A high-rigidity hybrid configuration robot

Abstract

The application provides a high-rigidity hybrid robot, relates to the technical field of robots, and introduces a redundant actuator group based on a serial mechanical arm to form a hybrid robot, which can actively offset dynamic load deformation through multiple telescopic supporting rods of the redundant actuator group, and the rotating base is taken as a core support carrier, a hinged support is installed on the base to provide a fixed hinge point for the redundant actuator group; the base of the serial mechanical arm is rotatably installed on the rotating base and can rotate as a whole with the rotating base, which not only expands the working coverage of the robot, but also provides stable rotary support for the serial mechanical arm, avoids the aggravation of the error caused by the base shaking, and thus realizes the self-balancing of the internal force of the closed-loop structure of the robot, improves the rigidity of the end of the robot, reduces the cumulative error and resonance, improves the dynamic positioning accuracy, and thus meets the demand of high-rigidity machining applications.

Description

Technical Field

[0001] This invention relates to the field of robotics, and more specifically to a high-rigidity hybrid configuration robot. Background Technology

[0002] Traditional industrial robots have significant advantages in machining techniques such as grinding and drilling, which involve small or axial loads. However, in composite material processing or special machining, the large cutting forces, primarily radial loads, easily induce strong resonance between the workpiece and the robot. Therefore, the application of typical open-chain serial industrial robots in high-rigidity machining is severely limited. Improving robot rigidity is expected to fundamentally improve the stability and accuracy of robotic milling systems. Five-axis parallel mechanisms can effectively improve robot rigidity; however, their small workspace and poor flexibility cannot meet the machining requirements of large components. In contrast, hybrid robots based on a serial configuration and incorporating multiple closed-chain mechanisms can better balance heavy load, large workspace, high rigidity, and high precision, overcoming the shortcomings of traditional multi-axis parallel / joint serial configurations. Furthermore, redundant drives can actively counteract dynamic load deformation by adding drive units exceeding the number of degrees of freedom, constructing an internal force closed-loop system in the kinematic chain, thereby effectively improving robot rigidity and control bandwidth. However, due to the strong mechanical coupling effect between actuators, there are problems such as uneven load distribution, asynchronous movement, and excessive internal force of coupling branch constraint during the motion process.

[0003] The existing hybrid robots use two rotating pairs connected in series on the basis of a parallel mechanism to form a series chain, forming a hybrid structure with five degrees of freedom. This combines the advantages of the large workspace and flexible movement of the serial mechanism. However, its reliance on the parallel mechanism also results in a large space occupation. Some other hybrid robots use an integrated linear guide slide, combined with a three-axis industrial robotic arm module and a 2UPR-RPU parallel processing module, which combines the advantages of both serial and parallel structures. However, the rigidity is only improved in the end effector through the parallel module. The flexibility of the serial robotic arm is difficult to eliminate due to backlash, load deformation, etc., which causes resonance, increases cumulative error, and affects positioning accuracy. As a result, it is still difficult to meet the requirements of high-rigidity processing such as composite material processing or special processing. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a high-rigidity hybrid robot configuration. Based on a serial robotic arm, redundant actuator groups are introduced to form a hybrid robot. The multiple telescopic struts of the redundant actuator groups can actively counteract dynamic load deformation, thereby achieving self-balancing of internal forces in the robot's closed-loop structure, improving the robot's end-effector stiffness, reducing cumulative errors and resonance, and improving dynamic positioning accuracy, thus meeting the needs of high-rigidity machining applications.

[0005] To achieve the above objectives, the following solution is adopted:

[0006] A high-rigidity hybrid configuration robot, comprising:

[0007] A rotating base with a hinged support;

[0008] A series robotic arm includes a base, a two-axis link, and a three-axis link that are hinged in sequence. A joint motor is installed at the hinge position. The base is rotatably mounted on a rotating base. A first rotating shaft parallel to the hinge axis is provided between the two ends of the two-axis link. A second rotating shaft and a third rotating shaft arranged at intervals and parallel to the hinge axis are provided between the two ends of the three-axis link.

[0009] The redundant actuator group includes multiple telescopic struts. One end of the first telescopic strut is connected to a hinged support via a pin, and the other end is connected to one end of the third telescopic strut via a pin. The other end of the third telescopic strut is rotatably connected to a second rotating shaft, forming support for the serial robotic arm along the rotation direction of the base. The two ends of the second telescopic strut are rotatably connected to the hinged support and the first rotating shaft, respectively. The two ends of the fourth telescopic strut are rotatably connected to the first rotating shaft and the third rotating shaft, respectively.

[0010] Furthermore, a first sleeve and a second sleeve are fixed on the three-axis connecting rod. The first sleeve is closer to the two-axis connecting rod than the second sleeve. The second rotating shaft is located on the first sleeve, and the third rotating shaft is located on the second sleeve.

[0011] Furthermore, the three-axis connecting rod is provided with a second rotating shaft and a third rotating shaft on both sides, and is connected to a corresponding telescopic support rod.

[0012] Furthermore, both the first sleeve and the second sleeve include a first sleeve lobe and a second sleeve lobe that interlock, and the first sleeve lobe and the second sleeve lobe interlock to form a ring that is fixed on the three-axis connecting rod.

[0013] Furthermore, the two sides of the serial robotic arm are respectively connected to third telescopic support rods, and the two third telescopic support rods are hinged to the same first telescopic support rod by pins, and the position of the first telescopic support rod connecting pin is located between the two third telescopic support rods.

[0014] Furthermore, the two sides of the serial robotic arm are respectively connected to second telescopic support rods, and the first telescopic support rod is located between the two second telescopic support rods on both sides, and is hinged together to the hinge support.

[0015] Furthermore, the second and third rotating shafts are connected by a hinged connecting rod, with the second and third rotating shafts respectively fitted at both ends of the hinged connecting rod.

[0016] Furthermore, the telescopic support rod is an electric telescopic cylinder. The guide rod end of the first telescopic support rod is connected to the cylinder end of the third telescopic support rod via a pin. The guide rod end of the second telescopic support rod is connected to the hinge support via a pin. The guide rod end of the fourth telescopic support rod is connected to the third rotating shaft.

[0017] Furthermore, the rotating base is covered with a protective cover, and the hinged support is mounted on the protective cover.

[0018] Furthermore, the first execution group, consisting of the first telescopic support rod and the third telescopic support rod, is spaced apart from the second execution group, consisting of the second telescopic support rod and the fourth telescopic support rod, and the first execution group is located above the second execution group.

[0019] Compared with the prior art, the advantages and positive effects of this invention are:

[0020] To address the persistent issues of flexible deformation and cumulative errors in the main body of current serial robotic arms, and the problems of uneven load distribution and asynchronous movement in redundant actuators due to mechanical coupling, a new design is proposed. A rotating base serves as the core support carrier, with hinged supports mounted on it to provide fixed hinge points for the redundant actuator group. The redundant actuator group consists of four functionally complementary telescopic struts, forming multiple closed-chain supports. The first and third telescopic struts are connected in series, one end connected to the hinged support of the rotating base, and the other end connected to the second rotating shaft of the three-axis linkage, thus providing rigid support for the serial robotic arm along the rotation direction of the base. The second telescopic strut directly connects the hinged support to the second shaft. The first pivot of the connecting rod and the fourth telescopic support rod connect the first pivot of the two-axis connecting rod and the third pivot of the three-axis connecting rod. When the two-axis connecting rod is subjected to radial cutting force and has a tendency to bend or twist, the second telescopic support rod can provide reverse support force through its own axial stiffness to offset part of the load deformation. The fourth telescopic support rod, together with the third telescopic support rod, forms a two-way support for the three-axis connecting rod. When the three-axis connecting rod is subjected to axial or radial load, the two sets of support chains can decompose the load force into a component force along the axial direction of the telescopic support rod. The high axial stiffness of the support rod resists deformation. The four support rods together form a spatial closed chain covering the two-axis connecting rod and the three-axis connecting rod, realizing redundant drive and stiffness compensation.

[0021] The four telescopic struts form a closed spatial chain, constituting a statically indeterminate internal force system. When the robot is subjected to dynamic cutting loads, the output thrust of each telescopic strut can be adjusted in real time according to the load changes. When the two-axis connecting rod is subjected to an instantaneous impact and tends to shift to one side, the second telescopic strut can increase the thrust, and the fourth telescopic strut can adjust the tension in coordination. Through the internal force transmission of the closed chain system, the impact load is distributed to each strut and the rotating base, avoiding resonance caused by concentrated force on a single joint or connecting rod.

[0022] In a tandem robotic arm, the stiffness of each joint and link is progressively amplified, resulting in multi-level amplification of the end effector's motion deformation. The two-axis and three-axis links have the most significant impact on machining accuracy. A redundant actuator group, articulated with the two-axis and three-axis links of the tandem robotic arm, forms a closed-chain drive, effectively preventing the transmission of deformation from the robot's flexible components to the end effector. Furthermore, the hinge points of the redundant actuator group are all designed on the robotic arm's supporting structure, achieving full degree-of-freedom decoupling between the redundant actuator group and the tandem robotic arm. The maximum working length of each closed-chain electric cylinder meets the robot's large-aperture configuration envelope boundary, enhancing robot stiffness while meeting the demands of complex machining operations, demonstrating high adaptability and compatibility. Attached Figure Description

[0023] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0024] Figure 1 This is a schematic diagram of the assembly structure of the high-rigidity hybrid configuration robot in an embodiment of the present invention.

[0025] Figure 2 This is a top view schematic diagram of a high-rigidity hybrid configuration robot in an embodiment of the present invention.

[0026] Figure 3 This is a schematic diagram of the serial robotic arms in an embodiment of the present invention.

[0027] Figure 4 This is a schematic diagram of the sleeve structure in an embodiment of the present invention.

[0028] Figure 5 This is a schematic diagram of the redundant actuator group in an embodiment of the present invention.

[0029] Figure 6 This is a schematic diagram of the telescopic support rod in an embodiment of the present invention.

[0030] The components include: 1. Rotating base; 2. Hinge support; 3. First telescopic support rod; 4. Second telescopic support rod; 5. Third telescopic support rod; 6. Fourth telescopic support rod; 7. Base; 8. Two-axis connecting rod; 9. First rotating shaft; 10. First sleeve; 11. Three-axis connecting rod; 12. Second sleeve; 13. Hinge connecting rod; 14. First pin; 15. Second bolt; 16. Cotter pin; 17. Second pin; 18. Stop cover; 19. Third bolt; 20. Reference shaft. Line; 21. Robot center working surface; 101. Bottom fixing plate; 102. Gearbox; 103. First servo motor; 104. Protective cover; 301. Guide rod lug; 302. Linear guide rod; 303. Guide rod cylinder; 304. Second servo motor; 305. Fourth bolt; 306. Transmission box; 307. Cylinder lug; 1001. First sleeve flap; 1002. Second sleeve flap; 1003. Fifth bolt; 1004. Second rotating shaft. Detailed Implementation

[0031] In a typical embodiment of the present invention, such as Figure 1 - Figure 6 As shown, a high-rigidity hybrid configuration robot is presented.

[0032] In this embodiment, "axial direction" refers to the direction along the axis of the corresponding cylindrical structure, and "robot center working surface 21" refers to the plane determined by the axis of the two-axis link 8 and the axis of the three-axis link 11.

[0033] Existing robotic technologies have shortcomings in high-rigidity machining scenarios such as composite material processing and special machining. Traditional open-chain serial robotic arms lack sufficient rigidity and are prone to joint backlash deformation and link flexibility deformation under large radial cutting forces. They are also susceptible to resonance under dynamic loads, leading to loss of machining accuracy. Existing hybrid robots have limitations; some are based on parallel mechanisms, resulting in large space occupation, while others only improve rigidity at the end effector through parallel modules. The flexibility deformation and cumulative errors of the serial robotic arm body cannot be eliminated, and redundant actuators are prone to uneven load distribution and asynchronous movement due to mechanical coupling. Based on this, this embodiment provides a high-rigidity hybrid configuration robot. While ensuring a large workspace and flexibility, it reduces the flexibility deformation and cumulative errors of the serial robotic arm body through structural optimization, avoids resonance under dynamic loads, and solves the mechanical coupling problem of redundant actuators. It achieves self-balancing of internal forces in the closed-loop structure, improves the robot's end effector rigidity and dynamic positioning accuracy, and meets the requirements of high-rigidity machining.

[0034] like Figure 1 - Figure 6 As shown, the high-rigidity hybrid configuration robot mainly includes a rotating base 1, a series robotic arm, and a redundant actuator group.

[0035] With the rotating base 1 as the core support carrier, the hinge support 2 is installed on the base to provide a fixed hinge point for the redundant actuator group; the base 7 of the serial robotic arm is rotatably installed on the rotating base 1 and can rotate as a whole with the rotating base 1, which not only expands the robot's working range, but also provides stable rotation support for the serial robotic arm and avoids the base 7 shaking and aggravating the error.

[0036] The main body of the serial robotic arm adopts a sequentially hinged structure of base 7, two-axis link 8, and three-axis link 11. The end of the three-axis link 11 can connect to other axis link structures and end effector structures to form a multi-degree-of-freedom robotic arm, such as a five-degree-of-freedom robotic arm. Combined with base 7 and mounted on rotating base 1, it forms a six-degree-of-freedom robot. The five-degree-of-freedom robotic arm has five joints and five links, and the six-degree-of-freedom robot formed by the rotating base 1 can meet most processing and manufacturing needs. When the load borne by the end of the serial robotic arm is transmitted to the rotating base 1, the joint links are amplified due to the cantilever beam superposition effect and inertial load. In this embodiment, stiffness compensation is mainly performed on the two-axis link 8 and the three-axis link 11 of the five-degree-of-freedom serial robot.

[0037] In this embodiment, the bottom fixing plate 101 of the rotating base 1 is connected to the pre-embedded bolt holes in the ground by bolts, providing a rigid connection for the robot as a whole. The gearbox 102 is the core component of the rotating base 1. The first servo motor 103 is fixed to the gearbox 102 by bolts. Parallel shaft gear meshing converts the high-speed, low-torque rotation of the motor into low-speed, high-torque rotation. Power is transmitted from the output gear at the top of the gearbox 102 to the serial robotic arm, thereby providing the robot with the necessary power for its movement along the rotation path. Figure 1 The rotation angle along the reference axis 20 shown can be achieved by a planetary reducer, RV reducer, or spur gear transmission inside the gearbox 102; no specific limitation is made here. The protective cover 104 is bolted to the output gear of the gearbox 102, preventing damage from chips and impurities during machining as it rotates with the serial robotic arm. Two hinged supports 2, symmetrically distributed along the robot's central working surface 21, are arranged at the top of the protective cover 104 and fixed by bolts or welding; no specific limitation is made here. The hinged supports 2 provide the first hinge point for the multi-closed-chain redundant drive actuator group, providing support and fixation for the multi-closed-chain redundant drive actuator group.

[0038] The base 7 is equipped with a connecting base at the bottom, which is fixed to the output gear on the reduction gearbox 102 in the rotating base 1 by bolts. The rotating base 1 drives the serial robotic arm to rotate as a whole, thus forming a six-degree-of-freedom open-chain serial robot.

[0039] Joint motors are installed at the hinge positions of the tandem robotic arms. These motors provide rotational power to each link, ensuring the robot's flexibility and large workspace. Specifically, the two-axis link 8 has a first rotating shaft 9 parallel to its own hinge axis, and the three-axis link 11 has a second rotating shaft 1004 and a third rotating shaft spaced apart and parallel to its own hinge axis. These shafts provide connection hinge points for the redundant actuator group, reinforcing the two-axis link 8 and the three-axis link 11, which have the greatest impact on rigidity.

[0040] The redundant actuator group is a closed-chain support structure for the serial robotic arm. The redundant actuator group consists of four functionally complementary telescopic struts, forming multiple closed-chain supports. The four telescopic struts are designated as first telescopic strut 3, second telescopic strut 4, third telescopic strut 5, and fourth telescopic strut 6. First telescopic strut 3 and third telescopic strut 5 are connected in series. One end of first telescopic strut 3 is connected to the hinge support 2 of the rotating base 1, and the other end is connected to the second rotating shaft 1004 on the three-axis connecting rod 11 via third telescopic strut 5, thus providing rigid support for the serial robotic arm along the rotation direction of the base 7. Second telescopic strut 4 is directly connected to the hinge support 2 and the first rotating shaft 9 of the two-axis connecting rod 8. Fourth telescopic strut 6 connects the first rotating shaft 9 of the two-axis connecting rod 8 and the third rotating shaft of the three-axis connecting rod 11. The four struts together form a spatial closed chain covering the two-axis connecting rod 8 and the three-axis connecting rod 11, achieving redundant drive and stiffness compensation.

[0041] The two-axis connecting rod 8 and the base 7 are hinged together by a reducer, and the joint motor is driven by a servo motor to achieve mutual rotation between the two. The first rotating shaft 9 is fixed to both sides of the two-axis connecting rod 8 by bolts, or it can be fixed by welding, which is not specifically limited here. The first rotating shaft 9 can provide a second hinge point for the redundant actuator group, and the position of the two-axis connecting rod 8 can be precisely controlled by the second telescopic support rod 4 and the fourth telescopic support rod 6.

[0042] To enhance the stiffness of the biaxial link 8, the two ends of the second telescopic support rod 4 are respectively hinged to the hinged support 2 of the rotating base 1 and the first rotating shaft 9 of the biaxial link 8, forming an oblique support for the biaxial link 8. When the biaxial link 8 is subjected to radial cutting force and tends to bend, swing relative to the base 7, or twist, the second telescopic support rod 4 can provide a reverse support force through its own axial stiffness to offset part of the load deformation; at the same time, the fourth telescopic support rod 6 connects the biaxial link 8 and the triaxial link 11, forming a linkage support between the biaxial link 8 and the triaxial link 11, avoiding the deformation amplification caused by excessive force on the biaxial link 8 alone.

[0043] For stiffness enhancement of the three-axis connecting rod 11, a support chain formed by the first telescopic support rod 3 and the third telescopic support rod 5 connected in series is fixed at one end to the rotating base 1 and connected at the other end to the second rotating shaft 1004 of the three-axis connecting rod 11, providing rigid constraint for the three-axis connecting rod 11 in the rotation direction along the base 7; the fourth telescopic support rod 6 connects the third rotating shaft of the three-axis connecting rod 11 with the first rotating shaft 9 of the two-axis connecting rod 8, and together with the third telescopic support rod 5, forms bidirectional support for the three-axis connecting rod 11. When the three-axis connecting rod 11 is subjected to axial or radial load, the two sets of support chains can decompose the load force into a component force along the axial direction of the telescopic support rod, using the high axial stiffness of the support rod to resist deformation, and limiting the flexible deformation of the three-axis connecting rod 11 to a small range.

[0044] The first rotating axis 9 is fixed in a position such that when the robot moves to its limit position, the second telescopic support rod 4 and the fourth telescopic support rod 6, which are hinged to it, should be within their travel range and should not reduce the robot's movement space or interfere with other components of the robot. The two-axis link 8 and the three-axis link 11 are hinged via a reducer, and the joint motors are driven by servo motors to achieve mutual rotation between them. The second rotating axis 1004 and the third rotating axis provide the third and fourth hinge points for the redundant actuator group.

[0045] The four telescopic struts form a closed spatial chain, constituting a statically indeterminate internal force system. When the robot is subjected to dynamic cutting loads such as periodic impacts, the control system can adjust the output thrust of each telescopic strut in real time according to the load changes. For example, when the two-axis link 8 is subjected to an instantaneous impact and tends to shift to one side, the second telescopic strut 4 can increase the thrust, and the fourth telescopic strut 6 can adjust the tension in coordination. Through the internal force transmission of the closed chain system, the impact load is distributed to each strut and the rotating base 1, avoiding resonance caused by concentrated force on a single joint or link.

[0046] The multi-telescopic strut design of redundant actuator groups can reduce cumulative errors through error averaging. The backlash or geometric errors of the joints in the two-axis link 8 and the three-axis link 11 are compensated for by the minute displacements of each strut in the closed-chain system. For example, if the three-axis link 11 experiences a slight deflection due to joint backlash, the third telescopic strut 5 and the fourth telescopic strut 6 can correct the deflection by finely adjusting their lengths, achieving internal force self-balancing and preventing the error from propagating along the kinematic chain to the end effector.

[0047] The second telescopic support rod 4 directly supports the two-axis connecting rod 8. The first telescopic support rod 3 and the third telescopic support rod 5 mainly constrain the rotation direction of the three-axis connecting rod 11. The fourth telescopic support rod 6 realizes the linkage and coordination between the two-axis connecting rod 8 and the three-axis connecting rod 11, avoiding load conflicts caused by the overlapping functions of multiple supports. At the same time, the support rod layout adopts a symmetrical layout along the robot's central working surface 21, which can make the force on both sides uniform and reduce the problem of uneven load distribution of the actuator.

[0048] The telescopic support rod is connected to each component using pin hinges. Furthermore, the first pivot 9 of the two-axis link 8, and the second pivot 1004 and third pivot of the three-axis link 11 are all parallel to their respective hinge axes. This ensures that the telescopic support rod only transmits axial force and does not generate additional radial or torsional torque. This design decouples the motion of the telescopic support rod from the rotational degrees of freedom of the tandem robotic arm, avoiding excessive internal forces in the coupling chain due to asynchronous motion and ensuring coordinated action of each actuator.

[0049] The open-chain serial structure of base 7, two-axis link 8, and three-axis link 11, combined with the rotation function of rotating base 1, enables a wide range of work coverage, meeting the workspace requirements for processing large components. Joint motors drive the rotation of each link, ensuring the robot's flexibility in complex processing paths and avoiding the limited workspace limitations of parallel mechanisms. The maximum working length of each telescopic support can cover the maximum opening configuration of the serial robotic arm. For example, when two-axis link 8 and three-axis link 11 rotate to their limit angles, they provide rigidity support without restricting the normal range of motion of the robotic arm, achieving a balance between high rigidity and large space.

[0050] The closed-loop support of redundant actuator groups significantly improves the stiffness of the robot's end effector, reduces the flexibility and deformation of the robot joints under dynamic loads, effectively offsets and reduces cumulative joint errors, and improves dynamic positioning accuracy. This meets the high requirements for milling accuracy and drilling stability in composite material processing and special machining, avoiding abnormal tool wear or workpiece scrap. The statically indeterminate internal force closed-loop system can actively disperse dynamic impact loads. Combined with the real-time thrust adjustment of each telescopic support, it can effectively suppress high-frequency milling chatter, enabling the robot to maintain stable operation in high-speed, heavy-load machining scenarios and improving the surface quality of the machined parts. The structural design based on serial robotic arms retains the advantages of open-chain robots, such as large workspace and high flexibility. It can adapt to the multi-directional machining needs of large components, has a wider range of applications than five-axis parallel mechanisms, and occupies less space than existing hybrid robots.

[0051] like Figure 3 , Figure 4 As shown, a first sleeve 10 and a second sleeve 12 are fixed on the three-axis connecting rod 11. The first sleeve 10 is closer to the two-axis connecting rod 8 than the second sleeve 12. A second rotating shaft 1004 is provided on the first sleeve 10, and a third rotating shaft is provided on the second sleeve 12. The two sides of the three-axis connecting rod 11 are respectively provided with a second rotating shaft 1004 and a third rotating shaft, and are respectively connected to corresponding telescopic support rods. The first sleeve 10 and the second sleeve 12 both include a first sleeve lobe 1001 and a second sleeve lobe 1002 that are interlocked. The first sleeve lobe 1001 and the second sleeve lobe 1002 are interlocked into a ring and fixed on the three-axis connecting rod 11.

[0052] Specifically, the first sleeve 10 and the second sleeve 12 have the same structure, both consisting of a first sleeve lobe 1001 and a second sleeve lobe 1002, fixed to the three-axis connecting rod 11 to provide a hinge point for the telescopic support rod. The main body of the first sleeve lobe 1001 and the second sleeve lobe 1002 are both semi-circular rings, which, when assembled, form a circular ring. A stop groove is left on the inner side of the semi-circular ring. A corresponding stop is machined at a suitable position on the three-axis connecting rod 11. After installation, this prevents the sleeve from rotating along the axis of the three-axis connecting rod 11. A rotating shaft is machined on the outer side of the circular ring. After the sleeve is installed, it must be ensured that the axes of the rotating shafts of the first sleeve lobe 1001 and the second sleeve lobe 1002 are collinear and perpendicular to the robot's central working surface 21. A threaded hole is machined on the outer end face of the rotating shaft to fix the stop cover 18. Through holes and threaded holes are machined on both sides of the first sleeve segment 1001 and the second sleeve segment 1002 respectively. They are connected and fixed by cooperating with the fifth bolt 1003. After the fixing is completed, a gap should be left on the bolt connection surface of the first sleeve segment 1001 and the second sleeve segment 1002 to ensure that the sleeve does not slide along the axis of the three-axis connecting rod 11.

[0053] The first sleeve 10 and the second sleeve 12, through a petal-shaped interlocking structure, can be easily disassembled and stably fixed to the three-axis connecting rod 11, avoiding complex machining of the three-axis connecting rod 11 body. The second rotating shaft 1004 and the third rotating shaft, symmetrically distributed on both sides, together with the matching telescopic support rod, form a double-sided support structure, ensuring that the three-axis connecting rod 11 is subjected to uniform force and preventing deflection deformation caused by unilateral force. At the same time, the spaced arrangement of the first sleeve 10 and the second sleeve 12 provides a reasonable lever arm for the third telescopic support rod 5 (connected to the second rotating shaft 1004) and the fourth telescopic support rod 6 (connected to the third rotating shaft), ensuring that the two support rods can work together to decompose the radial and axial loads borne by the three-axis connecting rod 11, further enhancing the stiffness compensation effect.

[0054] like Figure 5 As shown, the tandem robotic arm has third telescopic support rods 5 connected to both sides. The third telescopic support rods 5 on both sides are hinged to the same first telescopic support rod 3 via pins, with the pins of the first telescopic support rod 3 positioned between the two third telescopic support rods 5. The tandem robotic arm also has second telescopic support rods 4 connected to both sides. The first telescopic support rod 3 is located between the two second telescopic support rods 4 and is hinged to a hinge support 2. Similarly, the second telescopic support rods 4 on both sides are symmetrically distributed, with the first telescopic support rod 3 located between the two second telescopic support rods 4 and hinged to the hinge support 2. This symmetrical layout ensures that the supporting force of the redundant actuator group on the tandem robotic arm is centrally symmetrically distributed, avoiding robotic arm deviation caused by excessive thrust on one side of the support rod, solving the problem of uneven actuator load distribution, and enhancing the robot's stability under dynamic loads.

[0055] The first actuator group, consisting of the first telescopic support rod 3 and the third telescopic support rod 5, and the second actuator group, consisting of the second telescopic support rod 4 and the fourth telescopic support rod 6, are spaced apart, with the first actuator group located above the second actuator group, forming a double-layer closed-chain support. The upper first actuator group mainly bears the load of the three-axis connecting rod 11 along the rotation direction of the base 7, while the lower second actuator group mainly constrains the bending and torsion of the two-axis connecting rod 8. The two actuator groups have clear functional divisions, reducing mechanical coupling during movement and avoiding asynchronous movement caused by spatial interference of the support rods. At the same time, the double-layer structure can cover a wider range of load transmission paths, further improving the overall rigidity.

[0056] like Figure 1 and Figure 2 As shown, the second rotating shaft 1004 and the third rotating shaft are connected by a hinged connecting rod 13, with mating rotating shafts fitted at both ends of the connecting rod. This structure enables the two rotating shafts on the three-axis connecting rod 11 to form a rigid linkage. When the third telescopic support rod 5 pushes the second rotating shaft 1004 or the fourth telescopic support rod 6 pulls the third rotating shaft, the hinged connecting rod 13 can transmit the force, ensuring that the two rotating shafts move synchronously, avoiding the torsional deformation of the three-axis connecting rod 11 due to local stress, and at the same time strengthening the synergistic constraint effect of the third telescopic support rod 5 and the fourth telescopic support rod 6 on the three-axis connecting rod 11.

[0057] Specifically, the cylinder lug 307 of the first telescopic support rod 3 and the guide rod lugs 301 of the two second telescopic support rods 4 symmetrically distributed along the robot's central working surface 21 are connected to the hinge support 2 via a first pin 14. The first telescopic support rod 3 is positioned at the center of the two second telescopic support rods 4, and the three electric cylinders are positioned at the center of the hinge support 2. After the first pin 14 is connected, it is fixed to the hinge support 2 by a second bolt 15 to prevent the first pin 14 from rotating along the hinge axis. A cotter pin 16 is installed in the pin hole at the bottom of the first pin 14 to prevent the first pin 14 from rotating. 4. Axial movement and detachment: After the electric cylinder and the hinge support 2 are connected in series, a fixed hinge point of the closed-chain multi-link mechanism is formed to resist the reaction torque output by the electric cylinder during operation; the guide rod lug 301 of the first telescopic support rod 3 and the cylinder lug 307 of the two third telescopic support rods 5 symmetrically distributed along the central working surface 21 of the robot are connected in series by the second pin 17. The second pin 17 provides the thrust output hinge point for the electric cylinder. In order to prevent the second pin 17 from axial movement and detachment, threaded holes are provided on both ends of the second pin 17, and the stop cover 18 is fixed by the third bolt 19. The cylinder lug 307 of the second telescopic support rod 4 and the cylinder lug 307 of the fourth telescopic support rod 6 are hinged to the support shaft on the robot's two-axis connecting rod 8. The connection sequence is the second telescopic support rod 4 and the fourth telescopic support rod 6. After the connection is completed, the support shaft provides the driving hinge point and the fixing hinge point for the second telescopic support rod 4 and the fourth telescopic support rod 6, respectively. The stop cover 18 is fixed to the end face of the support shaft by the third bolt 19 to prevent axial movement and detachment during the rotation of the electric cylinder. Two lugs are provided on the hinge connecting rod 13. The guide rod lug 301 of the third telescopic support rod 5 and the hinge connecting rod 13 are connected to the support shaft. The lug on rod 13 is hinged to a pre-set rotating shaft on the first sleeve 10. The guide lug 301 of the fourth telescopic support rod 6 and the other side lug on the hinged connecting rod 13 are hinged to a pre-set rotating shaft on the second sleeve 12. The series connection sequence is the hinged connecting rod 13, the third telescopic support rod 5 or the fourth telescopic support rod 6. After the series connection is completed, the closed chain of the multi-link mechanism can be realized. The rotating shafts of the two sleeves can provide driving hinge points for the third telescopic support rod 5 and the fourth telescopic support rod 6. The stop cover 18 is fixed on the end face of the rotating shaft by the third bolt 19 to prevent axial movement and falling off during the rotation of the electric cylinder.

[0058] The high-rigidity hybrid configuration robot structure has four hinge points. The first hinge point is a fixed hinge point; when the first telescopic link 3 and the second telescopic link 4 provide driving thrust, the resulting reaction force is borne by the first hinge point. The thrust output by the second telescopic link 4 can be transmitted to the robot's two-axis linkage 8 through the second hinge point, causing it to rotate axially along the two-axis rotary joint. The second hinge point can also serve as a fixed hinge point; when the fourth telescopic link 6 provides driving thrust, the resulting reaction force is borne by the second hinge point. The thrust output by the third telescopic link 5 and the fourth telescopic link 6... The thrust can be transmitted to the robot's three-axis link 11 through the resultant force formed by the third and fourth hinge points, causing it to rotate axially along the three-axis rotary joint. The second pin 17 can serve as the driving hinge point of the first telescopic support 3 and the fixed hinge point of the third telescopic support 5. The thrust output by the first telescopic support 3 can be transmitted to the third telescopic support 5 through the second pin 17. On the one hand, it can provide additional driving torque for the rotation of the three-axis link 11. On the other hand, it can change the direction of the thrust of the third telescopic support 5 according to the robot's processing requirements, thereby achieving dynamic control with stiffness compensation.

[0059] The telescopic support rods utilize electric telescopic cylinders. The guide rod end of the first telescopic support rod 3 is hinged to the cylinder end of the third telescopic support rod 5. The guide rod end of the second telescopic support rod 4 is fitted with a hinged support 2. The guide rod end of the fourth telescopic support rod 6 is connected to a third rotating shaft. The differentiated connection between the guide rod end and the cylinder end of the electric telescopic cylinder allows for adjustment of the telescopic direction according to the force requirements of the support rod. The second telescopic support rod 4 needs to provide push-pull force to the dual-axis connecting rod 8, and the hinged support 2 connected to the guide rod end ensures stable transmission of the thrust. The hinged connection between the guide rod end of the first telescopic support rod 3 and the third telescopic support rod 5 allows for flexible adaptation to changes in the angle of the third telescopic support rod 5, avoiding the concentration of internal forces caused by rigid connections.

[0060] The electric telescopic cylinder includes a linear guide rod 302, a guide rod cylinder body 303, a second servo motor 304, and a transmission box 306. The linear guide rod 302 and the guide rod cylinder body 303 form a linear motion element. A guide rod lug 301 is provided at the top of the linear guide rod 302, and a cylinder lug 307 is provided at the bottom of the guide rod cylinder body 303. The lugs cooperate with a pin to form a power transmission and support assembly. The second servo motor 304 is fixed to the transmission box 306 by a fourth bolt 305. The transmission box 306 contains a reducer and a synchronous pulley. The torque and angle output by the second servo motor 304 are converted into the thrust and linear displacement output by the linear guide rod 302 via the transmission box 306. The electric telescopic cylinder can be configured as a lead screw and nut, gear and rack, or other high-rigidity linear drive devices such as electro-hydraulic servo actuators; no specific limitation is made here.

[0061] The symmetrical telescopic struts and pivot structure, combined with the linkage constraint of the hinged link 13, allows the load borne by the two-axis link 8 and the three-axis link 11 to be evenly transferred to the rotating base 1 through the two-sided struts, avoiding unilateral deformation. The layered execution group design covers the key stress areas of the two-axis and three-axis links 11, forming an all-round closed-chain support. This transforms the cantilever beam stress of the open-chain serial robotic arm into the stress of a statically indeterminate truss, significantly reducing the deformation caused by joint backlash and link flexibility, and further suppressing resonance.

[0062] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high-rigidity hybrid configuration robot, characterized in that, include: A rotating base with a hinged support; A series robotic arm includes a base, a two-axis link, and a three-axis link that are hinged in sequence. A joint motor is installed at the hinge position. The base is rotatably mounted on a rotating base. A first rotating shaft parallel to the hinge axis is provided between the two ends of the two-axis link. A second rotating shaft and a third rotating shaft arranged at intervals and parallel to the hinge axis are provided between the two ends of the three-axis link. The redundant actuator group includes multiple telescopic struts. One end of the first telescopic strut is connected to a hinged support via a pin, and the other end is connected to one end of the third telescopic strut via a pin. The other end of the third telescopic strut is rotatably connected to a second rotating shaft, forming support for the serial robotic arm along the rotation direction of the base. The two ends of the second telescopic strut are rotatably connected to the hinged support and the first rotating shaft, respectively. The two ends of the fourth telescopic strut are rotatably connected to the first rotating shaft and the third rotating shaft, respectively. When the robot is subjected to dynamic cutting loads, the output thrust of each telescopic support rod is adjusted in real time according to the load changes. When the two-axis connecting rod is subjected to instantaneous impact and tends to shift to one side, the second telescopic support rod increases the thrust and the fourth telescopic support rod adjusts the tension in coordination. Through the internal force transmission of the closed chain system composed of each telescopic support rod, the impact load is distributed to each telescopic support rod and the rotating base, avoiding resonance caused by concentrated force on a single joint or connecting rod.

2. The high-rigidity hybrid configuration robot as described in claim 1, characterized in that, The three-axis connecting rod is fixed with a first sleeve and a second sleeve. The first sleeve is closer to the two-axis connecting rod than the second sleeve. The second rotating shaft is located on the first sleeve, and the third rotating shaft is located on the second sleeve.

3. The high-rigidity hybrid configuration robot as described in claim 2, characterized in that, The three-axis connecting rod has a second rotating shaft and a third rotating shaft on both sides of its axis, and each shaft is connected to a corresponding telescopic support rod.

4. The high-rigidity hybrid configuration robot as described in claim 2 or 3, characterized in that, The first sleeve and the second sleeve both include a first sleeve lobe and a second sleeve lobe that interlock, and the first sleeve lobe and the second sleeve lobe interlock to form a ring that is fixed on the three-axis connecting rod.

5. The high-rigidity hybrid configuration robot as described in claim 1, characterized in that, The two sides of the serial robotic arm are respectively connected to a third telescopic support rod. The third telescopic support rods on both sides are hinged to the same first telescopic support rod by a pin, and the position of the pin connecting the first telescopic support rod is located between the third telescopic support rods on both sides.

6. The high-rigidity hybrid configuration robot as described in claim 5, characterized in that, The two sides of the serial robotic arm are respectively connected to the second telescopic support rods, and the first telescopic support rod is located between the two second telescopic support rods on both sides and is hinged together to the hinge support.

7. The high-rigidity hybrid configuration robot as described in claim 1, characterized in that, The second and third rotating shafts are connected by a hinged connecting rod, with the second and third rotating shafts respectively fitted at both ends of the hinged connecting rod.

8. The high-rigidity hybrid configuration robot as described in claim 1, characterized in that, The telescopic support rod is an electric telescopic cylinder. The guide rod end of the first telescopic support rod is connected to the cylinder end of the third telescopic support rod via a pin. The guide rod end of the second telescopic support rod is connected to the hinge support via a pin. The guide rod end of the fourth telescopic support rod is connected to the third rotating shaft.

9. The high-rigidity hybrid configuration robot as described in claim 1, characterized in that, The rotating base is covered by a protective cover, and the hinged support is mounted on the protective cover.

10. The high-rigidity hybrid configuration robot as described in claim 1, characterized in that, The first execution group, consisting of the first telescopic support rod and the third telescopic support rod, is spaced apart from the second execution group, consisting of the second telescopic support rod and the fourth telescopic support rod, with the first execution group located above the second execution group.

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