阅读说明：本技术 基于视觉测量的冶金技术探针接插标定方法及其接插系统 (Metallurgical technology probe plugging calibration method based on visual measurement and plugging system thereof ) 是由 魏振红 吴瑞珉 宋希韬 叶长宏 刘俊江 徐国栋 于 2018-09-13 设计创作，主要内容包括：本发明公开了一种基于视觉测量的冶金技术探针接插标定方法及其接插系统,利用视觉传感器、圆柱杆和冶金技术探针构造了约定区域,在约定区域内,视觉传感器检测圆柱杆和冶金技术探针的相对位置和姿态,得到的位置和姿态结果用于控制驱动装置将圆柱杆插入到冶金技术探针内。为了提高接插的精度和可靠性,利用标准探针配合固定装置,对接插的初始位置、姿态、轴线进行有效的标定。接插过程中,驱动装置保证圆柱杆基本保持姿态,以轴线方向为基准进行接插进给运动,实现圆柱杆初始进入冶金技术探针内。随后继续利用视觉传感器校正圆柱杆和冶金技术探针内的有效长度。本发明能够准确完成圆柱杆和冶金技术探针之间的接插。(The invention discloses a metallurgical technology probe plugging calibration method based on visual measurement and a plugging system thereof. In order to improve the accuracy and reliability of plugging, the initial position, the attitude and the axis of the plugging are effectively calibrated by utilizing a standard probe to be matched with a fixing device. In the inserting process, the driving device ensures that the cylindrical rod basically keeps the posture, and the inserting feeding motion is carried out by taking the axis direction as the reference, so that the cylindrical rod initially enters the metallurgical technology probe. The effective length within the cylindrical rod and metallurgical probe then continues to be calibrated using the vision sensor. The invention can accurately complete the insertion between the cylindrical rod and the metallurgical technology probe.)

1. A metallurgical technology probe plugging calibration method based on visual measurement is characterized by comprising the following steps:

a) under the drive of the driving device, the cylindrical rod is moved to a plugging standard position, and the cylindrical rod is adjusted to a standard posture which is calibrated and collected in advance;

b) then the driving device drives the cylindrical rod to move towards the metallurgical technology probe initially along the direction of a standard axis which is calibrated in advance, and the standard posture is kept;

c) the method comprises the following steps that a visual sensor collects physical profiles of a cylindrical rod and a metallurgical technology probe in an appointed area in real time, measures the space relative position of the front end face of the cylindrical rod and the open end face of the metallurgical technology probe, measures the relative space angle of the axis of the cylindrical rod and the axis of the metallurgical technology probe, and calculates the adjustment quantity by means of an algorithm;

d) during the movement of the cylindrical rod towards the metallurgical technology probe, the movement of the driving device is corrected according to the adjustment obtained in the step c), so that the axis of the cylindrical rod is consistent with the axis of the metallurgical technology probe, and the front surface of the cylindrical rod is inserted into the metallurgical technology probe;

e) the vision sensor continuously measures the relative space angle between the axis of the cylindrical rod and the axis of the metallurgical technology probe, meanwhile, the adjustment quantity is calculated by means of an algorithm according to the self deformation of the cylindrical rod, the driving device continuously moves the cylindrical rod according to the adjustment quantity, and the insertion length of the cylindrical rod is guaranteed to meet the standard requirement.

2. The metallurgical technology probe plugging calibration method based on visual measurement as claimed in claim 1, characterized in that: in the step a), the calibration acquisition in advance is as follows:

1) the cylindrical rod rotates at fixed angle intervals by taking a standard axis as a rotating shaft;

2) and when the cylindrical rod rotates for one angle, the visual sensor acquires the front end profile of the cylindrical rod, and the front end profile of the cylindrical rod is compared with the deviation value of the front end profile of the cylindrical rod under different rotation angles to obtain the deformation parameter of the cylindrical rod.

3. The metallurgical technology probe plugging calibration method based on visual measurement as claimed in any one of claims 1 or 2, characterized in that: the standard posture, the standard axis and the standard position are determined by using a standard probe, and the method comprises the following specific steps:

moving the cylindrical rod to a deep hole section attached to a standard probe by using a driving device to obtain a standard posture;

moving the cylindrical rod to a deep hole section attached to a standard probe by using a driving device, repeatedly moving, and taking at least three points to obtain a standard axis;

the standard position is located on the standard axis, within the convention region.

4. The metallurgical technology probe plugging calibration method based on visual measurement as claimed in claim 3, characterized in that: the standard probe is made of an iron material and is manufactured by machining a probe imitating metallurgical technology.

5. The metallurgical technology probe patching system based on visual measurements of any of claims 1-4, comprising: cylindric pole and metallurgical technology probe, the front end of metallurgical technology probe is the opening end, is equipped with a deep hole along the opening end, makes the metallurgical technology probe be cavity setting, supplies the cylindric pole front end along the opening end insert in the deep hole of metallurgical technology probe, its characterized in that still includes: the device comprises a driving device, a fixing device and a vision sensor;

the driving device is used for connecting and fixing the rear end of the cylindrical rod and moving the position of the cylindrical rod;

the fixing device is used for fixing the metallurgical technology probe, so that the open end of the metallurgical technology probe is aligned to the front end of the cylindrical rod;

a convention area is formed between the insertion length of the front end of the cylinder and the insertion length of the open end of the metallurgical technology probe;

the vision sensor has two, and one is located the vertical top in appointed region through fixed bolster, and another is located the horizontal side in appointed region through fixed bolster.

6. The metallurgical technology probe patching system based on visual measurement of claim 5, wherein: the driving device is a multi-axis manipulator.

7. The metallurgical technology probe patching system based on visual measurement of claim 5, wherein: the vision sensor is an industrial camera.

Technical Field

The invention relates to a metallurgical technology-oriented probe, in particular to a metallurgical technology probe plugging calibration method based on visual measurement and a plugging system thereof.

Background

As a comparison document 1, chinese patent publication No. CN 103348228A discloses a method for inserting a long-axis contact rod into an open-ended probe by means of a mechanical centering device and a holding frame including a plurality of sets of the centering devices, but the disadvantages are mainly as follows:

1) the centering device of the method only has a point positioning function but lacks an axial positioning function for the contact rod, so that when the pose of the contact rod is inappropriate, the centering device cannot ensure that the insertion direction of the contact rod is consistent with the longitudinal axis of the probe, and the possibility of angle difference and contact rod insertion failure is improved. Because the axial positioning of the contact rod is increased through the mechanical mechanism, the robot is used for plugging, and under the condition that the plugging pose is deviated, the robot has stronger acting force and counter-acting force on mechanical structures such as tools, positioning devices and the like, and is still not beneficial to smooth plugging.

2) The method is lack of good calibration of the initial pose of the contact rod plugging operation, but the actual situation is that if the initial pose of the contact rod is not properly calibrated, the initial pose of the contact rod is compounded with the defect 1), so that the failure rate of plugging is increased, and the quality of the plugging process is reduced.

3) The method also refers to the fact that when the contact rod is not bent, the bending of the contact rod cannot be pre-judged and checked, and the bending of the contact rod inevitably causes the failure of plugging.

Therefore, the centering device of the comparison document 1 has a point positioning function and lacks an axial positioning function, and in addition, the method lacks good calibration of the initial pose of the contact rod, so that the angular deviation between the long-axis contact rod and the axis of the probe in the plugging process is difficult to ensure, and the quality of the whole plugging process is reduced.

As another example of the comparison document 2, chinese patent publication No. CN 106242426a discloses a method for assembling a slender shaft by using force sense and vision, in which robot pose adjustment is performed by comparing probe poses in collected images and stored in an upper computer by using vision hole finding, but the method mainly has the following disadvantages:

1) the method is lack of calibration for deformation of the slender shaft, and adjustment is carried out through force feedback in the plugging process, so that on one hand, the method is complex to control, and on the other hand, the situation that plugging cannot be carried out due to overlarge deformation cannot be predicted or cannot be compensated through the pose of the slender shaft. Like the CN 103348228A comparative patent, the deformation of the elongated shaft itself greatly affects the plugging process, so that the reliability of the method is reduced.

2) The method introduces a hole searching process, and the process carries out adjustment of an actuating mechanism by comparing the position and the posture of a hole series workpiece stored in an upper computer. The stored position and posture are necessarily deviated from the position and posture of the current hole-series workpiece, such as inconsistent processing of the hole-series workpiece, so that the deviation is also introduced by the method and cannot be compensated by an algorithm.

3) The method is based on vision and force sensors, and the lack of calibration of the cylindrical rod and the hole series workpiece inevitably causes the complexity of an algorithm, and the success rate and the speed of the plugging operation are difficult to ensure.

Therefore, the above-mentioned comparison document 2 has a deviation between the actual probe pose and the stored probe pose, which leads to a deviation in the hole searching stage, and in addition, the lack of calibration for the deformation of the slender shaft itself also leads to a decrease in reliability of the method.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a metallurgical technology probe plugging calibration method based on visual measurement and a plugging system thereof.

In order to achieve the purpose, the invention adopts the following technical scheme:

on one hand, the metallurgical technology probe plugging calibration method based on visual measurement comprises the following steps:

a) under the drive of the driving device, the cylindrical rod is moved to a plugging standard position, and the cylindrical rod is adjusted to a standard posture which is calibrated and collected in advance;

b) then the driving device drives the cylindrical rod to move towards the metallurgical technology probe initially along the direction of a standard axis which is calibrated in advance, and the standard posture is kept;

c) the method comprises the following steps that a visual sensor collects physical profiles of a cylindrical rod and a metallurgical technology probe in an appointed area in real time, measures the space relative position of the front end face of the cylindrical rod and the open end face of the metallurgical technology probe, measures the relative space angle of the axis of the cylindrical rod and the axis of the metallurgical technology probe, and calculates the adjustment quantity by means of an algorithm;

d) during the movement of the cylindrical rod towards the metallurgical technology probe, the movement of the driving device is corrected according to the adjustment obtained in the step c), so that the axis of the cylindrical rod is consistent with the axis of the metallurgical technology probe, and the front surface of the cylindrical rod is inserted into the metallurgical technology probe;

e) the vision sensor continuously measures the relative space angle between the axis of the cylindrical rod and the axis of the metallurgical technology probe, meanwhile, the adjustment quantity is calculated by means of an algorithm according to the self deformation of the cylindrical rod, the driving device continuously moves the cylindrical rod according to the adjustment quantity, and the insertion length of the cylindrical rod is guaranteed to meet the standard requirement.

In the step a), the calibration acquisition in advance is as follows:

1) the cylindrical rod rotates at fixed angle intervals by taking a standard axis as a rotating shaft;

2) and when the cylindrical rod rotates for one angle, the visual sensor acquires the front end profile of the cylindrical rod, and the front end profile of the cylindrical rod is compared with the deviation value of the front end profile of the cylindrical rod under different rotation angles to obtain the deformation parameter of the cylindrical rod.

The standard posture, the standard axis and the standard position are determined by using a standard probe, and the method comprises the following specific steps:

moving the cylindrical rod to a deep hole section attached to a standard probe by using a driving device to obtain a standard posture;

moving the cylindrical rod to a deep hole section attached to a standard probe by using a driving device, repeatedly moving, and taking at least three points to obtain a standard axis;

the standard position is located on the standard axis, within the convention region.

The standard probe is made of an iron material and is manufactured by machining a probe imitating metallurgical technology.

In another aspect, a metallurgical technology probe patching system based on visual measurement includes: cylindric pole and metallurgical technology probe, the front end of metallurgical technology probe is the opening end, is equipped with a deep hole along the opening end, makes the metallurgical technology probe be cavity setting, supplies the cylindric pole front end along the opening end insert in the deep hole of metallurgical technology probe, still includes: the device comprises a driving device, a fixing device and a vision sensor;

the driving device is used for connecting and fixing the rear end of the cylindrical rod and moving the position of the cylindrical rod;

the fixing device is used for fixing the metallurgical technology probe, so that the open end of the metallurgical technology probe is aligned to the front end of the cylindrical rod;

a convention area is formed between the insertion length of the front end of the cylinder and the insertion length of the open end of the metallurgical technology probe;

the vision sensor has two, and one is located the vertical top in appointed region through fixed bolster, and another is located the horizontal side in appointed region through fixed bolster.

The driving device is a multi-axis manipulator.

The vision sensor is an industrial camera.

In the technical scheme, the metallurgical technology probe plugging calibration method based on vision measurement and the plugging system thereof provided by the invention adopt a non-contact vision plugging mode, and guide a driving device to adjust the pose of a cylindrical rod by using vision identification, so that the problem of axis positioning is solved, and a standard probe is introduced, wherein the standard probe exposes the plugging matching surface of the standard probe and the cylindrical rod on the basis of the metallurgical technology probe, and the plugging matching surface has a certain length, so that the initial pose of the cylindrical rod is visually and reliably calibrated, and the vacant technical means in the comparison document 1 is compensated by introducing a method for pre-judging and checking the state of the cylindrical rod by using a vision sensor. The invention also appoints the identification range of the vision sensor, the vision sensor is directly utilized to measure the relative position and the posture of the probe and the cylindrical rod in the current metallurgical technology in the range, and the stored value mentioned in the comparison file 2 is saved, so that the relative deviation of the obtained posture is more accurate and direct, and the invention is more perfect and effective in the aspect of corresponding calibration.

Drawings

FIG. 1 is a schematic diagram of the configuration of the patching system of the present invention;

FIG. 2 is a side view of the patching system of FIG. 1;

FIG. 3A is a side view of a metallurgical probe in the patching system of the present invention;

FIG. 3B is an isometric view of a metallurgical technology probe in the patching system of the present invention;

FIG. 4A is a side view of a reference probe in the patching system of the present invention;

FIG. 4B is an isometric view of a standard probe in the patching system of the present invention;

FIG. 5A is a side view of a fixture in the patching system of the present invention;

FIG. 5B is an isometric view of a securing device in the patching system of the present invention;

FIG. 6 is a schematic diagram of a standard attitude in the patch calibration method of the present invention;

FIG. 7 is a schematic diagram of a method for obtaining a standard axis in the patch calibration method according to the present invention;

FIG. 8 is a schematic diagram of a method for obtaining a standard position in the patch calibration method according to the present invention;

FIG. 9 is a side view of the calibration of the cylindrical rod in the socket calibration method of the present invention;

FIG. 10 is a schematic diagram of a method of cylindrical rod calibration in the patch calibration method of the present invention;

FIG. 11 is a schematic view of the cylindrical rod calibration method of FIG. 10 in the direction A-A.

Detailed Description

The technical scheme of the invention is further explained by combining the drawings and the embodiment.

Referring to fig. 1 to fig. 3B, the metallurgical probe plugging system based on visual measurement according to the present invention includes: the metallurgical technology probe 2 comprises a cylindrical rod 1 and a metallurgical technology probe 2, wherein the front end of the metallurgical technology probe 2 is an open end 21, and a deep hole 22 is formed along the open end 21, so that the metallurgical technology probe 2 is arranged in a hollow mode, and the front end of the cylindrical rod 1 is inserted into the deep hole 22 of the metallurgical technology probe 2 along the open end 21. Different from the prior art, the method further comprises the following steps: the driving device 3, the fixing device 4 and the vision sensor 5 are connected with a computer, the driving device 3 and the vision sensor 5 are also connected with the computer, relevant data measured by the driving device 3 and the vision sensor 5 are obtained according to the computer, and the movement of the driving device 3 is controlled through a calculation method.

Preferably, the driving device 3 is used for connecting and fixing the rear end of the cylindrical rod 1 and moving the position of the cylindrical rod 1, and the driving device 3 adopts a multi-axis manipulator.

Preferably, the fixing means 4 are used to fix the metallurgical probe 2 so that the open end 21 of the metallurgical probe 2 can be aligned with the front end of the cylindrical rod 1.

Preferably, a junction area 6 is formed between the insertion length of the front end of the cylinder 1 and the insertion length of the open end 21 of the metallurgical probe 2, and the junction area 6 includes the front end of the cylinder 1 and the open end 21 of the metallurgical probe 2, and also includes the cylinder 1 and the metallurgical probe 2 which are not less than the insertion length. The detection cost is reduced and the detection precision is improved, the characteristics of the appointed area 6 are based on that the fit clearance between the cylinder 1 and the metallurgical technology probe 2 in practical application is not very large, and the fit tightness is high, so that the inserting length of the cylinder 1 and the metallurgical technology probe 2 which need to be accurately detected is far shorter than the deep hole 22 of the metallurgical technology probe 2. For example, the metallurgical technology probe 2 has an inner diameter of 18mm and the cylindrical rod 1 has an outer diameter of 16 mm.

Preferably, the vision sensor 5 has two, both industrial cameras, one is located vertically above the appointed area 6 through the fixing bracket, and can clearly look down the relative position and angle of the cylindrical rod 1 and the metallurgical technology probe 2 in the appointed area 6, and the other is located horizontally on the side of the appointed area 6 through the fixing bracket, and can clearly look sideways at the relative position and angle of the cylindrical rod 1 and the metallurgical technology probe 2 in the appointed area 6. The spatial positions and postures of the cylinder 1 and the metallurgical technology probe 2 are restored through image comparison and data analysis of a binocular camera.

It is conceivable that when there are several sets of metallurgical technology probes 2 and corresponding fixtures 4, there is no guarantee that the vision sensor 5 is directly above each metallurgical technology probe 2, but that there is an angle. The arrangement of the two vision sensors 5 ensures that the two vision sensors 5, even if there is an angle, can derive the spatial angle and positional deviation between the cylindrical rod 1 and the metallurgical technology probe 2 by means of an image comparison algorithm.

As shown in fig. 4A and 4B, the probe apparatus further includes a standard probe 7, wherein the standard probe 7 is made of ferrous material and is manufactured by machining the probe 2 imitating the metallurgical technology. The standard probe 7 restores the deep hole 71 of the metallurgical technology probe 2, and meanwhile, in order to facilitate the attachment of the cylindrical rod 1 during calibration, a part of the deep hole 71 is removed and exposed, so that a deep hole section 72 is formed. In addition, in order to ensure that the cylindrical standard probe 7 cannot rotate and translate during calibration, the fixing block 8 is used for fixing the standard probe 7, the groove 11 is further formed in the fixing block 8, when the standard probe 7 is placed on the fixing block 8, the section 72 of the deep hole is vertically upward, and the probe axis 9 cannot move and rotate.

Referring to fig. 5A and 5B, the fixture 4 includes at least two support points 41, 42 for supporting the metallurgical probe 2. The support portions of the support points 41, 42 are V-shaped and ensure that the probe axis 9 coincides with the horizontal axis 10 when the metallurgical probe 2 is placed. The support points 42 differ from the support points 41 in that the support points 42 are also connected to the fixing block 8 and cooperate with the grooves 11 on the fixing block 8.

The invention also provides a metallurgical technology probe plugging calibration method based on visual measurement, which comprises the following steps:

a) under the drive of the driving device 3, the cylindrical rod 1 is moved to the insertion standard position 11, and the cylindrical rod 1 is adjusted to a standard posture 12 which is calibrated and collected in advance;

b) then the driving device 3 drives the cylindrical rod 1 to keep a standard posture 12 along a pre-calibrated standard axis 13 direction and initially move towards the metallurgical technology probe 2;

c) the method comprises the steps that a vision sensor 5 located on the top of a convention area 6 detects and collects physical contours of a cylindrical rod 1 and a metallurgical technology probe 2 in the convention area 6 in real time, further angle deviation of a cylindrical rod axis 14 and a probe axis 9 is obtained, meanwhile, the distance between a cylindrical rod end section 15 and a cross section of an open end 21 of the metallurgical technology probe 2 is detected, the vision sensor 5 located on the side of the convention area 6 detects angle deviation of the cylindrical rod axis 14 and the probe axis 9 in real time, meanwhile, the distance between the cylindrical rod end section 15 and the cross section of the open end 21 of the metallurgical technology probe 2 is detected, and according to results of the two vision sensors 5, pose offset of the cylindrical rod 1 is obtained through certain calculation, namely adjustment quantity (△ x, △ y, △ z, △ thetax, △ thetay and △ thetaz).

d) During the movement of the cylindrical bar 1 towards the metallurgical probe 2, modifying the movement of the driving means 3 according to the adjustment (△ x, △ y, △ z, △ θ x, △ θ y, △ θ z) obtained in step c), so as to ensure that the axis 14 of the cylindrical bar coincides with the axis 9 of the probe, thus enabling the front face of the cylindrical bar 1 to be inserted into the metallurgical probe 2;

e) the vision sensor 5 continuously measures relative space angles (△ theta x, △ theta y and △ 0 theta z) of the cylindrical rod axis 15 and the probe axis 9, meanwhile, according to self deformation (△ 1z, β and △ d) of the cylindrical rod 1, adjusting quantities (△ x, △ y, △ z, △ theta x, △ theta y and △ theta z) are calculated by certain calculation, the driving device 3 continuously moves the cylindrical rod 1 according to the adjusting quantities, and the insertion length of the cylindrical rod 1 is guaranteed to meet the standard requirement.

Because the actual relative pose deviation of the cylindrical rod 1 and the metallurgical technology probe 2 is determined in the plugging process, the plugging calibration method directly focuses high-precision visual detection on the acquisition of the relative pose deviation, and the deviation caused by intermediate conversion and theoretical data is eliminated.

During the movement of the cylindrical rod 1 towards the metallurgical technical probe 2 in step a), the calculation of the adjustment by the visual sensor 5 in step c) is carried out in real time.

Referring to fig. 6, the driving device 3 is used to move the cylindrical rod 1 to the deep hole section 72 attached to the standard probe 7, and the posture (θ x, θ y, θ z) of the cylindrical rod 1 displayed in the driving device 3 is recorded, which is the standard posture 12.

Referring to fig. 7, the driving device 3 is used to move the cylindrical rod 1 to the deep hole section 72 of the standard probe 7, and the cylindrical rod is repeatedly moved by at least three points to ensure that each point is attached to the deep hole section 72 of the standard probe 7, and the obtained points are used to obtain the standard axis 13 and recorded in the driving device 3.

Referring to fig. 8, the driving device 3 is used to move the cylindrical rod 1 to fit the deep hole section 72 of the standard probe 7, and the cylindrical rod exits the deep hole section 72 along the standard axis 13 by a certain distance, and the position (x, y, z) of the cylindrical rod displayed in the driving device 3 is recorded, i.e. the standard position 11.

Fig. 9 to 11 show the process of calibrating the deformation of the cylindrical rod 1 itself by using the vision sensor 5.

1) Under the drive of the driving device 3, the cylindrical rod 1 is moved to the insertion standard position 11, and the cylindrical rod 1 is adjusted to a standard posture 12 which is calibrated and collected in advance;

2) FIG. 9 illustrates the state of the cylindrical rod 1 at the standard position 11. the cylindrical rod 1 is rotated at fixed angular intervals α in the direction of rotation of the z-axis with the standard axis 13 as the axis of rotation to obtain different states of the cylindrical rod 1 (see reference numeral B, C in FIG. 10). Total number of rotations is 360/α to obtain the angular series (0, α, … …, 360- α). for convenience, α may take the common divisor of 360. for example, Total 4 rotations, 90 ° each time, the angular series is (0 °, 90 °, 180 °, 270 °);

3) at each angle in the angle sequence, the visual sensor 5 collects the front end profile of the cylindrical rod 1, and compares deviation values of the profiles of the sections at different angles to obtain a deviation value group (S)_A，D₀，D_α，……，D_180/α). For example, having a cross-section A-A at a distance S from the end face 15 of the cylindrical shank_AThe difference D between the profiles when the rotation angle is 0 DEG and 180 DEG_αD1, 90 ° and 270 ° profile difference D_αD2, a deviation value set (S) is obtained_A，D1，D2)；

4) Based on the deviation value set (S)_AD1, D2) in a cylinderUnder the premise that the section of the rod 1 is circular, the maximum deviation △ D of the section profile of the cylindrical rod 1 and the rotation angle β at the moment are calculated to obtain the deformation parameter (S) at the section A-A_A，β，△D)；

5) Since the section A-A can be defined at different positions, the invention sets it as S_AN × △ S (n is 1, 2, … …, n), so that the deformation parameter of the entire front end of the cylindrical rod 1 is obtained as S_A，β，△D)。

The deformation of measuring the cylinder pole has the commonality, is not limited to can guarantee can not make whole connecing to insert the process degree of difficulty and failure rate improvement because the too big deviation of cylinder pole, and at the insertion stage after the cylinder pole has inserted the metallurgical technology probe, the deformation parameter also is used for adjusting the cylinder pole position appearance in order to reduce to insert the degree of difficulty simultaneously. Before plugging starts, whether the deformation of the cylindrical rod is too large needs to be judged, and if the deformation exceeds a rated value, the cylindrical rod needs to be replaced; after the plugging is started, the metallurgical probe is initially inserted into the cylindrical rod until the plugging is completed, and the deformation of the cylindrical rod can be used as a reference value of the pose of the cylindrical rod.

It should be understood by those skilled in the art that the above embodiments are only for illustrating the present invention and are not to be used as a limitation of the present invention, and that changes and modifications to the above described embodiments are within the scope of the claims of the present invention as long as they are within the spirit and scope of the present invention.