5-dof serial-parallel hybrid robot and working method thereof

Abstract

The application provides a 5-DOF serial-parallel hybrid robot and a working method, and the robot has the characteristics of simple structure, high rigidity and good dexterity, and is mainly composed of a moving trolley, a rotating platform installed on the moving trolley, a parallel mechanism installed on the rotating platform, and an end effector. The rotating platform is used for adjusting the preoperative pose of a surgical instrument; the moving platform of the parallel mechanism is installed with the surgical instrument as the end effector to perform a surgical operation; the fixed platform of the parallel mechanism is fixed in a sliding groove of the rotating platform, and the rotating platform is fixed on the moving trolley through screw connection. The design scheme can reduce the volume of the robot and increase the degrees of freedom of the robot.

Description

Technical Field

[0001] This invention belongs to the field of medical robot technology, specifically a 5-DOF serial-parallel embedded robot and its working method. Background Technology

[0002] Minimally invasive surgical robots are among the most widely used robots in the field of medical robotics. They have the same therapeutic effect as traditional surgery, can enter the human body through natural cavities to perform surgery, and have the advantages of less trauma, less pain, lower risk of surgical infection, and faster postoperative recovery.

[0003] Existing minimally invasive surgical robots are mainly classified into two types based on how they achieve telecentric motion: First, telecentric motion is achieved through control algorithms, such as the DLR MIRO lightweight minimally invasive robot, the Trans Enterix surgical robot, and the ZEUS surgical robot system. These robots have complex control systems, redundant degrees of freedom, are inconvenient to operate, and accumulate errors. Second, telecentric motion is achieved through the constraints of the mechanism itself, meaning it possesses the degree of freedom for telecentric motion without external constraints. Parallel telecentric mechanisms are a typical type of structure that can output telecentric motion through mechanism constraints. Each branch of the parallel mechanism is driven by a different motor, moving independently of each other. The moving platform and the base are connected by branches, and the processing and motion errors of each branch are canceled out by the mutual correction between branches. Therefore, it has characteristics such as high end effector positional accuracy, high overall structural rigidity, and strong load capacity, and is therefore applied in minimally invasive surgical robots. Summary of the Invention

[0004] The technical problem to be solved by this invention is to overcome the shortcomings of the aforementioned background technology and to provide a 5-DOF serial-parallel embedded robot and its working method. This mechanism has a 2R rotating platform for preoperative posture adjustment and a mobile trolley, and features simple structure, high rigidity, and good maneuverability, making it applicable to the field of minimally invasive surgery.

[0005] The technical solution of this invention is: A 5-DOF serial-parallel embedded robot includes a mobile vehicle, a rotating platform mounted on the mobile vehicle, a parallel mechanism mounted on the rotating platform, and an end effector. The aforementioned rotating platform comprises, from bottom to top, a trolley fixing frame, a fixed platform mounting frame, and a fixed platform; wherein the trolley fixing frame is fixedly connected to the moving trolley; the fixed platform mounting frame is mounted on the trolley fixing frame via a rotating joint; and the fixed platform is mounted in the arc-shaped groove on the inner side of the fixed platform mounting frame. The parallel mechanism consists of three branch mechanisms, namely the first branch, the second branch, and the third branch; The aforementioned first branch chain consists of a first motor support, a first bearing housing, a first Y-axis drive motor, an X-axis, a first driven wheel, a first driving wheel, a first synchronous belt, a first connecting rod, and a second connecting rod. The first bearing housing is fixed above a fixed platform. The X-axis is mounted and passes through the first bearing housing. The first motor support is located directly above the first bearing housing and is fixedly connected to the X-axis. The first Y-axis drive motor is mounted on the first motor support. A Y-axis shaft hole is provided at the lower left corner of the first motor support, and the Y-axis is mounted in this hole with its two ends extending outwards from the front and rear sides of the hole, respectively. The driven wheel is mounted on the front extended end of the Y-axis, the driving wheel is mounted on the output shaft of the Y-axis drive motor, and the first synchronous belt is mounted on the driving wheel and the driven wheel. The lower end of the first connecting rod is fixed to the rear extended end of the Y-axis, the upper end of the first connecting rod is connected to the lower end of the second connecting rod via a revolute joint, and the upper end of the second connecting rod is connected to the left side of the end effector via a revolute joint. The aforementioned second branch chain consists of a second motor support, a second bearing housing, a second Y-axis drive motor, a second driven wheel, a second driving wheel, a second synchronous belt, a Y-axis, a first arc-shaped connecting rod, and a second arc-shaped connecting rod. The second motor support is fixed below the fixed platform, and the second bearing housing is fixed above the fixed platform. The second Y-axis drive motor is mounted on the second motor support. The Y-axis is mounted on the bearing housing, with its two ends extending from the front and rear sides of the bearing housing, respectively. The second driven wheel is mounted on the front extended end of the Y-axis, the second driving wheel is mounted on the output shaft of the second Y-axis drive motor, and the second synchronous belt is mounted on the second driving wheel and the second driven wheel. The lower end of the first arc-shaped connecting rod is fixed to the rear extended end of the Y-axis, the upper end of the first arc-shaped connecting rod is connected to the upper end of the second arc-shaped connecting rod via a revolute joint, and the second arc-shaped connecting rod is connected to the end effector via a cylindrical joint. The third branch structure is the same as the first branch structure, and is symmetrically distributed along the Y direction; the upper end of its second link is connected to the right side of the end effector through a revolute joint.

[0006] A method for operating a 5-DOF serial-parallel embedded robot, characterized by comprising the following processes: The rotation of the first Y-axis drive motor drives the first driving wheel to rotate; the rotation of the first driving wheel transmits power to the first driven wheel through the first synchronous belt; the lower end of the first connecting rod is fixedly connected to the first driven wheel, so the rotation of the first driven wheel drives the first connecting rod to rotate; the upper end of the first connecting rod is connected to the lower end of the second connecting rod through a revolute joint, so the rotation of the first connecting rod drives the rotation of the second connecting rod; the upper end of the second connecting rod is connected to the end effector through a revolute joint, so the rotation of the second connecting rod drives the rotation of the end effector. Because the third branch has the same structure as the first branch and is symmetrically distributed along the Y direction, the movements of the first and third branches together control the vertical movement of the end effector.

[0007] The movement of the second Y-axis drive motor drives the rotation of the second driving wheel; the rotation of the second driving wheel transmits power to the second driven wheel through the second synchronous belt; the lower end of the first arc-shaped connecting rod is fixedly connected to the second driven wheel, so the rotation of the second driven wheel drives the rotation of the first arc-shaped connecting rod; the upper end of the first arc-shaped connecting rod is connected to the lower end of the second arc-shaped connecting rod through a revolute joint, so the rotation of the first arc-shaped connecting rod drives the rotation of the second arc-shaped connecting rod; the upper end of the second arc-shaped connecting rod is connected to the end effector through a revolute joint, so the rotation of the second arc-shaped connecting rod drives the rotation of the end effector.

[0008] The beneficial effects of this invention are: it employs a serial-parallel interlocking mechanism composed of a 2R rotating platform, a mobile carriage, and a parallel mechanism; the robot's control system can be integrated inside the mobile carriage, reducing the overall size of the mechanism; preoperatively, the 2R rotating platform can be used for posture adjustment according to surgical needs. After posture adjustment, the surgical instruments are mounted on the moving platform of the parallel mechanism. The output motion of the surgical instruments consists of two rotational degrees of freedom around the telecentric point and one translation through the telecentric point, thus meeting the application requirements of minimally invasive surgical robots. Furthermore, the overall robot structure features a large workspace, simple structure, and ease of control.

[0009] The 5-DOF serial-parallel interlocking robot is characterized in that: the axes of the rotary joints in all links of the first and third branches are parallel to each other and parallel to the output shafts of the first and third drive motors.

[0010] The 5-DOF serial-parallel interlocking robot is characterized in that the axes of all the rotating joints in the second branch converge at point O, which is a spatial spherical 4-bar linkage. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the overall structure of the 5-DOF serial-parallel embedded minimally invasive surgical robot described in this invention; Figure 2 This is a schematic diagram of the first branch structure of the 5-DOF serial-parallel embedded minimally invasive surgical robot described in this invention; Figure 3 This is a schematic diagram of the first branch of the Hooke's hinge structure of the 5-DOF serial-parallel interlocked minimally invasive surgical robot described in this invention; Figure 4 This is a schematic diagram of the second branch structure of the 5-DOF serial-parallel embedded minimally invasive surgical robot described in this invention; Figure 5 This is a schematic diagram of the 2R rotating platform structure of the 5-DOF serial-parallel interconnected minimally invasive surgical robot described in this invention; The labels in the diagram are as follows: 1-Mobile trolley; 2-Trolley mounting frame; 3-Fixed platform mounting frame; 4-First branch chain; 5-Second branch chain; 6-End effector; 7-Fixed platform; 401-First bearing seat; 402-X-axis; 403-First driving wheel; 404-First driven wheel; 405-First motor support; 406-First synchronous belt; 407-First Y-axis drive motor; 408-Y-axis; 409-First connecting rod; 410-Second connecting rod; 501-Second Y-axis drive motor; 502-Second motor support; 503-Second driving wheel; 504-Second synchronous belt; 505-Second driven wheel; 506-Second Y-axis; 507-Second bearing seat; 508-First arc-shaped connecting rod; 509-Second arc-shaped connecting rod. Detailed Implementation

[0012] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0013] Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 The motion mechanism of the 5-DOF serial-parallel interconnected minimally invasive surgical robot shown includes a mobile cart, a 2R rotating platform, and a 2URR-RRC parallel connection mechanism.

[0014] The 2URR-RRC parallel mechanism includes a first branch 4, a second branch 5, and a third branch connected in parallel between the stationary platform 7 and the end effector 6. The first branch 4 sequentially includes a first Y-axis drive motor 407 connected between the stationary platform 7 and the end effector 6. This motor is fixed to a Hooke-like hinge via a first motor support 405 (comprising an X-axis 402 and a first Y-axis 408). The first Y-axis 408 fixes a first driven wheel 404 and a first connecting rod 409. The upper end of the first connecting rod 409 and the lower end of the second connecting rod 410 are connected via a revolute joint. The upper end of the second connecting rod 410 is connected to the end effector 6 via a revolute joint. The axes of all the aforementioned revolute joints are perpendicular to the X-axis 402 axis of the revolute joint of the Hooke-like hinge (composed of the X-axis 402 and the first Y-axis 408) and parallel to the first Y-axis 408 axis of the revolute joint.

[0015] In the first branch, all the axes of the revolute joints except for the X-axis 402 are parallel to each other.

[0016] The second branch sequentially includes a second Y-axis drive motor 501 connected between the stationary platform 7 and the end effector 6, which is fixed to the stationary platform 7 via a second motor support 502. A second Y-axis 506 fixes the second driven wheel 505 and the lower end of the first arc-shaped connecting rod 508. The upper end of the first arc-shaped connecting rod 508 and the lower end of the second arc-shaped connecting rod 509 are connected via a revolute joint. The upper end of the second arc-shaped connecting rod 509 is connected to the end effector 6 via a cylindrical joint. All the aforementioned revolute joints converge at... O point.

[0017] In the second branch, the axes of all revolute joints always converge at point [point missing]. O Furthermore, all the revolute joints in the second branch and the revolute joint X-axis 402 in the first branch constitute an instantaneous spherical 4R mechanism.

[0018] The structure of the third branch is the same as that of the first branch and can be replaced by the first branch. The first branch and the third branch are coaxial with the Hooke's joint X-axis 402. O The point is located at the midpoint of the line connecting the rotating parts.

[0019] In the first branch, all the axes of the revolute joints except for the X-axis 402 are parallel to each other.

[0020] In this invention, the moving platform has a center point around which it moves. O Two rotational degrees of freedom and one along the axis of the moving platform and passing through O One degree of freedom of movement for a point. The drive of the parallel mechanism is the first revolute joint on each branch. The drive method is belt drive driven by a motor. When driven, it can drive the surgical instruments fixed on the moving platform to perform spatial movement to complete the surgical task. (The specific technology will not be described in detail here.)

Claims

1. A 5-DOF serial-parallel embedded robot, comprising a mobile vehicle (1), a rotating platform mounted on the mobile vehicle, a parallel mechanism mounted on the rotating platform, and an end effector (6); The rotating platform consists of a trolley fixing frame (2), a fixed platform mounting frame (3), and a fixed platform (7) from bottom to top. The trolley fixing frame (2) is fixedly connected to the moving trolley (1). The fixed platform mounting frame (3) is mounted on the trolley fixing frame (2) through a rotating joint. The fixed platform (7) is installed in the arc groove inside the fixed platform mounting frame (3). The parallel mechanism consists of three branch mechanisms, namely the first branch (4), the second branch (5), and the third branch; The first branch (4) consists of a first motor support (405), a first bearing housing (401), a first Y-axis drive motor (407), an X-axis (402), a first driven wheel (404), a first driving wheel (403), a first synchronous belt (406), a first Y-axis (408), a first connecting rod (409), and a second connecting rod (410); wherein the first bearing housing (401) is mounted above the rotating platform; the X-axis (402) is mounted and passes through the first bearing housing (401); the first motor support (405) is located directly above the first bearing housing and is fixedly connected to the X-axis; the first Y-axis drive motor (407) is mounted on the first motor support (405); the first motor support... (405) A Y-axis hole is provided in the lower left corner. The first Y-axis (408) is installed in the Y-axis hole and its two ends extend out of the front and rear sides of the Y-axis hole respectively. The driven wheel (404) is installed on the front extended end of the first Y-axis (408). The driving wheel (403) is installed on the output shaft of the Y-axis drive motor (407). The first synchronous belt (406) is installed on the driving wheel (403) and the driven wheel (404). The lower end of the first connecting rod (409) is fixed to the rear extended end of the first Y-axis (408). The upper end of the first connecting rod (409) is connected to the lower end of the second connecting rod (410) through a rotating joint. The upper end of the second connecting rod (410) is connected to the left side of the end effector (6) through a rotating joint. The aforementioned second branch consists of a second motor support (502), a second bearing housing (507), a second Y-axis drive motor (501), a second driven wheel (505), a second driving wheel (503), a second synchronous belt (504), a second Y-axis (506), a first arc-shaped connecting rod (508), and a second arc-shaped connecting rod (509); wherein the second motor support (502) is fixed below the fixed platform (7), and the second bearing housing (507) is installed above the rotating platform; the second Y-axis drive motor (501) is installed on the second motor support (502); and the second Y-axis (506) is installed on the bearing housing and Its two ends extend out of the front and rear sides of the bearing housing, respectively; the second driven wheel (505) is installed on the front extended end of the second Y-axis (506), the second driving wheel (503) is installed on the output shaft of the second Y-axis drive motor (501), and the second synchronous belt (504) is installed on the second driving wheel (503) and the second driven wheel (505); the lower end of the first arc-shaped connecting rod (508) is fixed to the rear extended end of the Y-axis, the upper end of the first arc-shaped connecting rod (508) is connected to the lower end of the second arc-shaped connecting rod (509) through a revolute joint, and the upper end of the second arc-shaped connecting rod (509) is connected to the end effector (6) through a cylindrical joint; The third branch structure is the same as the first branch structure, and is symmetrically distributed along the Y direction; the upper end of its second link is connected to the right side of the end effector through a revolute joint.

2. The 5-DOF serial-parallel hybrid robot according to claim 1, characterized in that: The axes of the revolute joints in all links of the first and third branches are parallel to each other and parallel to the output shafts of the first and third drive motors.

3. The 5-DOF serial-parallel hybrid robot of claim 1, wherein: The axes of all revolute joints in the second branch converge at point O.

4. The working method of the 5-DOF series-parallel hybrid robot according to claim 1, characterized in that Includes the following processes: The rotation of the first Y-axis drive motor (407) drives the first drive wheel (403) to rotate; the rotation of the first drive wheel (403) transmits power to the first driven wheel (404) through the first synchronous belt (406); the lower end of the first connecting rod (409) is fixedly connected to the first driven wheel (404), so the rotation of the first driven wheel (404) drives the first connecting rod (409) to rotate; the upper end of the first connecting rod (409) is connected to the lower end of the second connecting rod (410) through a revolute joint, so the rotation of the first connecting rod (409) drives the second connecting rod (410) to rotate; the upper end of the second connecting rod (410) is connected to the end effector (6) through a revolute joint, so the rotation of the second connecting rod (410) drives the end effector (6) to rotate; because the third branch structure is the same as the first branch and is symmetrically distributed along the Y direction, the movement of the first branch and the third branch together control the movement of the end effector (6) in the vertical direction; The movement of the second Y-axis drive motor (501) drives the rotation of the second drive wheel (503); the rotation of the second drive wheel (503) transmits power to the second driven wheel (505) through the second synchronous belt (504); the lower end of the first arc-shaped connecting rod (508) is fixedly connected to the second driven wheel (505), so the rotation of the second driven wheel (505) drives the first arc-shaped connecting rod (508) to rotate; the upper end of the first arc-shaped connecting rod (508) is connected to the lower end of the second arc-shaped connecting rod (509) through a revolute joint, so the rotation of the first arc-shaped connecting rod (508) drives the second arc-shaped connecting rod (509) to rotate; the upper end of the second arc-shaped connecting rod (509) is connected to the end effector (6) through a revolute joint, so the rotation of the second arc-shaped connecting rod (509) drives the rotation of the end effector (6).

Images