Highly dexterous nine-degree-of-freedom hybrid robot for human-robot contact interaction

Abstract

The application discloses a high-skill nine-degree-of-freedom hybrid robot for human-machine contact interaction, which comprises a main parallel mechanism, a sub-parallel adjustment module and a variable stiffness module; the main parallel mechanism comprises a bottom plate, three groups of rotary drivers, platforms A and B and three groups of branch chains; the three groups of branch chains are connected with the platforms A and B and the three groups of rotary drivers respectively; three groups of modules of the variable stiffness module are matched with the three groups of rotary drivers, and variable stiffness sliders of the three groups of modules are connected with variable stiffness motors and heart slider crank mechanism groups respectively; the heart slider crank mechanism groups are connected with the branch chains of the main parallel mechanism; a rotary frame top end of the sub-parallel adjustment module is provided with four rotary drivers, and one side of the rotary frame top end is connected with the platform A; four groups of branch chains of the sub-parallel adjustment module are all provided with electromagnetic switching modules and arc-shaped connecting rods, and upper and lower ends of the four groups of branch chains are connected with the four rotary drivers and a terminal platform respectively. The application adopts an innovative hybrid basic framework, and cooperates with a variable stiffness and electromagnetic driving capacity system, so that the combination of large-space skillful positioning and safe compliant interaction is realized.

Description

Technical Field

[0001] This invention relates to the field of robot mechanism design, and in particular to the design of a highly dexterous nine-DOF hybrid robot for human-robot interaction. Background Technology

[0002] The statements in this section are merely background information relating to this disclosure, and these statements may constitute prior art. In the process of developing this invention, the inventors discovered at least the following problems in the prior art.

[0003] In human-machine interaction scenarios such as physical contact interaction, surface flaw detection, and rehabilitation therapy, robots need to make direct and close physical contact with the human body or complex curved surfaces. These scenarios place extremely high demands on the robot's end effector dexterity, motion compliance, force control precision, and human-machine interaction safety. However, traditional rigid serial and parallel robots, such as those described in patent application number 202423323853.7 entitled "Simulated Massage Device and Rehabilitation Therapy Robot," have many limitations in practical applications. Their purely rigid structures lack operational compliance, are prone to causing impact injuries to the human body, struggle to balance end effector dexterity and load-bearing capacity, and cannot achieve passive compliant protection under sudden impacts. Specifically, existing human-machine contact interaction robots mainly face the following four core technological bottlenecks:

[0004] (1) Limited pose adjustment range and prominent singularity problems make it difficult to adapt to high curvature surfaces. The pose adjustment range of traditional robots is limited, making it difficult to adapt to the large-angle fit requirements of the human body surface with high curvature. When making large-angle pose adjustments, it is very easy to fall into singularity, resulting in control instability, low pose adjustment accuracy and efficiency; and due to insufficient pose adjustment capability, the equipment needs to be repeatedly positioned, which seriously affects the continuity of operation and overall work efficiency.

[0005] (2) Lack of motion redundancy and single force control mode, lacking anthropomorphic operation characteristics. Existing force control methods cannot match the complex mechanical characteristics of human soft tissues, and the system lacks sufficient degrees of freedom and motion redundancy, making it difficult to simulate the flexible movement characteristics of the human wrist joint. Existing equipment often lacks an effective switching mechanism between active and passive modes, making it difficult to achieve stable constant force tracking and meet the needs of complex active interaction. This not only poses a safety hazard of pressure damage to human tissues, but also significantly increases the difficulty of actual operation and the risk of misoperation.

[0006] (3) The structural stiffness and the weight of the moving parts are difficult to coordinate, resulting in a dilemma in lightweight design. In order to ensure operational stability and load-bearing capacity, the equipment usually needs to have high stiffness, which makes the moving parts heavy, with high inertia and energy consumption. This is contrary to the principle of lightweight and low inertia required for human contact interaction terminals, resulting in the existing equipment being trapped in the design dilemma of "high stiffness must be high weight", which is difficult to adapt to high-speed and high-frequency interactive operation scenarios;

[0007] (4) Fixed interaction stiffness and lack of compliant protection, resulting in insufficient environmental adaptability and safety performance. The interaction stiffness of traditional rigid robots is not adjustable, and it is impossible to flexibly adjust the interaction stiffness according to the actual working scenario (such as the tissue hardness of different parts and the requirements of different physiotherapy techniques). Due to the lack of adjustable compliant drive structure and passive compliant protection mechanism, the equipment has poor environmental adaptability, and the safety of use in the human-computer interaction process is difficult to be fundamentally guaranteed.

[0008] The main problem this invention addresses is how to meet the comprehensive requirements of large-angle flexible posture adjustment in human-computer interaction scenarios, while simultaneously satisfying the requirements of highly redundant anthropomorphic operation, lightweight yet high rigidity, and safety and compliance. Summary of the Invention

[0009] In view of the above problems, the purpose of this invention is to solve some of the problems in the prior art, or at least alleviate these problems.

[0010] Highly dexterous nine-DOF hybrid robots designed for human-computer interaction include:

[0011] The main parallel mechanism includes a mounting bracket, a moving platform, and a main parallel branch chain assembly;

[0012] The mounting bracket includes a base plate and three sets of identical rotary actuators fixed on the base plate. Each set of rotary actuators includes two rotary actuators arranged coaxially. The first set of rotary actuators and the second set of actuators are symmetrically arranged on the left and right sides of the base plate, and the third set of rotary actuators is arranged in the middle of the base plate.

[0013] The moving platform includes platform A, platform B, connector A, connector B, and connector C; platform A and platform B are connected by a sliding joint, and platform B is connected to connector C by a revolute joint; a gear and rack assembly is provided between platform A and platform B to convert the relative movement of the two platforms into rotation; the first ends of connectors A and B are respectively connected to the left and right sides of platform A by revolute joints, and the two sides of the second ends are respectively connected to one end of universal joint A and universal joint B by revolute joints.

[0014] The main parallel branch chain group includes three branches with identical structures, adapted to the three sets of rotary actuators; each branch chain includes pulley A, pulley B, pulley C, pulley D, connecting rod I, and a first link group and a second link group that respectively form two sets of parallelograms; the first end of the connecting rod I is connected to the first end of the first link group and the first end of the second link group through a revolute joint; the second end of the connecting rod I of the three branches is connected to the universal joint A, universal joint B and connector C through a revolute joint; pulleys A and C are fixed on the rotating shaft of each set of rotary actuators of the mounting bracket, and are connected to pulleys B and D through a synchronous belt; pulley B is fixed to the second end of the first link group, and pulley D is connected to the second end of the second link group through connecting rod B and a revolute joint;

[0015] The sub-parallel adjustment module includes a rotating frame, a sub-parallel branch chain group, and an end platform. Four rotating actuators are fixed to the top of the rotating frame. One side of the rotating frame is connected to platform A via a revolute joint, and four electromagnetic integrated slider guide rails are fixed to its middle section. The sub-parallel branch chain group includes four sets of identical branches symmetrically arranged on the outside of the rotating frame. Each set of branches includes an electromagnetic switching module and an arc-shaped connecting rod. The upper end of the electromagnetic switching module is connected to one of the rotating actuators of the rotating frame via a screw and the electromagnetic integrated slider guide rail, and the lower end is connected to the first end of the arc-shaped connecting rod via a revolute joint. The second end of the arc-shaped connecting rod is connected to an end connector located at the upper end of the end platform via a revolute joint. An end probe is installed at the lower end of the end platform.

[0016] A highly dexterous nine-DOF hybrid robot for human-machine interaction also includes a variable stiffness module; the variable stiffness module comprises three modules adapted to the three sets of rotary actuators of the mounting bracket; each module includes a centering slider-crank mechanism, a variable stiffness slider, and a variable stiffness motor; the variable stiffness motor is fixed to the base plate; each set of rotary actuators of the mounting bracket has two guide rails arranged in the same direction behind it, and the guide rails are fixed to the base plate; the variable stiffness slider is connected to the base plate through a sliding joint and is connected to the rotating shaft of the variable stiffness motor through a screw; The centering slider-crank mechanism assembly includes a first set of centering slider-crank mechanisms and a second set of slider-crank mechanisms symmetrically arranged, each consisting of two symmetrically arranged sets of centering slider-crank mechanisms. The slider end of each centering slider-crank mechanism assembly is connected to the guide rail via a sliding joint and to the variable stiffness slider via a spring. The connecting rod end of the first set of centering slider-crank mechanisms is connected to pulley A via a revolute joint, and the connecting rod end of the second set of centering slider-crank mechanisms is connected to pulley C via a revolute joint. The electromagnetic switching module can effectively switch between active and passive modes by turning the power on and off.

[0017] Furthermore, the first set of aligning slider-crank mechanisms includes slider A, slider B, L-shaped connecting rod J, and connecting rod JⅡ; the second set of aligning slider-crank mechanisms includes slider C, slider D, L-shaped connecting rod K, and connecting rod KⅡ; slider A, slider B, slider C, and slider D are respectively connected to the guide rail via sliding joints, and are respectively connected to the variable stiffness slider via springs; one end of L-shaped connecting rod J and connecting rod JⅡ are respectively connected to slider A and slider B via revolute joints, and the other end is connected to pulley A via revolute joints; one end of L-shaped connecting rod K and connecting rod KⅡ are respectively connected to slider C and slider D via revolute joints, and the other end is connected to pulley C via revolute joints.

[0018] Furthermore, the gear and rack assembly of the moving platform includes a meshing gear and a rack; platform A is connected to the gear via a revolute joint, and platform B is fixedly connected to the rack; the axes of the revolute joints on connector A are perpendicular to each other; the axes of the revolute joints on connector B are perpendicular to each other; one side of the rotating frame is fixedly connected to the gear.

[0019] Furthermore, the first linkage group includes linkages A, C, D, and E connected by revolute joints parallel to each other's axes, forming a first set of parallelograms; the pulley B is fixed to linkage A; linkage A is connected to the base plate via a revolute joint; the second linkage group includes linkages F, G, and H connected sequentially by revolute joints parallel to each other's axes, forming a second set of parallelograms; the pulley D is fixed to linkage B, and together they are connected to linkage A via a revolute joint; linkage B is connected to linkage F via a revolute joint; linkage I is connected to linkages E and H via revolute joints respectively.

[0020] Furthermore, the axes of the revolute joints on the first and second sets of parallelograms are both perpendicular to the axis of the revolute joint between the connecting rod A and the base plate; the revolute joint between the connecting rod B and the connecting rod F, and the revolute joint between the connecting rod I and the connecting rods E and H, are all parallel to the axis of the revolute joint between the connecting rod A and the base plate.

[0021] Furthermore, the electromagnetic switching module includes an electromagnetic integrated slider and a push rod; the electromagnetic integrated slider is connected to the electromagnetic integrated slider guide rail via a sliding joint, and is connected to the rotation shaft of the rotation driver of the rotating frame via a screw; the push rod is connected to the electromagnetic integrated slider via a sliding joint, and a spring is provided between the two; a magnetic block is fixed at the lower end of the push rod, and it is connected to the first end of the arc-shaped connecting rod via a rotating joint; a coil is wound around the outer side of the electromagnetic integrated slider.

[0022] Furthermore, in the sub-parallel branch chain group, the two branches arranged symmetrically about the central axis of the end platform have their push rods and arc-shaped connecting rods connected by a rotating joint axis that coincides with each other in the initial position and remains parallel after movement; the second end of the arc-shaped connecting rod is connected to one end of the end connector through a rotating joint.

[0023] Furthermore, the end platform includes end platform A and end platform B; end platform A is connected to end platform B via a revolute joint; the two sets of branches of the sub-parallel branch group are symmetrically arranged around the central axis of the end platform, and the other end of their end connectors are connected to the two sides of end platform A or end platform B respectively via revolute joints, and the axes of the revolute joints coincide with each other; the end probe is mounted on end platform A.

[0024] Furthermore, the axis of the rotating joint connecting the end connectors of the four sets of branches of the sub-parallel branch group and the two sides of the end platform A or end platform B, as well as the axis of the rotating joint connecting the end platform A and end platform B, intersect at a point.

[0025] The present invention has the following beneficial effects:

[0026] (1) Wide range of flexible posture adjustment. The machine adopts a parallel-parallel hybrid structure, which has an ultra-large angle omnidirectional posture adjustment capability. It can closely fit various high curvature parts of the human body, reduce repeated positioning of equipment, and effectively improve the continuity of operation and overall work efficiency.

[0027] (2) Sufficient motion redundancy and human-like operation. The whole machine integrates multiple degrees of freedom to form a highly redundant motion system. With the mode switching function and multiple springs, it can realize various operation modes such as constant force tracking and active interaction. The motion mode conforms to the characteristics of the human wrist joint. The sub-parallel adjustment module has an electromagnetic switching function, which can change between active and passive modes. This allows the whole system to use the passive mode for constant force tracking and to change stiffness through active posture adjustment. The operation conforms to the human body's motion intuition and is more practical.

[0028] (3) Achieving a balance between lightweight and high rigidity. The drive and functional units are arranged at the rear, and the moving parts adopt a lightweight structure, which effectively reduces the mass of the moving parts and reduces inertia and energy consumption. Relying on the mechanical characteristics of the parallel structure, the whole machine still maintains excellent rigidity on the basis of lightweight, making it suitable for high-speed and high-frequency operation scenarios.

[0029] (4) It combines variable stiffness characteristics with adaptive safety performance. Equipped with an adjustable compliant drive structure, it can flexibly adjust the interaction stiffness according to the actual working scenario and usage requirements, and has good environmental adaptability, which greatly improves the safety of use in the human-computer interaction process.

[0030] Through the synergistic effect of the above improvements, the present invention can meet the comprehensive requirements of large-angle flexible posture adjustment in human-computer contact interaction scenarios, as well as high redundancy anthropomorphic operation, lightweight and high rigidity, and safety and compliance. Thus, it can be efficiently applied in human-computer contact interaction scenarios such as physical contact interaction, surface flaw detection, and rehabilitation therapy. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0032] Figure 2 A schematic diagram of the structure for installing the bracket;

[0033] Figure 3 This is a structural diagram of the moving platform;

[0034] Figure 4 A schematic diagram of the connection between the rack and gear on the moving platform;

[0035] Figure 5 A schematic diagram of the main parallel branch chain group;

[0036] Figure 6 A schematic diagram of the structure of a single branch in a main parallel branch group;

[0037] Figure 7 This is a schematic diagram of the overall structure of the variable stiffness module.

[0038] Figure 8 This is a structural schematic diagram of a single variable stiffness module;

[0039] Figure 9 A schematic diagram of a symmetrically arranged, concentric slider-crank mechanism on a variable stiffness module;

[0040] Figure 10 A schematic diagram of the sub-parallel adjustment module;

[0041] Figure 11 A schematic diagram showing the connection between a single branch of the sub-parallel module and the electromagnetic switching module;

[0042] Figure 12 A schematic diagram showing the connection between the sub-parallel branch chain group and the end platform;

[0043] Figure 13 This is a schematic diagram of the end-platform structure;

[0044] Figure 14 This is a schematic diagram illustrating the use of the present invention.

[0045] Wherein: 1-Mounting bracket; 11-Base plate; 12-Guide rail; 13-First rotary drive; 14-Second rotary drive; 15-Third rotary drive; 16-Fourth rotary drive; 17-Fifth rotary drive; 18-Sixth rotary drive; 2-Moving platform; 21-Platform A; 22-Platform B; 23-Connector A; 24-Connector B; 25-Connector C; 26-Universal shaft A; 27-Universal shaft B; 28-Gear; 29-Rack; 3-Main parallel chain assembly; 31-Pulley A; 32-Pulley B; 33-Pulley C; 34-Pulley D; 35-Connecting rod A; 36-Connecting rod B; 37-Connecting rod C; 38-Connecting rod D; 39-Connecting rod E; 310-Connecting rod F; 311-Connecting rod G; 312-Connecting rod H; 313-Connecting rod 1; 4-Variable stiffness module; 41-Slider A; 42-Slider B; 43-Slider C; 44-Slider D; 45-L-shaped connecting rod J; 46-Connecting rod JⅡ; 47-L-shaped connecting rod K; 48-Connecting rod KⅡ; 49-Variable stiffness slider; 410-Variable stiffness motor; 411-Screw; 5-Sub-parallel adjustment module; 51-Rotating frame; 52-Electromagnetic integrated slider guide rail; 53-Electromagnetic integrated slider; 54-Push rod; 55-Arc-shaped connecting rod; 56-End platform; 57-End connector; 58-End platform A; 59-End platform B; 510-End probe; 511-Magnetic block; 512-Coil; 513-Seventh rotary actuator; 514-Eighth rotary actuator; 515-Ninth rotary actuator; 516-Tenth rotary actuator; 6-Spring. Detailed Implementation

[0046] The present invention will be further described below with reference to the accompanying drawings. The embodiments of the present invention are only used to illustrate the present invention and not to limit the present invention. Various substitutions and modifications made based on ordinary technical knowledge and common practices in the art without departing from the technical concept of the present invention should be included within the scope of the present invention.

[0047] To overcome the aforementioned technical bottlenecks and meet the comprehensive requirements of human-computer interaction scenarios for large-angle dexterity posture adjustment, highly redundant humanoid operation, lightweight yet high rigidity, and safety and compliance, this invention proposes a highly dexterous nine-DOF hybrid robot for human-computer interaction. The specific solution is as follows.

[0048] like Figures 1 to 13 As shown, a highly dexterous nine-DOF hybrid robot for human-computer interaction includes:

[0049] The main parallel mechanism includes mounting bracket 1, moving platform 2, and main parallel branch chain group 3;

[0050] like Figure 2As shown, the mounting bracket 1 includes a base plate 11 and three sets of identical rotary actuators fixed on the base plate 11. Each set of rotary actuators includes two rotary actuators arranged coaxially. The first set of rotary actuators and the second set of actuators are symmetrically arranged on the left and right sides of the base plate 11, and the third set of rotary actuators is arranged in the middle of the base plate 11.

[0051] like Figure 3 As shown in Figure 4, the moving platform 2 includes platform A21, platform B22, connector A23, connector B24, and connector C25; platform A21 and platform B22 are connected by a sliding joint, and platform B22 is connected to connector C23 by a revolute joint; a gear and rack assembly is provided between platform A21 and platform B22 to convert the relative movement of platform B22 into the rotation of platform A21; the first ends of connectors A23 and B24 are respectively connected to the left and right sides of platform A21 by revolute joints, and the two sides of the second ends are respectively connected to one end of universal joint A26 and universal joint B27 by revolute joints.

[0052] like Figure 5 As shown in Figure 6, the main parallel branch chain group 3 includes three branches with identical structures, adapted to the three sets of rotary actuators; each branch chain includes pulley A31, pulley B32, pulley C33, pulley D34, connecting rod I313, and a first connecting rod group and a second connecting rod group that respectively form two sets of parallelograms; the first end of the connecting rod I313 is connected to the first end of the first connecting rod group and the first end of the second connecting rod group through a revolute joint; the second end of the connecting rod I313 of the three branches is connected to the universal joint A26, universal joint B27 and connector C23 through a revolute joint; pulleys A31 and C33 are fixed on the rotating shaft of each set of rotary actuators of the mounting bracket 1, and are connected to pulleys B32 and D34 through a synchronous belt; pulley B32 is fixed to the second end of the first connecting rod group, and pulley D34 is connected to the second end of the second connecting rod group through connecting rod B36 and a revolute joint.

[0053] like Figure 10As shown in Figures 11 or 12, the sub-parallel adjustment module 5 includes a rotating frame 51, a sub-parallel branch group, and an end platform 56. Four rotating actuators are fixed to the top of the rotating frame 51. One side of the rotating frame 51 is connected to the platform A21 via a revolute joint, and four electromagnetic integrated slider guide rails 52 are fixed to its middle section. The sub-parallel branch group includes four sets of identical branches symmetrically arranged on the outside of the rotating frame 51. Each set of branches includes an electromagnetic switching module and an arc-shaped connecting rod 55. The upper end of the electromagnetic switching module is connected to one of the rotating actuators of the rotating frame 51 via a screw and the electromagnetic integrated slider guide rail 52, and the lower end is connected to the first end of the arc-shaped connecting rod 55 via a revolute joint. The second end of the arc-shaped connecting rod 55 is connected to an end connector 57 located at the upper end of the end platform 56 via a revolute joint. An end probe 510 is installed at the lower end of the end platform 56.

[0054] Rotating frame 51 can be accessed Figure 10 The shaft in the rotating frame 51 is fixedly connected to the gear 28, while the shaft on the rotating frame 51 is connected to the platform A21 via a revolute joint. Thus, when the gear 28 rotates, it drives the rotating frame 51 to rotate relative to the platform A21. The rotating frame 51 and the electromagnetic integrated slider guide 52 are integrated as a single unit.

[0055] The above solution adopts a parallel-parallel hybrid structure, enabling the sub-parallel adjustment module 5 to achieve six degrees of freedom of movement in space. This gives the entire machine an ultra-wide omnidirectional attitude adjustment capability, allowing it to closely conform to various high-curvature parts of the human body, reducing repetitive positioning of the equipment, and effectively improving work continuity and overall work efficiency. Furthermore, the drive and functional units of this invention are all rear-mounted, allowing the moving parts to adopt a lightweight structure, effectively reducing the mass of the moving parts and lowering inertia and energy consumption. Relying on the mechanical properties of the parallel structure, the entire machine maintains excellent rigidity while being lightweight, making it suitable for high-speed, high-frequency operation scenarios.

[0056] To enhance the environmental adaptability of this invention and improve safety during human-computer interaction, a variable stiffness module 4 is installed behind the main parallel mechanism and connected to it to achieve changes in equivalent stiffness. Furthermore, the electromagnetic switching module in the sub-parallel adjustment module 5 is configured to effectively switch between active and passive modes by switching power on and off. Figure 5 As shown, the variable stiffness module 4 includes three modules adapted to the three sets of rotary actuators of the mounting bracket 1; each module includes a centering slider-crank mechanism group, a variable stiffness slider 49, and a variable stiffness motor 410; as shown Figure 1 As shown, the variable stiffness motor 410 is fixed on the base plate 11; each set of rotary drives of the mounting bracket 1 has two guide rails 12 arranged in the same direction, and the guide rails 12 are fixed on the base plate 11; as shown Figure 8As shown, the variable stiffness slider 49 is connected to the base plate 11 via a sliding joint and is connected to the rotating shaft of the variable stiffness motor 410 via a screw 411; the centering slider-crank mechanism group includes a first group of centering slider-crank mechanisms and a second group of slider-crank mechanisms symmetrically arranged, each consisting of two symmetrically arranged centering slider-crank mechanisms; the slider end of the centering slider-crank mechanism group is connected to the guide rail 12 via a sliding joint and to the variable stiffness slider 49 via a spring 6; the connecting rod end of the first group of centering slider-crank mechanisms is connected to the pulley A31 via a revolute joint, and the connecting rod end of the second group of centering slider-crank mechanisms is connected to the pulley C33 via a revolute joint.

[0057] In the passive mode when power is off, the sub-parallel adjustment module 5 can provide end-effector adaptation and buffering through its internal spring 6, which is useful for situations requiring precise tracking of a large trajectory. In the active mode when power is on, the sub-parallel adjustment module 5 can drive the end probe 510 to perform active tapping or pressing actions, and under the action of the four rotary actuators of the rotating frame 51, the end platform 56 can perform two-dimensional rotation in the plane, that is, it further has one translational degree of freedom and two rotational degrees of freedom.

[0058] This further enhances the spatial freedom of the sub-parallel adjustment module 5, which already possesses six degrees of freedom of motion, to nine degrees of freedom, thus expanding the range of flexible posture adjustment. The integrated multi-degree-of-freedom motion system, combined with mode switching functions and multiple springs, along with the active / passive mode changes of the electromagnetic switching function of the sub-parallel adjustment module, allows the entire system to perform constant force tracking in passive mode and variable stiffness through active posture adjustment. This makes operation more intuitive and responsive to human movement, enhancing its practicality. Furthermore, the rear placement of the variable stiffness module 4 further reduces the device's weight, making it more suitable for high-speed, high-frequency operation scenarios. It also allows for flexible adjustment of interaction stiffness based on actual operating scenarios and usage requirements, exhibiting excellent environmental adaptability and significantly improving safety during human-computer interaction.

[0059] like Figure 8As shown in Figure 9, the first set of concentric slider-crank mechanisms includes slider A41, slider B42, L-shaped connecting rod J45, and connecting rod JⅡ46; the second set of concentric slider-crank mechanisms includes slider C43, slider D44, L-shaped connecting rod K47, and connecting rod KⅡ48. Slider A41, slider B42, slider C43, and slider D44 are respectively connected to the guide rail 12 via sliding joints, and are respectively connected to the variable stiffness slider 49 via springs 6. One end of L-shaped connecting rod J45 and connecting rod JⅡ46 are respectively connected to slider A41 and slider B42 via rotating joints, and the other end is connected to pulley A31 via rotating joints. One end of L-shaped connecting rod K47 and connecting rod KⅡ48 are respectively connected to slider C43 and slider D44 via rotating joints, and the other end is connected to pulley C33 via rotating joints.

[0060] The sub-parallel adjustment module 5 includes a rotating frame 51, an end platform 56, and a sub-parallel branch group containing four branches: branch D, branch E, branch F, and branch G. Branches D, E, F, and G have identical structures and are symmetrically arranged on the outside of the rotating frame 51.

[0061] like Figure 10 As shown, the top of the rotating frame 51 is fixed with a seventh rotating driver 513, an eighth rotating driver 514, a ninth rotating driver 515, and a tenth rotating driver 516. One side of the rotating frame 51 is connected to the platform A21 of the moving platform 2 via a revolute joint and is fixed to the gear 28 of the moving platform 2, that is, the entire frame will rotate together with the gear 28.

[0062] like Figure 10As shown in Figure 11, the electromagnetic switching module includes an electromagnetic integrated slider 53 and a push rod 54. The electromagnetic integrated slider 53 is connected to the electromagnetic integrated slider guide rail 52 via a sliding joint, and is connected to the rotation shaft of the seventh rotary driver 513, the eighth rotary driver 514, the ninth rotary driver 515, or the tenth rotary driver 516 via a screw. The push rod 54 is connected to the electromagnetic integrated slider 53 via a sliding joint. One end of the push rod 54 is connected to a spring 6, and the other end of the spring 6 is connected to the electromagnetic integrated slider 53. A magnetic block 511 is also fixed at the lower end of the push rod 54, and is connected to the first end of the arc-shaped connecting rod 55 via a rotary joint. A coil 512 is wound around the outer side of the electromagnetic integrated slider 53. When energized, the electromagnetic integrated slider 53 attracts the magnetic block 511 on the push rod 54, making the electromagnetic integrated slider 53 and the push rod 54 a single unit with no relative movement, and the spring 6 is compressed. When de-energized, the two separate, and the electromagnetic integrated slider 53 and the push rod 54 can move relative to each other, stretching or compressing the spring 6. The electromagnetic integrated slider 53, push rod 54, spring 6, and magnetic block 511 constitute the electromagnetic switching module. The electromagnetic switching function of the parallel adjustment module 5 can switch between active and passive modes. With multiple springs, it can achieve various operating modes such as constant force tracking and active interaction, and the movement mode conforms to the characteristics of the human wrist joint.

[0063] Of course, other existing structures can also be used to achieve the same effect as the electromagnetic switching module. However, the above structure is simpler and can work well with the four sets of arc-shaped connecting rods 55 connected at the lower end to jointly control the end platform 56.

[0064] like Figure 12 As shown, in the sub-parallel branch group, the two branches symmetrically arranged around the central axis of the end platform 56 have rotary joint axes connecting the push rod 54 and the arc-shaped connecting rod 55. These axes coincide in the initial position and remain parallel after movement. The second end of the arc-shaped connecting rod 55 is connected to one end of the end connector 57 via a rotary joint. Specifically, in the initial position, for branches D and F, the rotary joint axes at the lower ends of the push rod 54 coincide and remain parallel after movement; similarly, for branches E and G, the rotary joint axes at the lower ends of the push rod 54 coincide and remain parallel after movement. This design allows branches D and F to form a connection similar to a symmetrical, concentric crank-slider mechanism, while branches E and G form another symmetrical, concentric crank-slider mechanism, thus improving the attitude adjustment capability in both rotational directions.

[0065] like Figure 13As shown, the end platform 56 includes end platform A58 and end platform B59; end platform A58 is connected to end platform B59 via a revolute joint; the two sets of branches of the sub-parallel branch group are symmetrically arranged about the central axis of the end platform 56, and the other end of their end connectors 57 are connected to both sides of end platform A58 or end platform B59 respectively via revolute joints, with the axes of the revolute joints coinciding with each other. The axes of the revolute joints connecting the end connectors 57 of the four sets of branches of the sub-parallel branch group to both sides of end platform A58 or end platform B59, and the axes of the revolute joints connecting end platform A58 and end platform B59, intersect at a point.

[0066] Specifically, for branches D and F, the other end of the end connector 57 is connected to both sides of the end platform A58 via a revolute joint, with the axes of the revolute joints coinciding; for branches E and G, the other end of the end connector is connected to both sides of the end platform B59 via a revolute joint, with the axes of the revolute joints coinciding; all these axes intersect at a single point. End platform A58 is connected to end platform B59 via a revolute joint, and the revolute joints intersect at the aforementioned intersection point.

[0067] The end probe 510 is mounted on the end platform A58.

[0068] In this invention, the mounting bracket 1 is mainly used to support other modules. It has three sets of rotary actuators, totaling six rotary actuators: a first rotary actuator 13, a second rotary actuator 14, a third rotary actuator 15, a fourth rotary actuator 16, a fifth rotary actuator 17, and a sixth rotary actuator 18. Figure 2 As shown, all are fixed on the base plate 11. The above rotary actuators are divided into three groups: the first group of actuators includes the first and second rotary actuators arranged coaxially, the second group of actuators includes the third and fourth rotary actuators arranged coaxially, and the third group of actuators includes the fifth and sixth rotary actuators arranged coaxially.

[0069] The gear and rack assembly of the moving platform 2, such as Figure 4 As shown, platform A21 is connected to gear 28 via a revolute joint, and platform B22 is fixedly connected to rack 29. Gear 28 and rack 29 mesh. When platform A21 slides relative to platform B22, the relative movement can be converted into rotation of gear 28 through the meshing relationship between rack and gear. The axes of the revolute joints on connector A23 are perpendicular to each other; the axes of the revolute joints on connector B23 are also perpendicular to each other.

[0070] The main parallel branch group 3 of the present invention includes three branches: branch A, branch B, and branch C. Branches A, B, and C have identical structures. Branches A and B are symmetrically arranged on the left and right sides of the base plate 11, while branch C is arranged in the middle of the base plate 11, each adapted to one of the three rotary actuators of the mounting bracket 1. Figure 5 As shown, pulleys A31 and C33 of branch A are respectively fixed to the rotating shafts of the first rotary driver 13 and the second rotary driver 14; pulleys A31 and C33 of branch B are respectively fixed to the rotating shafts of the third rotary driver 15 and the fourth rotary driver 16; and pulleys A31 and C33 of branch C are respectively fixed to the rotating shafts of the fifth rotary driver 17 and the sixth rotary driver 18. Figure 6 As shown, pulley A31 and pulley B32 are connected by a synchronous belt, and pulley C33 and pulley D34 are connected by a synchronous belt.

[0071] like Figure 5 As shown in Figure 6, the first linkage group includes connecting rods A35, C37, D38, and E39 connected by revolute joints parallel to each other's axes, forming a first set of parallelograms; pulley B32 is fixed to connecting rod A35; connecting rod A35 is connected to the base plate 11 via a revolute joint; the second linkage group includes connecting rods F310, G311, and H312 connected sequentially by revolute joints parallel to each other's axes, forming a second set of parallelograms; pulley D34 is fixed to connecting rod B36, and together they are connected to connecting rod A35 via a revolute joint; connecting rod B36 is connected to connecting rod F310 via a revolute joint; connecting rod I313 is connected to connecting rod E39 and connecting rod H312 via revolute joints respectively.

[0072] The axes of the revolute joints on the first and second sets of parallelograms are both perpendicular to the axis of the revolute joint between the connecting rod A35 and the base plate 11; the revolute joint between the connecting rod B36 and the connecting rod F310, and the revolute joints between the connecting rod I313 and the connecting rods E39 and H312 are all parallel to the axis of the revolute joint between the connecting rod A35 and the base plate 11.

[0073] The following are the motion principles of each component of this invention:

[0074] The main parallel mechanism is driven by a first rotary driver 13, a second rotary driver 14, a third rotary driver 15, a fourth rotary driver 16, a fifth rotary driver 17, and a sixth rotary driver 18, which control the movement of branches A, B, and C respectively. With the cooperation of the three branches, platform A21 of the moving platform 2 can achieve three-dimensional movement in space, as well as two rotations within the plane of platform A21. Specifically, when branch C translates relative to platform A21, this relative movement is converted into rotation of gear 28 through the transmission between rack 29 and gear 28. Since the rotating frame 51 of the sub-parallel adjustment module 5 is fixed to gear 28, the entire frame rotates along with gear 28. Therefore, under the action of the main parallel mechanism alone, the sub-parallel adjustment module 5 can achieve six degrees of freedom movement in space.

[0075] Variable stiffness module 4: The variable stiffness motor 410 adjusts the position of the variable stiffness slider 49 via the screw 411. When the variable stiffness slider 49 moves away from the variable stiffness motor 410, all springs 6 will shorten synchronously, increasing the elastic force and thus increasing the equivalent stiffness; when the variable stiffness slider 49 moves closer to the variable stiffness motor 410, all springs 6 will extend synchronously, decreasing the elastic force and thus decreasing the equivalent stiffness. Therefore, by changing the position of the variable stiffness slider 49, the length of the springs 6 can be changed, thereby changing the elastic force and achieving a change in equivalent stiffness.

[0076] Sub-parallel adjustment module 5: The movement of this module is related to the mode of the electromagnetic switching module.

[0077] 1. When the electromagnetic switching module is powered on, the electromagnetic integrated slider 53 attracts the magnetic block 511 on the push rod 54, making the electromagnetic integrated slider 53 and the push rod 54 a single unit. At this time, there is no relative movement between the electromagnetic integrated slider 53 and the push rod 54. The position of the end platform 56 is mainly controlled by the seventh rotary actuator 513, the eighth rotary actuator 514, the ninth rotary actuator 515, and the tenth rotary actuator control 516. When the actuators rotate in different directions, they change the position of the corresponding electromagnetic integrated slider 53. When all electromagnetic integrated sliders 53 rise or fall simultaneously, the position of the end platform 56 rises or falls accordingly. When some electromagnetic integrated sliders 53 rise and others fall, the end platform 56 performs a two-dimensional rotation in the plane. Therefore, the end platform 56 has one translational and two rotational degrees of freedom.

[0078] 2. When the electromagnetic switching module is powered off, the electromagnetic integrated slider 53 separates from the push rod 54 and is controlled by the spring 6. When the end platform 56 is subjected to external force, the spring 6 will first provide buffering, that is, the distance between the electromagnetic integrated slider 53 and the push rod 54 will change according to the magnitude of the external force. By adjusting the position of the electromagnetic integrated slider 53 through the driver, the elastic force of the spring can be further changed, that is, the interaction force between the end platform 56 and the environment can also be actively controlled.

[0079] like Figure 14 As shown, the working principles of the two main modes of this invention are as follows:

[0080] Main Mode 1: When precise tracking of a large-scale trajectory is required, the electromagnetic module of the sub-parallel adjustment module 5 is first switched to passive mode, that is, the electromagnetic integrated slider 53 is separated from the push rod 54, so that the push rod 54 can move accordingly according to the magnitude of the spring force to achieve end-effector adaptation and buffering effects; at the same time, the variable stiffness module 4 is adjusted to a suitable position, mainly for gravity compensation; at this time, the six rotary actuators of the main parallel mechanism play a major role in precisely controlling the positions of branches A, B, and C. Ultimately, the accuracy of trajectory tracking of the end probe 510 and the adaptability of the interaction force are achieved.

[0081] Main Mode 2: The end probe 510 performs active tapping or pressing actions. First, the electromagnetic module of the sub-parallel adjustment module 5 is switched to active mode, that is, the electromagnetic integrated slider 53 is fixedly connected to the push rod 54. The end probe 510 actively adjusts its posture through the four rotary motors of the sub-parallel module 5; at this time, the six rotary drivers of the main parallel mechanism play an auxiliary role, mainly cooperating with the variable stiffness module 4; the variable stiffness module 4 plays the main role, which can change the stiffness in time, and utilize the energy storage characteristics of the two pairs of springs, as well as the physical characteristics of the variable stiffness spring system itself, to perform compliant interaction at the end, so as to ensure the comfort and safety of tapping or pressing.

[0082] This invention proposes a highly dexterous nine-DOF hybrid robot for human-computer interaction. It employs an innovative hybrid architecture to ensure motion stability and load-bearing capacity, and is equipped with a probe system featuring variable stiffness and electromagnetic drive capabilities, thereby achieving a combination of dexterous positioning in large spaces and safe, compliant interaction. This invention simultaneously meets the comprehensive requirements of human-computer interaction scenarios for large-angle dexterous posture adjustment, highly redundant humanoid operation, lightweight yet high stiffness, and safe, compliant operation, making it more suitable for efficient application in human-computer interaction scenarios such as physical contact interaction, surface flaw detection, and rehabilitation therapy.

[0083] Unless otherwise specified, fixed connections can be riveting, welding, bolting, etc., while movable connections can be hinged, etc.

Claims

1. A highly dexterous nine-DOF hybrid robot for human-computer interaction, characterized in that, include: The main parallel mechanism includes a mounting bracket (1), a moving platform (2), and a main parallel branch group (3). The mounting bracket (1) includes a base plate (11) and three sets of rotary actuators with the same structure fixed on the base plate (11). Each set of rotary actuators includes two rotary actuators arranged coaxially. The first set of rotary actuators and the second set of actuators are symmetrically arranged on the left and right sides of the base plate (11), and the third set of rotary actuators is arranged in the middle of the base plate (11). The moving platform (2) includes platform A (21), platform B (22), connector A (23), connector B (24), and connector C (25); platform A (21) and platform B (22) are connected by a sliding joint, and platform B (22) is connected to connector C (23) by a rotating joint; a gear and rack assembly is provided between platform A (21) and platform B (22) to convert the relative movement of the two platforms into rotation; the first ends of connector A (23) and connector B (24) are respectively connected to the left and right sides of platform A (21) by rotating joints, and the two sides of the second ends are respectively connected to one end of universal joint A (26) and universal joint B (27) by rotating joints; The main parallel branch chain group (3) includes three branches with the same structure, adapted to the three sets of rotary actuators; each branch chain includes pulley A (31), pulley B (32), pulley C (33), pulley D (34), connecting rod I (313), and a first connecting rod group and a second connecting rod group that respectively form two sets of parallelograms; the first end of the connecting rod I (313) is connected to the first end of the first connecting rod group and the first end of the second connecting rod group through a revolute joint; the second ends of the connecting rod I (313) of the three branches are respectively The universal joints A (26), B (27), and C (23) are connected by a rotating joint; the pulleys A (31) and C (33) are fixed on the rotating shafts of each set of rotary drives of the mounting bracket (1) and are connected to the pulleys B (32) and D (34) respectively by a synchronous belt; the pulley B (32) is fixed to the second end of the first linkage group, and the pulley D (34) is connected to the second end of the second linkage group through the connecting rod B (36) and the rotating joint; The sub-parallel adjustment module (5) includes a rotating frame (51), a sub-parallel branch group, and an end platform (56). The top of the rotating frame (51) is fixed with four rotating actuators. One side of the rotating frame (51) is connected to the platform A (21) through a rotating joint, and four electromagnetic integrated slider guide rails (52) are fixed in the middle. The sub-parallel branch group includes four sets of branches with the same structure, symmetrically arranged on the outside of the rotating frame (51). Each set of branches includes an electromagnetic switching module and an arc-shaped connecting rod (55). The upper end of the electromagnetic switching module is connected to one of the rotating actuators of the rotating frame (51) through a screw and the electromagnetic integrated slider guide rail (52), and the lower end is connected to the first end of the arc-shaped connecting rod (55) through a rotating joint. The second end of the arc-shaped connecting rod (55) is connected to the end connector (57) located at the upper end of the end platform (56) through a rotating joint. An end probe (510) is installed at the lower end of the end platform (56).

2. The highly dexterous nine-DOF hybrid robot for human-computer interaction as described in claim 1, characterized in that, It also includes a variable stiffness module (4); the variable stiffness module (4) includes three modules adapted to the three sets of rotary actuators of the mounting bracket (1); each module includes a centering slider-crank mechanism group, a variable stiffness slider (49) and a variable stiffness motor (410); the variable stiffness motor (410) is fixed on the base plate (11); each set of rotary actuators of the mounting bracket (1) has two guide rails (12) arranged in the same direction, and the guide rails (12) are fixed on the base plate (11); the variable stiffness slider (49) is connected to the base plate (11) through a sliding joint, and is connected to the variable stiffness motor (410) through a screw (411). On the rotating shaft of 0); the centering slider crank mechanism group includes a first group of centering slider crank mechanisms and a second group of slider crank mechanisms arranged symmetrically, each consisting of two groups of symmetrically arranged centering slider crank mechanisms; the slider end of the centering slider crank mechanism group is connected to the guide rail (12) through a sliding joint, and is connected to the variable stiffness slider (49) through a spring (6); the connecting rod end of the first group of centering slider crank mechanisms is connected to the pulley A (31) through a rotating joint, and the connecting rod end of the second group of centering slider crank mechanisms is connected to the pulley C (33) through a rotating joint; the electromagnetic switching module can achieve effective switching between active and passive modes by turning on and off power.

3. The highly dexterous nine-DOF hybrid robot for human-computer interaction as described in claim 2, characterized in that, The first set of concentric slider-crank mechanisms includes slider A (41), slider B (42), L-shaped connecting rod J (45), and connecting rod JⅡ (46); the second set of concentric slider-crank mechanisms includes slider C (43), slider D (44), L-shaped connecting rod K (47), and connecting rod KⅡ (48); slider A (41), slider B (42), slider C (43), and slider D (44) are respectively connected to the guide rail (12) through sliding pairs, and respectively through springs ( 6) Connected to the variable stiffness slider (49); one end of the L-shaped connecting rod J (45) and connecting rod JⅡ (46) are respectively connected to the slider A (41) and slider B (42) through a rotating joint, and the other end is connected to the pulley A (31) through a rotating joint; one end of the L-shaped connecting rod K (47) and connecting rod KⅡ (48) are respectively connected to the slider C (43) and slider D (44) through a rotating joint, and the other end is connected to the pulley C (33) through a rotating joint.

4. The highly dexterous nine-DOF hybrid robot for human-computer interaction as described in claim 1, characterized in that, The gear and rack assembly of the moving platform (2) includes a meshing gear (28) and a rack (29); the platform A (21) is connected to the gear (28) via a rotating joint, and the platform B (22) is fixedly connected to the rack (29); the axes of the rotating joints on the connector A (23) are perpendicular to each other; the axes of the rotating joints on the connector B (23) are perpendicular to each other; one side of the rotating frame (51) is fixedly connected to the gear (28).

5. The highly dexterous nine-DOF hybrid robot for human-computer interaction as described in claim 1, characterized in that, The first linkage group includes linkages A (35), C (37), D (38), and E (39) connected by revolute joints parallel to each other on their axes, forming a first set of parallelograms; the pulley B (32) is fixed to linkage A (35); linkage A (35) is connected to the base plate (11) by a revolute joint; the second linkage group includes linkages F (310), G (311), and H (312) connected by revolute joints parallel to each other on their axes, forming a second set of parallelograms; the pulley D (34) is fixed to linkage B (36) and together connected to linkage A (35) by a revolute joint; linkage B (36) is connected to linkage F (310) by a revolute joint; linkage I (313) is connected to linkage E (39) and linkage H (312) by revolute joints respectively.

6. The highly dexterous nine-DOF hybrid robot for human-computer interaction as described in claim 5, characterized in that, The axes of the rotational joints on the first and second sets of parallelograms are perpendicular to the axis of the rotational joint between the connecting rod A (35) and the base plate (11); the rotational joint between the connecting rod B (36) and the connecting rod F (310), and the rotational joint between the connecting rod I (313) and the connecting rod E (39) and the connecting rod H (312) are all parallel to the axis of the rotational joint between the connecting rod A (35) and the base plate (11).

7. The highly dexterous nine-DOF hybrid robot for human-computer interaction according to claim 2, characterized in that, The electromagnetic switching module includes an electromagnetic integrated slider (53) and a push rod (54); the electromagnetic integrated slider (53) is connected to the electromagnetic integrated slider guide rail (52) through a sliding joint, and is connected to the rotation shaft of the rotation driver of the rotating frame (51) through the screw; the push rod (54) is connected to the electromagnetic integrated slider (53) through a sliding joint, and a spring (6) is provided between the two; a magnetic block (511) is fixed at the lower end of the push rod (54), and is connected to the first end of the arc-shaped connecting rod (55) through a rotating joint; a coil (512) is wound around the outside of the electromagnetic integrated slider (53).

8. The highly dexterous nine-DOF hybrid robot for human-computer interaction according to claim 7, characterized in that, The two sets of branches in the sub-parallel branch group are symmetrically arranged around the central axis of the end platform (56). The axis of the rotating joint connecting the push rod (54) and the arc-shaped connecting rod (55) coincides with each other in the initial position and always remains parallel after movement. The second end of the arc-shaped connecting rod (55) is connected to one end of the end connector (57) through a rotating joint.

9. The highly dexterous nine-DOF hybrid robot for human-computer interaction according to claim 7, characterized in that, The end platform (56) includes end platform A (58) and end platform B (59); end platform A (58) is connected to end platform B (59) through a rotating joint; the two sets of branches of the sub-parallel branch group are symmetrically arranged around the central axis of the end platform (56), and the other end of their end connectors (57) are connected to the two sides of end platform A (58) or end platform B (59) respectively through a rotating joint, and the axes of the rotating joints coincide with each other; the end probe (510) is installed on end platform A (58).

10. The highly dexterous nine-DOF hybrid robot for human-computer interaction according to claim 9, characterized in that, The end connectors (57) of the four branches of the sub-parallel branch group are connected to the rotating shafts of the two sides of the end platform A (58) or the end platform B (59), and the rotating shafts of the end platform A (58) and the end platform B (59) intersect at one point.

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