CN111912310B

CN111912310B - Calibration method, device and equipment

Info

Publication number: CN111912310B
Application number: CN202010795226.0A
Authority: CN
Inventors: 楼云江; 刘越; 张合明; 王政; 商大伟
Original assignee: Shenzhen Intelligent Manifold Robot Technology Co Ltd
Current assignee: Shenzhen Intelligent Manifold Robot Technology Co Ltd
Priority date: 2020-08-10
Filing date: 2020-08-10
Publication date: 2021-08-10
Anticipated expiration: 2040-08-10
Also published as: CN111912310A

Abstract

The disclosure provides a calibration method, a calibration device, calibration equipment and a storage medium. A calibration method, comprising: respectively acquiring coordinates of a preset number of position points in a first coordinate system and distances from an origin of the first coordinate system; acquiring a second coordinate system; acquiring calibration parameters aiming at the second coordinate system according to the coordinates of the position points in the first coordinate system and the distance; calibrating the second coordinate system according to the calibration parameters. This disclosure can realize accurate measurement calibration, and convenient operation has promoted user experience.

Description

Calibration method, device and equipment

Technical Field

The present disclosure relates to the field of measurement, and in particular, to a calibration method, apparatus, device, and storage medium.

Background

In the manufacturing and assembling process of the multi-joint robot, the parts are prone to errors. The conventional robot controls the overall deviation of the robot within a certain range through tolerance. However, since the robot moves strictly according to the kinematics of the robot, the motion model of the robot is necessarily deviated from the actual motion model, which is a main reason for the limited precision range of the robot. And with the use of robot, lead to the wearing and tearing of spare part, will aggravate this kind of deviation more, make the robot can't accomplish the function more accurately.

In order to solve the problem, one solution in the existing solutions is to use an expensive laser tracker to perform end tracking on the assembled robot, and combine a complex algorithm to obtain the real assembled size of the robot, so as to compensate the error caused by the manufacturing and assembling size and the actual size. However, laser trackers are complex to deploy, difficult to use, and expensive. However, other measuring devices can measure the trajectory change of the robot during the movement, but the accuracy is limited, and the same effect as that of the laser tracker cannot be achieved.

At present, the problems of complex use, high price and insufficient precision of other measuring devices of the laser tracker are to be solved.

Disclosure of Invention

The present disclosure has been made to solve the above problems, and an object thereof is to provide a pull wire measurement calibration method, device, system, device, and storage medium that are easy to operate and have high accuracy.

This disclosure provides this summary in order to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

In order to solve the above technical problem, an embodiment of the present disclosure provides a calibration method, which adopts the following technical solutions and includes:

respectively acquiring coordinates of a preset number of position points in a first coordinate system and distances from an origin of the first coordinate system;

acquiring a second coordinate system;

acquiring calibration parameters aiming at the second coordinate system according to the coordinates of the position points in the first coordinate system and the distance;

calibrating the second coordinate system according to the calibration parameters.

In order to solve the above technical problem, an embodiment of the present disclosure further provides a calibration apparatus, which adopts the following technical solution, including:

the system comprises a coordinate and stay wire length acquisition module, a first coordinate system and a second coordinate system, wherein the coordinate and stay wire length acquisition module is used for respectively acquiring coordinates of a preset number of position points in the first coordinate system and distances from an original point of the first coordinate system;

the coordinate system acquisition module is used for acquiring a second coordinate system;

a calibration parameter obtaining module, configured to obtain a calibration parameter for the second coordinate system according to the coordinate of the location point in the first coordinate system and the distance;

the calibration module is used for calibrating the second coordinate system according to the calibration parameters;

and acquiring an error vector based on a preset model to acquire the calibration parameter.

In order to solve the above technical problem, an embodiment of the present disclosure further provides a calibration device, which adopts the following technical solution, including:

the calibration device as described above;

a wire swinging assembly for guiding the drawn and recovered cable;

a wire winding assembly for circumferentially constantly winding the cable and controlling a position where the cable is pulled out.

In order to solve the above technical problem, an embodiment of the present disclosure further provides a computer device, which adopts the following technical solution, including:

a memory having a computer program stored therein and a processor implementing the method as described above when executing the computer program.

In order to solve the above technical problem, an embodiment of the present disclosure further provides a computer-readable storage medium, which adopts the following technical solutions and includes:

the computer-readable storage medium has stored thereon a computer program which, when executed by a processor, implements the method as described above.

According to the technical scheme disclosed in the present disclosure, compared with the prior art, the main characteristics are that the cable length change in the stay wire measurement calibration device is accurate, and in the telescopic process of the cable, the length change of the feedback line at a high speed can be realized by the method disclosed in the present disclosure, so that the operation is convenient, and the user experience is improved.

Drawings

FIG. 1 is a flow chart of one embodiment of a pull wire measurement calibration method according to the present disclosure;

FIG. 2 is a schematic view of one embodiment of a pull wire measurement calibration device according to the present disclosure;

FIG. 3 is a schematic view of one embodiment of a wire sweep assembly of a wire measurement calibration apparatus according to the present disclosure;

fig. 4A and 4B are schematic views of one embodiment of a trip prevention portion of a wire sweep assembly of a wire measurement calibration apparatus according to the present disclosure, wherein fig. 4A shows a view from a top view of the wire sweep assembly and fig. 4B shows a view from a left view of the wire sweep assembly;

FIG. 5 is a schematic view of an embodiment of a reel of the pull-off measurement calibration apparatus according to the present disclosure;

FIG. 6 is a schematic view of one embodiment of a wire winding assembly of the pull wire measurement calibration apparatus according to the present disclosure;

7A-7B are schematic diagrams illustrating operation of one embodiment of a wire winding assembly of a pull wire measurement calibration apparatus according to the present disclosure, wherein FIG. 7A illustrates a state diagram of an initial operating position and FIG. 7B illustrates a state diagram of an intermediate operating position;

8A-8C are schematic diagrams of one embodiment of a cover of a pull-wire measurement calibration device according to the present disclosure, wherein FIG. 8A shows a state in which the cover is closed, FIG. 8B shows a state in which the cover is restrained at a second angle, and FIG. 8C shows a state in which the cover is restrained at a third angle;

9A-9C are schematic diagrams of three embodiments of a pull-wire measurement calibration system according to the present disclosure having different fixtures;

figure 10 is a schematic diagram of one embodiment of a computer device of a pull wire measurement calibration system according to the present disclosure.

The above and other features, advantages and aspects of various embodiments of the present disclosure will become more apparent by referring to the following detailed description when taken in conjunction with the accompanying drawings. Throughout the drawings, the same or similar reference numbers refer to the same or similar elements. It should be understood that the drawings are schematic and that elements and elements are not necessarily drawn to scale.

Detailed Description

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs; the terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure; the terms "including" and "having," and any variations thereof, in the description and claims of this disclosure and the description of the above figures are intended to cover non-exclusive inclusions. The terms "first," "second," and the like in the description and claims of the present disclosure or in the above-described drawings are used for distinguishing between different objects and not for describing a particular order.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the disclosure. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

In order to make the technical solutions of the present disclosure better understood by those skilled in the art, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings.

[ measuring and calibrating method for wire ]

Referring to fig. 1, a flow chart of one embodiment of a pull wire measurement calibration method according to the present disclosure is shown. The stay wire measurement calibration method comprises the following steps:

s11, respectively acquiring coordinates of a preset number of position points in a first coordinate system and distances from the origin of the first coordinate system, namely stay wire lengths;

here, the first coordinate system is, for example, a real coordinate system of the current measurement calibration apparatus.

Here, in one or more embodiments, the preset number of position points is, for example, 40 position points, and the tool tip of the object to be calibrated is respectively held still at the 40 position points for, for example, 1 second, to record the lengths of the wires at the position points, respectively. A preset number of position points is obtained, for example, by moving the tool tip of the calibrated object; the measured distance is obtained, for example, by measuring the length of the pull wire of the calibration device from the origin of the first coordinate system.

Here, in one or more embodiments, the length of the pull wire is, for example, a distance between a position point of a center point (TCP) of the tool tip of the object to be calibrated to the measurement calibration apparatus.

Here, in one or more embodiments, obtaining a position of the tool center point TCP based on the first coordinate system and measuring a position of the calibration device are further included. For example, through kinematics and coordinate system conversion, the current position Pe of the calibration device to be measured, e.g. the robot, in the current TCP, and the position O of the measurement calibration device in the robot coordinate system can be obtained_EAnd measures information such as a real position and posture of a robot joint coordinate system by measuring a length of a wire of the calibration device through the following algorithm,

l＝‖P_e-O_E‖

s12, acquiring a second coordinate system;

here, in one or more embodiments, the second coordinate system is, for example, a theoretical coordinate system, for example, a coordinate system of a calibration object that is set in advance and can be obtained.

And S13, acquiring calibration parameters aiming at the second coordinate system according to the coordinates and the distance of the position point in the first coordinate system.

Here, in one or more embodiments, the calibration parameter includes at least one of a joint zero point compensation value, a joint arm length compensation value, a joint reduction ratio compensation value, a joint coupling ratio compensation value, and a tool center point compensation value.

Here, the contents of the above calibration parameters are explained as follows:

joint zero point: for example, a robot is provided with a plurality of joints, but each joint has a starting zero point position in the motion process, the conventional zero point position is that a robot manufacturer draws a scribed line on a rotating component of the joint, and when two scribed lines are aligned, the current joint zero point is considered. However, the judgment of the scales by human eyes always generates errors, which leads to zero point inaccuracy and robot precision loss/reduction.

The length of the joint arm: for example, for any type of robot, the joint arm length is a geometrically specific attribute and must be exactly the value for each specification and type of robot. However, the arm length may be inaccurate during the process of assembly, and the precision of the robot may be lost/reduced.

Joint reduction ratio/ohhr ratio: each joint has a reduction ratio, which if mistakenly applied results in a loss/reduction of robot accuracy.

Tool TCP: tool Center Point is the geometric dimension value of the fixed Tool installed on the robot end flange, which is often deviated on the software model and the real object, so compensation is needed, otherwise robot precision is lost/reduced.

And calculating new values by an algorithm, and correcting the coordinate system of the software model to achieve the result that the software model approaches to the hardware model, thereby improving the precision of the robot system.

Here, in one or more embodiments, wherein the error vector is obtained based on a preset model to obtain the calibration parameter, the preset model obtains the error vector based on at least the forward kinematics model and the error model, wherein the error vector is, for example, a deviation of the second coordinate system with respect to the first coordinate system.

Here, in one or more embodiments, further comprising predefining a forward kinematics model and an error model, for example, predefining a relevant algorithm element and an algorithm model by: (1) defining a rotation group with an identity matrix as a unit element and matrix multiplication as a group algorithm:

SO(3)＝{R∈R^3×3|R^TR＝I,detR＝1}

(2) an antisymmetric vector space is defined:

(3) defining an operator ^:

(4) an operator exp is defined, indicating in an exponential product operation formula that a rotation can be used to describe the coordinate system rotation:

exp：so(3)→SO(3),

(5) and an exponential product operation formula is obtained to realize the conversion operation, and the process of converting a complex rotation matrix into the exponential product operation formula is described through the expansion of the exponential product operation formula, so that the complexity of the subsequent formula is greatly simplified. The physical meaning, namely the pivoting of the rigid body, can be briefly described by an exponential product operation formula:

(6) defining a form and position space of the calibration robot system to be measured:

wherein SE (3) represents a homogeneous 4x4 matrix, wherein R is the above rigid body pivoting motion, and R is

A 3x3 matrix is represented. The R matrix can be used to describe the pose of the robot end coordinate system in the previous coordinate system or the base coordinate system, for example; a three-dimensional vector with p of 3x1, for example, can be used to describe the position of the robot end coordinate system in the previous coordinate system or the base coordinate systemAnd (4) placing. Therefore, by this matrix, the position and posture (pose) of the robot tip coordinate system can be determined.

(7) A special expression is defined to derive the mathematical form of the deviation between the coordinate systems:

(8) a special expression is defined to derive the mathematical form of the deviation between the coordinate systems:

^：R⁶→se(3)，

(9) the following transformation is defined to represent the transformation of the spin ξ:

Ad：SE(3)→R^6×6，

the Ad and g represent an error model describing each two joints of the robot, and the physical significance of the model is, for example, the relative relationship between the theoretical position and posture of each joint adjacent to the robot and the real position and posture, namely, the real position and posture can be obtained by superposing the transformation of the Ad and g on the basis of the theoretical position and posture.

(10) Based on the foregoing basis, a forward kinematics model is defined. The physical meaning is, for example, obtaining a pose matrix of the robot joint coordinate system under the robot basic coordinate system:

(11) based on the basis, establishing an error model to describe the deviation between the theoretical coordinate system pose and the real coordinate system pose:

the error vector of the joint rotation (e.g. including kinematic error parameters of the robot) is described by:

the error model of the TCP tool is as follows:

s14, calibrating the second coordinate system according to the calibration parameters;

here, in one or more embodiments, calibration of the control accuracy of the robot is achieved by re-recording the reference point of the zero point using the above-described calibration parameters.

Here, in one or more embodiments, introducing the error model based on the forward kinematics model described above, the following matrix equation may be obtained:

y＝[Q₁,…,Q_n,Q_Γ]p＝Ap

wherein Q is_i＝Ad_i-1-Ad_i Q_Γ＝Ad_n

Wherein p is an error vector used for decoupling to obtain a true error value used for compensating the deviation.

According to the stay wire length obtained by the measurement, the least square fitting is carried out on the error between the calculated value of the forward kinematics model with the error parameter and the actually measured value, so that an analytical expression about the error can be obtained, the calibration parameter needing to be compensated is obtained, and the system precision correction is completed:

y＝dl²＝d((P_e-O_E)^T(P_e-O_E))＝2(P_e-Q_E)^T(dP_e-dQ_E)

wherein:

Q_ωO＝2(P_e-Q_E)^T(-I)

in one or more embodiments, the pull-wire measurement calibration method of the present disclosure further includes securing the pull-wire measurement calibration device to the working plane; the cable is connected to a device to be calibrated, for example a robot, at a preset position, for example a robot TCP.

It should be understood that, although the steps in the flowcharts of the figures are shown in order as indicated by the arrows, the steps are not necessarily performed in order as indicated by the arrows. The steps are not performed in the exact order shown and may be performed in other orders unless explicitly stated herein. Moreover, at least a portion of the steps in the flow chart of the figure may include multiple sub-steps or multiple stages, which are not necessarily performed at the same time, but may be performed at different times, which are not necessarily performed in sequence, but may be performed alternately or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[ stay wire measurement calibrating device ]

In order to implement the technical solution in the embodiment of the present disclosure, an embodiment of the present disclosure provides a pull wire measurement calibration apparatus, as shown in fig. 2, including: the device comprises a coordinate and stay wire length acquisition module 201, a coordinate system acquisition module 202, a calibration parameter acquisition module 203, a calibration module 204 and a position acquisition module 205.

A coordinate and stay wire length obtaining module 201, configured to obtain coordinates of a preset number of position points in a first coordinate system and a distance from an origin of the first coordinate system, respectively; here, in one or more embodiments, the preset number of position points is, for example, 40 position points, and the tool tip of the object to be calibrated is respectively held still at the 40 position points for, for example, 1 second, to record the lengths of the wires at the position points, respectively. A preset number of position points is obtained, for example, by moving the tool tip of the calibrated object; the measured distance is obtained, for example, by measuring the length of the pull wire of the calibration device from the origin of the first coordinate system.

A coordinate system obtaining module 202, configured to obtain the first coordinate system and obtain a second coordinate system according to the coordinate and the length of the pull wire;

here, in one or more embodiments, a position acquisition module 205 is further included for obtaining a position of the tool center point and a position of the measurement calibration device based on a first coordinate system. For example, through kinematics and coordinate system conversion, the current position Pe of the calibration device to be measured, e.g. the robot, in the current TCP, and the position O of the measurement calibration device in the robot coordinate system can be obtained_EAnd measures information such as a real position and posture of a robot joint coordinate system by measuring a length of a wire of the calibration device through the following algorithm,

l＝‖P_e-O_E‖

here, in one or more embodiments, the first coordinate system is, for example, a real coordinate system of the current measurement calibration apparatus, and the second coordinate system is, for example, a theoretical coordinate system, for example, a coordinate system of a calibration object that is set in advance and can be obtained.

A calibration parameter obtaining module 203, configured to obtain a calibration parameter for the second coordinate system according to the coordinate and the distance of the location point in the first coordinate system;

the calibration parameters at least comprise one of a joint zero compensation value, a joint arm length compensation value, a joint reduction ratio compensation value, a joint coupling ratio compensation value and a central point compensation value of the tail end of the tool.

Here, in one or more embodiments, wherein the error vector is obtained based on a preset model to obtain the calibration parameter, the preset model obtains the error vector based on at least a forward kinematics model and an error model; the error vector is, for example, a deviation of the second coordinate system from the first coordinate system.

Here, in one or more embodiments, the method further includes, pre-defining a forward kinematics model and an error model, and the process of pre-defining the relevant algorithm element and the algorithm model is the same as the process of the above-mentioned one embodiment of the pull-wire measurement calibration method of the present disclosure, and is not described here again.

A calibration module 204, configured to calibrate the second coordinate system according to the calibration parameter.

y＝[Q₁,…,Q_n,Q_Γ]p＝Ap

wherein Q is_i＝Ad_i-1-Ad_i Q_Γ＝Ad_n

y＝dl²＝d((P_e-O_E)^T(P_e-O_E))＝2(P_e-Q_E)^T(dP_e-dQ_E)

wherein:

Q_ωO＝2(P_e-Q_E)^T(-I)

it should be understood that although each block in the block diagrams of the figures may represent a module, a portion of which comprises one or more executable instructions for implementing the specified logical function(s), the blocks are not necessarily executed sequentially. Each module and functional unit in the device embodiments in the present disclosure may be integrated into one processing module, or each unit may exist alone physically, or two or more modules or functional units are integrated into one module. The integrated modules can be realized in a hardware mode, and can also be realized in a software functional module mode. The integrated module, if implemented in the form of a software functional module and sold or used as a stand-alone product, may also be stored in a computer readable storage medium. The storage medium mentioned above may be a read-only memory, a magnetic or optical disk, etc.

[ measuring and calibrating device for wire)

Referring now to fig. 3-9, there are shown schematic diagrams of a pull-wire measurement calibration apparatus suitable for use in implementing embodiments of the present disclosure, the apparatus shown being merely an example and not intended to impose any limitations on the functionality or scope of use of embodiments of the present disclosure.

One embodiment of a pull wire measurement calibration apparatus of the present disclosure includes:

the stay wire measuring and calibrating device is used for calibrating a preset coordinate system according to the stay wire lengths of the cables at the position points with the preset number; the stay wire measuring and calibrating device in the embodiment at least comprises a coordinate and stay wire length obtaining unit (module) for respectively obtaining the coordinate of the front end of the cable and the stay wire length when the cable is pulled out at the position points with the preset number;

and the calibration unit (module) is used for acquiring calibration parameters of a coordinate system of the calibrated object according to the coordinates and the length of the stay wire.

Of course, the pull wire measurement calibration apparatus in this embodiment may also include other units or modules.

The cable swinging assembly is used for guiding or following the cable pulled out and recovered by the calibrated object so as to realize the smooth movement of the cable;

a wire winding assembly for drawing and recovering the wire to the wire swinging assembly, and winding the wire around the wire with constant circumference and controlling the wire to keep linear motion when being drawn and recovered;

the encoder is matched with the winding component shaft and used for acquiring the stay wire length of the cable;

the casing is used for protecting the stay wire swinging assembly and is provided with a main body part, a cover part and a connecting piece; the connecting piece is connected with the main body part and the cover part through a first hinge and a second hinge respectively and is used for controlling the overturning angle of the cover part;

and the limiting part is arranged opposite to the pull wire swinging assembly, is tangent to the cable and is used for limiting the cable to limit the movement of the pull wire swinging assembly.

The above-mentioned wire measuring and calibrating device has been described in detail, and will not be described in detail here, and other components will be described in detail below.

As shown in fig. 3, is a schematic view of one embodiment of a wire sweep assembly of a wire measurement calibration apparatus according to the present disclosure; as shown in fig. 3, for example, a floating cycloid head structure, which includes a wire guide wheel 311 for guiding a drawn-out and recovered wire;

here, the cable in the present embodiment is, for example, a linear material that can be assembled, is not easily stretched, and can ensure good winding smoothness, such as a plastic-covered steel wire, but may be another linear material.

The cable guide wheel 311 in this embodiment is, for example, a guide wheel supported by a first bearing guide bearing 312 at an upper portion of a bearing bracket 313 fixed to the wire swinging member 310, and a lower portion of the bearing bracket is connected to a second bearing 314, for example, a remote distance bearing 314, orthogonal to the first bearing guide bearing 312, for enabling the swinging of the guide wheel 311 with smooth movement of the wire. Wherein the remote distance bearing 314 is mounted on a fixed mount 315. Through the remote arrangement of two sets of bearings, the steel wire can smoothly come in and go out when stretching out and drawing back fast. Because the in-out direction of the steel wire is uncertain, the orthogonal bearing group can play a role in quickly following the movement of the cable.

The outer circumference of idler 311 is tangent to the axis of remote bearing 314 and idler bearing 312 is positioned such that the cable passes through the axis of remote bearing 314 and wraps around idler 311.

A retaining portion 316 is provided on the bearing frame 313 at, for example, the same level as the guide bearing 312 to pass through the center of the guide roller 311, which will be described in detail below.

The wire swinging assembly 310 further comprises a peripheral knurl 317 and a joint part 318, the joint part 318 is arranged at one end of the cable and used for connecting the TCP of the robot to be measured when the equipment works and fixing the cable on a limiting part 320 which is described below stably when the equipment does not work, and the peripheral knurl 317 is used for facilitating the taking of the joint part 318.

As shown in fig. 4A and 4B, which are schematic views of one embodiment of the anti-trip portion 316 of the wire sweep assembly of the wire measurement calibration apparatus according to the present disclosure, wherein fig. 4A shows a view from a top view of the wire sweep assembly and fig. 4B shows a view from a left view of the wire sweep assembly;

the retaining portion 316 is, for example, a spring ball screw, and the depth of the flat-end jack screw is controlled to: the clearance between the guide wheel 311 and the steel wire is smaller than the diameter of the steel wire, so that the steel wire is prevented from falling out of the groove of the guide wheel 311. And, for example, the lateral position of the jack screw passes through the center of the guide wheel.

As shown in fig. 3, the pull wire measurement calibration apparatus of the present disclosure further includes a limiting portion 320, such as a hook, disposed opposite the pull wire pendulum assembly 310 and tangent to the cable wire for limiting the wire to limit the movement of the pull wire pendulum assembly 310 when the measurement calibration apparatus is not in operation.

FIG. 5 is a schematic view of one embodiment of a reel of a winding assembly of the pull-wire measurement calibration apparatus according to the present disclosure; as shown in fig. 5, a reel 500, such as in the present embodiment, which is a wire winding assembly, for drawing and recovering a wire to and from a wire swinging assembly 310 and winding the wire with a constant circumference, specifically, the length of the wire wound on the reel 500 for one turn is constant and does not move due to the swinging of the wire, the size from a point of a cable a to a point of a cable B is one circumferential diameter, and the starting point 502 of the cable is fixed, along a circumferential tangent line.

The winding assembly further includes a measuring portion for measuring the pull-off length of the wire cable released from the reel 500, such as an encoder in the present embodiment, in cooperation with the reel 500 shaft to avoid damage to the reel 500 circumference, thereby improving accuracy for obtaining the pull-off length of the cable.

The reel 500 includes a force receiving portion 501, such as a coil spring catching groove, for connecting a force applying member, such as a coil spring, for applying a force in a cable recovery direction to the reel 500 by a contraction force of the coil spring, so that the reel 500 is in a rewound state regardless of a state, particularly when pulled out, and the winding assembly applies a force in a direction opposite to the cable pulling direction to maintain a tensed state of the pulled-back cable, thereby ensuring that the wire is not loosened from the winding portion.

FIG. 6 is a schematic view of one embodiment of a wire winding assembly of the pull wire measurement calibration apparatus according to the present disclosure; as shown, the wire winding assembly 600 is used to maintain the linear motion of the wire when the wire is drawn out and retracted.

The winding assembly 600 includes the reel 500 described above, the central shaft being, for example, the lead screw 601 in the present embodiment, for connecting with the reel 500 and controlling the direction of movement of the reel 500, when the wire is pulled out from the reel 500 for movement, the reel 500 is passively rotated relative to a support portion described below and translated along the axis of the lead screw 601, so that the position where the wire cable is pulled out is unchanged relative to the support portion described below, while the lead screw 601 is rotated;

a support portion for shaft-supporting the lead screw 601 with the reel 500, which in this embodiment comprises, for example, one first-support X-bracket 602 and two second-support

vertical brackets

603, 603.

In one embodiment, for example, the lead screw 601 is integrally and fixedly connected to the reel 500 at one end by a square nut and provided with threads at the other end, the X-shaped bracket 602 is fixed with a central shaft nut, i.e., the lead screw nut 604, and the lead screw 601 is in threaded connection with the X-shaped bracket 602 through the lead screw nut 604, so that the rotation of the reel 500 drives the lead screw 601 to move along the thread of the lead screw nut 604, so that the position where the wire cable is pulled out is unchanged relative to the support portion.

In another embodiment, for example, one end of the screw 601 is fixedly connected with the X-shaped bracket 602 integrally, and the other end is provided with threads, and is connected with the reel 500 through the threads, so that the rotation of the reel 500 moves along the screw 601, and the pulled-out position of the wire cable is unchanged relative to the support part.

The

guide rods

605, 605 in this embodiment are used for connecting one X-shaped bracket 602 and two

vertical brackets

603, 603 and supporting the encoder so as to translate the encoder along with the reel 500 in the axial direction relative to the support part, so as to make the screw rod 601 perform linear motion, and in this embodiment, the

guide rods

605, 605 define the translational motion direction of the reel 500 and the encoder through

linear nuts

607, 607.

Since a slight vibration may occur when the linear nuts 607 move in a straight line, and there may be a case where the two linear nuts 607 do not move synchronously, the winding assembly 600 further includes a buffer elastic part, such as a constant force spring 606 in this embodiment, which is sleeved on the

guide rods

605 and 605 to buffer the vibration during the movement of the linear nuts 607.

Fig. 7A-7B are schematic diagrams illustrating operation of one embodiment of a wire winding assembly 600 of a pull wire measurement calibration apparatus according to the present disclosure, wherein fig. 7A illustrates a state diagram of an initial operating position and fig. 7B illustrates a state diagram of an intermediate operating position; as shown in fig. 7A, the wire is in the initial operating position on the left side of the reel 500, when the wire is pulled out, the reel 500 is rotated passively, and the lead screw 601 is rotated, the lead screw 601 is moved to extend to the left along the thread line of the lead screw nut 604, and fig. 7B shows a state diagram of the intermediate operating position.

The winding assembly 600 realizes a smooth linear motion of the reel 500, so that the wire on the output reel 500 always maintains the same posture without relative displacement.

8A-8C are schematic diagrams of one embodiment of a housing of a pull-wire measurement calibration device according to the present disclosure, where FIG. 8A shows a state where a cover of the housing is closed, FIG. 8B shows a state where the cover of the housing is restrained at a second angle, and FIG. 8C shows a state where the cover of the housing is restrained at a third angle; as shown, the housing includes a body portion, a cover portion 800, and a connector; a cover 800 for effectively protecting the wire swinging assembly 310 from damage caused by external accidents when the device is not in use; and is set such that the highest point of the cover is lower than the level of the cable drawn out and recovered from the wire swinging member 310 when opened at a third angle shown in fig. 8C, for example, 270 ° in the present embodiment.

One end of the connector is connected with the main body part through a first hinge 801, and the other end of the connector is connected with the cover part 800 through a second hinge 802;

the lid 800 is turned over at a first angle, for example, 90 ° by the first hinge 801 to be stopped (not shown), the connection member is turned over at a second angle, for example, 180 ° in this embodiment by the second hinge 802 to be stopped (fig. 8B), and when the lid 800 is turned over at a third angle, for example, 270 ° in this embodiment, with respect to the body portion by the first hinge 801 and the second hinge 802 to be opened, the edge of the lid 800 does not affect the drawing and retrieving of the cable of the wire measuring and calibrating device.

Here, the first angle is at least 90 °, the third angle is at least 270 °, and not limited.

In the present embodiment, the connecting member is of a circular arc angle shape and includes, for example, at least a first portion and a second portion extending in orthogonal directions, the first portion being connected to the first hinge 801, the second portion being connected to the second hinge 802, and the side length of the first portion being larger than the side length of the second portion. In the present embodiment, for example, the first hinge 801 and the second hinge 802 are provided away from the side of the cable drawn out and recovered from the wire measuring calibration apparatus.

In the present embodiment, the side length of the first portion is, for example, a vertical distance between the first hinge 801 and the second hinge 802 when the cover 800 is closed, and the side length of the second portion is, for example, a horizontal distance between the first hinge 801 and the second hinge 802 when the cover 800 is closed.

When the cover 800 is turned open at a third angle, for example, 270 °, the sum of the vertical distance of the edge of the highest point of the cover 800 to the second hinge 802 and the side length of the second portion is less than the horizontal height of the cable drawn and recovered from the wire measuring calibration apparatus.

In this embodiment, for example, the cover 800 further has a recess for receiving the connecting member when the first hinge 801 and the second hinge 802 perform the flip-over restriction.

In the present embodiment, for example, the housing including the cover portion and the body portion is made of a transparent or translucent material.

[ stay wire measurement calibration System ]

In order to achieve the technical solution in the embodiments of the present disclosure, an embodiment of the present disclosure provides a pull wire measurement calibration system, as shown in fig. 9A to 9C, which are schematic diagrams of three embodiments of the pull wire measurement calibration system according to the present disclosure, which have different fixing portions; comprises the stay wire measurement calibration equipment as described above;

the fixing portion is used to fix the wire measuring and calibrating device on the working plane, for example, fig. 9A is a clamping fixing portion, fig. 9B is a screw fixing portion, and fig. 9C is a magnetic seat fixing portion, but the material, shape, fixing manner, etc. of the fixing portion are not limited.

One embodiment of the present disclosure provides a pull-wire measurement calibration system and a computer device to implement the method of pull-wire measurement calibration.

Referring now to FIG. 10, shown is a schematic block diagram of a computer device suitable for use in implementing embodiments of the present disclosure. The computer device in the embodiments of the present disclosure is only an example, and should not bring any limitation to the functions and the scope of use of the embodiments of the present disclosure.

As shown in fig. 10, the electronic device 1000 may include a processing means (e.g., a central processing unit, a graphic processor, etc.) 1001 for controlling the overall operation of the electronic device. The processing device may include one or more processors to execute instructions to perform all or a portion of the steps of the method described above. Further, the processing device 1001 may also include one or more modules for processing interactions with other devices.

Storage device 1002 is used to store various types of data, and storage device 1002 may be a system, apparatus or device that includes various types of computer-readable storage media or combinations thereof, such as electronic, magnetic, optical, electromagnetic, infrared, or semiconductor, or any combination thereof. More specific examples of the computer readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the present disclosure, a computer readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.

Sensor means 1003 for sensing the prescribed measured information and converting it into a usable output signal according to a certain rule may comprise one or more sensors. For example, it may include an acceleration sensor, a gyro sensor, a magnetic sensor, a pressure sensor or a temperature sensor, etc. for detecting changes in the on/off state, relative positioning, acceleration/deceleration, temperature, humidity, light, etc. of the electronic device.

The processing device 1001, the storage device 1002, and the sensor device 1003 are connected to each other by a bus 1004. An input/output (I/O) interface 1005 is also connected to bus 1004.

The multimedia device 1006 may include an input device such as a touch screen, a touch pad, a keyboard, a mouse, a camera, a microphone, etc. for receiving an input signal from a user, and the various input devices may cooperate with various sensors of the sensor device 1003 to perform, for example, a gesture operation input, an image recognition input, a distance detection input, etc.; the multimedia device 1006 may also include an output device such as a Liquid Crystal Display (LCD), speaker, vibrator, etc.

The power supply device 1007, used to provide power to various devices in the electronic equipment, may include a power management system, one or more power supplies, and components to distribute power to other devices.

The communication unit 1008 may allow the electronic device 1000 to perform wireless or wired communication with other devices to exchange data.

Each of the above devices may also be connected to the I/O interface 1005 to implement applications of the electronic apparatus 1000.

While fig. 5 illustrates an electronic device having various means, it is to be understood that not all illustrated means are required to be implemented or provided. More or fewer devices may alternatively be implemented or provided.

In particular, according to an embodiment of the present disclosure, the processes described above with reference to the flowcharts may be implemented as computer software programs. For example, embodiments of the present disclosure include a computer program product comprising a computer program carried on a non-transitory computer readable medium, the computer program containing program code for performing the method illustrated by the flow chart. In such an embodiment, the computer program may be downloaded and installed from a network via the communication means, or may be installed from a storage means. The computer program, when executed by a processing device, performs the above-described functions defined in the methods of the embodiments of the present disclosure.

In the context of this disclosure, a machine-readable medium may be a tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.

It is noted that the computer readable medium described above in this disclosure can be a computer readable signal medium or a computer readable storage medium or any combination of the two. In contrast, in the present disclosure, a computer readable signal medium may comprise a propagated data signal with computer readable program code embodied therein, either in baseband or as part of a carrier wave. Such a propagated data signal may take many forms, including, but not limited to, electro-magnetic, optical, or any suitable combination thereof. A computer readable signal medium may also be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. Program code embodied on a computer readable medium may be transmitted using any appropriate medium, including but not limited to: electrical wires, optical cables, RF (radio frequency), etc., or any suitable combination of the foregoing.

The computer readable medium may be embodied in the electronic device; or may exist separately without being assembled into the electronic device.

Computer program code for carrying out operations for the present disclosure may be written in any combination of one or more programming languages, including but not limited to an object oriented programming language such as Java, Smalltalk, C + +, and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network or connection may be made to an external computer (for example, through the Internet using an Internet service provider). The flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

The units described in the embodiments of the present disclosure may be implemented by software or hardware. Where the name of an element does not in some cases constitute a limitation on the element itself.

The functions described herein above may be performed, at least in part, by one or more hardware logic components. For example, without limitation, exemplary types of hardware logic components that may be used include: field Programmable Gate Arrays (FPGAs), Application Specific Integrated Circuits (ASICs), Application Specific Standard Products (ASSPs), systems on a chip (SOCs), Complex Programmable Logic Devices (CPLDs), and the like.

According to one or more embodiments of the present disclosure, there is provided a calibration method, including:

acquiring a second coordinate system;

According to one or more embodiments of the present disclosure, there is provided a calibration method characterized in that,

obtaining an error vector based on a preset model to obtain the calibration parameter;

the preset model obtains the error vector at least based on a forward kinematics model and an error model;

the error vector is a deviation of the second coordinate system from the first coordinate system.

According to one or more embodiments of the present disclosure, there is provided a calibration method, characterized by further comprising,

the forward kinematics model and the error model are predefined.

the preset number of position points is obtained by moving a tool tip of the calibrated object;

the distance is obtained from a length of a pull wire of a measurement calibration apparatus located at an origin of the first coordinate system;

the length of the pull wire is the distance between the central point of the tool end of the calibrated object and the measurement calibration equipment;

the first coordinate system is a coordinate system of the measurement calibration equipment, and the second coordinate system is a coordinate system of the calibrated object.

and keeping the tool tail end of the calibrated object at the position points of the preset number for a preset time length respectively so as to record the length of the stay wire respectively.

According to one or more embodiments of the present disclosure, there is provided a calibration device, including:

According to one or more embodiments of the present disclosure, there is provided a calibration device, characterized in that,

the error vector is a deviation of the second coordinate system relative to the first coordinate system;

the calibration parameters at least comprise one of a joint zero compensation value, a joint arm length compensation value, a joint reduction ratio compensation value, a joint coupling ratio compensation value and a central point compensation value of the tail end of the tool;

According to one or more embodiments of the present disclosure, there is provided a calibration device, characterized by further comprising,

the first coordinate system is a coordinate system of the measurement calibration equipment, and the second coordinate system is a coordinate system of the calibrated object;

the length of the pull wire is the distance between the central point of the tool end of the calibrated object and the measurement calibration equipment,

the apparatus further comprises a position acquisition module for obtaining a position of a center point of the tool tip and a position of the measurement calibration device based on a first coordinate system.

According to one or more embodiments of the present disclosure, there is provided a calibration apparatus, characterized by comprising,

the calibration device of any of the preceding claims;

a wire swinging assembly for guiding the drawn and recovered cable;

According to one or more embodiments of the present disclosure, there is provided a computer device, characterized by comprising a memory in which a computer program is stored and a processor which, when executing the computer program, implements the method according to any one of the above.

According to one or more embodiments of the present disclosure, a computer-readable storage medium is provided, characterized in that a computer program is stored thereon, which, when being executed by a processor, implements the method according to any one of the above.

The foregoing description is only exemplary of the preferred embodiments of the disclosure and is illustrative of the principles of the technology employed. It will be appreciated by those skilled in the art that the scope of the disclosure herein is not limited to the particular combination of features described above, but also encompasses other embodiments in which any combination of the features described above or their equivalents does not depart from the spirit of the disclosure. For example, the above features and (but not limited to) the features disclosed in this disclosure having similar functions are replaced with each other to form the technical solution.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order. Under certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are included in the above discussion, these should not be construed as limitations on the scope of the disclosure. Certain features that are described in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination.

Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. A method of calibration, comprising:

acquiring a second coordinate system;

calibrating the second coordinate system according to the calibration parameters,

acquiring an error vector based on a preset model to acquire the calibration parameter, and recording the reference point of the zero point again by using the calibration parameter;

according to the distance of the position points, the error between the value calculated by the forward kinematics model with error parameters and the actually measured value is subjected to least square fitting to obtain calibration parameters to be compensated, so as to realize the calibration of precision,

the method further comprises the step of enabling the user to select the target,

predefining the forward kinematics model and the error model;

and the error model determines the rotation of a rotation description coordinate system, the rotation of a rigid body around an axis and the form and position space of the calibration robot system to be measured by an exponential product operation formula, so as to obtain the relative relation between the theoretical position and posture and the real position and posture of each adjacent joint of the robot.

2. The calibration method of claim 1,

3. The calibration method of claim 1,

4. The calibration method of claim 2,

5. A calibration device, comprising:

wherein an error vector is acquired based on a preset model to acquire the calibration parameter, the reference point of the zero point is re-recorded using the calibration parameter,

according to the distance of the position points, performing least square fitting on the error between the value calculated by the forward kinematics model with the error parameter and the actually measured value to obtain a calibration parameter to be compensated, and realizing the calibration of precision;

the error model determines the rotation of a rotation description coordinate system, the rotation of a rigid body around an axis and the form and position space of a calibration robot system to be measured by an exponential product operation formula, so as to obtain the relative relation between the theoretical position and the posture of each adjacent joint of the robot and the real position and posture;

and keeping the tail ends of the tool of the calibrated object at the position points of the preset number for a preset time length respectively so as to record the lengths of the pull wires respectively.

6. The calibration device of claim 5, further comprising,

7. A calibration device, comprising:

the calibration device of any one of claims 5-6;

a wire swinging assembly for guiding the drawn and recovered cable;

8. A computer device comprising a memory having stored therein a computer program and a processor implementing the method of any of claims 1-4 when executing the computer program.

9. A computer-readable storage medium, characterized in that the computer-readable storage medium has stored thereon a computer program which, when being executed by a processor, carries out the method according to any one of claims 1-4.