阅读说明：本技术 基于电子凸轮的柔性针往复夹紧穿刺机构及应用方法 (Flexible needle reciprocating clamping puncture mechanism based on electronic cam and application method ) 是由 孙进 姜金 梁立 汪和平 于 2021-10-21 设计创作，主要内容包括：本发明公开了一种基于电子凸轮的柔性针往复夹紧穿刺机构及应用方法,机构包括固定平台,用于安装挡板、穿刺角度调整机构；挡板,并用于支撑柔性针；穿刺角度调整机构,用于调整柔性针的穿刺角度；夹紧装置,用于夹紧柔性针；往复装置,用于带动夹紧装置上的柔性针进给运动进行穿刺,以及穿刺完成后的退出；所述穿刺角度调整机构、夹紧装置与固定平台之间均设有滑轨,穿刺角度调整机构、夹紧装置可随往复装置的前进过程同步滑动；夹紧装置和往复装置的驱动由电子凸轮控制,控制过程以往复装置的驱动作为主轴,以夹紧装置的驱动作为从轴；该机构可以在穿刺过程中避免由针杆变形引发的误差影响。(The invention discloses a flexible needle reciprocating clamping puncture mechanism based on an electronic cam and an application method thereof, wherein the mechanism comprises a fixed platform, a flexible needle reciprocating clamping puncture mechanism and a flexible needle reciprocating clamping puncture mechanism, wherein the fixed platform is used for installing a baffle and a puncture angle adjusting mechanism; a baffle for supporting the flexible needle; the puncture angle adjusting mechanism is used for adjusting the puncture angle of the flexible needle; a clamping device for clamping the flexible needle; the reciprocating device is used for driving the flexible needle on the clamping device to perform feed motion for puncture and withdraw after the puncture is finished; sliding rails are arranged among the puncture angle adjusting mechanism, the clamping device and the fixed platform, and the puncture angle adjusting mechanism and the clamping device can synchronously slide along with the advancing process of the reciprocating device; the driving of the clamping device and the reciprocating device is controlled by an electronic cam, and the control process takes the driving of the reciprocating device as a main shaft and the driving of the clamping device as a driven shaft; the mechanism can avoid the error influence caused by the deformation of the needle rod during the puncture process.)

1. A flexible needle reciprocating clamping puncture mechanism based on an electronic cam is characterized by comprising:

the fixed platform is used for installing a baffle and a puncture angle adjusting mechanism;

the baffle is provided with a through hole through which the flexible needle passes and is used for supporting the flexible needle;

the puncture angle adjusting mechanism is used for clamping the tail end of the flexible needle and driving the flexible needle to rotate so as to adjust the puncture angle of the flexible needle;

the clamping device is used for clamping the flexible needle, and the clamping position is close to the front end of the flexible needle;

the reciprocating device is connected with the clamping device and is used for driving the flexible needle on the clamping device to perform feed motion for puncture and withdraw after the puncture is finished;

sliding rails are arranged among the puncture angle adjusting mechanism, the clamping device and the fixed platform, the sliding directions are all parallel to the puncture direction, and the puncture angle adjusting mechanism and the clamping device can synchronously slide along with the advancing process of the reciprocating device;

the driving of the clamping device and the reciprocating device is controlled by an electronic cam, and the driving of the reciprocating device is used as a main shaft and the driving of the clamping device is used as a driven shaft in the control process; the clamping device clamps the flexible needle in the advancing process of the reciprocating device, and the clamping device is loosened in the resetting process of the reciprocating device; the flexible needle is punctured in a stepping mode in a reciprocating mode.

2. The electronic cam based flexible needle reciprocating clamping puncture mechanism as claimed in claim 1, wherein the clamping device comprises a first motor base, a first servo motor, a first screw rod, a fixed clamping table, a sliding clamping block;

the first motor base is matched with a first sliding rail fixed on the fixed platform and can slide along the first sliding rail; the first servo motor is fixed on the first motor base; the first servo motor drives the first screw rod to drive the sliding clamping block to slide along the fixed clamping table, and the sliding clamping block is matched with the fixed clamping table to clamp the flexible needle.

3. The electronic cam based flexible needle reciprocating clamping puncture mechanism as claimed in claim 1, wherein the reciprocating means comprises a third motor base, a second servo motor, a second lead screw, a lead screw slider;

the second servo motor is installed on the fixing platform through a third motor base, two ends of the second lead screw are supported on the fixing platform through bearing seats, the second servo motor is used for driving the second lead screw and driving the lead screw sliding block to move in a reciprocating mode, and the lead screw sliding block is fixed to the side end of the connecting piece and used for driving the clamping device connected with the connecting piece to move synchronously.

4. The electronic cam-based flexible needle reciprocating clamping puncturing mechanism as claimed in claim 1, wherein said puncturing angle adjustment mechanism comprises a second motor mount, a stepper motor, a collet;

the stepping motor is fixed on a second motor base, the second motor base is fixed with the linear sliding block, and the linear sliding block is matched with the linear sliding rail; the stepper motor is connected to a chuck for clamping the distal end of the flexible needle.

5. The method for applying the electronic cam based flexible needle reciprocating clamping puncturing mechanism as claimed in any one of claims 1 to 4,

firstly, acquiring motion track data of center point positions of a clamping device, establishing a space track point set, establishing a Cartesian coordinate system by taking the sliding direction of the clamping device as a transverse axis and the motion direction of a reciprocating device as a longitudinal axis, and establishing an electronic cam table and fitting an electronic cam curve according to the established relation of a master axis and a slave axis;

secondly, the initial puncture angle, the clamping state and the position of the sexual needle are respectively adjusted through the puncture angle adjusting mechanism, the clamping device and the reciprocating device; driving the main shaft and the auxiliary shaft according to the electronic cam curve;

and finally, the main shaft realizes reciprocating motion, the driven shaft realizes clamping and loosening of the flexible needle along with the reciprocating motion of the main shaft, and the flexible needle is driven to feed in a clamping time period.

Technical Field

The invention belongs to the field of intelligent medical robot control and decision making, and particularly relates to a flexible needle reciprocating clamping puncture mechanism based on an electronic cam and an application method.

Background

In a minimally invasive surgery, the flexible needle can better perform target puncture capable of avoiding obstacles by virtue of the characteristics of the flexible needle. However, the front end of the needle is subjected to tissue resistance in the puncture process, and the needle rod can deform under the action of forces at two ends, so that the track in the needle point direction is influenced to a certain extent, and the puncture precision is reduced.

A winding type flexible needle puncturing mechanism (patent publication No. 112370125A) is invented by Zhao Yangjiang et al, the university of Harbin Lei Shih in 2020, and a part of flexible needles wind a lead screw to shrink the flexible needles during puncturing so as to reduce puncturing deformation. Shao national celebration of Harbin's university in 2020 invented a parallel lead screw based flexible needle puncturing mechanism (invention patent publication No. 112656487A), and a clamping mechanism adopting the automatic pencil clamping principle replaces a supporting mechanism, so that the needle shaft is stressed more uniformly in the puncturing process, the puncturing deformation is effectively prevented, and the puncturing speed and rhythm are difficult to control. A double-mechanical-claw-based flexible needle puncture mechanism (patent publication No. 112168309A) is invented by Zhao Yangjiang et al, the university of Harbin Ridgery in 2020, and double mechanical claws are adopted to clamp flexible needles to alternately feed the needles, so that the warping of a needle body in the puncture process is avoided, and the deformation of the needle rod of the flexible needle is caused when a rear mechanical arm clamps the flexible needles in the alternate process.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a flexible needle reciprocating clamping puncture mechanism based on an electronic cam and an application method thereof.

The technical solution for realizing the purpose of the invention is as follows:

an electronic cam based flexible needle reciprocating clamping lancing mechanism comprising:

the fixed platform is used for installing a baffle and a puncture angle adjusting mechanism;

the baffle is provided with a through hole through which the flexible needle passes and is used for supporting the flexible needle;

the puncture angle adjusting mechanism is used for clamping the tail end of the flexible needle and driving the flexible needle to rotate so as to adjust the puncture angle of the flexible needle;

the clamping device is used for clamping the flexible needle, and the clamping position is close to the front end of the flexible needle;

the reciprocating device is connected with the clamping device and is used for driving the flexible needle on the clamping device to perform feed motion for puncture and withdraw after the puncture is finished;

sliding rails are arranged among the puncture angle adjusting mechanism, the clamping device and the fixed platform, the sliding directions are all parallel to the puncture direction, and the puncture angle adjusting mechanism and the clamping device can synchronously slide along with the advancing process of the reciprocating device;

the driving of the clamping device and the reciprocating device is controlled by an electronic cam, and the driving of the reciprocating device is used as a main shaft and the driving of the clamping device is used as a driven shaft in the control process; the clamping device clamps the flexible needle in the advancing process of the reciprocating device, and the clamping device is loosened in the resetting process of the reciprocating device; the flexible needle is punctured in a stepping mode in a reciprocating mode.

An application method of a flexible needle reciprocating clamping puncture mechanism based on an electronic cam comprises the steps of firstly, obtaining movement track data of a central point of a clamping device, establishing a space track point set, establishing a Cartesian coordinate system by taking the sliding direction of the clamping device as a transverse axis and the movement direction of the reciprocating device as a longitudinal axis, and establishing an electronic cam table and fitting an electronic cam curve according to the established relation of a main axis and a subordinate axis;

secondly, the initial puncture angle, the clamping state and the position of the sexual needle are respectively adjusted through the puncture angle adjusting mechanism, the clamping device and the reciprocating device; driving the main shaft and the auxiliary shaft according to the electronic cam curve;

and finally, the main shaft realizes reciprocating motion, the driven shaft realizes clamping and loosening of the flexible needle along with the reciprocating motion of the main shaft, and the flexible needle is driven to feed in a clamping time period.

Compared with the prior art, the invention has the following remarkable advantages:

firstly, by adopting the reciprocating clamping mechanism, the error influence caused by the deformation of the needle shaft can be avoided in the puncturing process, and the puncturing precision is improved;

secondly, the reciprocating clamping mechanism adopted by the invention is used as an auxiliary puncture mechanism to replace a flexible needle supporting mechanism and a feeding mechanism, so that the structure is more compact and the control is more convenient;

and thirdly, the control method of the electronic cam is adopted, so that the motion tracks are smoothly connected, the running smoothness of the device is improved, and the stability of the device is enhanced.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a schematic view of the clamping device of the present invention;

FIG. 3 is a schematic structural view of the flexible needle glide of the present invention;

FIG. 4 is a schematic view of the reciprocating device of the present invention;

FIG. 5 is a schematic diagram of the motion trajectory of the present invention;

FIG. 6 is a schematic view of an electronic cam curve of the present invention;

Detailed Description

The invention is further described with reference to the following figures and detailed description:

as shown in fig. 1, a flexible needle reciprocating clamping puncture mechanism based on an electronic cam comprises a clamping device 1, a puncture angle adjusting mechanism 2, a reciprocating device 3, a fixed platform 4 and a baffle 5;

the baffle 5 is provided with a through hole through which the flexible needle passes and is used for supporting the flexible needle;

with reference to fig. 2 and 3, the clamping device 1 includes a first motor base 15, a first servo motor 16, a coupler 14, a first screw rod 13, a fixed clamping table 11, and a sliding clamping block 12;

the first motor base 15 is matched with a first slide rail 40 fixed on the fixed platform 4 and can slide along the first slide rail 40, and the sliding direction is parallel to the puncture direction; a first servo motor 16 is fixed on a first motor base 15 through a bolt, a coupler 14 is arranged on a motor shaft and used for driving a first screw rod 13, two ends of the first screw rod 13 are provided with fixed clamping platforms 11 through bearings, a sliding clamping block 12 is in threaded fit with the first screw rod 13 and is matched with a sliding groove in the fixed clamping platforms 11, the sliding clamping block 12 can slide along the fixed clamping platforms 11 under the driving of the first screw rod 13, the sliding direction is perpendicular to the puncture direction, and the sliding clamping block 12 is matched with the fixed clamping platforms 11 to clamp flexible needles. The lower end of the fixed clamping table 11 is connected with a micro slide block 22 through a connecting piece 23, the micro slide block 22 is matched with a micro slide rail 21 fixed on the fixed platform 4 and can slide along the micro slide rail 21 in a matching way, and the sliding direction is parallel to the puncture direction.

With reference to fig. 3 and 4, the reciprocating device includes a third motor base 36, a second servo motor 37, a second lead screw 33, and a lead screw slider 32; the second servo motor 37 is mounted on the fixed platform 4 through a third motor base 36, a coupler 35 is mounted on a motor shaft and used for driving a second lead screw 33, two ends of the second lead screw 33 are mounted on the fixed platform 4 through a tail end bearing seat 31 and a front end bearing seat 34, a lead screw sliding block 32 is matched with the second lead screw 33 and can reciprocate along the second lead screw 33 under the driving of the second servo motor 37, and the moving direction is parallel to the puncture direction. The screw rod slide block 32 is fixed with the side end of the connecting piece 23, and the screw rod slide block 32 moves to drive the connecting piece 23 to move, so that the clamping device is driven to move synchronously.

Referring to fig. 3, the puncture angle adjusting mechanism 2 includes a second motor base 28, a stepping motor 27, and a chuck 25; the stepping motor 27 is fixed on the second motor base 28, the second motor base 28 is fixed with the linear sliding block 29, the linear sliding block 29 is matched with the linear sliding rail 24 and can slide along the linear sliding rail, the sliding direction is parallel to the puncture direction, the stepping motor 27 is connected with the chuck 25 through the coupler 26 on the motor shaft, the chuck 25 is used for clamping the tail end of the flexible needle, the stepping motor 27 rotates to drive the flexible needle to rotate, the puncture angle is adjusted, after the puncture angle is finished, the puncture angle adjusting mechanism 2 can move forwards along with the advancing of the reciprocating device 3 in the puncture process, and after the puncture is finished, the puncture angle adjusting mechanism moves backwards along with the retreating of the reciprocating device 3.

The driving of the clamping device 1 and the reciprocating device 3 is controlled by an electronic cam, and the control process takes the second servo motor 37 of the reciprocating device as a main shaft and takes the first servo motor 16 of the clamping device as a slave shaft; when puncture is carried out, the flexible needle is clamped by the clamping device 1 in the advancing process of the reciprocating device 3, the flexible needle is driven to advance by forward rotation of the second servo motor 37, then the flexible needle is loosened by the clamping device 1, the connecting piece 23 and the clamping device 1 are driven to reset by reverse rotation of the second servo motor 37, then the flexible needle is clamped by the clamping device 1, the flexible needle is driven to advance by forward rotation of the second servo motor 37, and the flexible needle is fed in a stepping mode in the advancing and resetting circulating process. After the puncture is finished, the flexible needle is pushed out, the process is opposite, the clamping device 1 clamps the flexible needle in the retreating process of the reciprocating device 3, the clamping device 1 is loosened in the resetting process, and the flexible needle is stepped and retreated in the retreating and resetting circulating process.

An application method of a flexible needle reciprocating clamping puncture mechanism based on an electronic cam is an electronic cam controller control method based on a fifth-order polynomial, a master-slave axis is established based on motion characteristics, an electronic cam table is established based on a motion track of a space track point set, and a fifth-order polynomial curve is adopted to connect all position control points to form a complete electronic cam curve; and controlling the main shaft and the slave shaft to move according to the space track, namely when the main shaft runs to a point of the space track, the slave shaft runs to the point along with the main shaft according to the coordinate relation of the electronic cam curve. The space track point set is midpoint coordinate data of the puncture clamping mechanism.

The application method of the flexible needle reciprocating clamping puncture mechanism based on the electronic cam comprises the following steps:

firstly, according to the feeding characteristics of a flexible needle, acquiring motion track data of a center point position of a clamping device, establishing a space track point set, taking the sliding direction of the clamping device as a transverse axis, and taking the motion direction of a reciprocating device as a Cartesian coordinate system established by a longitudinal axis, and acquiring a motion track as shown in FIG. 5;

secondly, the state and the position of the clamping device and the initial puncture angle of the flexible needle are respectively adjusted through a first servo motor, a second servo motor and a stepping motor, the puncture angle of the flexible needle is adjusted through the stepping motor, and the main shaft and the auxiliary shaft are driven according to the electronic cam curve;

and finally, driving a second screw rod to reciprocate by a second servo motor of the main shaft, driving the clamping device to repeatedly clamp the flexible needle by a first servo motor of the auxiliary shaft, and driving the puncture angle adjusting mechanism to feed along the linear slide rail in a clamping time period.

The puncture clamping mechanism and the application method provided by the invention are characterized in that the reciprocating clamping mechanism can be adopted, the error influence caused by needle shaft deformation can be avoided in the puncture process, the puncture precision is improved, the adopted reciprocating clamping mechanism is used as an auxiliary puncture mechanism to replace a flexible needle supporting mechanism and a feeding mechanism, the structure is more compact, the control is more convenient, the control method of an electronic cam is adopted, the motion tracks are smoothly connected, the running smoothness of the device is improved, and the stability of the device is enhanced.