wound before the single contraction of the winding wheel rotation angle; It is the remaining part that is not wound after the single contraction of the winding wheel rotation angle; This gives: Maximum stroke With fixed mandrel radius , Inner radius of winding wheel , the outer radius of the winding wheel is , Spring thickness And coil spring length The relationship between.

2. The small-volume and large-stroke passive tensioning device for a rope-driven manipulator according to claim 1, characterized in that: The tensioning coil spring is wrapped around the fixed core shaft, the inner circle hook at the innermost end of the tensioning coil spring is connected and fixed to the fixed core shaft, and the outer circle hook at the outermost end is connected to the winding wheel, so that the tensioning coil spring can continuously provide tensioning force for the device through tightening and relaxing in a limited space.

3. The small-volume and large-stroke passive tensioning device for a rope-driven manipulator according to claim 2, characterized in that: The fixed mandrel is fixedly connected to the driving shaft of the driving motor, and the fixed mandrel is driven to rotate when the driving shaft rotates; a fixed slot is provided on the fixed mandrel for connecting the inner circle hook of the tensioning coil spring.

4. The small-volume and large-stroke passive tensioning device for a rope-driven manipulator according to claim 3, characterized in that: The fixed core shaft is a stepped shaft with a positioning hole designed at one end and a fixed slot connected to a tensioning coil spring at the other end. A limit baffle is provided in the middle of the fixed core shaft and a ball groove is provided on one side of the positioning hole.

5. The small-volume and large-stroke passive tensioning device for a rope-driven manipulator according to claim 4, characterized in that: The winding wheel is a cylindrical structure with a accommodating cavity, with wire blocking plates at both ends. A fixed groove is designed at one end for connecting the outer ring hook of the tensioning spring; the length of the fixed groove is greater than the width of the spring, and the accommodating cavity inside the winding wheel is used to place the tensioning spring and fix the core shaft.

6. The small-volume and large-stroke passive tensioning device for a rope-driven manipulator according to claim 5, characterized in that: The integrated winding structure also includes a baffle, which is used to constrain the tension coil spring so that the tension coil spring is retained in the accommodating cavity of the winding wheel.

7. The small-volume and large-stroke passive tensioning device for a rope-driven manipulator according to claim 6, characterized in that: One end of the baffle is provided with a boss for constraining the tension coil spring, and a plurality of connecting holes are axially provided for connecting the baffle and the winding wheel.

8. The small-volume and large-stroke passive tensioning device for a rope-driven manipulator according to claim 1, characterized in that: The support structure is an L-shaped connecting plate having a bottom plate and a vertical plate. The bottom plate of the support structure is rectangular, and mounting holes for connecting the drive motor are provided at the four corners. The vertical plate is a square plate, and a through hole is provided in the center of the vertical plate. Mounting holes for connecting the wiring harness cover are provided at the four corners of the vertical plate.

9. The small-volume and large-stroke passive tensioning device for a rope-driven manipulator according to claim 1, characterized in that: The cable cover is used to constrain the cable outlet direction of the drive rope; the cable cover has a bottom wall, four side walls and a mounting portion, the bottom wall is provided with a through hole, one end of the fixed core shaft extends out of the through hole; the four side walls are respectively provided with cable outlet holes; the mounting portion is provided with a mounting hole for connecting to the support structure.

10. The small-volume and large-stroke passive tensioning device for a rope-driven manipulator according to any one of claims 1 to 9, characterized in that: The assembly sequence of the device is as follows: (1) First, insert the inner ring hook of the tension coil spring into the slot of the fixed core shaft and wind it tightly, then put the winding wheel on the outside of it, and insert the outer ring hook of the tension coil spring through the baffle designed on the winding wheel into the fixed slot. The winding wheel is designed with multiple slots to facilitate the adjustment of the installation position of the outer ring hook of the tension coil spring. Finally, connect the baffle and the winding wheel to ensure that the boss faces the direction of the tension coil spring, and complete the assembly of the integrated winding structure; (2) Then, the integrated winding structure is connected to the drive shaft of the drive motor through a key or a screw in the direction of the positioning hole, so that there is no relative rotation between the fixed core shaft and the drive shaft. Then, the connected whole is passed through the middle through hole of the support structure. Finally, the part that passes through the middle through hole of the support structure is framed in the cable harness cover, and the cable harness cover is fixed to complete the assembly of the device.

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