CN111482957B

CN111482957B - Vision offline demonstrator registration method

Info

Publication number: CN111482957B
Application number: CN201910630591.3A
Authority: CN
Inventors: 张庆久
Original assignee: Shanghai Gene Automation Technology Co ltd
Current assignee: Zhichang Technology Group Co.,Ltd.
Priority date: 2019-07-12
Filing date: 2019-07-12
Publication date: 2020-12-29
Anticipated expiration: 2039-07-12
Also published as: CN111482957A

Abstract

The invention provides a registration method of a visual off-line demonstrator, which is characterized in that a three-dimensional included angle tool is designed, a demonstration sharp point can be jacked to the position, and when the demonstrator rotates in any direction in a small range, the demonstration sharp point is ensured to be still at the same position; the invention uses software algorithm to fit the position of the point of the demonstrator, and the precision is far higher than that of processing and assembling. The teaching cusp can be accurately calculated without knowing design parameters in the registration process, and the method is simple and convenient.

Description

Vision offline demonstrator registration method

Technical Field

The invention relates to the technical field of industrial robot control teaching, in particular to a registration method of a vision off-line teaching instrument.

Background

With the continuous improvement of the industrial automation degree, industrial robots are widely applied in the fields of automobile and automobile part manufacturing industry, heavy machinery, aerospace, ship, chemical industry, electronic industry and the like. In general, teaching of industrial robots mainly comprises two ways of teaching online and teaching offline, while in the robot vision offline teaching system of the present invention, the relative positions of teaching cusps and marker point arrays are fixed, and the precise relative positions of the teaching cusps and marker point arrays in the space must be obtained before working. In general, the array of teach pendant and the teach point are precisely designed, i.e., their relative positions can be obtained from the design drawing. However, in the production process, because of the uncertainty of errors in both machining and assembly, their relative positions must be recalculated, otherwise large precision errors are generated for the application, and the operation is troublesome.

Disclosure of Invention

The invention mainly aims to provide a visual offline demonstrator registration method, which comprises the following specific operation methods:

designing a three-dimensional included angle tool, enabling a teaching sharp point to be capable of jacking to the top end position of the three-dimensional included angle tool, and ensuring that the teaching sharp point is still at the same position when a teaching instrument rotates in any direction in a small range;

rotating the teaching instrument around the three-dimensional included angle tool by n angles, wherein n is any angle, ensuring that a point is at the same position at each position of the teaching instrument main body during rotation, and reconstructing a mark point array at each angle position by using a binocular reconstruction system to obtain n point clouds;

thirdly, matching the point clouds in the n point clouds to obtain relative external parameters, namely a rotation parameter R and a translation parameter T;

and fourthly, if the matching is successful, fitting the accurate positions of the cusps by utilizing the matching relation of the point clouds, wherein the specific method comprises the following steps: the positions of the sharp points are P (x, y, z), the rotation relation between the point cloud Set1 and the point cloud Seti is Seti ═ Set1, but the rotation relation satisfies P (x, y, z) ═ P (x, y, z), because a plurality of groups can be obtained, the values of P (x, y, z) can be fitted by a least square method according to the information, and the accurate positions of the sharp points relative to the array can be obtained;

fifthly, if the matching fails in the third step, the point clouds with failed matching are removed, then the similar positions are collected again until n point clouds capable of being matched correctly are obtained, and then the accurate positions of the cusps are fitted by utilizing the matching relation of the point clouds, wherein the specific method comprises the following steps: the method comprises the following steps of setting the cusp position as P (x, y, z), setting the rotation relation between the point cloud Set1 and the point cloud Seti as Seti (Set 1), and simultaneously satisfying the requirement of P (x, y, z) as P (x, y, z), wherein multiple groups of the point cloud Seti and the point cloud Seti can be obtained;

and sixthly, recording the relative spatial position relation between the point cloud and the cusp.

The LED lamp is arranged on the body of the teaching instrument, and the LED lamp is not arranged on the point of the teaching instrument.

The invention has the beneficial effects that: the invention uses software algorithm to fit the position of the point of the demonstrator, and the precision is far higher than that of processing and assembling. The teaching cusp can be accurately calculated without knowing design parameters in the registration process, and the method is simple and convenient.

When the system is used, the position of a sharp point is calculated according to the led array in the system, namely the sharp point on the teaching instrument is provided, and no led lamp is arranged at the sharp point. The invention provides a registration method for calculating the accurate position of the cusp relative to the array. In the process, data with higher processing precision than that of the machining precision are finally obtained through the acquisition of a vision system and algorithm processing.

The off-line path is generated without depending on tools, and a binocular system is used for tracking a feature array on a teaching pen, calculating the moving track of the pen and then converting the moving track into the track of the robot.

Drawings

FIG. 1 is a schematic diagram of a registration process according to the present invention.

FIG. 2 is a schematic structural diagram of the visual offline teaching instrument of the present invention.

FIG. 3 is a three-dimensional angling tool of the present invention.

Detailed Description

The present application is explained in detail with reference to the drawings and examples:

example 1

fifthly, if the matching in the third step fails, a three-dimensional included angle tool needs to be designed from the first step again until the point cloud matching in the third step succeeds, and then the accurate positions of the point points are fitted by utilizing the matching relation of the point clouds, wherein the specific method comprises the following steps: the method comprises the following steps of setting the cusp position as P (x, y, z), setting the rotation relation between the point cloud Set1 and the point cloud Seti as Seti (Set 1), and simultaneously satisfying the requirement of P (x, y, z) as P (x, y, z), wherein multiple groups of the point cloud Seti and the point cloud Seti can be obtained;

Example 2

Designing a three-dimensional included angle tool, enabling a teaching sharp point to be capable of jacking to the top end position of the three-dimensional included angle tool, and ensuring that the teaching sharp point is still at the same position when a teaching instrument rotates in any direction in a small range; the teaching instrument rotates for 9 angles around the three-dimensional included angle tool, each position of a teaching instrument main body ensures that a point is at the same position during rotation, a binocular reconstruction system is utilized for reconstructing a mark point array at each angle position, so that 9 point clouds are obtained, and each point cloud has 6 points;

matching the point clouds to obtain relative external parameters, namely a rotation parameter R and a translation parameter T; the method comprises the following steps of setting the cusp position as P (x, y, z), setting the rotation relation between the point cloud Set1 and the point cloud Seti as Seti (Set 1), and simultaneously satisfying the requirement of P (x, y, z) as P (x, y, z), wherein multiple groups of the point cloud Seti and the point cloud Seti can be obtained;

the position of the cusp is calculated according to the algorithm

415.70850,468.03960,1702.70700。

The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are intended to illustrate the principles of the invention, but rather that various changes and modifications may be made without departing from the spirit and scope of the invention, which is intended to be covered by the appended claims. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A registration method of a visual off-line demonstrator comprises the following specific operation methods:

rotating the demonstrator by n angles around the three-dimensional included angle tool, ensuring that a sharp point is at the same position at each position of the demonstrator main body during rotation, and reconstructing a mark point array at each angle position by using a binocular reconstruction system to obtain n point clouds;

matching the point clouds in the n point clouds to obtain external parameters of the camera, namely a rotation parameter R and a translation parameter T;

and fourthly, if the matching is successful, fitting the accurate positions of the cusps by utilizing the matching relation of the point clouds, wherein the specific method comprises the following steps: setting the sharp point as P (x, y, z), setting the rotation relation between the point cloud Set1 and the point cloud Seti as Seti [ Ri | Ti ] ] Set1, but simultaneously satisfying P (x, y, z) [ [ Ri | Ti ]. P (x, y, z), because a plurality of groups of [ R | T ] can be obtained, fitting the values of P (x, y, z) by a least square method according to the information, and further obtaining the accurate position of the sharp point relative to the mark point array;

fifthly, if the matching in the third step fails, it is indicated that some acquisition positions are problematic to acquire, the problematic point clouds are removed, the acquisition is continued until n point clouds which can be correctly matched are obtained, and then the accurate positions of the cusps are fitted by using the matching relation of the point clouds, and the specific method comprises the following steps: setting the sharp point as P (x, y, z), setting the rotation relation between the point cloud Set1 and the point cloud Seti as Seti ═ Ri | Ti ]. Set1, but simultaneously satisfying P (x, y, z) ═ Ri | Ti ]. P (x, y, z), because the multiple groups of [ R | T ] can be obtained, fitting the values of P (x, y, z) by the least square method according to the information, and further obtaining the accurate position of the sharp point relative to the mark point array;

and sixthly, recording the accurate position of the sharp point relative to the mark point array.

2. The visual offline demonstrator registration method according to claim 1, wherein a led lamp is disposed on a body of the demonstrator, and no led lamp is disposed on a tip of the demonstrator.