Hybrid robot kinematics analytical method

Abstract

The application discloses a hybrid robot kinematics analysis method, which is applied to a hybrid robot and comprises the following steps: acquiring the position coordinates of key points in parallel structure parts in an upper motion platform and a lower motion platform based on a base coordinate system by using a geometric analysis method; acquiring the rotation angles of upper universal joints and lower universal joints; establishing DH models of series structure parts in the upper motion platform and the lower motion platform based on the position coordinates and the rotation angles; determining DH parameter tables of upper models and lower models based on the DH models; solving the pose of a terminal sleeve and a puncture needle based on the DH parameter tables, and obtaining a conversion matrix of any point on the puncture needle relative to the base coordinate system. The application can realize the technical effect that kinematics analysis of the hybrid robot is more efficient, and thus solves the problem that the kinematics analysis method in the prior art is not applicable to kinematics analysis of the hybrid robot.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of surgical robots, in particular to a hybrid robot kinematics analysis method. BACKGROUND

[0002] For kinematics analysis of a puncture surgical robot, a geometric analysis method or a DH model method is generally used for analysis. However, for a hybrid structure, that is, a robot containing both parallel structure and multiple serial structures, the use of a simple geometric analysis method will significantly increase the complexity, and the DH modeling method cannot be directly applied. SUMMARY

[0003] The main purpose of the present application is to provide a hybrid robot kinematics analysis method to solve the problem that the kinematics analysis method in the related art is not applicable to kinematics analysis of a hybrid robot.

[0004] In order to achieve the above-mentioned purpose, the present application provides a hybrid robot kinematics analysis method applied to a hybrid robot, wherein the hybrid robot comprises an upper motion platform and a lower motion platform, the upper motion platform comprises two first linear motion members, a first horizontal support, an upper universal joint and a sliding block, the two first linear motion members are connected in parallel and then connected in series with the first horizontal support, the upper universal joint and the sliding block in sequence;

[0005] The lower motion platform comprises two second linear motion members, a second horizontal support and a lower universal joint, the two second linear motion members are connected in parallel and then connected in series with the second horizontal support, the lower universal joint and an end support in sequence, and the upper motion platform and the lower motion platform are connected in parallel through the sliding block and a guide rail on the end support;

[0006] The kinematics analysis method comprises:

[0007] The geometric analysis method is used to obtain position coordinates of key points in the parallel structure part of the upper motion platform and the lower motion platform based on a base coordinate system;

[0008] The rotation angles of the upper universal joint and the lower universal joint are obtained;

[0009] The DH model of the serial structure part of the upper motion platform and the lower motion platform is established based on the position coordinates and the rotation angles;

[0010] The DH parameter table of the upper model and the lower model is determined based on the DH model;

[0011] The pose of the end sleeve and the puncture needle is solved based on the DH parameter table, and the conversion matrix of any point on the puncture needle relative to the base coordinate system is obtained.

[0012] Further, the first ends of the two first linear motion members are hinged to the mounting platform, and the second ends thereof are hinged to the first horizontal support;

[0013] The second ends of the two second linear motion members are hinged to the mounting platform, and the second ends thereof are hinged to the second horizontal support;

[0014] The center point of the hinge points of the second ends of the two first linear motion members is O 2+ , and the center point of the hinge points of the second ends of the two second linear motion members is O 2- ;

[0015] The position coordinates of the key points in the upper motion platform and the lower motion platform are obtained, comprising:

[0016] The position coordinates (x 2+ , y 2+ , z 2+ ) of the O 2+ and the position coordinates (x 2- , y 2- , z 2- ) of the O 2- are obtained.

[0017] Further, the base coordinate system is a coordinate system established with the intersection point of the hinge points of the first ends of the two first linear motion members and the hinge points of the first ends of the two second linear motion members as the origin.

[0018] Further, the position coordinates of the key points in the upper motion platform and the lower motion platform are obtained based on the base coordinate system by using a geometric analysis method, specifically:

[0019] The distance between the hinge points of the first end and the second end of the first linear motion member is corrected;

[0020] The distance between the hinge points of the first end and the second end of the second linear motion member is corrected;

[0021] The parallel structure in the upper motion platform and the lower motion platform is simplified into a trapezoidal configuration based on the corrected results;

[0022] Based on the trapezoidal configuration, the position coordinates of the O 2+ and the O 2- are obtained by using a geometric analysis method.

[0023] Further, the rotation angles of the upper gimbal and the lower gimbal are obtained, specifically:

[0024] The rear end and the front end of the upper layer universal joint and the lower layer universal joint have a rotation axis respectively, the rotation angle of the rear end and the front end of the upper layer universal joint is set as θ wb+ and θ wf+ respectively, the rotation angle of the rear end and the front end of the lower layer universal joint is set as θ wb- and θ wf- respectively.

[0025] θ wb+ = θ wb- , θ wf+ = θ wf- .

[0026]

[0027]

[0028] Δx2=x 2+ -x 2- .

[0029] Δy2=y 2+ -y 2- .

[0030] Further, based on the DH parameter table, the position and posture of the end sleeve and the puncture needle are solved, and the conversion matrix of any point on the puncture needle relative to the base coordinate system is obtained, specifically:

[0031] The position and posture of the end sleeve and the puncture needle are expressed by a 4*4 homogeneous transformation matrix:

[0032]

[0033] The homogeneous transformation matrix of the end sleeve relative to the base coordinate system is:

[0034] 0 T3= 0 A1* 1 A2* 2 A3.

[0035] Wherein, for the ith joint, the transformation relationship between the ith connecting rod and the ith coordinate system is as follows:

[0036]

[0037] Suppose that the position coordinates of any point on the puncture needle fixedly connected with the end sleeve relative to O 3- are (t x , t y , t z ), the homogeneous transformation matrix of the point relative to O3 is:

[0038]

[0039] The conversion matrix T of any point on the puncture needle relative to the base coordinate system is:

[0040] T = T3T2T1 0 T3T tool

[0041] Further, the first horizontal support and the second horizontal support are constrained to be able to only translate in the XOY plane.

[0042] According to another aspect of the present application, an electronic device is provided, comprising:

[0043] a memory, the memory storing execution instructions; and

[0044] a processor, the processor executing the execution instructions stored in the memory, so that the processor executes the hybrid robot kinematics analysis method described above.

[0045] According to another aspect of the present application, a readable storage medium is provided, the readable storage medium storing execution instructions, the execution instructions being executed by a processor to implement the hybrid robot kinematics analysis method described above.

[0046] According to another aspect of the present application, a robot system is provided, comprising: the readable storage medium described above, the robot system being configured to perform kinematics solving based on the execution instructions stored in the readable storage medium.

[0047] In the embodiment of the present application, the hybrid robot is provided, the hybrid robot comprises an upper motion platform and a lower motion platform, the upper motion platform comprises two first linear motion members, a first horizontal support, an upper universal joint and a sliding block, the two first linear motion members are connected in parallel and then connected in series with the first horizontal support, the upper universal joint and the sliding block in sequence; the lower motion platform comprises two second linear motion members, a second horizontal support and a lower universal joint, the two second linear motion members are connected in parallel and then connected in series with the second horizontal support, the lower universal joint and a terminal support in sequence, and the upper motion platform and the lower motion platform are connected in parallel through the sliding block and the guide rail on the terminal support; the kinematics analysis method applied to the hybrid robot comprises the following steps: establishing a base coordinate system, obtaining the position coordinates of key points in the parallel structure part of the upper motion platform and the lower motion platform by using a geometric analysis method based on the base coordinate system; obtaining the rotation angles of the upper universal joint and the lower universal joint; establishing a DH model of the series structure part of the upper motion platform and the lower motion platform based on the position coordinates and the rotation angles; determining a DH parameter table of the upper model and the lower model based on the DH model; solving the pose of the terminal sleeve and the puncture needle based on the DH parameter table, and obtaining the conversion matrix of any point on the puncture needle relative to the base coordinate system, so as to achieve the technical effect that the kinematics analysis of the hybrid robot can be more efficiently performed, and the problem that the kinematics analysis method in the related art is not suitable for the kinematics analysis of the hybrid robot is solved. BRIEF DESCRIPTION OF DRAWINGS

[0048] The accompanying drawings, which form a part of this application, are included to provide a further understanding of the application and are incorporated in and constitute a part of this application. The embodiments illustrated in the drawings of the application in which:

[0049] Figure 1 is a structural schematic diagram according to the embodiment of the present application;

[0050] Figure 2 is a structural schematic diagram for limiting parallel members according to the embodiment of the present application;

[0051] Figure 3 is an exploded structural schematic diagram of a motor according to the embodiment of the present application;

[0052] Figure 4 is an assembly structural schematic diagram of a motor according to the embodiment of the present application;

[0053] Figure 5 is a sectional structural schematic diagram of a motor according to the embodiment of the present application;

[0054] Figure 6 is a schematic view of an exploded structure of the end support according to an embodiment of the present application;

[0055] Figure 7 is a schematic view of a side structure of the end support according to an embodiment of the present application;

[0056] Figure 8 is a schematic view of an exploded structure of the end support according to an embodiment of the present application; Figure 7 is a schematic view of a sectional structure of B-B;

[0057] Figure 9 is a schematic view of an assembled structure of the end support according to an embodiment of the present application;

[0058] Figure 10 is a simplified schematic view of the lower motion platform according to an embodiment of the present application;

[0059] Figure 11 is a schematic view of the DH model according to an embodiment of the present application.

[0060] wherein 1 is a mounting platform, 2 is a motion platform, 21 is a limiting parallel member, 211 is a sliding seat, 212 is a mounting hole, 213 is a guide piece, 214 is a second guide rail, 215 is a linear bearing, 22 is a linear motion member, 221 is a connecting arm, 222 is a motor base, 223 is a driving motor, 224 is a screw nut, 225 is a screw rod, 226 is a third guide rail, 227 is a motor housing, 228 is a guide rail slider, 23 is a connecting piece, 24 is a universal joint, 3 is an end support, 31 is a puncture connecting plate, 311 is a connecting column, 312 is a fixed column, 32 is an end connecting piece, 321 is a connecting hole, 322 is a first buckling groove, 323 is a first fixing groove, 33 is an end detachable piece, 331 is a second fixing groove, 332 is a second buckling groove, 333 is a handle, 34 is a puncture sleeve, 4 is a first guide rail, and 5 is a slider. DETAILED DESCRIPTION

[0061] In order to enable persons skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by persons skilled in the art without creative work should fall within the protection scope of the present application.

[0062] It should be noted that the terms “first”, “second”, and the like in the specification and claims of the present application and the above-described drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so as to describe the embodiments of the present application.

[0063] In the present application, the terms "upper", "lower", "inner", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not intended to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0064] In addition to indicating the orientation or positional relationship, the above-mentioned partial terms can also be used to represent other meanings, for example, the term "upper" can also be used to represent a certain dependent relationship or connection relationship in some cases. For those skilled in the art, the specific meaning of these terms in the present application can be understood according to the specific circumstances.

[0065] In addition, the terms "provided", "provided with", "connected", "fixed", etc. should be broadly understood. For example, "connected" can be fixed connection, detachable connection, or integral structure; can be mechanical connection, or electrical connection; can be direct connection, or indirect connection through an intermediate medium, or internal communication between two devices, elements or components. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0066] In addition, the meaning of the term "a plurality of" should be two or more.

[0067] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0068] Embodiment 1:

[0069] Due to the complexity of the puncture operation, the end effector needs to have multiple degrees of freedom. In the related art, multiple motion platforms are stacked to achieve multiple degrees of freedom. For example, two large motion platforms are stacked in the related art, and each large motion platform is composed of two stacked sub-motion platforms, and the output directions of the sub-motion platforms are perpendicular. Although this type of end effector can meet the demand for degrees of freedom, it will cause the longitudinal volume of the end effector to increase, affecting the operation accuracy.

[0070] To solve the above technical problems, the present embodiment provides a miniaturized hybrid robot, which comprises: a mounting platform 1, a motion platform 2 and an end support 3; wherein,

[0071] The motion platform 2 is arranged on the mounting platform 1, and the motion platform 2 is arranged in two and distributed vertically; the motion platform 2 comprises two linear motion members 22 arranged in the horizontal direction, a connecting member 23, a universal joint 24 and a limiting parallel member 21;

[0072] Two linear motion members 22 are arranged on the two sides of the mounting platform 1, the first ends of the two linear motion members 22 are hingedly connected with the mounting platform 1, the second ends of the two linear motion members 22 are hingedly connected with the two ends of the connecting member 23, the universal joint 24 is hingedly connected with the connecting member 23;

[0073] A first connecting line is formed between the hingedly connected points of the two linear motion members 22 and the mounting platform 1, a second connecting line is formed between the hingedly connected points of the two linear motion members 22 and the connecting member 23, the first connecting line and the second connecting line are parallel, and the linear motion directions of the two linear motion members 22 are not parallel;

[0074] One end of the parallel member 21 is connected with the mounting platform 1, and the other end is connected with the connecting member 23, so that the second connecting line can be kept parallel to the first connecting line during the movement;

[0075] The end support 3 is provided with a first guide rail 4 parallel to the needle insertion direction, the universal joint 24 in one of the motion platforms 2 is slidingly connected with the first guide rail 4 through a sliding block 5, and the universal joint 24 in the other motion platform 2 is connected with the end support 3.

[0076] In the embodiment, the electric end effector mainly comprises a mounting platform 1, a motion platform 2 and an end support 3. The mounting platform 1 is a fixed member, which serves as a mounting base of the motion platform 2 and as a structure connected with the mechanical arm of the puncture robot. The structure of the mounting platform 1 only needs to meet the installation of the two motion platforms 2, and in an embodiment, the mounting platform 1 is in a frame type or a plate type, and preferably in a frame type, which can reduce the weight while ensuring the structural strength. The motion platform 2 serves as a motion member in the end support 3 effector, which is installed on the mounting platform 1, and the end support 3 serves as an operated member and is connected with the output end of the motion platform 2, so that the end support 3 is driven by the motion platform 2 to move in multiple degrees of freedom.

[0077] In order to keep the end support 3 in a posture, the two ends of the end support 3 need to be connected with the motion platforms 2. Therefore, the motion platforms 2 in the embodiment are arranged in an upper and lower distribution. The two motion platforms 2 can be simultaneously installed on the upper side or the lower side of the mounting platform 1, or the two motion platforms 2 can be respectively installed on the upper and lower sides of the mounting platform 1. Preferably, the two motion platforms 2 are installed on the upper and lower sides of the mounting platform 1, which can avoid the mutual influence between the two motion platforms 2. The two motion platforms 2 arranged in an upper and lower distribution determine two connection points with the end support 3, so that the end support 3 can be kept in a posture during the movement.

[0078] In order to reduce the longitudinal volume of the end support 3 effector, the two motion platforms 2 are arranged in an upper and lower distribution, and the two motion platforms 2 are connected with the end support 3 through the connecting member 23, so that the end support 3 can be kept in a posture during the movement. Figure 1As shown, two linear motion members 22 in the motion platform 2 in the embodiment are arranged in the horizontal direction and are respectively installed on the two sides of the mounting platform 1. The longitudinal volume is obviously reduced relative to the stacking mode of the four sub-motion platforms. The linear motion member 22 is a structure capable of generating linear motion, which can be composed of a motor or a cylinder capable of realizing linear motion.

[0079] To realize the multi-degree-of-freedom motion of the end support 3, the motion platform 2 in the embodiment can be composed of a trapezoidal motion member. Specifically, as shown in the figure, the first end of the linear motion member 22 is hinged to the mounting platform 1. For one motion platform 2, the connecting line between the hinge points of the two linear motion members 22 and the mounting platform 1 is the bottom side of the trapezoid, and the bottom side is fixed. The linear motion directions of the two linear motion members 22 are not parallel, so the linear motion paths of the two linear motion members 22 are the oblique sides of the trapezoid. The second ends of the two linear motion members 22 are hinged to the two ends of the connecting member 23, so the connecting line between the two hinge points is the top side of the trapezoid. The top side is a structure connected to the output end of the linear motion member 22, which needs to move under the action of the linear motion member 22, and the position change between the top sides of the upper and lower motion platforms 2 makes the end support 3 adjust the different postures. Figure 1

[0080] To stabilize the structure, the trapezoidal motion member needs to be constrained so that the bottom side and the top side always remain parallel. Therefore, a limiting parallel member 21 is additionally arranged in the embodiment. One end of the limiting parallel member 21 is connected to the mounting platform 1, and the other end is connected to the connecting member 23, so that the connecting line two remains parallel to the connecting line one during the motion. The motion of the top side can be decomposed into linear motion along the X-axis and Y-axis in the horizontal plane, so the limiting parallel member 21 functions to prevent the top side from tilting during the motion of the top side, so that it can remain parallel to the bottom side. Therefore, in one embodiment, the limiting parallel member 21 can be a composite structure capable of realizing linear motion along the X-axis and Y-axis, which can constrain the position of the top side after being connected to the top side, so that it can also only move linearly along the X-axis and Y-axis, and finally realize the parallel constraint of the top side.

[0081] When the end support 3 adjusts some postures, the distance between the two universal joints 24 on the end support 3 needs to be changed. Therefore, a first guide rail 4 is arranged on the end support 3 in the embodiment, and the first guide rail 4 is parallel to the needle insertion direction. The universal joint 24 of one motion platform 2 is connected to the first guide rail 4 through a sliding block 5, and the universal joint 24 of the other motion platform 2 is directly connected to the end support 3. When the posture of the end support 3 changes, the distance between the two universal joints 24 changes, and the universal joint 24 connected to the first guide rail 4 through the sliding block 5 slides along the guide rail, thereby realizing the adjustment of the posture of the end support 3. ​

[0082] The embodiment is characterized in that two motion platforms 2 are arranged above and below, two linear motion members 22 in each motion platform 2 are arranged horizontally, and the two linear motion members 22 in each motion platform 2 form a trapezoidal motion member after being connected with the mounting platform 1 and the connecting member 23, and the parallelism of the two parallel sides of the motion member is maintained by the limiting parallel member 21 during the motion, so that the purpose of realizing the precise multi-degree-of-freedom operation of the end support 3 while reducing the longitudinal volume of the end support 3 executor is achieved, thereby solving the problem of the large longitudinal volume of the multi-degree-of-freedom end support 3 executor in the related art, which affects the operation precision.

[0083] In one specific embodiment of the limiting parallel member 21, as shown in Figure 1 and Figure 2 the limiting parallel member 21 includes a second guide rail 214, a sliding seat 211, and a guide member 213.

[0084] The second guide rail 214 is arranged on the mounting platform 1 and extends along a first direction, the sliding seat 211 is slidingly arranged on the second guide rail 214, and the guide member 213 extends along a second direction and is slidingly arranged on the sliding seat 211, and the end of the guide member 213 is fixedly connected with the connecting member 23, the first direction is parallel to the connecting line II, and the first direction is perpendicular to the second direction.

[0085] In the embodiment, the second guide rail 214 is mounted at the front end of the mounting platform 1 (i.e., the end close to the end support 3) along the first direction, the sliding seat 211 is mounted on the second guide rail 214 and can slide along the first direction, and the guide member 213 is arranged along the second direction and is slidingly connected with the sliding seat 211, and the end of the guide member 213 close to the connecting member 23 is fixedly connected with the connecting member 23. When the two linear members of the motion platform 2 move forward synchronously from the zero position, the sliding seat 211 remains stationary, and the guide member 213 moves linearly forward with the connecting member 23, at this time, the sliding seat 211 serves as a guide structure for the guide member 213, and also serves as a guide structure for the connecting member 23. When the two linear members of the motion platform 2 move linearly at different amounts, the first end of the two linear motion members 22 rotates around the hinge point, and at the same time, the sliding seat 211 moves linearly along the first guide rail 4, and the guide member 213 moves linearly along the sliding seat 211 to constrain the connecting member 23 to move translationally.

[0086] In one embodiment, in order to facilitate the linear motion of the guide member 213 along the sliding seat 211, the sliding seat 211 is provided with a mounting hole 212 in the embodiment, a linear bearing 215 is arranged in the mounting hole 212, the guide member 213 is arranged as a guide optical axis, the guide optical axis is slidingly sleeved in the linear bearing 215, and the end of the guide optical axis is fixedly connected with the connecting member 23. The mounting hole 212 can be provided with two, and the corresponding guide optical axis is also provided with two, so as to improve the stability.

[0087] Since the linear motion direction of the linear motion member 22 is not parallel, and the connecting member 23 is the short side of the trapezoid, in order to enable the linear motion member 22 to smoothly drive the connecting member 23 to move, as shown in the figure, the linear motion member 22 in the embodiment includes a motor and a connecting arm 221, the motor is hinged to the mounting platform 1, the first end of the connecting arm 221 is hinged to the output end of the motor, and the second end is hinged to the connecting member 23. The output end of the connecting arm 221 and the motor forms an obtuse angle. Figure 1

[0088] The stability and accuracy of the output of the motor directly affect the performance of the end support 3. Therefore, in order to enable the motor to realize stable and accurate linear output, as shown in the figure, the motor in the embodiment includes a motor base 222, a motor housing 227, a driving motor 223, a lead screw 225, a lead screw nut 224, a third guide rail 226, and a guide rail slider 228. Figures 3 to 5

[0089] The motor base 222 is fixedly arranged at one end of the motor housing 227, the driving motor 223 is fixedly arranged in the motor base 222, the lead screw 225 is arranged in the motor housing 227 and is in transmission connection with the driving motor 223, the lead screw nut 224 is threadedly connected on the lead screw 225, and the lead screw nut 224 can move linearly with the rotation of the lead screw 225.

[0090] The third guide rail 226 is fixedly connected with the lead screw nut 224, the end of the third guide rail 226 extends out of the motor housing 227 and is connected with the connecting arm 221, the guide rail slider 228 is fixedly arranged in the motor housing 227 and is in sliding connection with the third guide rail 226, so as to limit the movement direction of the third guide rail 226.

[0091] In the embodiment, the motor housing 227 can limit the rotation freedom degree of the lead screw nut 224, so that the lead screw nut 224 can move linearly when the lead screw 225 rotates. In order to enable the lead screw 225 to rotate stably, bearings can be arranged between the two ends of the lead screw 225 and the motor housing 227. The motor base 222 is a structure for fixing the driving motor 223, and is arranged at the end of the motor housing 227 away from the connecting member 23. After the driving motor 223 is in transmission connection with the lead screw 225, the driving motor 223 drives the lead screw 225 to rotate, thereby driving the lead screw nut 224 to move linearly.

[0092] In order to enable the linear movement of the lead screw nut 224 to be stably output, in the embodiment, the third guide rail 226 and the guide rail slider 228 are cooperated to realize. The guide rail slider 228 is fixedly arranged in the motor housing 227, the third guide rail 226 is in sliding cooperation with the guide rail slider 228 while being fixedly connected with the lead screw nut 224, the guide rail slider 228 can guide the linear movement of the guide rail, so that the guide rail will not be deviated when performing long linear movement, thereby improving the stability and accuracy of the movement.​​

[0093] It can be understood that the lead screw in the embodiment can be a ball screw, or a threaded rod, or a trapezoidal screw 225, etc.

[0094] In order to facilitate detection of the displacement amount during movement, the motor in the embodiment further includes a position sensor, a detection end of the position sensor being connected to the lead screw nut 224 to detect the moving position of the lead screw nut 224.

[0095] In order to facilitate installation and disassembly of the end support 3, as shown in Figures 6 to 9 the end support 3 in the embodiment includes a puncture connecting plate 31, an end connecting piece 33, an end detachable piece 33, and a puncture sleeve 34.

[0096] The first side of the puncture connecting plate 31 is provided with a first guide rail 4, one of the universal joints 24 in one of the movement platforms 2 is connected to the first guide rail 4 through a sliding block 5, and the universal joint 24 in the other movement platform 2 is connected to the puncture connecting plate 31.

[0097] The end connecting piece 33 is detachably fixed to the second side of the puncture connecting plate 31, the end detachable piece 33 is detachably fixed to the end connecting piece 33, and the puncture sleeve 34 is detachably fixed to the end detachable piece 33.

[0098] In the embodiment, the puncture connecting plate 31 and the end connecting piece 33 are approximately provided in an L shape, and the first guide rail 4 is arranged on the vertical surface of the puncture connecting plate 31. The lower end of the puncture connecting plate 31 has a connecting part directly articulated with the universal joint 24, and the sliding block 5 of the first guide rail 4 also has a connecting part directly articulated with the universal joint 24. The end connecting piece 33 is detachably connected to the side of the puncture connecting plate 31 away from the first guide rail 4. Specifically, the upper end of the puncture connecting plate 31 is provided with a connecting column 311, and the upper end of the end connecting piece 33 is provided with a connecting hole 321 matched with the connecting column 311. The hole diameter of the connecting hole 321 is greater than the diameter of the connecting column 311, and after the end connecting piece 33 is inserted into the connecting column 311 through the connecting hole 321, the end connecting piece 33 can be rotated clockwise or counterclockwise against the connecting column 311.

[0099] In order to fix the puncture connecting plate 31 and the end connecting piece 33, a fixing column 312 is arranged on the second side of the puncture connecting plate 31 in the embodiment, and a fixing hole is arranged on the end connecting piece 33 to be inserted and fixed with the fixing column 312. After the connecting column 311 and the connecting hole 321 are matched, the end connecting piece 33 can be rotated to insert the fixing hole into the fixing column 312. The fixing column 312 has a spindle-shaped connecting part, and the fixing hole has a groove body matched with the connecting part.

[0100] In order to facilitate the installation and disassembly of the end connecting piece 33 and the end detachable piece 33, the lower end of the end connecting piece 33 is provided with a first buckle groove 322 on both sides in the embodiment, and the end detachable piece 33 is provided with a second buckle groove 332 which is buckled and fixed with the first buckle groove 322. The first buckle groove 322 and the second buckle groove 332 can be fixedly connected in a buckled manner. In order to facilitate disassembly, the two sides of the end detachable piece 33 are provided with outwardly expanding handles 333, which are arranged to be able to press the second buckle groove 332 out of the first buckle groove 322. In order to facilitate the fixation of the puncture sleeve 34, a first fixing groove 323 is arranged on the end connecting piece 33 towards one end of the end detachable piece 33 in the embodiment, and a second fixing groove 331 corresponding to the first fixing groove 323 is arranged in the second buckle groove 332, and the puncture sleeve 34 is fixed between the first fixing groove 323 and the second fixing groove 331. When the puncture sleeve 34 is cylindrical, the first fixing groove 323 and the second fixing groove 331 can be semicircular.

[0101] Embodiment 2:

[0102] According to another aspect of the present application, a hybrid robot kinematics analysis method is provided, which can be applied to the hybrid robot of embodiment 1. In this embodiment, the hybrid robot in the above embodiment is simplified and described in detail. Specifically, the hybrid robot includes an upper motion platform and a lower motion platform, the upper motion platform includes two first linear motion members, a first horizontal support, an upper universal joint and a sliding block 5, the two first linear motion members are connected in parallel and then connected in series with the first horizontal support, the upper universal joint and the sliding block 5.

[0103] The lower motion platform includes two second linear motion members, a second horizontal support and a lower universal joint, the two second linear motion members are connected in parallel and then connected in series with the second horizontal support, the lower universal joint and the end support 3, and the upper motion platform and the lower motion platform are connected in parallel through the sliding block 5 and the guide rail on the end support 3.

[0104] In this embodiment, the upper motion platform and the lower motion platform correspond to the two motion platforms 2 in the above embodiment respectively, and the two first linear motion members in the upper motion platform correspond to the two linear motion members 22 in the upper motion platform 2 in the above embodiment. The two second linear motion members in the lower motion platform correspond to the two linear motion members 22 in the lower motion platform in the above embodiment.

[0105] The first horizontal support and the second horizontal support in the embodiment are composed of the connecting piece 23 and the parallelism limiting member 21 in the above embodiment. The upper joint and the lower joint correspond to the joints 24 in the upper moving platform and the joints 24 in the lower moving platform in the above embodiment respectively. The slider, the end support and the guide rail in the embodiment correspond to the slider 5, the end support 3 and the first guide rail 4 in the above embodiment respectively.

[0106] According to the hybrid robot structure, it contains both parallel structure and serial structure. When kinematics analysis is performed, the complexity is obviously increased by using only geometric analysis method, and the DH modeling method cannot be directly applied. Therefore, the geometric analysis method and the DH modeling method are combined in the embodiment to perform kinematics analysis.

[0107] Specifically, the hybrid robot is in a horizontal placement state when it works normally. The upper moving platform and the lower moving platform include four linear motion members, two first linear motion members and two second linear motion members. In the embodiment, the two second linear motion members are referred to as the first linear motion member and the second linear motion member, and the two first linear motion members are referred to as the third linear motion member and the fourth linear motion member.

[0108] The rear ends of the four linear motion members are hinged to the mounting platform through bearings. The origin of the base coordinate system can be set at the intersection of the centers of the rear end bearings of the four linear motion members, i.e. the intersection of the hinge points, and is denoted as O0. The x-axis is perpendicular to the plane formed by the centers of the rear end bearings of the four linear motion members, and the positive direction is towards the elongation direction of the end support. The z-axis is perpendicular to the horizontal plane and upward. The y-axis is determined by the right-hand rule.

[0109] For the lower moving platform, the rear ends of the first linear motion member and the second linear motion member are hinged to the mounting platform through bearings, and the front ends are hinged to the second horizontal support through bearings, specifically to the two ends of the connecting piece in the lower moving platform. The two bearing center points of the front ends are denoted as O 2- According to the above embodiment, the connecting piece and the parallelism limiting member can only move in translation in the XOY plane under the constraint of the second guide rail, and cannot rotate around the z-axis. The front end of the second horizontal support is hinged to the lower joint through a rotating shaft, the lower joint is hinged to the end support through a rotating shaft, and the end support can be rigidly connected to an end sleeve. A puncture needle can be installed in the end sleeve.

[0110] The upper moving platform and the lower moving platform are the same. The two bearing center points of the front ends of the third linear motion member and the fourth linear motion member are denoted as O 2+The upper motion platform and the lower motion platform are different in that the upper universal joint in the upper motion platform is hinged with a sliding block installed on a guide rail of the end support.

[0111] As can be seen from the above, the motion structure of the hybrid robot has the following characteristics: for the upper motion platform, the third linear motion member and the fourth linear motion member are connected in parallel, and then connected in series with the first horizontal support, the upper universal joint and the sliding block; for the lower motion platform, the first linear motion member and the second linear motion member are connected in parallel, and then connected in series with the second horizontal support, the lower universal joint and the end support; finally, the upper motion platform and the lower motion platform are connected in parallel through the sliding block and the guide rail of the end support, and the upper and lower structures together determine the position and posture of the puncture needle in the end sleeve.

[0112] Let:

[0113] l l : the distance between the center points of the rear end fixed bearings of the first linear motion member and the second linear motion member, which is equal to the distance between the center points of the rear end fixed bearings of the third linear motion member and the fourth linear motion member;

[0114] ls: the distance between the center points of the two bearings on the first horizontal support, which is equal to the distance between the center points of the two bearings on the second horizontal support;

[0115] l h : the distance between the center points of the rear end fixed bearings of the third linear motion member and the fourth linear motion member, which is equal to the distance between the center points of the rear end fixed bearings of the first linear motion member and the second linear motion member;

[0116] l g1 : the length of O 2- to the center point of the front end rotating shaft of the lower universal joint, which is also equal to the length of O 2+ to the center point of the front end rotating shaft of the upper universal joint;

[0117] l g2 : the length of the front end rotating shaft center point of the lower universal joint to the center point of the sleeve, i.e. the length of the front end rotating shaft center point of the upper universal joint to the center point of the sleeve;

[0118] The position coordinates (x 2- , y 2- , z 2- ) of O 2- ;

[0119] The position coordinates (x 2+ , y 2+ , z 2+ ) of O 2+ .

[0120] In the embodiment, the kinematics analysis method applied to the hybrid robot comprises:

[0121] A base coordinate system is established, and a geometric analysis method is used to obtain position coordinates of key points in the parallel structure part of the upper motion platform and the lower motion platform based on the base coordinate system, for example, the position coordinates of O 2- and the position coordinates of O 2+ ;

[0122] The base coordinate system is a coordinate system established with the intersection point of the hinge points of the first ends of the two first linear motion members and the hinge points of the first ends of the two second linear motion members as the origin, that is, a coordinate system established with O0 as the origin;

[0123] The rotation angles of the upper universal joint and the lower universal joint are obtained;

[0124] A DH model of the series structure part of the upper motion platform and the lower motion platform is established based on the position coordinates and the rotation angles;

[0125] A DH parameter table of the upper model and the lower model is determined based on the DH model;

[0126] The pose of the end sleeve and the puncture needle is solved based on the DH parameter table, and a conversion matrix of any point on the puncture needle relative to the base coordinate system is obtained.

[0127] The embodiment achieves the purpose of first analyzing the parallel structure part using a geometric analysis method and then analyzing the series structure part using a DH model according to the structural characteristics of the hybrid robot, and finally obtaining an accurate analytical expression of the pose of the end sleeve and the puncture needle, thereby realizing the technical effect of more efficiently kinematically analyzing the hybrid robot, and further solving the problem that the kinematics analysis method in the related art is not suitable for kinematically analyzing the hybrid robot.

[0128] (1) Side length correction

[0129] According to the description of the structure of the hybrid robot in the above embodiment, the linear motion member includes a motor and a connecting arm, and the connecting arm and the elongated rod of the motor have a certain included angle, so that the configuration of a single linear motion member is a triangle, and side length correction is needed when it is simplified to a linear type. When the motor elongation is 0, the initial length of the electric cylinder is set as m0, and the motor elongation in the i-th linear motion member is Δm i (i = 1, 2, 3, 4);

[0130] The elongated rod and the connecting arm are integrated, the front end of the connecting arm is a bearing hinged with the connecting piece, the length of the connecting arm is e, and the elongated rod of the electric cylinder forms an angle θ aThe distance between the front end of the ith linear motion member and the center point of the rear bearing l i (i = 1, 2, 3, 4).

[0131] It can be deduced from geometric analysis that:

[0132]

[0133] (2) Solve the position coordinates of the key points, that is, obtain the position coordinates of O 2- and the position coordinates of O 2+ .

[0134] After the side length correction, as shown in Figure 10 , the parallel structure part in the upper motion platform and the lower motion platform can be simplified as a trapezoidal configuration, and based on the trapezoidal configuration, the position coordinates (x 2- , y 2- , z 2- ) of O 2- and the position coordinates (x 2+ , y 2+ , z 2+ ) of O 2+ can be obtained by geometric analysis.

[0135] Specifically, it can be deduced from geometric analysis that:

[0136]

[0137] The solution is:

[0138]

[0139] Similarly, it can be obtained that:

[0140]

[0141] It can be easily obtained from structural feature analysis that:

[0142] (3) Determine the two rotation angles of the rotating link, that is, obtain the rotation angles of the upper universal joint and the lower universal joint.

[0143] The rear end and the front end of the upper universal joint and the lower universal joint each have a rotation shaft, the rotation angles of the rear end and the front end of the upper universal joint are respectively set as θ wb+ and θ wf+ , and the rotation angles of the rear end and the front end of the lower universal joint are respectively set as θ wb- and θ wf- . Since the front ends of the first horizontal support and the second horizontal support always move forward along x+, the upper universal joint and the lower universal joint also always move forward along x+, and they only have rotational motion along the x axis, therefore θwb+ =θ wb- θ wf+ =θ wf- Based on the structural and kinematic analysis of the aforementioned hybrid robot, the rotation angle θ wb It is mainly generated by the difference in y-coordinates between the upper and lower O2 points, with a rotation angle θ. wf It is mainly generated by the difference in x-coordinates between the upper and lower O2 points.

[0144] Let: Δx² = x 2+ -x 2- ;

[0145] Δy2=y 2+ -y 2- .

[0146] but:

[0147]

[0148]

[0149] (4) Establish DH model, that is, establish DH model of the serial structure part of the upper motion platform and the lower motion platform based on the position coordinates and the rotation angle, and determine the DH parameter table of the upper model and the lower model based on the DH model.

[0150] Establish the DH model for the series structure in the upper and lower motion platforms, as follows: Figure 11 As shown, the y-direction is determined by the right-hand rule, which is omitted in the figure.

[0151] In the DH model established above, length a represents the length along x. i axis, z i-1 axis and x i The intersection of the axes to O i The distance from the origin; the torsion angle α of the rod represents the distance around x. i The axis, by z i-1 Steering Z i Angle; member offset d i Indicates along z i-1 Axial direction, z i-1 axis and x i Intersection to o i-1 Distance from origin; the rotation angle θ of the rod represents the distance around z. i-1 The axis is determined by x i-1 Turn x i The angle.

[0152] By analyzing the motion structure, the upper and lower layers are decoupled. The end sleeve is located at the end of the lower layer, its position generated by the motion of the lower layer, while its attitude is generated by the position angle difference between the upper and lower layers. Since the second connecting rod does not rotate in the z-axis direction, the position difference of point O2 in the y-direction between the upper and lower layers generates the joint rotation angle, and the rotation angles of the upper and lower layers are equal. The calculated DH parameters of the lower layer model are shown in Table 3-1 (the model of the upper motion platform can be obtained similarly):

[0153] Table 3-1 Model DH Parameter Table of Lower Motion Platform for Miniaturized Hybrid Robot

[0154]

[0155] (5) Solve the pose of the end sleeve and the puncture needle, that is, solve the pose of the end sleeve and the puncture needle based on the DH parameter table, and obtain the transformation matrix of any point on the puncture needle relative to the base coordinate system.

[0156] The positions of the end sleeve and puncture needle are represented by a 4×4 homogeneous transformation matrix as follows:

[0157]

[0158] The homogeneous transformation matrix of the end sleeve relative to the base coordinate system:

[0159] 0 T3 = 0 A1* 1 A2* 2 A3;

[0160] The transformation relationship between the i-th joint, the i-th link, and the i-th coordinate system is as follows:

[0161]

[0162] Let any point on the puncture needle fixed to the end sleeve be relative to O. 3- The position coordinates are (t) x ,t y ,t z ), then its relative to O 3- The homogeneous transformation matrix is:

[0163]

[0164] The transformation matrix T of any point on the puncture needle relative to the base coordinate system is:

[0165] T = 0 T3T tool

[0166] In this embodiment, O 3- It refers to Figure 11The center (x 3- , y 3- , z 3- ) of the coordinate system.

[0167] According to another aspect of the present application, an electronic device is provided, comprising:

[0168] a memory storing execution instructions; and

[0169] a processor executing the execution instructions stored in the memory, so that the processor performs the hybrid robot kinematics analysis method described above.

[0170] According to another aspect of the present application, a readable storage medium is provided, in which execution instructions are stored, the execution instructions being executed by a processor to implement the hybrid robot kinematics analysis method described above.

[0171] According to another aspect of the present application, a robot system is provided, comprising the readable storage medium described above, the robot system being configured to perform kinematics solving based on the execution instructions stored in the readable storage medium.

[0172] The above merely provides preferred embodiments of the present application, but is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A hybrid robot kinematics analysis method, characterized in that, The application is applied to a hybrid robot, the hybrid robot comprising an upper motion platform and a lower motion platform, the upper motion platform comprising two first linear motion members, a first horizontal support, an upper universal joint and a slider, the two first linear motion members being connected in series with the first horizontal support, the upper universal joint and the slider in turn after being connected in parallel, first ends of the two first linear motion members being hinged to a mounting platform, second ends of the two first linear motion members being hinged to the first horizontal support, the first horizontal support, the upper universal joint and the slider being hinged in turn; the lower motion platform comprising two second linear motion members, a second horizontal support and a lower universal joint, the two second linear motion members being connected in series with the second horizontal support, the lower universal joint and a terminal support in turn after being connected in parallel, the upper motion platform and the lower motion platform being connected in parallel through the slider and a guide rail on the terminal support, the terminal support being used for connecting a terminal sleeve, the terminal sleeve being used for mounting a puncture needle, second ends of the two second linear motion members being hinged to the mounting platform, second ends of the two second linear motion members being hinged to the second horizontal support, the second horizontal support, the lower universal joint and the terminal support being hinged in turn; a kinematic analysis method comprising: acquiring position coordinates of key points in the parallel structure part of the upper motion platform and the lower motion platform based on a base coordinate system, the key points comprising center points of the hinged points of the second ends of the two first linear motion members and center points of the hinged points of the second ends of the two second linear motion members; acquiring rotation angles of the upper universal joint and the lower universal joint; establishing a DH model of the series structure part of the upper motion platform and the lower motion platform based on the position coordinates and the rotation angles; determining a DH parameter table of the upper model and the lower model based on the DH model; solving a pose of the terminal sleeve and the puncture needle based on the DH parameter table, and obtaining a conversion matrix of any point on the puncture needle relative to the base coordinate system.

2. The hybrid robot kinematics analysis method according to claim 1, characterized in that, The center point of the hinge point of the second end of the two first linear motion members is O 2+ The center point of the hinge point of the second end of the two second linear motion members is O 2- ; acquiring the position coordinates of the key points in the upper motion platform and the lower motion platform comprises: Obtaining the position coordinates (x 2+ , y 2+ , z 2+ ) of O 2+ and the position coordinates (x 2- , y 2- , z 2- ) of O 2- .

3. The kinematics analysis method of a hybrid robot according to claim 2, characterized in that, the base coordinate system is a coordinate system established with the intersection point of the hinged points of the first ends of the two first linear motion members and the hinged points of the first ends of the two second linear motion members as an origin.

4. The kinematics analysis method of a hybrid robot according to claim 3, characterized in that, acquiring the position coordinates of the key points in the upper motion platform and the lower motion platform based on the base coordinate system comprises: correcting distances between the hinged points of the first ends and the second ends of the first linear motion members; correcting distances between the hinged points of the first ends and the second ends of the second linear motion members; simplifying the parallel structure in the upper motion platform and the lower motion platform into a trapezoidal configuration based on the corrected results; Based on the trapezoidal configuration, the position coordinates of O 2+ and O 2- are obtained by using the geometric analysis method.

5. The kinematic analysis method of a hybrid robot according to claim 4, characterized in that, acquiring the rotation angles of the upper universal joint and the lower universal joint comprises: The rear end and the front end of the upper and lower universal joints each have a rotation shaft, and the rotation angles of the rear end and the front end of the upper universal joint are respectively set as θ wb+ and θ wf+ , and the rotation angles of the rear end and the front end of the lower universal joint are respectively set as θ wb- and θ wf- ; θ wb+ =θ wb- , θ wf+ =θ wf- ; ； ； ； ； The distance between the hinging center points of the first ends of the two first linear motion members and the distance between the hinging center points of the first ends of the two second linear motion members are both l h .

6. The hybrid robot kinematics analysis method according to claim 5, characterized in that, solving the pose of the terminal sleeve and the puncture needle based on the DH parameter table, and obtaining the conversion matrix of any point on the puncture needle relative to the base coordinate system comprises: the pose of the terminal sleeve and the puncture needle is represented by a 4*4 homogeneous transformation matrix as: ； the homogeneous transformation matrix of the terminal sleeve relative to the base coordinate system is: ； wherein, for the ith joint, the transformation relationship between the ith link and the ith coordinate system is as follows: ； in, For the i-th joint in the DH parameter table value, For the i-th joint in the DH parameter table value, For the i-th joint in the DH parameter table value, For the i-th joint in the DH parameter table value; Let any point on the puncture needle fixed with the end sleeve be P, and the position coordinates of P relative to O 3- be (t x ,t y ,t z ). Then the homogeneous transformation matrix of P relative to O 3- is: ; wherein O 3- is the coordinate origin; the conversion matrix T of any point on the puncture needle relative to the base coordinate system is: 。 7. The kinematics analysis method of a hybrid robot according to claim 1, characterized in that, the first horizontal support and the second horizontal support are constrained to be able to only translate in the XOY plane.

8. An electronic device, comprising: comprises: a memory, the memory storing execution instructions; and a processor, the processor executing the execution instructions stored by the memory, such that the processor performs the hybrid robot kinematics solving method of any one of claims 1 to 7.

9. A readable storage medium, characterized by, The execution instructions are stored in a readable storage medium, and the execution instructions are used to implement the hybrid robot kinematics solving method of any one of claims 1 to 7 when executed by the processor.

10. A robot system, characterized by comprise: The readable storage medium of claim 9, the robot system being configured to be capable of kinematics solving based on the execution instructions stored in the readable storage medium.

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