Medicine grabbing manipulator and kinetic analysis method

Abstract

The invention discloses a medicine grabbing manipulator which comprises a horizontal movement mechanism, a lifting mechanism, a swing mechanism and a tail end executing mechanism, the horizontal movement mechanism is used for driving the tail end executing mechanism to horizontally move in the extending direction of a medicine frame, and the lifting mechanism is used for driving the tail end executing mechanism to move up and down. The swing mechanism is used for driving the tail end executing mechanism to rotate, and the tail end executing mechanism is used for clamping medicine.

Description

Technical Field

[0001] This invention relates to the field of robotic arms, and more particularly to a drug-grabbing robotic arm and a dynamic analysis method thereof. Background Technology

[0002] Currently, most pharmacies rely on manual dispensing of medications, and larger pharmacies often require multiple staff members. These staff members need to spend time locating the medications, resulting in high costs and low efficiency. With robots becoming increasingly common across various industries, automated medication dispensing using robots represents a future development direction. Summary of the Invention

[0003] The main objective of this invention is to provide a drug-grabbing robotic arm and a dynamic analysis method, which can realize the automatic picking and placing of drugs.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a drug gripping robot, comprising a horizontal motion mechanism, a lifting mechanism, a rotary mechanism, and an end effector, wherein the horizontal motion mechanism is used to drive the end effector to move horizontally along the direction of the drug rack, the lifting mechanism is used to drive the end effector to move up and down, the rotary mechanism is used to drive the end effector to rotate, and the end effector is used to grip the drug; The horizontal moving mechanism includes an upper sliding block mechanism and a lower sliding block mechanism. The lower sliding block mechanism includes a lower base plate, a first coupling, a bearing seat, two lower sliding rail pads, two lower sliding rails, a lower sliding block, a lower bearing plate, a first servo motor, and a first ball screw. The lower base plate extends along the moving direction of the end effector. The two lower sliding rail pads are arranged parallel to each other on the lower base plate and extend along the moving direction of the end effector. The two lower sliding rails are respectively arranged on the two lower sliding rail pads. The lower sliding rails and the lower sliding rail pads have the same extending direction and the same length. The two ends of the lower sliding rails are aligned with the two ends of the corresponding lower sliding rail pads. Two lower sliding blocks are arranged on each lower sliding rail. The lower bearing plate is fixed on four lower sliding blocks. The first ball screw is located between the two lower sliding rails and parallel to the lower sliding rails. The two ends of the first ball screw are respectively supported on two bearing seats by bearings. The two bearing seats are fixed on the lower base plate. The first ball screw is mounted on the lower base plate by a first servo motor mounting plate and is located at one end of the first ball screw. The output shaft of the first servo motor is connected to the first ball screw through the first coupling.

[0005] Preferably, the upper slide block mechanism includes an upper base plate, two upper slide rail pads disposed on the lower surface of the upper base plate, two upper slide rails, an upper slide block, and an upper support plate. The two upper slide rail pads correspond one-to-one with the two lower slide rail pads. Each lower slide rail pad is provided with an upper slide rail on its lower surface. Two upper slide blocks are disposed on each upper slide rail. The upper support plate is disposed on the four upper slide blocks.

[0006] Preferably, the lifting mechanism includes a vertically arranged back plate, a second ball screw vertically and rotatably arranged on the back plate, a movable stage arranged on the nut of the second ball screw, guide rods arranged on both sides of the second ball screw along the horizontal movement direction, and a drive motor. The upper and lower ends of the back plate are respectively arranged on the upper bearing plate and the lower bearing plate. The two guide rods are vertically arranged and symmetrically arranged relative to the second ball screw. The two ends of each guide rod are fixed to the back plate by shaft support brackets. The movable stage is slidably arranged on the guide rod. When the second ball screw drives the movable stage to move, the movable stage slides relative to the guide rod. The drive motor is mounted on the back plate through a drive motor mounting plate. The drive motor is connected to the second ball screw through a second coupling.

[0007] Preferably, the rotary mechanism includes a first support cylinder vertically arranged, a first mounting plate arranged on the first support cylinder, a first ring gear rotatably arranged on the first mounting plate, a first support plate arranged on the first ring gear, and a magnetic chuck arranged on the first support plate. The lower end of the first support cylinder is supported on a moving platform. A rotary bearing is arranged on the upper surface of the first mounting cylinder at the outer edge. The first ring gear is arranged inside the rotary bearing and can rotate relative to the rotary bearing. The first support plate is arranged on the first ring gear. The magnetic chuck is arranged on the first support plate. A through hole is arranged in the middle of the magnetic chuck. A copper sleeve is arranged in the through hole. The upper end of the copper sleeve is aligned with the upper surface of the magnetic chuck, and the lower end of the copper sleeve extends from the lower surface of the magnetic chuck. The rotary mechanism also includes a hydraulic cylinder and a mounting cylinder. The cylinder body of the hydraulic cylinder is disposed inside a copper sleeve, the piston rod of the hydraulic cylinder extends downward, the mounting cylinder opens upward, the upper end of the mounting cylinder is disposed on a first support plate, the lower end of the copper sleeve is inserted into the mounting cylinder, the piston rod of the hydraulic cylinder protrudes from the lower end of the mounting cylinder, a limit cylinder is provided at the lower end of the mounting cylinder, and the piston rod is inserted into the limit cylinder.

[0008] Preferably, the rotary mechanism further includes a first rotary motor, which is fixed to the lower surface of the first mounting plate. A first rotary gear is provided on the output shaft of the first rotary motor, and the first ring gear is an internal gear. The first rotary gear meshes with the first ring gear.

[0009] Preferably, the end effector includes an adsorption plate adsorbed on a magnetic chuck, a second support cylinder disposed on the adsorption plate, a third support cylinder rotatably supported on the second support cylinder, a support base movably supported on the third support cylinder, a first linkage arm, a second linkage arm, a third linkage arm, a gripper mounting base, and a gripper. A lifting screw is disposed within the support base, the upper end of which is fixed to the lower surface of the top of the support base. A lifting nut is disposed on the lifting screw, the lifting nut being threadedly engaged with the lifting screw. The lifting nut is rotatably disposed within the third support cylinder and cannot move up or down relative to the third support cylinder.

[0010] Preferably, the lower end of the first linkage arm is hinged to the support base, the hinge axis of the first linkage arm and the support base is horizontally arranged, the upper end of the first linkage arm is hinged to the lower end of the second linkage arm, the hinge axis of the first linkage arm and the second linkage arm is parallel to the hinge axis of the first linkage arm and the support base, one end of the third linkage arm is hinged to the upper end of the second linkage arm, the hinge axis of the third linkage arm and the second linkage arm is parallel to the hinge axis of the first linkage arm and the support base, and a gripper mounting seat is rotatably provided at the other end of the third linkage arm, and a gripper is provided on the gripper mounting seat, the gripper mounting seat is rotatable relative to the third linkage arm and the rotation axis is parallel to the extension direction of the third linkage arm.

[0011] Preferably, the end effector is subjected to dynamic analysis through the following steps: Step 1: Select any point on the i-th link. The velocity of this point is expressed as follows: (1), Let r be the fixed position vector of any point in the coordinate system of the i-th link itself, and let r be the position vector of any point in the global coordinate system of the end effector. i = 1, 2, 3, 4, the first link is the first linkage arm, the second link is the second linkage arm, the third link is the third linkage arm, and the fourth link is the gripper mounting base; Let be the homogeneous transformation matrix from the coordinate system of the support to the coordinate system of the i-th link; Let j be the joint variable of the j-th joint; Joint velocity; Step 2: Represent formula (1) using a matrix, and obtain: (2); Step 3: Kinetic energy of the i-th link for: (3), in, For point The mass of the micro-element, , where is the inertia tensor of the i-th link; Step 4: Since there are motors between the various links, these motors also provide some kinetic energy to the links. Therefore, the above equation should be: (4), in, Let be the inertia of the motor at the j-th shutdown point; Step 5: Calculate the total potential energy of the end effector using formula (5): (5), in, Let gravitational acceleration vector be , which can be represented as , It is the acceleration due to gravity. Let the mass of the i-th link be denoted as . Step 6: Obtain the Lagrange function according to formulas (4) and (5): L=KP (6), Step 7: Substitute formula (6) into the Lagrange equation to obtain the dynamic equation of the end effector: (7), in, For the action in the The first joint The generalized force of a link.

[0012] Preferably, They are respectively , This is the homogeneous transformation matrix between the support and the first link. This is the homogeneous transformation matrix between the support and the second link. This is the homogeneous transformation matrix between the support and the third link. Let be the homogeneous transformation matrix between the support and the fourth link, and , , , , , , , It is the homogeneous transformation matrix between the support and the first link. It is the homogeneous transformation matrix between the first link and the second link. It is the homogeneous transformation matrix between the second and third links. It is the homogeneous transformation matrix between the 3rd and 4th links, and: , in, Let be the translation of the coordinate system of the first link relative to the coordinate system of the support in the z-axis direction. , in, Let be the rotation angle of the second link relative to the first link. The length of the first link. , in, Let be the rotation angle of the third link relative to the second link. The length of the second link.

[0013] in, Let be the rotation angle of the fourth link relative to the third link. This is the length of the third link.

[0014] Compared with the prior art, the present invention has the following beneficial effects: This invention designs a robotic arm capable of automatically grasping medicines. The robotic arm can move along the direction of the pharmacy cabinet. When the robotic arm moves to a designated position, it can grasp the medicine by controlling the gripper. At the same time, this invention also provides a dynamic analysis, which provides the basis for controlling the gripper. Attached Figure Description

[0015] Figure 1 and Figure 2 These are perspective views of the invention from different angles; Figure 3 This is a structural diagram of the rotary mechanism and the end effector; Figure 4 This is a cross-sectional view of the rotary mechanism; Figure 5 This is a cross-sectional view of the end effector; Figure 6 This is a magnified view of point A; Figure 7 This is a 3D view of the end effector. Detailed Implementation

[0016] The following description is intended to disclose the invention and enable those skilled in the art to implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art.

[0017] Example 1 A drug-grabbing robot includes a horizontal motion mechanism, a lifting mechanism, a rotary mechanism, and an end effector. The horizontal motion mechanism drives the end effector to move horizontally along the direction of the drug shelf. The lifting mechanism drives the end effector to move up and down. The rotary mechanism drives the end effector to rotate. The end effector is used to grip the drug.

[0018] The horizontal moving mechanism includes an upper sliding block mechanism 2 and a lower sliding block mechanism 1. The lower sliding block mechanism 1 includes a lower base plate 106, a first coupling 102, a bearing seat 103, two lower sliding rail pads 107, two lower sliding rails 109, a lower slider 108, a lower bearing plate 104, a first servo motor 101, and a first ball screw 110. The lower base plate 106 extends along the moving direction of the end effector. The two lower sliding rail pads 107 are arranged in parallel on the lower base plate 106 and extend along the moving direction of the end effector. The two lower sliding rails 109 are respectively arranged on the two lower sliding rail pads 107. The lower sliding rails 109 and the lower sliding rail pads 107 extend in the same direction and have the same length. The two ends of the lower sliding rails 109 are... Aligned with the two ends of the corresponding lower slide block 107, two lower slide blocks 108 are provided on each lower slide 109. The lower support plate 104 is fixed on the four lower slide blocks 108. The first ball screw 110 is located between the two lower slides 109 and parallel to the lower slides 109. The two ends of the first ball screw 110 are respectively supported by bearings on two bearing seats 103. The two bearing seats 103 are fixed on the lower base plate 106. The first servo motor 101 is mounted on the lower base plate 106 through the first servo motor mounting plate 111 and is located at one end of the first ball screw 110. The output shaft of the first servo motor 101 is connected to the first ball screw 110 through the first coupling 102.

[0019] The upper slide block mechanism 2 is identical to the lower slide block mechanism 1 except that it does not include the first servo motor and the first ball screw and their mounting structure. It includes an upper base plate, two upper slide rail pads, two upper slide rails, upper sliders, and an upper support plate, all of which are provided on the lower surface of the upper base plate. The two upper slide rail pads correspond one-to-one with the two lower slide rail pads. Each lower slide rail pad has an upper slide rail on its lower surface. Two upper sliders are provided on each upper slide rail. The upper support plate is provided on the four upper sliders.

[0020] The lifting mechanism includes a vertically arranged back plate 202, a second ball screw 208 vertically and rotatably mounted on the back plate 202, a movable stage 205 mounted on the nut of the second ball screw 208, guide rods 206 mounted on both sides of the second ball screw 208 along the horizontal movement direction, and a drive motor 201. The upper and lower ends of the back plate 202 are respectively mounted on an upper support plate and a lower support plate 104. The two guide rods 206 are vertically arranged and symmetrically arranged relative to the second ball screw 208. Each guide rod 206 is fixed at both ends to the back plate 202 by a shaft support 204. The movable stage 205 is slidably mounted on the guide rod 206. When the second ball screw 208 drives the movable stage 205 to move, the movable stage 205 slides relative to the guide rod 206, which plays a guiding role. The drive motor 210 is mounted on the back plate 202 by a drive motor mounting plate 209. The drive motor 210 is connected to the second ball screw 208 by a second coupling 203.

[0021] The rotary mechanism includes a first support cylinder 301 vertically arranged, a first mounting plate 302 arranged on the first support cylinder 301, a first ring gear 303 rotatably arranged on the first mounting plate 302, a first support plate 304 arranged on the first ring gear 303, and a magnetic chuck 305 arranged on the first support plate 304. The lower end of the first support cylinder 301 is supported on the moving stage 205. A rotary bearing 311 is arranged on the upper surface of the first mounting plate 302 at its outer edge. The first ring gear 303 is disposed in the rotary bearing 311 and... It can rotate relative to the rotary bearing 311. The first support plate 304 is disposed on the first ring gear 303. The magnetic chuck 305 is disposed on the first support plate 304. A through hole is provided in the middle of the magnetic chuck 305. A copper sleeve 307 is disposed in the through hole. The upper end of the copper sleeve 307 is aligned with the upper surface of the magnetic chuck 305. The lower end of the copper sleeve 307 extends from the lower surface of the magnetic chuck 305. The rotary mechanism also includes a hydraulic cylinder 306. The cylinder body of the hydraulic cylinder 306 is disposed in the copper sleeve 307. The piston rod of the hydraulic cylinder 306 extends downward. The rotary mechanism also includes a mounting cylinder 308, which is open upwards. The upper end of the mounting cylinder 308 is mounted on the first support plate 304. The lower end of the copper sleeve 307 is inserted into the mounting cylinder 308. The piston rod of the hydraulic cylinder 306 extends from the lower end of the mounting cylinder 308. A limiting cylinder 309 is provided at the lower end of the mounting cylinder 308, and the piston rod is inserted into the limiting cylinder 309. The end effector is attached to the upper surface of the magnetic chuck 305. During the operation of the end effector, there will be slight vibrations. The extension and retraction of the hydraulic cylinder 306 can absorb some of the vibrations, thus providing a buffering effect.

[0022] The rotary mechanism also includes a first rotary motor 310, which is fixed to the lower surface of the first mounting plate 302. A first rotary gear is provided on the output shaft of the first rotary motor 310. The first ring gear 303 is an internal gear. The first rotary gear meshes with the first ring gear 303. By controlling the first rotary motor 310, the rotation of the end effector can be realized.

[0023] The end effector includes an adsorption plate 401 adsorbed on a magnetic chuck 305, a second support cylinder 402 disposed on the adsorption plate 401, a third support cylinder 403 rotatably supported on the second support cylinder 402, a support base 404 movably supported on the third support cylinder 403, a first linkage arm 407, a second linkage arm 408, a third linkage arm 409, a gripper mounting base 411, and a gripper 410. A lifting screw 405 is disposed inside the support base 404, the upper end of which is fixed to the lower surface of the top of the support base 404. A lifting nut 406 is disposed on the lifting screw 405, and the lifting nut 406 is threadedly engaged with the lifting screw 405. The lifting nut 406 is rotatably disposed inside the third support cylinder 403 and cannot move up or down relative to the third support cylinder 403. Therefore, when the lifting nut 406 rotates, the lifting screw 405 can move up and down, thereby driving the support base 404 to move up and down.

[0024] The lower end of the first linkage arm 407 is hinged to the support base 404, and the hinge axis between the first linkage arm 407 and the support base 404 is horizontally arranged. The upper end of the first linkage arm 407 is hinged to the lower end of the second linkage arm 408, and the hinge axis between the first linkage arm 407 and the second linkage arm 408 is parallel to the hinge axis between the first linkage arm 407 and the support base 404. One end of the third linkage arm 409 is hinged to the upper end of the second linkage arm 408, and the hinge axis between the third linkage arm 409 and the second linkage arm 408 is parallel to the hinge axis between the first linkage arm 407 and the support base 404. A gripper mounting base 411 is rotatably provided at the other end of the third linkage arm 409, and a gripper 410 is provided on the gripper mounting base 411. The gripper mounting base 411 is rotatable relative to the third linkage arm 409, and the axis of rotation is parallel to the extension direction of the third linkage arm 409. All linkage arms are driven by a motor and gear combination.

[0025] The working steps of the robotic arm of this invention are as follows: 1) The horizontal moving mechanism will move the actuator to the required position based on the location of the medicine to be retrieved; 2) The lifting mechanism moves the actuator to the predetermined height; 3) The rotary mechanism drives the actuator to rotate to a predetermined angle. When viewed from above, the gripper and the line where the medicine to be picked up are located are perpendicular to the direction of movement of the horizontal moving mechanism. 4) The movement of the first linkage arm, the second linkage arm, and the third linkage arm enables the gripper to move and grip the medicine, while the support base can move up and down as needed. 5) The grippers hold the medicine and place it in the predetermined position.

[0026] Example 2 This embodiment is a dynamic analysis of the end effector, specifically including the following steps: Step 1: Select any point on the i-th link. The velocity of this point is expressed as follows: (1), Let r be the fixed position vector of any point in the coordinate system of the i-th link itself, and let r be the position vector of any point in the global coordinate system of the end effector, which can be expressed as: n=4, which is the total number of joints or links; i=1, 2, 3, 4, the first link is the first linkage arm 407, the second link is the second linkage arm 408, the third link is the third linkage arm 409, and the fourth link is the gripper mounting base 411. Let be the homogeneous transformation matrix from the coordinate system of support 404 to the coordinate system of the i-th link; Let be the joint variable of the j-th joint, where is the angle for a rotary joint and the displacement for a translational joint; Joint velocity; Since there are a total of 4 links, They are respectively , This is the homogeneous transformation matrix between the support and the first link. This is the homogeneous transformation matrix between the support and the second link. This is the homogeneous transformation matrix between the support and the third link. Let be the homogeneous transformation matrix between the support and the fourth link, and , , , , , , , It is the homogeneous transformation matrix between the support and the first link. It is the homogeneous transformation matrix between the first link and the second link. It is the homogeneous transformation matrix between the second and third links. It is the homogeneous transformation matrix between the 3rd and 4th links. Based on the specific structure of the end effector in Embodiment 1, we can obtain: , in, Let be the translation of the coordinate system of the first link relative to the coordinate system of the support in the z-axis direction. , in, Let be the rotation angle of the second link relative to the first link. The length of the first link. , in, Let be the rotation angle of the third link relative to the second link. The length of the second link. , in, Let be the rotation angle of the fourth link relative to the third link. The length of the third link; Step 2: Express formula (1) using evidence, and we get: (2); Step 3: Kinetic energy of the i-th link for: (3), in, For point The mass of the micro-element, , where is the inertia tensor of the i-th link; Step 4: Since there are motors between the various links, these motors also provide some kinetic energy to the links. Therefore, the above equation should be: (4), in, Let be the inertia of the motor at the j-th shutdown point; Step 5: Calculate the total potential energy of the end effector using formula (5): (5), in, Let gravitational acceleration vector be , which can be represented as , It is the acceleration due to gravity. Let the mass of the i-th link be denoted as . Step 6: Obtain the Lagrange function according to formulas (4) and (5): L=KP (6), Step 7: Substitute formula (6) into the Lagrange equation to obtain the dynamic equation of the end effector: (7), in, For the action in the The first joint The generalized force of a link.

[0027] The basic principles, main features, and advantages of the present invention have been shown and described. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention, and various changes and modifications can be made without departing from the spirit and scope of the invention. All such changes and modifications fall within the scope of the claimed invention. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A robotic arm for grasping pharmaceuticals, characterized in that, It includes a horizontal motion mechanism, a lifting mechanism, a rotary mechanism, and an end effector. The horizontal motion mechanism is used to drive the end effector to move horizontally along the direction of the medicine shelf. The lifting mechanism is used to drive the end effector to move up and down. The rotary mechanism is used to drive the end effector to rotate. The end effector is used to grip medicine. The horizontal moving mechanism includes an upper sliding block mechanism and a lower sliding block mechanism. The lower sliding block mechanism includes a lower base plate, a first coupling, a bearing seat, two lower sliding rail pads, two lower sliding rails, a lower sliding block, a lower bearing plate, a first servo motor, and a first ball screw. The lower base plate extends along the moving direction of the end effector. The two lower sliding rail pads are arranged parallel to each other on the lower base plate and extend along the moving direction of the end effector. The two lower sliding rails are respectively arranged on the two lower sliding rail pads. The lower sliding rails and the lower sliding rail pads have the same extending direction and the same length. The two ends of the lower sliding rails are aligned with the two ends of the corresponding lower sliding rail pads. Two lower sliding blocks are arranged on each lower sliding rail. The lower bearing plate is fixed on four lower sliding blocks. The first ball screw is located between the two lower sliding rails and parallel to the lower sliding rails. The two ends of the first ball screw are respectively supported on two bearing seats by bearings. The two bearing seats are fixed on the lower base plate. The first ball screw is mounted on the lower base plate by a first servo motor mounting plate and is located at one end of the first ball screw. The output shaft of the first servo motor is connected to the first ball screw through the first coupling.

2. The drug-grabbing robotic arm according to claim 1, characterized in that, The upper slide block mechanism includes an upper base plate, two upper slide rail pads, two upper slide rails, an upper slide block, and an upper support plate, all disposed on the lower surface of the upper base plate. The two upper slide rail pads correspond one-to-one with the two lower slide rail pads. Each lower slide rail pad has an upper slide rail on its lower surface. Each upper slide rail has two upper slide blocks. The upper support plate is disposed on the four upper slide blocks.

3. The drug-grabbing robotic arm according to claim 2, characterized in that, The lifting mechanism includes a vertically arranged back plate, a second ball screw vertically and rotatably mounted on the back plate, a movable stage mounted on the nut of the second ball screw, guide rods on both sides of the second ball screw along the horizontal movement direction, and a drive motor. The upper and lower ends of the back plate are respectively mounted on an upper bearing plate and a lower bearing plate. The two guide rods are vertically arranged and symmetrically arranged relative to the second ball screw. The two ends of each guide rod are fixed to the back plate by shaft support brackets. The movable stage is slidably mounted on the guide rod. When the second ball screw drives the movable stage to move, the movable stage slides relative to the guide rod. The drive motor is mounted on the back plate through a drive motor mounting plate and is connected to the second ball screw through a second coupling.

4. A drug-grabbing robotic arm according to claim 3, characterized in that, The rotary mechanism includes a first support cylinder vertically arranged, a first mounting plate arranged on the first support cylinder, a first ring gear rotatably arranged on the first mounting plate, a first support plate arranged on the first ring gear, and a magnetic chuck arranged on the first support plate. The lower end of the first support cylinder is supported on a moving platform. A rotary bearing is arranged on the upper surface of the first mounting cylinder at the outer edge. The first ring gear is arranged inside the rotary bearing and can rotate relative to the rotary bearing. The first support plate is arranged on the first ring gear. The magnetic chuck is arranged on the first support plate. A through hole is arranged in the middle of the magnetic chuck. A copper sleeve is arranged in the through hole. The upper end of the copper sleeve is aligned with the upper surface of the magnetic chuck, and the lower end of the copper sleeve extends from the lower surface of the magnetic chuck. The rotary mechanism also includes a hydraulic cylinder and a mounting cylinder. The cylinder body of the hydraulic cylinder is disposed inside a copper sleeve, the piston rod of the hydraulic cylinder extends downward, the mounting cylinder opens upward, the upper end of the mounting cylinder is disposed on a first support plate, the lower end of the copper sleeve is inserted into the mounting cylinder, the piston rod of the hydraulic cylinder protrudes from the lower end of the mounting cylinder, a limit cylinder is provided at the lower end of the mounting cylinder, and the piston rod is inserted into the limit cylinder.

5. A drug-grabbing robotic arm according to claim 4, characterized in that, The rotary mechanism further includes a first rotary motor, which is fixed to the lower surface of the first mounting plate. A first rotary gear is provided on the output shaft of the first rotary motor. The first ring gear is an internal gear, and the first rotary gear meshes with the first ring gear.

6. A drug-grabbing robotic arm according to claim 5, characterized in that, The end effector includes an adsorption plate adsorbed on a magnetic chuck, a second support cylinder disposed on the adsorption plate, a third support cylinder rotatably supported on the second support cylinder, a support base movably supported on the third support cylinder, a first linkage arm, a second linkage arm, a third linkage arm, a gripper mounting base, and grippers. A lifting screw is disposed within the support base, the upper end of which is fixed to the lower surface of the top of the support base. A lifting nut is disposed on the lifting screw, the lifting nut being threadedly engaged with the lifting screw. The lifting nut is rotatably disposed within the third support cylinder and cannot move up or down relative to the third support cylinder.

7. A drug-grabbing robotic arm according to claim 6, characterized in that, The lower end of the first linkage arm is hinged to the support base. The hinge axis between the first linkage arm and the support base is horizontally arranged. The upper end of the first linkage arm is hinged to the lower end of the second linkage arm. The hinge axis between the first linkage arm and the second linkage arm is parallel to the hinge axis between the first linkage arm and the support base. One end of the third linkage arm is hinged to the upper end of the second linkage arm. The hinge axis between the third linkage arm and the second linkage arm is parallel to the hinge axis between the first linkage arm and the support base. A gripper mounting base is rotatably provided at the other end of the third linkage arm. A gripper is provided on the gripper mounting base. The gripper mounting base is rotatable relative to the third linkage arm, and the axis of rotation is parallel to the extension direction of the third linkage arm.

8. A drug-grabbing robotic arm according to claim 7, characterized in that, The following steps are used to perform a dynamic analysis of the end effector: Step 1: Select any point on the i-th link. The velocity of this point is expressed as follows: （1）， Let r be the fixed position vector of any point in the coordinate system of the i-th link itself, and let r be the position vector of any point in the global coordinate system of the end effector. i = 1, 2, 3, 4, the first link is the first linkage arm, the second link is the second linkage arm, the third link is the third linkage arm, and the fourth link is the gripper mounting base; Let be the homogeneous transformation matrix from the coordinate system of the support to the coordinate system of the i-th link; Let j be the joint variable of the j-th joint; Joint velocity; Step 2: Represent formula (1) using a matrix, and obtain: （2）； Step 3: Kinetic energy of the i-th link for: （3）， in, For point The mass of the micro-element, , where is the inertia tensor of the i-th link; Step 4: Since there are motors between the various links, these motors also provide some kinetic energy to the links. Therefore, the above equation should be: （4）， in, Let be the inertia of the motor at the j-th shutdown point; Step 5: Calculate the total potential energy of the end effector using formula (5): （5）， in, Let gravitational acceleration vector be , which can be represented as , It is the acceleration due to gravity. Let the mass of the i-th link be denoted as . Step 6: Obtain the Lagrange function according to formulas (4) and (5): L=KP (6), Step 7: Substitute formula (6) into the Lagrange equation to obtain the dynamic equation of the end effector: （7）， in, For the action in the At the first joint The generalized force of a link.

9. A drug-grabbing robotic arm according to claim 8, characterized in that, They are respectively , This is the homogeneous transformation matrix between the support and the first link. This is the homogeneous transformation matrix between the support and the second link. This is the homogeneous transformation matrix between the support and the third link. Let be the homogeneous transformation matrix between the support and the fourth link, and , , , , , , , It is the homogeneous transformation matrix between the support and the first link. It is the homogeneous transformation matrix between the first link and the second link. It is the homogeneous transformation matrix between the second and third links. It is the homogeneous transformation matrix between the 3rd and 4th links, and: , in, Let be the translation of the coordinate system of the first link relative to the coordinate system of the support in the z-axis direction. , in, Let be the rotation angle of the second link relative to the first link. The length of the first link. , in, Let be the rotation angle of the third link relative to the second link. The length of the second link. , in, Let be the rotation angle of the fourth link relative to the third link. This is the length of the third link.

10. A dynamic analysis method for an end effector, characterized in that, The end effector includes a vertically movable support base, a first linkage arm, a second linkage arm, a third linkage arm, a gripper mounting base, and grippers. The lower end of the first linkage arm is hinged to the support base, and the hinge axis between the first linkage arm and the support base is horizontally arranged. The upper end of the first linkage arm is hinged to the lower end of the second linkage arm, and the hinge axis between the first and second linkage arms is parallel to the hinge axis between the first linkage arm and the support base. One end of the third linkage arm is hinged to the upper end of the second linkage arm, and the hinge axis between the third and second linkage arms is parallel to the hinge axis between the first linkage arm and the support base. A gripper mounting base is rotatably mounted on the other end of the third linkage arm, and grippers are mounted on the gripper mounting base. The dynamic analysis method includes the following steps: Step 1: Select any point on the i-th link. The velocity of this point is expressed as follows: （1）， Let r be the fixed position vector of any point in the coordinate system of the i-th link itself, and let r be the position vector of any point in the global coordinate system of the end effector. i = 1, 2, 3, 4, the first link is the first linkage arm, the second link is the second linkage arm, the third link is the third linkage arm, and the fourth link is the gripper mounting base; Let be the homogeneous transformation matrix from the coordinate system of the support to the coordinate system of the i-th link; Let j be the joint variable of the j-th joint; Joint velocity; Step 2: Represent formula (1) using a matrix, and obtain: （2）； Step 3: Kinetic energy of the i-th link for: （3）， in, For point The mass of the micro-element, , where is the inertia tensor of the i-th link; Step 4: Since there are motors between the various links, these motors also provide some kinetic energy to the links. Therefore, the above equation should be: （4）， in, Let be the inertia of the motor at the j-th shutdown point; Step 5: Calculate the total potential energy of the end effector using formula (5): （5）， in, Let gravitational acceleration vector be , which can be represented as , It is the acceleration due to gravity. Let the mass of the i-th link be denoted as . Step 6: Obtain the Lagrange function according to formulas (4) and (5): L=KP (6), Step 7: Substitute formula (6) into the Lagrange equation to obtain the dynamic equation of the end effector: （7）， in, For the action in the At the first joint The generalized force of a link.

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