Motion mechanisms and robots with them
By designing a combination of a moving platform and a multi-link mechanism, a simple fitting of spherical motion was achieved, solving the problem of complex fitting in existing technologies, simplifying the kinematics and control process, and reducing the difficulty of processing and installation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZHUHAI GREE INTELLIGENT EQUIP CO LTD
- Filing Date
- 2024-12-11
- Publication Date
- 2026-07-17
Smart Images
Figure CN119458287B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of mechanical mechanism technology, and more specifically, to a motion mechanism and a robot having the same. Background Technology
[0002] Currently, devices with simple structures and spherical translation output functions are being used more and more widely in fields such as rehabilitation training machines and camera positioning systems, and correspondingly, their demand is also increasing.
[0003] In the existing technology, the parallel mechanism that can realize the translation output of the spherical surface is usually a three-plane parallel translation mechanism. Its single-plane translation form is a straight movement. When the moving platform needs to translate along a curved trajectory, the processing module needs to linearly fit the straight movements in different directions to finally obtain the translation movement of an approximate curved trajectory.
[0004] However, the above fitting process is extremely complex. Each drive pair requires a complex control algorithm to control its own motion trajectory. The actual fitting process is prone to errors, and the motion trajectory of the moving platform is often not a perfect sphere. Summary of the Invention
[0005] The main objective of this invention is to provide a motion mechanism and a robot having it, so as to solve the problem that the fitting process of the three-translation parallel mechanism in the prior art is too complicated when outputting spherical motion.
[0006] To achieve the above objectives, according to one aspect of the present invention, a motion mechanism is provided, comprising: a moving platform; a stationary platform; and a first branch assembly including at least two first translational motion output mechanisms, a first parallelogram linkage mechanism, a second parallelogram linkage mechanism, and a first link, wherein the first translational motion output mechanisms are disposed on the stationary platform; the first parallelogram linkage mechanism has a plurality of second links, which are respectively a left second link, a right second link, an upper second link, and a lower second link, wherein the upper second link of the first parallelogram linkage mechanism is a transition link, and the transition link has a first connecting end located between its two ends, the first connecting end being used to connect with the right second link. The two links are rotatably connected so that one end of the transition link forms a second connection end; the transition link located between the second connection end and the first connection end is fixedly connected to the second parallelogram linkage mechanism, and the moving platform is fixedly connected to the second parallelogram linkage mechanism; at least one first translational motion output mechanism is fixedly connected to the lower second link, and at least another first translational motion output mechanism is rotatably connected to the second connection end through the first link; the second branch assembly includes a second translational motion output mechanism and a fourth link, the second translational motion output mechanism is rotatably connected to the moving platform through the fourth link, and the moving platform moves along the spherical surface under the joint drive of the first translational motion output mechanism and the second translational motion output mechanism.
[0007] Furthermore, the first translational motion output mechanism is slidably mounted on the stationary platform, and the motion trajectories of at least two first translational motion output mechanisms are collinear.
[0008] Furthermore, the first translational motion output mechanism is a parallelogram mechanism, which includes four fifth links that are rotatably connected to each other. One fifth link is set on a stationary platform, and the fifth link opposite to the fifth link is an output link for outputting translational motion. The motion trajectories of at least two output links of the first translational motion output mechanism are collinear.
[0009] Furthermore, the first translational motion output mechanism has a translational motion output direction S1, and the second translational motion output mechanism has a translational motion output direction S2, with the translational motion output direction S1 being perpendicular to the translational motion output direction S2.
[0010] Furthermore, the second translational motion output mechanism is slidably mounted on the stationary platform, and there are at least three fourth links. The end of the fourth link used to connect with the second translational motion output mechanism is fixed to the second translational motion output mechanism; or, the second translational motion output mechanism is rotatably and slidably mounted on the stationary platform, and there are at least two fourth links. The end of the fourth link used to connect with the second translational motion output mechanism is fixed to the second translational motion output mechanism, and the rotation axis of the second translational motion output mechanism is coaxial with the translational motion output direction S2 of the second translational motion output mechanism.
[0011] Furthermore, the plane in which the first parallelogram linkage mechanism is located is the first plane, and the plane in which the second parallelogram linkage mechanism is located is the second plane; wherein, during the movement of the moving platform, the first plane and the second plane are set perpendicular to each other.
[0012] Furthermore, the first link and the first translational motion output mechanism have a rotation axis R22. In the first parallelogram link mechanism, the second link, which is opposite to the transition link, is fixedly connected to the first translational motion output mechanism. The two ends of the second link have rotation axes Ra1 and Ra4, and the rotation axes R22, Ra1, and Ra4 are arranged parallel to each other.
[0013] Furthermore, there is a rotation axis R23 between the first connecting rod and the second connecting end, a rotation axis Ra3 at the end of the transition connecting rod that is rotatably connected to the second connecting rod on the left, and a rotation axis Ra2 at the first connecting end. The rotation axes R23, Ra3, and Ra2 are arranged parallel to each other.
[0014] Furthermore, the second translational motion output mechanism is slidably mounted on the stationary platform, and there are three fourth links. There are rotation axes R32 and R33 between two adjacent fourth links, and there is a rotation axis R34 between the fourth link and the moving platform. Among them, the rotation axes R32, R33, R34 and the translational motion output direction S2 are arranged parallel to each other.
[0015] Furthermore, the first branch assembly also includes multiple connecting rods, and at least two first translational motion output mechanisms include a first sub-translational motion output mechanism and a second sub-translational motion output mechanism. The first sub-translational motion output mechanism is fixedly connected to a second link via a connecting rod, and the second link is disposed opposite to a transition link. The second sub-translational motion output mechanism is rotatably connected to the first link via a connecting rod, and the connecting rod is fixed to the second sub-translational motion output mechanism. The transition link located between the second connecting end and the first connecting end is fixedly connected to the third link of the second parallelogram linkage mechanism via a connecting rod, and the third link disposed opposite to the third link is fixedly connected to the moving platform via a connecting rod.
[0016] According to another aspect of the present invention, a robot is provided, wherein at least a portion of the robot's motion structure moves in the motion manner of the aforementioned motion mechanism.
[0017] According to the technical solution of the present invention, the first branch assembly of the motion mechanism includes at least two first translational motion output mechanisms, a first parallelogram linkage mechanism, a second parallelogram linkage mechanism, and a first link. The first translational motion output mechanism is disposed on a stationary platform. One of the second links of the first parallelogram linkage mechanism is a transition link. The transition link has a first connecting end located between its two ends. The first connecting end is used to rotatably connect with the second link so that one end of the transition link forms a second connecting end. The transition link located between the second connecting end and the first connecting end is fixedly connected to the second parallelogram linkage mechanism. The moving platform is fixedly connected to the second parallelogram linkage mechanism. At least one first translational motion output mechanism is fixedly connected to the second link. At least one other first translational motion output mechanism is rotatably connected to the second connecting end through the first link. The second branch assembly includes a second translational motion output mechanism and a fourth link. The second translational motion output mechanism is rotatably connected to the moving platform through the fourth link. The moving platform moves along a spherical surface under the joint drive of the first and second translational motion output mechanisms. Thus, when the motion mechanism of this application linearly fits the motion trajectories of each structure through the processing module to control the motion platform to move along the spherical trajectory, the motion mechanism as a whole exhibits partial motion decoupling. The processing module is more likely to obtain the positive sign solution during the linear fitting process, thereby simplifying the fitting processes for kinematics, motion control and trajectory planning, and dynamic analysis. This solves the problem of overly complex fitting processes in existing three-translational parallel mechanisms when outputting spherical motion. Furthermore, the motion mechanism in this application consists only of lower pairs, resulting in a simpler structure, lower processing difficulty and cost, and easier installation. Attached Figure Description
[0018] The accompanying drawings, which form part of this application, 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 undue limitation of the invention. In the drawings:
[0019] Figure 1 A three-dimensional structural schematic diagram of an embodiment of the motion mechanism according to the present invention is shown;
[0020] Figure 2 It shows Figure 1 A schematic diagram of the overall motion model of the motion mechanism in the diagram;
[0021] Figure 3 It shows Figure 2A front view of the first independent loop P1 of the motion mechanism in the image;
[0022] Figure 4 It shows Figure 2 Side view of the second independent loop P2 of the motion mechanism in the image;
[0023] Figure 5 It shows Figure 1 The first process diagram in the simulation flow of the motion mechanism in the image;
[0024] Figure 6 It shows Figure 1 The second process diagram in the simulation flow of the motion mechanism;
[0025] Figure 7 It shows Figure 1 The third process diagram in the simulation flow of the motion mechanism in the image;
[0026] Figure 8 It shows Figure 1 The fourth process diagram in the simulation flow of the motion mechanism;
[0027] Figure 9 It shows Figure 1 The fifth process diagram in the simulation flow of the motion mechanism.
[0028] The above figures include the following reference numerals:
[0029] 10. Moving platform; 20. Static platform;
[0030] 30. First branch assembly; 31. First translational motion output mechanism; 311. First sub-translational motion output mechanism; 312. Second sub-translational motion output mechanism; 32. First parallelogram linkage mechanism; 321. Second link; 321b. Left second link; 321c. Right second link; 321d. Upper second link; 321a. Lower second link; 322. Transition link; 322a. First connecting end; 322b. Second connecting end; 33. Second parallelogram linkage mechanism; 331. Third link; 34. First link; 35. Connecting rod;
[0031] 40. Second branch assembly; 41. Second translational motion output mechanism; 42. Fourth link;
[0032] 50. Dynamic platform The trajectory of movement at the point. Detailed Implementation
[0033] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0034] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.
[0035] To address the problem that the fitting process of the existing three-translation parallel mechanism is too complex when outputting spherical motion, this application provides a motion mechanism and a robot having the same.
[0036] like Figure 1 As shown, the motion mechanism includes a moving platform 10, a stationary platform 20, a first branch assembly 30, and a second branch assembly 40. The first branch assembly 30 includes at least two first translational motion output mechanisms 31, a first parallelogram linkage mechanism 32, a second parallelogram linkage mechanism 33, and a first link 34. The first translational motion output mechanism 31 is disposed on the stationary platform 20. The first parallelogram linkage mechanism 32 has a plurality of second links 321, which are respectively the left second link 321b, the right second link 321c, the upper second link 321d, and the lower second link 321a. The upper second link 321d of the first parallelogram linkage mechanism 32 is a transition link 322. The transition link 322 has a first connecting end 322a located between its two ends. The first connecting end 322a is used to rotatably connect with the right second link 321c so that one end of the transition link 322 forms the second connecting end 322b. The transition link 322 located between the second connecting end 322b and the first connecting end 322a is fixedly connected to the second parallelogram linkage mechanism 33. The moving platform 10 is fixedly connected to the second parallelogram linkage mechanism 33. At least one first translational motion output mechanism 31 is fixedly connected to the lower second link 321a, and at least one other first translational motion output mechanism 31 is rotatably connected to the second connecting end 322b via the first link 34. The second branch assembly 40 includes a second translational motion output mechanism 41 and a fourth link 42. The second translational motion output mechanism 41 is rotatably connected to the moving platform 10 via the fourth link 42. The moving platform 10 moves along a spherical surface under the combined drive of the first translational motion output mechanism 31 and the second translational motion output mechanism 41.
[0037] Applying the technical solution of this embodiment, the first branch assembly 30 of the motion mechanism includes at least two first translational motion output mechanisms 31, a first parallelogram linkage mechanism 32, a second parallelogram linkage mechanism 33, and a first link 34. The first translational motion output mechanism 31 is disposed on the stationary platform 20. One of the second links 321 of the first parallelogram linkage mechanism 32 is a transition link 322. The transition link 322 has a first connecting end 322a located between its two ends. The first connecting end 322a is used to rotatably connect with the second link 321, so that one end of the transition link 322 forms a second connecting end 322b. The second connecting end 322b and the first connecting end 322a are located between the second connecting end 322a and the first connecting end 322a. The transition link 322 between a is fixedly connected to the second parallelogram linkage 33. The moving platform 10 is fixedly connected to the second parallelogram linkage 33. At least one first translational motion output mechanism 31 is fixedly connected to the second link 321. At least one other first translational motion output mechanism 31 is rotatably connected to the second connecting end 332b through the first link 34. The second branch assembly 40 includes a second translational motion output mechanism 41 and a fourth link 42. The second translational motion output mechanism 41 is rotatably connected to the moving platform 10 through the fourth link 42. The moving platform 10 moves along the spherical surface under the joint drive of the first translational motion output mechanism 31 and the second translational motion output mechanism 41. Thus, in this embodiment, when the motion mechanism linearly fits the motion trajectories of each structure through the processing module to control the motion platform 10 to move along the spherical trajectory, the motion mechanism as a whole exhibits partial motion decoupling. The processing module can more easily obtain the positive sign position solution during the linear fitting process, thereby simplifying the fitting processes for kinematics, motion control and trajectory planning, and dynamic analysis. This solves the problem of overly complex fitting processes in existing three-translational parallel mechanisms when outputting spherical motion. Furthermore, the motion mechanism in this embodiment consists only of lower pairs, resulting in a simpler structure, lower processing difficulty and cost, and easier installation.
[0038] Specifically, compared with the three-translation parallel mechanism in the prior art, the motion platform 10 of the motion mechanism in this embodiment has a larger range of motion, higher versatility, and can adapt to more types of motion needs.
[0039] like Figure 1 As shown, the first translational motion output mechanism 31 is slidably mounted on the static platform 20, and the motion trajectories of at least two first translational motion output mechanisms 31 are collinear. This arrangement ensures that the translational motion output directions of the multiple first translational motion output mechanisms 31 in the first branch assembly 30 are on the same straight line, further reducing the fitting difficulty in the linear fitting process; it also simplifies the motion output mode of the first translational motion output mechanism 31, making it easier to manufacture and implement.
[0040] In other embodiments not shown in the accompanying drawings, the first translational motion output mechanism is a parallelogram mechanism, comprising four fifth links rotatably connected to each other. One fifth link is mounted on a stationary platform, and the fifth link opposite to this fifth link is an output link for outputting translational motion. The motion trajectories of the output links of at least two first translational motion output mechanisms are collinear. This ensures that, on the one hand, the output links of the multiple first translational motion output mechanisms in the first branch assembly move along the same straight line, further reducing the fitting difficulty in the linear fitting process; on the other hand, it makes the structure of the first translational motion output mechanism more flexible and diverse, adapting to different working conditions and usage requirements, and also improving the processing flexibility of the operator.
[0041] In this embodiment, the first translational motion output mechanism 31 has a translational motion output direction S1, and the second translational motion output mechanism 41 has a translational motion output direction S2, with the translational motion output direction S1 perpendicular to the translational motion output direction S2. Thus, by cooperating with the first translational motion output mechanism 31 and the second translational motion output mechanism 41, it can be ensured that the moving platform 10 can move along the spherical surface.
[0042] In this embodiment, the second translational motion output mechanism 41 is slidably mounted on the stationary platform 20, and there are at least three fourth links 42. One end of the fourth link 42, which is used to connect to the second translational motion output mechanism 41, is fixed to the second translational motion output mechanism 41. This arrangement simplifies the translational motion output method of the second translational motion output mechanism 41 and ensures that the moving platform 10 performs translational motion on a spherical surface by increasing the number of fourth links 42.
[0043] In other embodiments not shown in the accompanying drawings, the second translational motion output mechanism is rotatably and slidably mounted on a stationary platform. There are at least two fourth links, one end of which is fixed to the second translational motion output mechanism for connection. The rotation axis of the second translational motion output mechanism is coaxial with its translational motion output direction S2. This arrangement makes the second translational motion output mechanism a cylindrical pair (i.e., possessing both rotational and translational degrees of freedom), reducing the number of fourth links and simplifying the linear fitting process of the motion mechanism. Simultaneously, this arrangement also makes the structure of the second translational motion output mechanism more flexible and diverse, adapting to different working conditions and usage requirements.
[0044] In this embodiment, the plane containing the first parallelogram linkage 32 is the first plane, and the plane containing the second parallelogram linkage 33 is the second plane; wherein, during the movement of the moving platform 10, the first plane and the second plane are arranged perpendicularly to each other. Thus, during the movement of the motion mechanism, the above arrangement ensures that the first branch assembly 30 can output multi-degree-of-freedom translational motion to the moving platform 10, ensuring that the moving platform 10 can translate along the spherical surface, while also simplifying the motion relationship between the first parallelogram linkage 32 and the second parallelogram linkage 33, further reducing the difficulty of linear fitting of the motion mechanism.
[0045] In this embodiment, the second parallelogram linkage mechanism 33 has four rotational connection points among its four third links 331, and the rotation axis R of the four rotational connection points is... b1 R b2 R b3 and R b4 They are set up in parallel to each other.
[0046] In this embodiment, the first link 34 and the first translational motion output mechanism 31 have a rotation axis R22. In the first parallelogram linkage mechanism 32, the second link 321, which is opposite to the transition link 322, is fixedly connected to the first translational motion output mechanism 31. The two ends of the second link 321 have rotation axes R. a1 and the axis of rotation R a4 Rotation axis R 22 Rotation axis R a1 and the axis of rotation R a4 They are arranged parallel to each other. The first connecting rod 34 and the second connecting end 322b have a rotation axis R. 23 The end of the transition link 322 that is rotatably connected to the second link 321b on the left has a rotation axis R. a3 The first connecting end 322a has a rotation axis R. a2 Rotation axis R 23 Rotation axis R a3 and the axis of rotation R a2 The components are arranged in parallel. This arrangement ensures that the rotation axis of the first parallelogram linkage 32 is parallel to the corresponding rotation axis of the first link 34, thus ensuring a simpler follow-up relationship between the motion trajectory of the first parallelogram linkage 32 and the motion trajectory of the first link 34, further reducing the difficulty of linear fitting of the motion mechanism.
[0047] In this embodiment, the second translational motion output mechanism 41 is slidably mounted on the static platform 20, and there are three fourth links 42, with a rotation axis R between two adjacent fourth links 42. 32and the axis of rotation R 33 The fourth link 42 and the moving platform 10 have a rotation axis R. 34 Among them, the axis of rotation R 32 Rotation axis R 33 Rotation axis R 34 The translational motion output directions S2 are arranged parallel to each other. This arrangement simplifies the motion relationship between the second translational motion output mechanism 41 and the three fourth links 42, reducing the difficulty of linear fitting of the motion mechanism.
[0048] Specifically, the arrangement of three fourth links 42 can ensure that the moving platform 10 can translate along a spherical trajectory while reducing the number of revolute pairs in the second branch assembly 40 and reducing the difficulty of linear fitting of the motion mechanism.
[0049] Optionally, the first branch assembly 30 further includes multiple connecting rods 35, and at least two first translational motion output mechanisms 31 include a first sub-translational motion output mechanism 311 and a second sub-translational motion output mechanism 312. The first sub-translational motion output mechanism 311 is fixedly connected to a second connecting rod 321 via a connecting rod 35, and the second connecting rod 321 is disposed opposite to a transition connecting rod 322. The second sub-translational motion output mechanism 312 is rotatably connected to a first connecting rod 34 via a connecting rod 35, and the connecting rod 35 is fixed to the second sub-translational motion output mechanism 312. The transition connecting rod 322, located between the second connecting end 322b and the first connecting end 322a, is fixedly connected to a third connecting rod 331 of the second parallelogram linkage mechanism 33 via a connecting rod 35, and the third connecting rod 331, disposed opposite to the third connecting rod 331, is fixedly connected to the moving platform 10 via a connecting rod 35. In this way, the above-mentioned arrangement of the connecting rod 35 can reserve corresponding activity space between the first sub-translational motion output mechanism 311, the second sub-translational motion output mechanism 312, the first parallelogram linkage mechanism 32, the second parallelogram linkage mechanism 33 and the moving platform 10, so as to avoid mutual interference between the various mechanisms during the movement process and improve the motion stability of the motion mechanism.
[0050] This embodiment also provides a robot (not shown), at least a portion of the robot's motion structure moving in the motion manner of the aforementioned motion mechanism.
[0051] The motion principle of the motion mechanism in this embodiment is as follows:
[0052] To facilitate the explanation of the kinematic derivation process of the motion mechanism, the three-dimensional structure of the motion mechanism is simplified into an overall kinematic model of the mechanism, and the specific structural kinematic pairs are simplified into kinematic nodes (the kinematic characteristics of the nodes are consistent with the kinematic characteristics of the original three-dimensional structural kinematic pairs).
[0053] like Figures 1 to 4As shown, let the static platform 20 be a rectangle with length and width of respectively. , The moving platform 10 is rectangular, with a length and width of [missing information]. , Establish a Cartesian static coordinate system on static platform 20. Cartesian moving coordinate system The origin of the static coordinate system. Located at the geometric center of the rectangular static platform 20, axis, The axes are perpendicular to and parallel to respectively (The first sub-translational motion output mechanism 311 is actually a sliding joint in the coordinate system, simplified to a point) ), (The second sub-translational motion output mechanism 312 is actually a sliding joint in the coordinate system, simplified to a point) The line connecting the origin of the moving coordinate system. Located at the geometric center point on the moving platform 10, The axis translates to the axis of rotation. , The axis is perpendicular to the axis of rotation. ; shaft and The axis is determined by the right-hand rule. The connecting rod 35, which is fixedly connected to the first sub-translational motion output mechanism 311, the connecting rod 35, which is fixedly connected to the second sub-translational motion output mechanism 312, and the fourth connecting rod 42, which is fixedly connected to the second translational motion output mechanism 41, are perpendicular to the static platform 20.
[0054] In the first branch assembly 30, the lengths of the connecting rod 35 fixedly connected to the first sub-translational motion output mechanism 311 and the connecting rod 35 fixedly connected to the second sub-translational motion output mechanism 312 are both... In the first parallelogram linkage mechanism 32, the lengths of the two second links 321 and the first link 34, which are rotatably connected to the transition link 322, are all... The length of the end of the transition link 322 furthest from the second connecting end 322b to the first connecting end 322a is: The length of the second link 321, which is positioned opposite the transition link 322, is The length of the third link 331, which is fixedly connected to the moving platform 10, is The fixed connection point of the first parallelogram linkage 32 and the second parallelogram linkage 33 The point is located at point (In the actual coordinate system, the first connecting end 322a is a point) ),point (In the actual coordinate system, the second connecting end 322b is a point) The midpoint of the line connecting the points. ,point The length of the transition link 322 between them is The length of the connecting rod 35 between the second parallelogram linkage 33 and the first parallelogram linkage 32 is... The length of the third link 331 adjacent to the third link 331 used for fixed connection with the moving platform 10 is... The length of the connecting rod 35 between the second parallelogram linkage 33 and the moving platform 10 is... ;
[0055] In the second branch assembly 40, there are three fourth links 42: one fourth link 42 rotatably connected to the moving platform 10, one fourth link 42 fixedly connected to the second translational motion output mechanism 41, and one fourth link 42 with both ends rotatably connected to the aforementioned fourth links 42. The length of the fourth link 42 fixedly connected to the second translational motion output mechanism 41 is... The length of the fourth link 42, which is rotatably connected to the fourth link 42 at both ends, is... The length of the fourth link 42, which is rotatably connected to the moving platform 10, is... ;
[0056] Let the line connecting point B1 (the fixed connection point between the connecting rod 35 connected to the first sub-translational motion output mechanism 311 and the first parallelogram linkage mechanism 32) and point C1 (the midpoint between the end of the transition link 322 furthest from the second connecting end 322b and the first connecting end 322a) be parallel to the line connecting point B1 (the midpoint between the end of the transition link 322 furthest from the second connecting end 322b and the first connecting end 322a). The angle between the positive axis and the positive axis is Let the line connecting point B2 (the point where the connecting rod 35 connecting the second sub-translational motion output mechanism 312 and the first connecting rod 34 are rotational connection points) and point C3 (the second connecting end 322b) be... and The angle between the positive axis and the positive axis is Let the line connecting D1 (the fixed connection point between the connecting rod 35 between the transition link 322 and the first parallelogram linkage 32 and the second parallelogram linkage 33, which is point D1 in the actual coordinate system) and E1 (the fixed connection point between the connecting rod 35 between the second parallelogram linkage 33 and the moving platform 10 and the second parallelogram linkage 33, which is point E1 in the actual coordinate system) be... and The angle between the positive axis and the positive axis is .point ,point All are located at the midpoint of the boundary of the moving platform 10.
[0057] In this embodiment, the derivation of the forward kinematics formula for the position of the motion mechanism is as follows:
[0058] Specifically, in the static coordinate system, the point on the static platform 20 , , The coordinates are respectively , , It is known that the first sub-translational motion output mechanism 311, the second sub-translational motion output mechanism 312, and the second translational motion output mechanism 41 respectively input... , , Displacement parameters, calculated on moving platform 10 Location .
[0059] Solving on the first independent loop P1, it is easy to see that in the static coordinate system: , .
[0060] Due to the constrained characteristics of the structure, Throughout the entire motion, it remains parallel to the static platform 20, that is... Therefore, we have:
[0061] ;
[0062] therefore, , The coordinates of the points are as follows:
[0063] ;
[0064] ;
[0065] like Figure 3 As shown, it is easy to see that the quadrilateral is... It is an isosceles trapezoid. According to Ptolemy's theorem, we know that:
[0066] ;
[0067] Formula 1
[0068] exist From the Law of Cosines, we can obtain:
[0069] ;
[0070] Formula 2
[0071] Solve equations 1 and 2 simultaneously and eliminate them. We can obtain:
[0072] ;
[0073] Formula 3
[0074] From Equation 3, we can see that when At that time, the mechanism was in a singular position and could not be calculated. The value;
[0075] From Equation 3, we can see that when When, it can be obtained The value of is given by:
[0076] ;
[0077] Formula 4
[0078] Specifically, in the first independent loop P1, it can be calculated using Equation 4. The coordinates of the point are:
[0079] ;
[0080] Therefore, we can obtain The coordinates of the point are:
[0081] ;
[0082] Specifically, the solution is found in the second loop P2, such as Figure 3 As shown, the following relationship exists:
[0083] ;
[0084] The positional relationship of the kinematic mechanism can be obtained The coordinates of the point are:
[0085] ;
[0086] Ultimately, we can obtain the dynamic platform 10. The coordinates of the point are:
[0087] ;
[0088] Right now:
[0089] ;
[0090] Formula 5
[0091] As can be seen from Equation 5, the motion mechanism in this embodiment has a symbolic positive position solution. The value is only related to related; The value is only related to , This means that the motion mechanism in this embodiment has partial decoupling of motion input and output, which is beneficial for kinematic and dynamic analysis of the motion mechanism and reduces the difficulty of controlling the mechanism.
[0092] Specifically, the process of verifying the translational characteristics of the motion mechanism is as follows:
[0093] To demonstrate that the motion mechanism in this embodiment has different translational characteristics, simulation experiments were conducted using MATLAB software to clarify the effects of the drive pair on the moving platform under different trajectories. The trajectory at point 50.
[0094] The motion trajectory of the drive pair 1: such as Figure 1 As shown, the first sub-translational motion output mechanism 311 is a prismatic joint and is also a driving joint. The second and third translational motion output mechanisms 312 are prismatic joints and are designed as driving joints. The second translational motion output mechanism 41 is a prismatic joint and is designed as a driving joint. , Subsidiary and The motion speed of the three drive pairs remains the same. Assume there are three drive pairs on the static platform 20. vice, vice, The secondary drive trajectory in time The relationship of change is as follows:
[0095] ;
[0096] According to the driving form of symbolic position positive solution, for the moving platform 10 The positional changes of the points are calculated and analyzed to obtain the dynamic platform 10. The diagram showing the change in point position is as follows Figure 5 As shown.
[0097] from Figure 5 The drive can be obtained from the middle vice, When the secondary speed is the same, the position change of the moving platform 10 only exists The axial direction has a numerical change, and the moving platform... The trajectory of motion at point 50 is a straight line in space, and the trajectory conforms to the linear motion of a rigid body.
[0098] Motion trajectory of the drive pair 2: Let the drive pair vice, The three drive pairs on the static platform 20 have different movement speeds. vice, vice, The secondary drive trajectory in time The relationship of change is as follows:
[0099] ;
[0100] According to the driving form of symbolic position positive solution, for the moving platform 10 The positional changes of the points are calculated and analyzed to obtain the dynamic platform. The trajectory of the movement at the point is 50. Figure 6 As shown, the moving platform The trajectory of motion at point 50 in the o-xyz space is as follows: Figure 7 As shown.
[0101] from Figure 6 As can be seen from this, in the drive sub vice, Different secondary velocities When the secondary rotation angle remains unchanged, the moving platform 10 is in direction, The direction and position change simultaneously, indicating that the moving platform 10 is able to Achieve bending and translation within a plane.
[0102] Motion trajectory of the drive pair 3: Assume three drive pairs on the static platform 20 vice, vice, The secondary drive trajectory in time The relationship of change is as follows:
[0103] ;
[0104] According to the driving form of symbolic position positive solution, for the moving platform 10 The positional changes of the points are calculated and analyzed to obtain the dynamic platform. The trajectory of the movement at the point is 50. Figure 8 As shown, the moving platform The trajectory of motion at point 50 in the o-xyz space is as follows: Figure 9 As shown.
[0105] from Figure 8 It can be seen that the dynamic platform 10 is in direction, The position of the direction changes simultaneously, indicating that the moving platform 10 is capable of... Achieve bending and translation within a plane.
[0106] In summary, the motion mechanism in this embodiment, by simply changing the driving speed of the drive pair, enables the moving platform 10 to achieve both linear and bending translational motion. Furthermore, the motion mechanism in this embodiment is capable of... plane and The bending and translation are realized in the plane, that is, the spherical motion in space is realized. It can be seen that the motion mechanism in this embodiment has partial motion decoupling, the structure is simpler and can realize perfect spherical motion in space.
[0107] As can be seen from the above description, the embodiments of the present invention achieve the following technical effects:
[0108] The first branch assembly of the motion mechanism includes at least two first translational motion output mechanisms, a first parallelogram linkage mechanism, a second parallelogram linkage mechanism, and a first link. The first translational motion output mechanism is mounted on a stationary platform. One of the second links of the first parallelogram linkage mechanism is a transition link. The transition link has a first connecting end located between its two ends. The first connecting end is used to rotatably connect with the second link so that one end of the transition link forms a second connecting end. The transition link located between the second connecting end and the first connecting end is fixedly connected to the second parallelogram linkage mechanism. The moving platform is fixedly connected to the second parallelogram linkage mechanism. At least one first translational motion output mechanism is fixedly connected to the second link. At least one other first translational motion output mechanism is rotatably connected to the second connecting end through the first link. The second branch assembly includes a second translational motion output mechanism and a fourth link. The second translational motion output mechanism is rotatably connected to the moving platform through the fourth link. The moving platform moves along a spherical surface under the combined drive of the first and second translational motion output mechanisms. Thus, when the motion mechanism of this application linearly fits the motion trajectories of each structure through the processing module to control the motion platform to move along the spherical trajectory, the motion mechanism as a whole exhibits partial motion decoupling. The processing module is more likely to obtain the positive sign solution during the linear fitting process, thereby simplifying the fitting processes for kinematics, motion control and trajectory planning, and dynamic analysis. This solves the problem of overly complex fitting processes in existing three-translational parallel mechanisms when outputting spherical motion. Furthermore, the motion mechanism in this application consists only of lower pairs, resulting in a simpler structure, lower processing difficulty and cost, and easier installation.
[0109] Obviously, the embodiments described above are merely some, not all, embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.
[0110] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.
[0111] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.
[0112] 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 motion mechanism, characterized in that, include: Dynamic platform (10); Static platform (20); The first branch assembly (30) includes at least two first translational motion output mechanisms (31), a first parallelogram linkage mechanism (32), a second parallelogram linkage mechanism (33), and a first link (34), wherein the first translational motion output mechanism (31) is disposed on the stationary platform (20); The first parallelogram linkage mechanism (32) has a plurality of second links (321), which are respectively a left second link (321b), a right second link (321c), an upper second link (321d), and a lower second link (321a). The upper second link (321d) of the first parallelogram linkage mechanism (32) is a transition link (322), and the transition link (322) has a first connecting end located between its two ends. 322a), the first connecting end (322a) is used to rotatably connect with the second connecting rod (321c) on the right side, so that one end of the transition connecting rod (322) forms the second connecting end (322b); the transition connecting rod (322) located between the second connecting end (322b) and the first connecting end (322a) is fixedly connected to the second parallelogram linkage mechanism (33), and the moving platform (10) is fixedly connected to the second parallelogram linkage mechanism (33); At least one of the first translational motion output mechanisms (31) is fixedly connected to the lower second link (321a), and at least one other of the first translational motion output mechanisms (31) is rotatably connected to the second connecting end (322b) through the first link (34); The second branch assembly (40) includes a second translational motion output mechanism (41) and a fourth link (42). The second translational motion output mechanism (41) is rotatably connected to the moving platform (10) through the fourth link (42). The moving platform (10) moves along the spherical surface under the joint drive of the first translational motion output mechanism (31) and the second translational motion output mechanism (41).
2. The motion mechanism according to claim 1, characterized in that, The first translational motion output mechanism (31) is slidably disposed on the stationary platform (20), and the motion trajectories of at least two of the first translational motion output mechanisms (31) are collinear.
3. The motion mechanism according to claim 1, characterized in that, The first translational motion output mechanism (31) is a parallelogram mechanism. The first translational motion output mechanism (31) includes four fifth links that are rotatably connected to each other. One of the fifth links is set on the stationary platform (20). The fifth link that is set opposite to the fifth link is the output link for outputting translational motion. The motion trajectories of at least two output links of the first translational motion output mechanism (31) are collinear.
4. The motion mechanism according to claim 1, characterized in that, The first translational motion output mechanism (31) has a translational motion output direction S1, and the second translational motion output mechanism (41) has a translational motion output direction S2, wherein the translational motion output direction S1 is perpendicular to the translational motion output direction S2.
5. The motion mechanism according to claim 1, characterized in that, The second translational motion output mechanism (41) is slidably mounted on the stationary platform (20). There are at least three fourth links (42), one end of which is fixed to the second translational motion output mechanism (41) for connection; or... The second translational motion output mechanism (41) is rotatably and slidably mounted on the stationary platform (20). There are at least two fourth links (42). One end of the fourth link (42) is used to connect with the second translational motion output mechanism (41) and is fixed on the second translational motion output mechanism (41). The rotation axis of the second translational motion output mechanism (41) is coaxial with the translational motion output direction S2 of the second translational motion output mechanism (41).
6. The motion mechanism according to claim 1, characterized in that, The plane in which the first parallelogram linkage mechanism (32) is located is the first plane, and the plane in which the second parallelogram linkage mechanism (33) is located is the second plane; wherein, during the movement of the moving platform (10), the first plane and the second plane are set perpendicular to each other.
7. The motion mechanism according to claim 1, characterized in that, The first connecting rod (34) and the first translational motion output mechanism (31) have a rotation axis R. 22 In the first parallelogram linkage mechanism (32), a second link (321) opposite to the transition link (322) is fixedly connected to the first translational motion output mechanism (31). The two ends of the second link (321) have rotation axes R. a1 and the axis of rotation R a4 The rotation axis R 22 The rotation axis R a1 and the axis of rotation R a4 They are set up in parallel to each other.
8. The motion mechanism according to claim 1, characterized in that, The first connecting rod (34) and the second connecting end (322b) have a rotation axis R. 23 The end of the transition link (322) that is rotatably connected to the second link (321b) on the left has a rotation axis R. a3 The first connecting end (322a) has a rotation axis R. a2 The rotation axis R 23 The rotation axis R a3 and the axis of rotation R a2 They are set up in parallel.
9. The motion mechanism according to claim 5, characterized in that, The second translational motion output mechanism (41) is slidably mounted on the stationary platform (20). There are three fourth links (42). There are rotation axes R32 and R33 between two adjacent fourth links (42). There is a rotation axis R34 between the fourth link (42) and the moving platform (10). The rotation axes R32, R33, R34 and the translational motion output direction S2 are arranged parallel to each other.
10. The motion mechanism according to claim 1, characterized in that, The first branch assembly (30) also includes a plurality of connecting rods (35), and at least two of the first translational motion output mechanisms (31) include a first sub-translational motion output mechanism (311) and a second sub-translational motion output mechanism (312). The first sub-translational motion output mechanism (311) is fixedly connected to the second connecting rod (321) via the connecting rod (35), and the second connecting rod (321) is arranged opposite to the transition connecting rod (322); The second sub-translational motion output mechanism (312) is rotatably connected to the first connecting rod (34) via the connecting rod (35), and the connecting rod (35) is fixed on the second sub-translational motion output mechanism (312); The transition link (322) located between the second connecting end (322b) and the first connecting end (322a) is fixedly connected to the third link (331) of the second parallelogram linkage mechanism (33) through the connecting rod (35). The third link (331) which is opposite to the third link (331) is fixedly connected to the moving platform (10) through the connecting rod (35).
11. A robot, characterized in that, At least a portion of the robot's motion structure moves in the motion manner of the motion mechanism described in any one of claims 1 to 10.