Multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission and use method
The multi-degree-of-freedom spherical motor, with its integrated gear meshing transmission and reducer design, solves the problems of low torque transmission efficiency and difficulty in installing reducers, thereby increasing torque density and output torque, and simplifying the processing and assembly process.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- TIANJIN UNIV
- Filing Date
- 2026-03-11
- Publication Date
- 2026-05-01
AI Technical Summary
Existing multi-degree-of-freedom spherical motors have limited torque transmission efficiency, making it difficult to increase torque density and install speed reducers, resulting in low output torque in the deflection direction.
The multi-degree-of-freedom spherical motor mechanism adopts gear meshing transmission. Through the gear cooperation of the pitch motor and roll motor, the pitch and roll motion of the main output shaft is realized. The driving method of the yaw direction is changed to gear meshing transmission, combined with the integrated structure of the reducer and the rotary motor.
It significantly improves the output torque in the deflection direction and the torque density in the roll direction, simplifies the precision requirements for component fit, and enhances the feasibility of mass production and the long-term reliability of the motor.
Smart Images
Figure CN121966133A_ABST
Abstract
Description
Multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission and its application method Technical Field
[0001] This invention relates to a multi-degree-of-freedom motor structure, and more particularly to a multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission and its usage method. Background Technology
[0002] Currently, with the rapid development of high-end equipment manufacturing, robotics, aerospace, and defense industries, spherical motors capable of single-axis pitch, yaw, and roll multi-degree-of-freedom motion are becoming increasingly popular. Their advantages, such as fast dynamic response, high control precision, and good reliability in extreme environments, allow them to replace traditional combinations of single-degree-of-freedom motors and mechanical transmission mechanisms. Multi-degree-of-freedom spherical motors not only enrich the theoretical framework of the motor field but also drive technological upgrades across multiple industries and help high-end equipment overcome technological bottlenecks.
[0003] Existing multi-degree-of-freedom spherical motors can be divided into three main categories based on the degree of electromagnetic decoupling between the stator and rotor. The first category consists of multi-degree-of-freedom spherical motors where neither the stator nor rotor is electromagnetically decoupled. In this type of motor, both the stator and rotor are spherical or near-spherical. The advantage of this type of motor is its simple mechanical structure, but its electromagnetic relationships are complex, especially when the magnetic path is composed of an iron core. In this type of motor, the stator and rotor responsible for different degrees of freedom are not differentiated and are coupled together, resulting in complex motion control. To reduce the degree of coupling, this type of motor is often designed as a coreless structure, thus leading to low torque density. To improve torque density and reduce the mutual coupling of torque in multiple degrees of freedom, the second type of spherical motor decouples the stator, meaning that different stators are responsible for motion in different degrees of freedom. However, the rotor is still not completely decoupled; that is, the spatial arrangement of the rotor magnetic poles is still spherical or near-spherical, and the rotor magnetic poles responsible for different degrees of freedom are still coupled together without decoupling. To further improve torque density and completely eliminate the coupling between multiple degrees of freedom motions, the third type of spherical motor, building upon the stator decoupling of the second type of spherical motor, also completely decouples the rotor. The third type of spherical motor replaces the two orthogonal annular stators with two orthogonal annular electromagnetic structures, with a cylindrical electromagnetic mechanism fixed within each of the two orthogonal annular electromagnetic mechanisms. The two orthogonal annular electromagnetic structures provide pitch and yaw drive, while the cylindrical electromagnetic structure provides roll drive. These three electromagnetic mechanisms are integrated through mechanical design. The stator and rotor in different degrees of freedom directions are only responsible for the motion in their respective degrees of freedom, thus achieving complete decoupling of multiple degrees of freedom motions. The three electromagnetic structures are integrated through mechanical design to meet dynamic constraints, ultimately realizing the multi-degree-of-freedom motion of the main output shaft on the cylindrical body.
[0004] Although the third type of multi-degree-of-freedom spherical motor achieves complete decoupling of multi-degree-of-freedom motion, it is difficult to install a speed reducer because it achieves multi-degree-of-freedom motion through a single shaft. Therefore, the torque density in the deflection direction is still relatively low.
[0005] The technical problems existing in the prior art are as follows: 1. The existing spherical motor uses traditional electromagnetic drive between the stator and rotor, which has limited torque transmission efficiency and makes it difficult to improve torque density.
[0006] 2. Multi-degree-of-freedom spherical motors complete pitch and yaw movements through a single shaft, making it difficult to install a speed reducer on the shaft. The output torque in the yaw direction is relatively low. Summary of the Invention
[0007] This invention provides a multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission and its usage method to solve the technical problems existing in the prior art.
[0008] The technical solution adopted by this invention to solve the technical problems existing in the prior art is as follows: a multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission, including a motor base, one or more pitch motors, one or more roll motors, a columnar body with a main output shaft, and two arched support frames; the two arched support frames are stacked vertically, with connecting shafts fixed to the outer sides of both ends, and at least one inner side of each frame is fixed to the outer shell of the pitch motor and the roll motor, and both frames are rotatably connected to the motor base through connecting shafts; the axes of any two adjacent connecting shafts are perpendicular to each other, and the axes of the four connecting shafts are located in the same plane and intersect at a point, which is called the center point; The output shaft axis of the pitch motor is perpendicular to the axis of a connecting shaft, and the output shaft axis of the roll motor is parallel to the axis of the connecting shaft; both the pitch motor and roll motor output shafts are fixedly connected to gears; the cylindrical body is provided with at least two arc-shaped racks; the center of the central arc of each arc-shaped rack coincides with the center point; the planes determined by the central arcs and center points of two adjacent arc-shaped racks are perpendicular to each other, and the gear on the output shaft of the pitch motor meshes with one of the arc-shaped racks; the gear on the output shaft of the roll motor meshes with the other arc-shaped rack; the center of the arch of both arched support frames is open, and the main output shaft on the cylindrical body extends from the center opening of the arch of the two arched support frames.
[0009] Furthermore, each arched support frame includes an arched beam and two U-shaped support seats connected to both ends of the arched beam; each U-shaped support seat includes a base plate and two parallel support plates connected to the base plate; a pair of pitch motors or a pair of roll motors are respectively installed on the two parallel support plates of one U-shaped support seat, and the output shafts of the pair of pitch motors or the pair of roll motors are fixedly connected to the same gear; or, one support plate is equipped with a pitch motor or a roll motor, and the other support plate is equipped with a counterweight that matches the pitch motor or roll motor, and the output shaft of the pitch motor or roll motor is rotatably connected to the corresponding counterweight; the gear is centrally located between the two support plates and rotatably connected to the two support plates; the connecting shaft is centrally fixed to the base plate with its back to the support plates.
[0010] Furthermore, the arched beam is curved.
[0011] Furthermore, each arched beam includes two arched strips; the two ends of one arched strip are fixedly connected to a support plate on the same side of two U-shaped support seats arranged opposite each other; the two ends of the other arched strip are fixedly connected to another support plate on the same side of the two U-shaped support seats.
[0012] Furthermore, each arched beam includes an arched plate with a central opening; the two ends of the arched plate are fixedly connected to the base plates of two U-shaped support seats arranged opposite each other.
[0013] Furthermore, the columnar body is the main spindle motor, and the main output shaft on the columnar body is the output shaft of the main spindle motor.
[0014] Furthermore, the pitch motor, roll motor, and / or spindle motor are geared motors.
[0015] Furthermore, the motor base includes a hemispherical housing; four bearings are evenly distributed around the hemispherical housing; and four connecting shafts are fixedly connected to the inner rings of the four bearings.
[0016] Furthermore, the envelope of the arc-shaped rack is a sphere.
[0017] This invention also provides a method for using the aforementioned multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission. Two connecting shafts fixed to both ends of one of the arched support frames are referred to as connecting shaft A and connecting shaft B; two connecting shafts fixed to both ends of the other arched support frame are referred to as connecting shaft C and connecting shaft D; the axes of connecting shafts A and B are defined as the X-axis, and the axes of connecting shafts C and D as the Y-axis; a roll motor is mounted on the arched support frame fixed to connecting shafts A and B; a pitch motor is mounted on the arched support frame fixed to connecting shafts C and D; the roll motor rotates, and through the meshing of a gear on its output shaft with an arc-shaped rack on the cylindrical body, the main output shaft on the cylindrical body rotates around the X-axis, achieving roll motion; the pitch motor rotates, and through the meshing of a gear on its output shaft with an arc-shaped rack on the cylindrical body, the main output shaft on the cylindrical body rotates around the Y-axis, achieving pitch motion.
[0018] The advantages and positive effects of this invention are: 1. By changing the driving method in the deflection direction from electromagnetic drive to gear meshing transmission, the output torque in the deflection direction is greatly increased.
[0019] 2. By integrating the reducer and rotary motor into a single internal structure, the torque density in the roll direction is significantly improved. This achieves an increase in torque density across multiple degrees of freedom.
[0020] 3. This invention achieves pitch and roll motion of the main output shaft through the meshing of rack and pinion. The components are simple in structure and easy to assemble. This invention reduces the precision requirements of parts fitting, simplifies the processing and assembly process, and improves the feasibility of mass production and long-term operational reliability of the motor. Attached Figure Description
[0021] Figure 1 is a schematic diagram of a multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission according to the present invention.
[0022] Figure 2 is a schematic diagram of the structure of the arched support frame and the rolling motor of the present invention.
[0023] Figure 3 is a schematic diagram of the structure of a spindle motor housing with four arc-shaped racks evenly distributed circumferentially.
[0024] Figure 4 is a schematic diagram of a motor base structure according to the present invention.
[0025] Figure 5 is a schematic diagram of the output shaft movement of a spindle motor according to the present invention.
[0026] Figure 6 is a schematic diagram of the output shaft degree of freedom constraint of a spindle motor according to the present invention.
[0027] Figure 7 is a schematic diagram of the control principle of a multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission according to the present invention.
[0028] In the diagram: 1. Connecting shaft A; 2. Arched strip connecting the pitch motor; 3. Output shaft of the main spindle motor; 4. Arc-shaped rack; 5. Arched strip connecting the roll motor; 6. Connecting shaft C; 7. Enclosure plate of the motor base; 8. Roll motor; 9. Connecting shaft B; 10. Bearing; 11. Gear; 12. Counterweight; 13. Main spindle motor; 14. Support plate A of the U-shaped support base; 15. Base plate of the U-shaped support base; 16. Support arm of the motor base; 17. Connecting shaft D; 18. Support plate B of the U-shaped support base; 19. Pitch motor.
[0029] The plane normal vector of the output shaft of the main spindle motor when it deflects around the X-axis to its maximum angle. d is the plane normal vector of the output shaft of the main spindle motor when it deflects around the Y-axis to its maximum angle; d is the diameter of the inscribed circle at the top of the four arc-shaped racks. The angle between the normals of the two planes when the output shaft of the main spindle motor reaches its maximum deflection angle around both the X-axis and Y-axis; This refers to the axial width of the arc-shaped rack. Detailed Implementation
[0030] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.
[0031] In the description of this invention, the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and do not require the invention to be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention. The terms "connected" and "linked" used in this invention should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; a direct connection or an indirect connection through intermediate components; or an electrical connection or signal transmission. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.
[0032] Please refer to Figures 1 to 7. A multi-degree-of-freedom spherical motor mechanism based on gear 11 meshing transmission includes a motor base, one or more pitch motors 19, one or more roll motors 8, a columnar body with a main output shaft, and two arched support frames. The two arched support frames are stacked vertically, with connecting shafts fixed to the outer sides of both ends. At least one inner side of each support frame is fixed to the housing of the pitch motor 19 and the roll motor 8, and both are rotatably connected to the motor base via connecting shafts. The axes of any two adjacent connecting shafts are perpendicular to each other, and the axes of the four connecting shafts are located in the same plane and intersect at a point, which is called the center point. The output shaft axis of the pitch motor 19 is connected to a connecting shaft. The axis of the column is perpendicular, and the output shaft axis of the roll motor 8 is parallel to the axis of the connecting shaft; the output shafts of the pitch motor 19 and the roll motor 8 are both fixedly connected to gears 11, and the column is provided with at least two arc-shaped racks 4; the center of the arc of each arc-shaped rack 4 coincides with the center point; the planes determined by the arcs of two adjacent arc-shaped racks 4 and the center point are perpendicular to each other, and the output shaft gear 11 of the pitch motor 19 meshes with one of the arc-shaped racks 4; the output shaft gear 11 of the roll motor 8 meshes with the other arc-shaped rack 4; the center of the arch of the two arched support frames is open, and the main output shaft on the column extends from the center opening of the arch of the two arched support frames.
[0033] In Figure 1, the two connecting shafts fixed to both ends of one of the arched support frames are called connecting shafts A1 and B9; the two connecting shafts fixed to both ends of the other arched support frame are called connecting shafts C6 and D17. Connecting shafts A1, C6, B9, and D17 are adjacent to each other, and their axes lie in the same plane. Connecting shafts A1 and C6 are perpendicular to each other; connecting shafts C6 and B9 are perpendicular to each other; connecting shafts B9 and D17 are perpendicular to each other; and connecting shafts D17 and A1 are perpendicular to each other.
[0034] The axes of connecting shafts A1 and B9 coincide, as do the axes of connecting shafts C6 and D17; the axes of the four connecting shafts intersect perpendicularly at a single point, which is called the center point; the output shaft axis of pitch motor 19 is perpendicular to the axis of connecting shaft A1; the output shaft axis of roll motor 8 is perpendicular to the axis of connecting shaft C6. The output shaft axis of roll motor 8 is parallel to the axis of connecting shaft A1.
[0035] The chord on the arc-shaped rack 4 is parallel to or at an angle of less than 90° to the axis of the main output shaft on the cylindrical body.
[0036] Preferably, each arc-shaped support frame may include an arc-shaped beam and two U-shaped support seats connected to both ends of the arc-shaped beam; each U-shaped support seat may include a base plate and two parallel support plates connected to the base plate.
[0037] A pair of pitch motors 19 or a pair of roll motors 8 are respectively mounted on the two parallel support plates of a U-shaped support base, and the output shafts of the pair of pitch motors 19 or the pair of roll motors 8 are fixedly connected to the same gear; or, one of the two parallel support plates of a U-shaped support base is equipped with a pitch motor 19 or a roll motor 8, and the other support plate is equipped with a counterweight 12 that matches the pitch motor 19 or the roll motor 8, and the output shaft of the pitch motor 19 or the roll motor 8 is rotatably connected to the corresponding counterweight 12.
[0038] Gear 11 is centrally located between the two support plates and is rotatably connected to the two support plates; the connecting shaft is centrally fixed to the base plate with its back to the support plates.
[0039] A U-shaped support can be equipped with a pair of pitch motors 19 or a pair of roll motors 8. In the two parallel support plates of a U-shaped support, each support plate is fixed with a pitch motor 19 or a roll motor 8.
[0040] Alternatively, a pitch motor 19 or a roll motor 8 can be installed on one of the two parallel support plates of a U-shaped support base. When a pitch motor 19 is installed, a counterweight 12 matching the pitch motor 19 is installed on the other support plate. The output shaft of the pitch motor 19 is rotatably connected to the counterweight 12 installed on the same U-shaped support base via bearings. When a roll motor 8 is installed, a counterweight 12 matching the roll motor 8 is installed on the other support plate. The output shaft of the roll motor 8 is rotatably connected to the counterweight 12 installed on the same U-shaped support base via bearings.
[0041] One arc-shaped support frame can be used to fix the housings of one or more pitch motors 19 at both ends via U-shaped support seats; another arc-shaped support frame can be used to fix the housings of one or more roll motors 8 at both ends via U-shaped support seats; the cross-section of the counterweight 12 can be polygonal or circular.
[0042] Preferably, the arched beam can be curved.
[0043] Preferably, each arched beam may include two arched strips; the two ends of one arched strip are fixedly connected to a support plate on the same side of two U-shaped support seats arranged opposite each other; the two ends of the other arched strip are fixedly connected to another support plate on the same side of the two U-shaped support seats.
[0044] Preferably, each arched beam may include an arched plate with a central opening; the two ends of the arched plate are fixedly connected to the base plates 15 of two U-shaped support seats arranged opposite each other.
[0045] Preferably, the columnar body can be the main spindle motor 13, and the main output shaft on the columnar body is the output shaft 3 of the main spindle motor.
[0046] Preferably, the pitch motor 19, the roll motor 8 and / or the spindle motor 13 can be geared motors.
[0047] Preferably, the motor base may include a hemispherical housing; four bearings 10 are evenly distributed around the hemispherical housing; and four connecting shafts are fixedly connected to the inner rings of the four bearings 10.
[0048] Preferably, the envelope surface of the arc-shaped rack 4 can be a sphere.
[0049] The present invention also provides a method for using the above-mentioned multi-degree-of-freedom spherical motor mechanism based on gear 11 meshing transmission. Two connecting shafts fixed to both ends of one of the arched support frames are referred to as connecting shaft A1 and connecting shaft B9; two connecting shafts fixed to both ends of the other arched support frame are referred to as connecting shaft C6 and connecting shaft D17; the axes of connecting shaft A1 and connecting shaft B9 are defined as the X-axis, and the axes of connecting shaft C6 and connecting shaft D17 as the Y-axis; the roll motor 8 is correspondingly mounted on the arched support frame fixed to connecting shaft A1 and connecting shaft B9; the pitch motor 19 is correspondingly mounted on the arched support frame fixed to connecting shaft C6 and connecting shaft D17. The roll motor 8 is rotated, and the gear 11 on its output shaft meshes with the arc-shaped rack 4 on the cylindrical body, thereby causing the main output shaft on the cylindrical body to rotate around the X-axis, thus achieving roll motion; the pitch motor 19 is rotated, and the gear 11 on its output shaft meshes with the arc-shaped rack 4 on the cylindrical body, thereby causing the main output shaft on the cylindrical body to rotate around the Y-axis, thus achieving pitch motion.
[0050] The structure and working principle of the present invention will be further described below with reference to a preferred embodiment: A multi-degree-of-freedom spherical motor structure based on gear 11 meshing transmission includes a motor base, two pairs of pitch motors 19, two pairs of roll motors 8, a main shaft motor 13, and two arched support frames; the two arched support frames are stacked vertically, with connecting shafts fixed to the outer sides of both ends, and the inner sides of both ends are fixed to the housings of the two pairs of pitch motors 19 and the two pairs of roll motors 8, respectively. The two support frames are rotatably connected to the motor base through connecting shafts; the two connecting shafts fixed to the two ends of one of the arched support frames are called connecting shaft A1 and connecting shaft B9; the two connecting shafts fixed to the two ends of the other arched support frame are called connecting shaft C6 and connecting shaft D17; the axes of connecting shaft A1 and connecting shaft B9 coincide, and the axes of connecting shaft C6 and connecting shaft D17 coincide. The axes of the four connecting shafts are located in the same plane and intersect at a point, which is called the center point; the output shaft axes of the two pairs of pitch motors 19 are parallel and perpendicular to the axis of connecting shaft A1; the output shaft axes of the two pairs of roll motors 8 are parallel and perpendicular to the axis of connecting shaft C6; the output shafts of the two pairs of pitch motors 19 and the two pairs of roll motors 8 are all fixedly connected to gears 11; the housing of the main spindle motor 13 has four arc-shaped racks 4 evenly distributed circumferentially; the center of the arc of the four arc-shaped racks 4 coincides with the center point; two opposite arc-shaped racks 4 form a pair, and the output shaft gears 11 of the two pairs of pitch motors 19 mesh with one pair of arc-shaped racks 4; the output shaft gears 11 of the two pairs of roll motors 8 mesh with the other pair of arc-shaped racks 4; the center of the arch of the two arched support frames is open, and the output shaft 3 of the main spindle motor extends from the center opening of the arch of the two arched support frames.
[0051] Each arched support frame may include an arched beam and two U-shaped support seats connected to both ends of the arched beam; each U-shaped support seat may include a base plate and two parallel support plates connected to the base plate; a pair of pitch motors 19 or a pair of roll motors 8 are respectively mounted on the two parallel support plates of a U-shaped support seat, and the output shafts of the pair of pitch motors 19 or the pair of roll motors 8 are fixedly connected to the same gear. The gear 11 is centrally located between the two support plates and is rotatably connected to the two support plates; the connecting shaft is centrally fixed to the base plate with its back to the support plates.
[0052] A pair of pitch motors 19 or a pair of roll motors 8 are installed on a U-shaped support base. That is, in the two parallel support plates of a U-shaped support base, each support plate is fixed with a pitch motor 19 or a roll motor 8.
[0053] Two U-shaped support bases are used to install two pairs of pitch motors 19 or two pairs of roll motors 8. The housings of four pitch motors 19 are fixed at both ends of one arched support frame through the U-shaped support bases; the housings of four roll motors 8 can be fixed at both ends of the other arched support frame through the U-shaped support bases.
[0054] The pitch motor 19, roll motor 8, and spindle motor 13 are all geared motors. The arched beam is curved.
[0055] Each arched beam includes two arched strips; the two ends of one arched strip are fixedly connected to a support plate on the same side of two U-shaped support seats arranged opposite each other; the two ends of the other arched strip are fixedly connected to another support plate on the same side of the two U-shaped support seats.
[0056] The multi-degree-of-freedom spherical motor mechanism based on gear 11 meshing transmission of the present invention can be composed of three electromagnetically decoupled mechanisms, or it can be designed as a two-degree-of-freedom structure. When the output shaft of the column does not rotate around the axis of the column, the multi-degree-of-freedom spherical motor mechanism is a two-degree-of-freedom structure. When the output shaft of the column rotates around the axis of the column, that is, when the column uses a rotary motor, more degrees of freedom of rotational motion can be achieved.
[0057] Referring to Figure 1, let the axes of connecting shaft A1 and connecting shaft B9 be the X-axis, and the axes of connecting shaft C6 and connecting shaft D17 be the Y-axis; two pairs of roll motors 8 are correspondingly mounted on the arched support frame fixed to connecting shaft A1 and connecting shaft B9; two pairs of pitch motors 19 are correspondingly mounted on the arched support frame fixed to connecting shaft C6 and connecting shaft D17; the two pairs of roll motors 8 rotate synchronously, thereby causing the output shaft on the cylindrical body to rotate around the X-axis, realizing roll motion; the two pitch motors 19 rotate synchronously, thereby causing the output shaft on the cylindrical body to rotate around the Y-axis, realizing pitch motion.
[0058] The pitch and roll motion of the output shaft 3 of the main spindle motor is achieved through the meshing of the rack and pinion gear 11. The integrated design of the reducer and rotary motor increases the output torque in the roll direction. This structure increases the output torque in multiple degrees of freedom, significantly improving the torque density of the entire motor. The multi-degree-of-freedom spherical motor mechanism based on gear 11 meshing transmission of this invention can be integrated with the reducer, overcoming the limitation of existing heavy spherical motors that are difficult to install reducers on, thus broadening the application range of this type of motor.
[0059] Two pairs of pitch motors 19 are connected together by an arched bar 2 that connects the pitch motors. The two pairs of pitch motors 19 are then rotatably connected to the motor base via connecting shaft C6 and connecting shaft D17. Two pairs of roll motors 8 are connected together by an arched bar 5 that connects the roll motors. The two pairs of roll motors 8 are then rotatably connected to the motor base via connecting shaft A1 and connecting shaft B9.
[0060] This structure allows the two pairs of pitch motors 19 to rotate synchronously around the Y-axis, and the arched bar structure has a relatively large supporting force that can withstand a large load.
[0061] The motor base includes a hemispherical shell; four bearings 10 are evenly distributed around the hemispherical shell; and four connecting shafts are fixedly connected to the inner rings of the four bearings 10.
[0062] The motor base includes a cylindrical base and four support arms. The four support arms 16 are evenly distributed circumferentially along the axis of the cylindrical base. Each support arm 16 includes an upper section and a lower section, with the upper and lower sections forming an angle of 100° to 130°. The upper section is parallel to the axis of the cylindrical base, and the lower section is fixedly connected to the bottom of the cylindrical base. The upper section has a bearing hole, and a bearing 10 is installed in the bearing hole. The four connecting shafts are fixedly connected to the inner rings of the bearings 10 on the support arms 16 of the four motor bases.
[0063] The outer side of the upper section of the support arm 16 of the four motor bases is fixed to the surrounding plate 7 of the motor base, thereby strengthening the support strength of the support arm 16 of the motor base.
[0064] To increase the lateral torque of the output shaft and reduce lateral wear on the connecting shaft by balancing the rotation of the arched support frame, the weights at both ends of the gear 11 are made equal, so the counterweight 12 has the same weight as the motor.
[0065] A U-shaped support base has two support plates, designated as support plate A14 and support plate B18. A pitch motor 19 or a roll motor 8 is connected to support plate A14. A counterweight block 12, which counterweights the pitch motor 19 or roll motor 8, is fixedly connected to support plate B18. A gear 11 is located between support plates A14 and B18. The base plate 15 of the U-shaped support base is fixedly connected to a connecting shaft. The connecting shaft is rotatably connected to the support arm 16 of the motor base via a bearing 10. An angle encoder can be installed to detect the rotation angle of the connecting shaft.
[0066] The present invention also provides a method for using the above-mentioned multi-degree-of-freedom spherical motor mechanism based on gear 11 meshing transmission. Let the axes of connecting shaft A1 and connecting shaft B9 be the X-axis, and the axes of connecting shaft C6 and connecting shaft D17 be the Y-axis. Two pairs of roll motors 8 are correspondingly mounted on arched support frames fixed to connecting shaft A1 and connecting shaft B9; two pairs of pitch motors 19 are correspondingly mounted on arched support frames fixed to connecting shaft C6 and connecting shaft D17. The two pairs of roll motors 8 rotate synchronously, thereby causing the output shaft 3 of the main spindle motor to rotate around the X-axis, achieving roll motion; the two pairs of pitch motors 19 rotate synchronously, thereby causing the output shaft 3 of the main spindle motor to rotate around the Y-axis, achieving pitch motion.
[0067] When the motor output shaft does not deflect, the two arched support frames are orthogonal to each other. When the arched support frames need to deflect, only the pitch motor 19 or roll motor 8 connected to the arched support frames needs to be controlled to rotate. The position of the output shaft 3 of the main spindle motor can be determined by detecting the deflection angle of the arched support frames. When controlling the pitch motor 19 or roll motor 8 to deflect, it is necessary to control the rotation of both pairs of pitch motors 19 and both pairs of roll motors 8 simultaneously and ensure that the speeds of the two pairs of pitch motors 19 or the two pairs of roll motors 8 are equal, thereby causing the arched support frames to deflect. During the deflection process, the rotation direction of the output shaft 3 of the main spindle motor is unaffected and can continue to rotate, thus completing multi-degree-of-freedom motion with a limited swing angle in any direction. When modified into a two-degree-of-freedom structure, the main spindle motor 13 is replaced with a cylindrical body, and the main output shaft on the cylindrical body does not rotate relative to the cylindrical body.
[0068] Referring to Figure 6, the deflection range of a multi-degree-of-freedom spherical motor mechanism based on gear 11 meshing transmission is limited, meaning it can only complete deflection motion with a finite swing angle. According to mechanical principles, when the output shaft 3 of the main spindle motor deflects to its maximum angle, it will interfere with the motor's structural components. The axial width constraint relationship of the arc-shaped rack is as follows: (1); (2); 0, -sin (3); (4); where: The plane normal vector of the output shaft of the main spindle motor when it deflects around the X-axis to its maximum angle. d is the plane normal vector of the output shaft of the main spindle motor when it deflects around the Y-axis to its maximum angle; d is the diameter of the inscribed circle at the top of the four arc-shaped racks. The angle between the normals of the two planes when the output shaft of the main spindle motor reaches its maximum deflection angle around both the X-axis and Y-axis; This represents the maximum roll or yaw angle. This refers to the axial width of the arc-shaped rack.
[0069] Therefore, the deflection angles of the main spindle motor 13 around the X and Y axes and the axial width of the arc rack 4 are mutually restrictive. An excessively large axial width of the arc rack 4 will compress the axial space of the pitch motor 19 and roll motor 8. Thus, the output torque in the deflection direction and the deflection range are mutually restrictive, and both should be considered comprehensively during design. The mechanical meshing drive deflection structure itself has a speed-reducing and torque-increasing effect, and each arc rack 4 is driven by one or two drive motors, resulting in a relatively large deflection torque. Therefore, the axial width of the arc rack 4 can be appropriately reduced to increase the maximum deflection range. Increasing the number of pitch motors 19 and roll motors 8 will increase the output torque.
[0070] During yaw motion, it is necessary to control the operation of the corresponding pitch motor 19 and roll motor 8, so that a pair of pitch motors 19 or a pair of roll motors 8 rotate synchronously, driving gear 11 to mesh with the arc-shaped rack 4, causing the arc-shaped rack 4 to deflect. As can be seen from the structural relationship, a pair of pitch motors 19 and a pair of roll motors jointly drive the arc-shaped rack 4 to deflect at the same speed and direction. Therefore, the motor speeds must be the same to ensure maximum output torque. Thus, coordinated control of the motor speeds is required. Given the requirement for high-precision coordinated control of multiple motor speeds, a strategy of cross-coupling coordinated control of speeds can be adopted. Referring to Figure 7, multiple motors share the same speed reference input signal and have their own independent speed signal feedback. Furthermore, the speed difference feedback signal of a pair of pitch motors 19 or a pair of roll motors 8 is multiplied by different gains and fed back to the input to regulate the corresponding motor speed. This control method can both ensure that each motor tracks the reference speed and efficiently reduce the speed difference between a pair of pitch motors 19 or a pair of roll motors 8 to achieve coordinated speed control.
[0071] The aforementioned connecting shaft, arched strip, arc rack 4, motor base enclosure 7, rolling motor 8, bearing 10, gear 11, counterweight 12, main shaft motor 13, U-shaped support seat, motor base support arm 16, pitch motor 19 and other components, structures and devices can all adopt applicable components, structures and devices in the prior art, or adopt components, structures and devices in the prior art and construct them using conventional technical means.
[0072] The embodiments described above are only used to illustrate the technical ideas and features of the present invention. Their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. The patent scope of the present invention should not be limited by these embodiments. That is, any equivalent changes or modifications made in accordance with the spirit disclosed in the present invention still fall within the patent scope of the present invention.
Claims
1. A multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission, characterized in that, The system includes a motor base, one or more pitch motors, one or more roll motors, a cylindrical body with a main output shaft, and two arched support frames. The two arched support frames are stacked vertically, with connecting shafts fixed to their outer ends. At least one inner end of each frame is fixed to the housing of the pitch and roll motors. Both frames are rotatably connected to the motor base via connecting shafts. The axes of any two adjacent connecting shafts are perpendicular to each other, and the axes of all four connecting shafts lie in the same plane and intersect at a single point, referred to as the center point. The output shaft axis of the pitch motor is perpendicular to the axis of one connecting shaft, and the output shaft axis of the roll motor is perpendicular to the axis of the connecting shaft. The axis of the shaft is parallel to the axis of the connecting shaft; the output shafts of the pitch motor and the roll motor are both fixedly connected to gears; the columnar body is provided with at least two arc-shaped racks; the center of the central arc of each arc-shaped rack coincides with the center point; the planes determined by the central arcs and center points of two adjacent arc-shaped racks are perpendicular to each other, and the gear on the output shaft of the pitch motor meshes with one of the arc-shaped racks; the gear on the output shaft of the roll motor meshes with the other arc-shaped rack; the center of the arch of the two arched support frames is open, and the main output shaft on the columnar body extends from the center opening of the arch of the two arched support frames.
2. The multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission according to claim 1, characterized in that, Each arched support frame includes an arched beam and two U-shaped support seats connected to both ends of the arched beam; each U-shaped support seat includes a base plate and two parallel support plates connected to the base plate; a pair of pitch motors or a pair of roll motors are respectively installed on the two parallel support plates of one U-shaped support seat, and the output shafts of the pair of pitch motors or the pair of roll motors are fixedly connected to the same gear; or, one support plate is equipped with a pitch motor or a roll motor, and the other support plate is equipped with a counterweight that matches the pitch motor or roll motor, and the output shaft of the pitch motor or roll motor is rotatably connected to the corresponding counterweight; the gear is centrally located between the two support plates and rotatably connected to the two support plates; the connecting shaft is centrally fixed to the base plate with its back to the support plates.
3. The multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission according to claim 2, characterized in that, The arched beam is curved.
4. The multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission according to claim 2, characterized in that, Each arched beam includes two arched strips; the two ends of one arched strip are fixedly connected to a support plate on the same side of two U-shaped support seats arranged opposite each other; the two ends of the other arched strip are fixedly connected to another support plate on the same side of the two U-shaped support seats.
5. The multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission according to claim 2, characterized in that, Each arched beam includes an arched slab with a central opening; the two ends of the arched slab are fixedly connected to the base plates of two U-shaped support seats arranged opposite each other.
6. The multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission according to claim 1, characterized in that, The cylindrical body is the main spindle motor, and the main output shaft on the cylindrical body is the output shaft of the main spindle motor.
7. The multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission according to claim 6, characterized in that, The pitch motor, roll motor, and / or spindle motor are geared motors.
8. The multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission according to claim 1, characterized in that, The motor base includes a hemispherical shell; four bearings are evenly distributed around the hemispherical shell; and four connecting shafts are fixedly connected to the inner rings of the four bearings.
9. The multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission according to claim 1, characterized in that, The envelope of the curved rack is a sphere.
10. A method of using a multi-degree-of-freedom spherical motor mechanism based on gear meshing transmission as described in any one of claims 1 to 9, characterized in that, Two connecting shafts fixed to both ends of one of the arched support frames are called connecting shaft A and connecting shaft B; two connecting shafts fixed to both ends of the other arched support frame are called connecting shaft C and connecting shaft D; let the axis of connecting shaft A and B be the X-axis, and the axis of connecting shaft C and D be the Y-axis; the roll motor is installed on the arched support frame fixed to connecting shaft A and B; the pitch motor is installed on the arched support frame fixed to connecting shaft C and D; the roll motor rotates, and through the gear on its output shaft meshing with the arc-shaped rack on the cylindrical body, the main output shaft on the cylindrical body rotates around the X-axis, thus achieving roll motion; the pitch motor rotates, and through the gear on its output shaft meshing with the arc-shaped rack on the cylindrical body, the main output shaft on the cylindrical body rotates around the Y-axis, thus achieving pitch motion.