A large-scale, lightweight, tension-driven space manipulator

Abstract

A large-scale, lightweight tension-driven space manipulator belongs to the field of space manipulators. While increasing the size of the space manipulator, the present invention ensures that the mass of the manipulator does not produce a nonlinear and substantial increase, thereby achieving the purpose of lightweighting the manipulator. The present invention includes a plurality of segmented arms, a plurality of connecting joints, a plurality of rope-driven mechanisms, and a plurality of lateral support mechanisms; a plurality of segmented arms are connected in series to form a manipulator, and each two adjacent segmented arms are hingedly connected by a connecting joint, and each two adjacent segmented arms are driven by a rope-driven mechanism to achieve bending at the joint; each connecting joint is slidably connected to a lateral support mechanism, and the two adjacent segmented arms are respectively located on both sides of the lateral support mechanism; the two adjacent segmented arms, a connecting joint, a rope-driven mechanism, and a lateral support mechanism constitute a joint drive module. The present invention is mainly used for grasping non-cooperative targets in space.

Description

Technical Field

[0001] The present invention relates to a space robot arm, and in particular to a large-scale, lightweight, tension-driven space robot arm. Background Art

[0002] Space robots are now the main objects of space missions. At present, space robot technology has achieved many research results, but there are still the following problems:

[0003] First, when facing large space non-cooperative targets (such as asteroids), it is necessary to increase the arm span of the space manipulator at the same time to increase the torque of the mechanical claw; for traditional manipulators, such as the "multi-section folding remote-controlled manipulator arm" disclosed in the Chinese patent "CN104070535B", the motor that drives the joint rotation is directly installed at the joint. Increasing the size of the manipulator will lead to an increase in the torque demand of the joint motor, which in turn leads to a nonlinear and substantial increase in the mass of the joint motor, making it difficult to control the mass of the entire manipulator within an ideal range and unable to achieve the purpose of lightweighting. Therefore, in order to adapt to the grasping of large space non-cooperative targets, while increasing the size of the space manipulator, how to ensure that the mass of the manipulator does not produce a nonlinear and substantial increase, and achieve the purpose of lightweighting the manipulator, is a problem that currently needs to be solved for large-scale space manipulators.

[0004] Second, as the size of the space robot arm increases, the volume of the outer packaging will also increase, which will not be able to adapt to the narrow cargo space of the launch vehicle. Summary of the invention

[0005] The technical problem to be solved by the present invention is: how to ensure that the mass of the robot arm does not produce a non-linear and substantial increase while increasing the size of the space robot arm in order to adapt to the grasping of large-scale non-cooperative targets in space, so as to achieve the purpose of lightweighting the robot arm. This is a problem that urgently needs to be solved for large-scale space robot arms. The present application further provides a large-scale lightweight tension-driven space robot arm, which reduces the torque at the joints by changing the structure and driving mode of the connecting joints, thereby reducing the output torque of the motor, and the mass of the motor does not produce a non-linear increase, thereby achieving the purpose of lightweighting the robot arm.

[0006] The technical solution adopted by the present invention to solve the above technical problems is:

[0007] A large-scale lightweight tension-driven space manipulator, comprising a plurality of segmented arms, a plurality of connecting joints, a plurality of rope-driven mechanisms and a plurality of transverse supporting mechanisms; the plurality of segmented arms are connected in series to form a manipulator, each two adjacent segmented arms are hingedly connected via a connecting joint, and each two adjacent segmented arms are driven by a rope-driven mechanism to achieve bending at the joint; each connecting joint is slidably connected to a transverse supporting mechanism, and the two adjacent segmented arms are respectively located on both sides of the transverse supporting mechanism; the two adjacent segmented arms, a connecting joint, a rope-driven mechanism and a transverse supporting mechanism constitute a joint driving module;

[0008] The rope drive mechanism includes a driving motor, a reducer, a winch, a guide wheel, a flexible driving rope and two groups of flexible driving rope tensioning assemblies. The driving motor, the reducer, the winch and one group of flexible driving rope tensioning assemblies are installed on one of the segmented arms and arranged at an end away from the connecting joint. The output end of the driving motor is connected to the input end of the reducer, and the output end of the reducer is fixedly connected to the winch. The guide wheel and another group of flexible driving rope tensioning assemblies are installed on the other segmented arm and arranged at an end away from the connecting joint. The flexible driving rope is annular. After the flexible driving rope passes around one of the groups of flexible driving rope tensioning assemblies, the two ends of the flexible driving rope pass around the winch in the reverse direction and pass through the two ends of the transverse support mechanism respectively. Finally, the two ends of the flexible driving rope pass around the guide wheel in the reverse direction and are sleeved on the other group of flexible driving rope tensioning assemblies. The flexible driving rope forms a quadrilateral structure under the support of the transverse support mechanism, and is always in a tensioned state under the action of the two groups of flexible driving rope tensioning assemblies.

[0009] Furthermore, the flexible driving rope is a cable; the winch is a differential winch, which is composed of two winches with different outer diameters that are coaxially fixedly connected.

[0010] Furthermore, each set of flexible drive rope tensioning assemblies includes a first pulley and a spring, one end of the spring is fixedly connected to the section arm, and the other end of the spring is connected to the first pulley via a pulley bracket.

[0011] Furthermore, the connecting joint includes a middle hinge plate, two sandwich hinge plates and two outer hinge plates. The two sandwich hinge plates and the two outer hinge plates are symmetrically arranged on both sides of the middle hinge plate. The outer hinge plate and the sandwich hinge plate on the same side are hingedly connected. The two sandwich hinge plates are hinged to the middle hinge plate through the same pin shaft. The two outer hinge plates are fixedly connected to two adjacent segment arms respectively, and the middle hinge plate is slidably connected to the lateral support mechanism.

[0012] Furthermore, a clamping block and a clamping slot are provided between the outer hinge plate and the sandwich hinge plate, and the two are fixedly connected by the cooperation of the clamping block and the clamping slot.

[0013] Furthermore, the middle hinge plate is an I-shaped structure, and a slide groove is respectively provided at the bottom and the top of the middle hinge plate.

[0014] Furthermore, the lateral support mechanism includes a transverse brace and a sliding traction assembly, and the sliding traction assembly is simultaneously installed on the middle hinge plate and the transverse brace. The transverse brace is a rectangular frame, and the upper and lower ends of the transverse brace are respectively provided with sliding rails along its length direction. The middle hinge plate and the transverse brace cooperate with the sliding groove and the sliding rail and, under the traction force of the sliding traction assembly, the transverse brace and the connecting joint can achieve linear movement and fixation along their own length direction.

[0015] Furthermore, when the robotic arm is working, the connecting joint is located at the middle position of the cross brace.

[0016] Furthermore, second pulleys are provided at both ends of the cross brace for supporting and guiding the flexible driving rope in the rope drive mechanism.

[0017] Furthermore, the sliding traction assembly includes two motors, two worm gear reducers, two third winches and two ropes; the two motors, worm gear reducers and third winches are respectively installed on the upper and lower end surfaces of the middle hinge plate, the output end of the motor is connected to the input end of the worm gear reducer, the output end of the worm gear reducer is fixedly connected to the third winch, one end of the rope is wound around the third winch, and the other end of the rope is fixed to the end of the cross brace and tensioned; the cross brace is moved by taking in and releasing the two ropes.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. In order to achieve the purpose of lightweighting the robotic arm, in addition to adopting a frame structure for each arm segment, connecting joint and cross brace to reduce its own mass, the driving mode of the robotic arm is also changed. That is, the combination of flexible drive rope drive and differential winch and the design of the cross brace greatly reduce the torque demand of the space robotic arm drive motor, so that the mass of the motor will not produce a nonlinear and substantial increase, and the mass increase rate is greatly reduced while the length of the robotic arm is increased, which provides a feasible solution for the design of super-large space robotic arms.

[0020] 2. The present application can realize 360° circumferential rotation between two adjacent segment arms in each joint drive module through the design of connecting joints, so that the entire robotic arm can be folded into a row in a Z shape, reducing the volume of the robotic arm when it is in a gathered state; at the same time, the joints that can rotate circumferentially also increase the working space of the robotic arm.

[0021] 3. The robot arm of the present application has a higher stiffness under the tension of the flexible drive rope, which reduces the stiffness requirement of the robot arm. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are incorporated as part of this application and are used to provide a further understanding of the present invention.

[0023] Figure 1 It is a structural schematic diagram of the mechanical arm of the present invention in a folded state;

[0024] Figure 2 It is a structural schematic diagram of the mechanical arm of the present invention in a straightened state;

[0025] Figure 3 It is a structural schematic diagram of the mechanical arm of the present invention in a bent state;

[0026] Figure 4 It is a structural diagram of the joint drive module;

[0027] Figure 5 for Figure 4 A partial enlarged view of the middle A;

[0028] Figure 6 for Figure 4 A partial enlarged view of point B in the middle;

[0029] Figure 7 It is a schematic diagram of the arrangement of the rope drive mechanism in the joint drive module;

[0030] Figure 8 It is a structural diagram of the connecting joint;

[0031] Fig. 9 It is a schematic diagram of the state of the connection joint when the angle between two adjacent segment arms is 0 degrees;

[0032] Fig.10 It is a schematic diagram of the state of the connection joint when the angle between two adjacent segment arms is 180 degrees;

[0033] Fig.11 It is a schematic diagram of the state of the connection joint when the angle between two adjacent segment arms is greater than 180 degrees and less than 360 degrees;

[0034] Fig.12 Schematic diagram of the structure connecting the joint, cross brace and section arm Figure 1 ;

[0035] Fig.13 Schematic diagram of the structure connecting the joint, cross brace and section arm Figure 2 ;

[0036] Fig.14It is a structural schematic diagram of the joint drive module when the connecting joint is in the middle position of the cross brace;

[0037] Fig.15 It is a structural schematic diagram of the joint drive module when the connecting joint is at the end position of the cross brace;

[0038] Fig.16 is a structural schematic diagram of the lateral support mechanism;

[0039] Fig.17 Schematic diagram of force analysis of differential winch.

[0040] Explanation of the reference numerals: 1-arm; 2-connecting joint; 2-1-middle hinge plate; 2-1-1-slide groove; 2-2-sandwich hinge plate; 2-3-outer hinge plate; 2-4-first pin; 2-5-second pin; 2-6-block; 2-7-slot; 3-rope drive mechanism; 3-1-drive motor; 3-2-reducer; 3-3-winch; 3-4-guide wheel; 3-5-first pulley; 3-6-spring; 3-7-flexible drive rope; 4-lateral support mechanism; 4-1-cross brace; 4-1-1-slide rail; 4-1-2-second pulley; 4-2-motor; 4-3-worm gear reducer; 4-4-third winch; 4-6-rope. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0042] See also Figure 1 The embodiment of the present application provides a large-scale lightweight tension-driven space manipulator, which includes a plurality of segmented arms 1, a plurality of connecting joints 2, a plurality of rope-driven mechanisms 3 and a plurality of lateral support mechanisms 4; the plurality of segmented arms 1 are connected in series to form an integral manipulator, and each two adjacent segmented arms 1 are hingedly connected by a connecting joint 2, and each two adjacent segmented arms 1 are driven by a rope-driven mechanism 3 to achieve bending at the joint; each connecting joint 2 is slidably connected to a lateral support mechanism 4, and the two adjacent segmented arms 1 are respectively located on both sides of the lateral support mechanism 4, and the lateral support mechanism 4 provides support force for the rope-driven mechanism 3 to ensure stable driving force of the rope-driven mechanism 3, and at the same time, the setting of the lateral support mechanism 4 can also reduce the torque at the connecting joint 2; the two adjacent segmented arms 1, a connecting joint 2, a rope-driven mechanism 3 and a lateral support mechanism 4 constitute a complete joint drive module.

[0043] See also Figure 1In order to achieve the purpose of lightweighting the robot arm while ensuring the rigidity of each segment arm 1, each segment arm 1 is a rectangular hollow arm body, and the outer wall of each segment arm 1 is hollow.

[0044] See also Figure 8 The connecting joint 2 is used to realize 360° circumferential rotation between two adjacent segment arms 1 in each joint driving module; the connecting joint 2 is formed by five symmetrically arranged hinge plates which are hinged in sequence, and the whole forms a folding plate structure bent toward the middle; the five hinge plates are respectively a middle hinge plate 2-1, two sandwich hinge plates 2-2 and two outer hinge plates 2-3, the two sandwich hinge plates 2-2 and the two outer hinge plates 2-3 are respectively arranged on both sides of the middle hinge plate 2-1, and the outer hinge plate 2-3 on the same side is hinged to the sandwich hinge plate 2-2 and one of the outer hinge plates 2-3 The side end faces are hinged to one of the side end faces of the sandwich hinge plate 2-2 through the first pin shaft 2-4, and the rotation of the two outer hinge plates 2-3 realizes that the angle between the two adjacent segment arms 1 is from 0° to 180°. The other side end faces of the two sandwich hinge plates 2-2 are hinged to the same end of the middle hinge plate 2-1 through the second pin shaft 2-5, so that the angle between the two adjacent segment arms 1 is from 180° to 360°. The two outer hinge plates 2-3 are fixedly connected to the two adjacent segment arms 1 respectively, and the middle hinge plate 2-1 is slidably connected to the lateral support mechanism 4.

[0045] Furthermore, the five hinge plates are all frame-type plates to reduce the weight of the joints of the robot arm and achieve the purpose of lightweight.

[0046] Furthermore, the middle hinge plate 2-1 is an I-shaped structure, and a slide groove 2-1-1 is respectively provided at the bottom and the top of the middle hinge plate 2-1.

[0047] Furthermore, a clamping block 2-6 and a clamping slot 2-7 are provided between the outer hinge plate 2-3 and the sandwich hinge plate 2-2, and the two are fixedly connected by the cooperation of the clamping block 2-6 and the clamping slot 2-7, thereby ensuring the symmetry and stability of the bending of the two segment arms 1.

[0048] Furthermore, the card block 2-6 is installed on the interlayer hinge plate 2-2 and is located on the side opposite to the outer hinge plate 2-3, and the card slot 2-7 is arranged on the outer hinge plate 2-3.

[0049] The robot arm of the present application is driven by several rope drive mechanisms 3, and finally realizes the change of the length of the robot arm and the determination of the position of the end robot claw by changing the angle between two adjacent segment arms 1 by each connecting joint 2; in each joint driving module, the angle between two adjacent segment arms 1 can be rotated from 0° to 360° under the action of the connecting joint. The specific rotation process is as follows: the state of the five hinge plates in the connecting joint is as follows: Fig. 9 As shown, two adjacent segmented arms 1 are arranged side by side and close to each other, and the angle between them is 0°. The rope drive mechanism 3 in each joint driving module pulls the two adjacent segmented arms 1 with equal force, and the two segmented arms 1 respectively drive the outer hinge plates 2-3 to rotate with their respective first pin shafts 2-4 as the central axis, and the angle between the outer hinge plates 2-3 and the sandwich hinge plates 2-2 gradually decreases. During this process, the two sandwich hinge plates 2-2 and the middle hinge plates 2-1 are always fitted together and keep their positions stationary, until the two outer hinge plates 2-3 and the sandwich hinge plates 2-2 connected thereto respectively have an angle of 0° and fit tightly together, and the outer hinge plates 2-3 and the sandwich hinge plates 2-2 are fixed by the cooperation of the clamping blocks 2-6 and the clamping slots 2-7, and at this time the angle between the two segmented arms 1 changes from 0° to 180°; at this time, the state changes of the five hinge plates in the connecting joint are as follows Fig.10 As shown, the rope drive mechanism 3 continues to pull the two segmented arms 1 with the same force, and the two segmented arms 1 respectively drive the two sandwich hinge plates 2-2 to rotate around the second pin shaft 2-5 as the central axis through the outer hinge plate 2-3, and the angle between the two sandwich hinge plates 2-2 and the middle hinge plate 2-1 gradually increases as shown in FIG. Fig.11 As shown, until the two segmented arms 1 are brought together again, the angle between them changes from 180° to 360°; during the entire connection joint movement process, the two outer hinge plates 2-3 perform a circumferential rotation from -180° to 180°, and the two segmented arms 1 perform symmetrical rotational movement with the middle hinge plate 2-1 as the center dividing plane, achieving a large angle change.

[0050] See also Figure 5 , Figure 6 and Figure 7The rope drive mechanism 3 includes a driving motor 3-1, a reducer 3-2, a winch 3-3, a guide wheel 3-4, a flexible driving rope 3-7 and two sets of flexible driving rope tensioning components. The driving motor 3-1, the reducer 3-2, the winch 3-3 and one set of flexible driving rope tensioning components are installed on one of the segmented arms 1 and are arranged at the end away from the connecting joint 2. The output end of the driving motor 3-1 is connected to the input end of the reducer 3-2, and the output end of the reducer 3-2 is fixedly connected to the winch 3-3. The driving motor 3-1 realizes the low-speed rotation of the winch 3-3 through the deceleration of the reducer 3-2. The guide wheel 3-4 and another set of flexible driving rope tensioning components are installed on the other segmented arm 1 and are arranged At one end away from the connecting joint 2; the flexible driving rope 3-7 is ring-shaped. After the flexible driving rope 3-7 passes around one of the groups of flexible driving rope tensioning components, the two ends of the flexible driving rope 3-7 pass around the winch 3-3 in the reverse direction and pass through the two ends of the lateral support mechanism 4 respectively. Finally, the two ends of the flexible driving rope 3-7 pass around the guide wheel 3-4 in the reverse direction and are put on the other group of flexible driving rope tensioning components. The winch 3-3 has a driving effect on the flexible driving rope 3-7, and the rotation of the robot arm is realized by changing the tension of the cables entering and exiting on both sides of the winch; the flexible driving rope 3-7 forms a quadrilateral structure under the support of the lateral support mechanism 4, and is always in a tensioned state under the action of the two groups of flexible driving rope tensioning components.

[0051] Furthermore, the reducer 3-2 is composed of a combination of a harmonic reducer and a worm gear reducer.

[0052] Furthermore, the flexible drive rope 3-7 is preferably a cable, and the winch 3-3 is a differential winch, which is composed of two winches with different outer diameters that are coaxially fixedly connected, and the tension is changed by the friction force of the winch on the flexible drive rope; the purpose of setting a differential winch in the present application is to reduce the torque of the drive motor 3-1, thereby reducing the mass of the drive motor 3-1.

[0053] Furthermore, each set of flexible drive rope tensioning assemblies includes a first pulley 3-5 and a spring 3-6, one end of the spring 3-6 is fixedly connected to the section arm 1, and the other end of the spring 3-6 is connected to the first pulley 3-5 through a pulley bracket.

[0054] The design of the rope-driven mechanism 3 of the present application reduces the demand for the stiffness of the robot arm. When the robot arm is subjected to external force, if there is no cable, the robot arm will produce corresponding deformation under the action of the external force; and when there are cables at both ends, when subjected to external force, first the tension in the cable will change to a certain extent, thereby reducing the effect of the external force directly acting on the robot arm, so the deformation will be reduced, which is equivalent to increasing the stiffness of the robot arm.

[0055] The rope drive mechanism 3 of the present application adopts a combination of flexible drive rope drive and differential winch to greatly reduce the torque requirement of the space robot drive motor, so that the mass of the motor will not produce a nonlinear and substantial increase, further achieving the purpose of lightweighting the space robot.

[0056] Specifically, since the drive motor 3 - 1 and the joint of the robot arm are remotely arranged, the length of the force arm is increased, and the output torque of the drive motor 3 - 1 is reduced while the torque at the joint of the robot arm remains unchanged.

[0057] Also, see Fig.17 , for the differential winch, let Where L is the total length of the cross brace, α is the angle between the section arm and the flexible drive rope, assuming that the tension of the flexible drive rope at both ends differs by k times, then (k-1)Tlsinα=Q, and the tension of the flexible drive rope is solved as:

[0058]

[0059] According to the structure of the differential winch, k is decomposed into k1 and k2. Let R1 be the radius of the pulley with a smaller outer diameter, and R2 be the radius of the pulley with a larger outer diameter. For a single winch, the torque required by the motor satisfies the following relationship:

[0060] Q n -k1k2TR1+j1TR1-j1TR2+TR2=0

[0061] It can be solved as:

[0062]

[0063] If the differential capstan is not used, the solution is:

[0064]

[0065] Compare to Q n and Q n ′It can be found that the main contribution items are k1k2R, Q n In the middle is R1, Q n ' is R2, when R1 is small, Q n Can be significantly smaller than Q n ', that is, further reducing the torque requirement of the drive motor 3-1.

[0066] The process of the rope drive mechanism 3 of the present application driving the mechanical arm to bend is as follows: first, the driving motor 3-1 drives the differential winch to rotate through the reducer 3-2, and the differential winch generates a force on the rope entry end of the flexible driving rope 3-7, thereby realizing the tensioning of the rope entry end. Due to the change in the angle between the two adjacent segmented arms 1, the length of the quadrilateral flexible driving rope 3-7 in the tensioned state changes. In order to ensure that the rope is always in a tensioned state, the constant force springs 3-6 in the two rope tensioning assemblies generate a force on their respective pulleys 3-5, one of which generates a force on the rope entry end and the rope exit end of the flexible driving rope 3-7 on the differential winch, and the other pulley 3-5 generates a force on the rope exit end of the guide wheel 3-4 and the rope entry section, thereby realizing the lengthening or shortening of this rope section to adapt to the change in the length of the quadrilateral flexible driving rope 3-7 used to provide tension for the mechanical arm; the two segmented arms 1 are connected The joint 2 rotates symmetrically about the central axis toward the side where the tension of the flexible drive rope 3-7 is greater, thereby realizing the bending of the robotic arm in each joint drive module; in each joint drive module, when the two adjacent segmented arms 1 are in an extended state, the required length of the flexible drive rope 3-7 is the longest, the distance between the first pulley 3-5 and the differential winch is minimized, the spring 3-6 is in an extended state and is stretched to its longest, and the spring 3-6 always generates tension on the flexible drive rope 3-7 through the first pulley 3-5, thereby changing the distance between the first pulley 3-5 and the differential winch; as the angle between the two adjacent segmented arms 1 becomes smaller, the length of the flexible drive rope 3-7 gradually decreases until the length of the flexible drive rope 3-7 reaches a minimum when the two adjacent segmented arms 1 are brought together, and in this process, the length of the spring 3-6 gradually decreases, so that the distance between the first pulley 3-5 and the differential winch gradually increases, and the tension of the flexible drive rope 3-7 is always maintained.

[0067] See also Fig.16 The lateral support mechanism 4 includes a transverse support 4-1 and a sliding traction assembly. The sliding traction assembly is installed on the middle hinge plate 2-1 and the transverse support 4-1 at the same time. The transverse support 4-1 is a rectangular frame. The upper and lower ends of the transverse support 4-1 are respectively provided with slide rails 4-1-1 along its length direction. The middle hinge plate 2-1 and the transverse support 4-1 cooperate with the slide groove 2-1-1 and the slide rail 4-1-1 and realize the linear movement and fixation between the transverse support 4-1 and the connecting joint 2 along its own length direction under the traction force of the sliding traction assembly.

[0068] Furthermore, the two ends of the cross brace 4-1 are provided with second pulleys 4-1-2 for supporting and guiding the flexible driving rope 3-7 in the rope drive mechanism 3, that is, Figure 7As shown, after the flexible drive rope 3-7 passes around the pulley 3-5 in one group of cable tensioning assemblies, the two ends of the cable respectively pass around the two winches with different outer diameters on the differential winch in reverse, and then pass through the second pulleys 4-1-2 at both ends of the cross brace 4-1 respectively, and the two ends of the cable pass around the guide wheel 3-4 in reverse, and then are put on the pulley 3-5 in another group of cable tensioning assemblies.

[0069] Furthermore, the sliding traction assembly includes two motors 4-2, two worm gear reducers 4-3, two third capstans 4-4, two fourth capstans and two ropes 4-6; the two motors 4-2, worm gear reducers 4-3, third capstans 4-4 and ropes 4-6 are respectively mounted on the upper and lower end surfaces of the middle hinge plate 2-1, the output end of the motor 4-2 is connected to the input end of the worm gear reducer 4-3, the output end of the worm gear reducer 4-3 is fixedly connected to the third capstan 4-4, the two fourth capstans are respectively mounted on the two end portions of the cross brace 4-1, one end of the rope 4-6 is wound around the third capstan 4-4, the other end of the rope 4-6 is fixed on the fourth capstan and tensioned; the motor 4-2 drives the third capstan 4-4 to rotate through the worm gear reducer 4-3, thereby realizing the rope 4-6 on the third capstan 4-4 The rope is gathered and released; the cross brace 4-1 is moved by the gathering and release of the two ropes 4-6.

[0070] Since the cross-section of the mechanical arm formed by the rope-driven mechanism, the lateral support mechanism 4 and the joint arm 1 in the present application is relatively large, there is a possibility of collision with other flying asteroids during the capture of non-cooperative targets. In order to avoid flying asteroids, one of the ropes 4-6 in the present application performs a rope-retracting action, while the other rope 4-6 performs a rope-releasing action. The rope-retracting length is the same as the rope-releasing length. Since the position of the mechanical arm remains fixed, the retracted rope generates a pulling force on the cross brace 4-1, thereby realizing the linear movement of the cross brace 4-1. The cross brace 4-1 drives the flexible driving ropes 3-7 supported at both ends to move, thereby realizing the avoidance function.

[0071] Also, see Fig.14 , when the robot arm transitions from the folded state to the unfolded state and the driving force of the rope drive mechanism is ensured, the cross brace 4-1 and the connecting joint 2 move linearly under the traction force of the sliding traction assembly, so that the connecting joint 2 is in the middle position of the cross brace 4-1. At this time, the torque required by the robot arm connecting joint 2 is the smallest, for the following reasons:

[0072] Assume that the length of the cross brace 4-1 is L, the torque required to drive each joint of the robot arm is Q, and the angle between the joint arm and the flexible driving rope is α, then it is obvious that:

[0073]

[0074] Among them, T1 and T2 are the tension of the flexible driving rope on both sides of the differential winch, and Lcosα is the length of the vertical line from the joint to the flexible driving rope. Figure 6 As shown by the dotted line, it is obvious that when the length of the arm 1 remains unchanged, the larger the cross brace length L is, the longer the vertical line length is, so the smaller (T1-T2) is. (T1-T2) is provided by the differential winch and the drive motor, so the torque requirement for the drive motor is reduced, achieving the low mass requirement of the drive motor, and further realizing the purpose of lightweighting the robotic arm.

[0075] When the robot arm transitions from the extended state to the retracted state, see Fig.15 The sliding traction assembly pulls the cross brace 4-1 to move, and finally the connecting joint 2 is at the end of the cross brace 4-1. The two adjacent segmented arms 1 are completely folded under the action of the connecting joint 2, so that all the segmented arms 1 are gathered into a row, and each cross brace 4-1 is between two adjacent segmented arms 1, which greatly reduces the packaging volume of the space robot arm.

[0076] The working process of the present invention is further described below to further demonstrate the working principle and advantages of the present invention:

[0077] Step 1: The robot arm of the present application is initially in a fully gathered state. Figure 1 In the state shown in FIG. 1 , when a larger non-cooperative target needs to be grasped, the angle between the two adjacent segment arms 1 in the joint drive module is calculated according to the position of the grasped target, thereby determining the extension length of the robot arm and the position of the end of the robot arm; since the two adjacent segment arms 1 rotate symmetrically with the cross brace 4-1 as the center dividing plane, the two adjacent joint drive modules share the same segment arm 1, and through Figure 2 and Figure 3 It can be seen that all the cross braces 4 - 1 are always in a parallel state, so the angles between the two segmented arms 1 in all the joint drive modules are the same, and only the angle at one connection joint needs to be calculated.

[0078] Step 2, according to the above calculation results, the driving motor 3-1 drives the rotation of the differential winch through the reducer 3-2, and at the same time, the connecting joint 2 and the cross brace 4-1 move under the traction force of the sliding traction assembly, and the connecting joint is in the middle position of the cross brace 4-1 and remains stationary; the differential winch generates a force on the flexible driving rope 3-7 through friction, so that one end of the flexible driving rope 3-7 is in a winding state, and the other end of the flexible driving rope 3-7 is in a releasing state, and the two segmented arms 1 rotate symmetrically with the connecting joint 2 as the center axis toward the side with greater tension of the flexible driving rope 3-7, so as to realize the deployment of the robotic arm.

[0079] Step 3, when the non-cooperative target is captured, the robot arm recovers from the deployed state to the gathered state, and the driving motor 3-1 drives the differential winch in the reverse direction through the reducer 3-2. At the same time, the connecting joint 2 and the cross brace 4-1 move in the reverse direction under the traction force of the sliding traction assembly, and the connecting joint 2 no longer moves when it is at the end of the cross brace 4-1; the differential winch again generates a reverse force on the flexible driving rope 3-7 through friction, so that the other end of the flexible driving rope 3-7 is in a releasing state, and one end of the flexible driving rope 3-7 is in a reeling state, and the two segmented arms 1 rotate symmetrically with the connecting joint 2 as the center axis toward the side with greater tension of the flexible driving rope 3-7, thereby realizing the gathering of the robot arm.

[0080] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be used in other described embodiments.

Claims

1. A large-scale, lightweight, tension-driven space manipulator, characterized in that: It comprises a plurality of segmented arms (1), a plurality of connecting joints (2), a plurality of rope drive mechanisms (3) and a plurality of transverse support mechanisms (4); the plurality of segmented arms (1) are connected in series to form a mechanical arm, each two adjacent segmented arms (1) are hingedly connected via a connecting joint (2), and each two adjacent segmented arms (1) are driven via a rope drive mechanism (3) to achieve bending at the joint; each connecting joint (2) is slidably connected to a transverse support mechanism (4), and the two adjacent segmented arms (1) are respectively located on both sides of the transverse support mechanism (4); the two adjacent segmented arms (1), a connecting joint (2), a rope drive mechanism (3) and a transverse support mechanism (4) constitute a joint drive module; The rope drive mechanism (3) comprises a drive motor (3-1), a reducer (3-2), a winch (3-3), a guide wheel (3-4), a flexible drive rope (3-7) and two sets of flexible drive rope tensioning components. The drive motor (3-1), the reducer (3-2), the winch (3-3) and one set of flexible drive rope tensioning components are installed on one of the segment arms (1) and are arranged at an end away from the connection joint (2). The output end of the drive motor (3-1) is connected to the input end of the reducer (3-2), the output end of the reducer (3-2) is fixedly connected to the winch (3-3), the guide wheel (3-4) and the other set of flexible drive rope tensioning components are installed on the link arm (1). The flexible drive rope (3-7) is mounted on the other segmented arm (1) and is arranged at one end away from the connection joint (2); the flexible drive rope (3-7) is annular, and after the flexible drive rope (3-7) passes around one of the sets of flexible drive rope tensioning assemblies, the two ends of the flexible drive rope (3-7) pass around the winch (3-3) in the reverse direction and pass through the two ends of the transverse support mechanism (4) respectively, and finally the two ends of the flexible drive rope (3-7) pass around the guide wheel (3-4) in the reverse direction and are sleeved on the other set of flexible drive rope tensioning assemblies; the flexible drive rope (3-7) forms a quadrilateral structure under the support of the transverse support mechanism (4), and is always in a tensioned state under the action of the two sets of flexible drive rope tensioning assemblies; The flexible driving rope (3-7) is a cable; the winch (3-3) is a differential winch, which is composed of two winches with different outer diameters that are coaxially fixedly connected. The driving motor (3-1) drives the differential winch to rotate through the reducer (3-2). The differential winch generates a force on the flexible driving rope (3-7) through friction, so that one end of the flexible driving rope (3-7) is in a reeling state and the other end of the flexible driving rope (3-7) is in a releasing state. The two segmented arms (1) rotate symmetrically with the connecting joint (2) as the central axis toward the side with greater tension of the flexible driving rope (3-7), thereby realizing the deployment of the mechanical arm; Each set of flexible drive rope tensioning components comprises a first pulley (3-5) and a spring (3-6), one end of the spring (3-6) is fixedly connected to the joint arm (1), and the other end of the spring (3-6) is connected to the first pulley (3-5) via a pulley bracket.

2. A large-scale, lightweight, tension-driven space manipulator according to claim 1, characterized in that: The connecting joint (2) comprises a middle hinge plate (2-1), two sandwich hinge plates (2-2) and two outer hinge plates (2-3); the two sandwich hinge plates (2-2) and the two outer hinge plates (2-3) are symmetrically arranged on both sides of the middle hinge plate (2-1); the outer hinge plates (2-3) and the sandwich hinge plates (2-2) on the same side are hingedly connected; the two sandwich hinge plates (2-2) are hingedly connected to the middle hinge plate (2-1) via the same pin shaft; the two outer hinge plates (2-3) are fixedly connected to two adjacent segment arms (1) respectively; and the middle hinge plate (2-1) is slidably connected to the lateral support mechanism (4).

3. A large-scale, lightweight, tension-driven space manipulator according to claim 2, characterized in that: A clamping block (2-6) and a clamping slot (2-7) are provided between the outer hinge plate (2-3) and the sandwich hinge plate (2-2), and the two are fixedly connected through the cooperation of the clamping block (2-6) and the clamping slot (2-7).

4. The large-scale, lightweight, tension-driven space robot according to claim 2, characterized in that: The middle hinge plate (2-1) is an I-shaped structure, and a sliding groove (2-1-1) is respectively provided at the bottom and the top of the middle hinge plate (2-1).

5. A large-scale, lightweight, tension-driven space manipulator according to claim 4, characterized in that: The lateral support mechanism (4) comprises a transverse support (4-1) and a sliding traction assembly. The sliding traction assembly is installed on the middle hinge plate (2-1) and the transverse support (4-1) at the same time. The transverse support (4-1) is a rectangular frame. The upper and lower ends of the transverse support (4-1) are respectively provided with slide rails (4-1-1) along the length direction thereof. The middle hinge plate (2-1) and the transverse support (4-1) cooperate with each other through the slide groove (2-1-1) and the slide rail (4-1-1) and under the traction force of the sliding traction assembly, the transverse support (4-1) and the connecting joint (2) can move linearly and be fixed along their own length direction.

6. A large-scale, lightweight, tension-driven space manipulator according to claim 5, characterized in that: When the mechanical arm is working, the connecting joint (2) is located at the middle position of the cross brace (4-1).

7. The large-scale, lightweight, tension-driven space manipulator according to claim 5, characterized in that: Second pulleys (4-1-2) are provided at both ends of the cross brace (4-1) and are used to support and guide the flexible driving rope (3-7) in the rope driving mechanism (3).

8. The large-scale, lightweight, tension-driven space robot according to claim 7, characterized in that: The sliding traction assembly comprises two motors (4-2), two worm gear reducers (4-3), two third winches (4-4) and two ropes (4-6); the two motors (4-2), the worm gear reducers (4-3) and the third winches (4-4) are respectively mounted on the upper and lower end surfaces of the middle hinge plate (2-1); the output end of the motor (4-2) is connected to the input end of the worm gear reducer (4-3); the output end of the worm gear reducer (4-3) is fixedly connected to the third winch (4-4); one end of the rope (4-6) is wound around the third winch (4-4); the other end of the rope (4-6) is fixed to the end of the cross brace (4-1) and tensioned; the cross brace (4-1) is moved by the two ropes (4-6) being retracted and released.

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