WO2020073929A9

WO2020073929A9 - Operation trolley, and robotic arm optical target positioning device and positioning method thereof

Info

Publication number: WO2020073929A9
Application number: PCT/CN2019/110205
Authority: WO
Inventors: 刘飞香; 郑大桥; 秦念稳; 夏毅敏; 韩奉林; 何锐波; 曾苗筠; 孙敏亮; 杨肖; 覃宗柱
Original assignee: 中国铁建重工集团股份有限公司
Priority date: 2018-10-09
Filing date: 2019-10-09
Publication date: 2020-07-23
Also published as: CN108827264A; WO2020073929A1; CN108827264B

Abstract

A robotic arm optical target positioning device, comprising a target (1) mounted at the tail end of a boom (5) of a robotic arm and perpendicular to an extending direction of the tail end of the boom, two-dimensional coordinate information of a light spot on the target being able to be acquired; an inclination sensor (3) mounted to the target and used for measuring an inclination attitude of the target; an optical rangefinder (2) capable of projecting a collectable light spot on the target, and capable of obtaining a beam length between the optical rangefinder and the target; and a controller for obtaining dynamic coordinate pose information of the tail end of the boom. Further disclosed are a positioning method using the robotic arm optical target positioning device, and an operation trolley. The positioning device and method improve the positioning accuracy of an arm frame of a trolley, and reduce pose errors caused by deformation of the arm frame. By means of the optical target, the response speed is fast, the position resolution is high, the reliability is high, and the detection data is only related to the energy center of the light spot. The present invention can realize real-time automatic measurement, and does not need manual intervention in the measurement process.

Description

Operating trolley and its mechanical arm optical target positioning device and positioning method

Technical field

The invention relates to the field of engineering machinery, in particular to an optical target positioning device of a work trolley and its mechanical arm. In addition, the present invention also relates to a positioning method using the above device.

Background technique

In the process of tunnel construction, in order to prevent the surrounding rock from deforming and breaking, it is usually necessary to strengthen the surrounding rock by erecting arches, installing anchor rods, hanging steel mesh, and spraying concrete. Take the tunnel arch multifunctional operation trolley as an example. This trolley is an automated tunnel construction equipment integrating arch positioning, installation, and welding. The core operating boom is a multi-degree-of-freedom tandem mechanism. The joint position and posture enable the end work device to achieve the predetermined position and posture is the basic requirement of the work trolley, and it is also the key technology in its development.

However, due to the long arm frame, many joints, and heavy weight of the operating trolley, it is prone to flexible deformation, and there are dimensional errors in various parts after processing and assembly. It is very technically difficult to achieve precise positioning of the end operating device. Usually based on the boom structure and motion laws, the robot kinematics modeling method is used to establish the boom kinematics calibration model, but this method improves the positioning accuracy by identifying geometric errors, ignoring the large scale and low The deformation factors caused by rigidity and the flexible deformation of the boom will interfere with the identification of geometric errors. Although there are methods for identifying and correcting non-geometric errors in series structures, they can only deal with simple structures or small mechanical problems, such as Chinese patent CN106671134A. The trolley boom involves various unfavorable factors such as variable cross-section, contact, clearance, etc., and the method of direct calibration through the whole is not suitable for the positioning of the work trolley boom.

Therefore, how to provide a high-precision positioning device and positioning method is a technical problem that needs to be solved by those skilled in the art.

Summary of the invention

The purpose of the present invention is to provide a work trolley and its mechanical arm optical target positioning device, which can accurately obtain the dynamic coordinate pose information of the mechanical arm through the vector synthesis rule, and improve the positioning accuracy. Another object of the present invention is to provide a positioning method using the above device.

In order to solve the above technical problems, the present invention provides a mechanical arm optical target positioning device, including:

The target is installed at the end of the movable arm of the mechanical arm and is perpendicular to the extension direction of the end of the movable arm, and can obtain the two-dimensional coordinate information of the light spot on the target and the incident angle of the beam;

Inclination sensor, installed on the target and used to measure the inclination attitude of the target;

The optical distance meter is installed at the head end of the fixed arm of the mechanical arm, the light beam emitted by the optical distance meter is parallel to the extension direction of the fixed arm, and can project the collectable light spot on the target, And can obtain the beam length between the optical distance meter and the target;

The controller obtains the dynamic coordinate pose information of the boom end according to the installation size of each component, the incident angle, the inclination attitude, the beam length, and the two-dimensional coordinate information.

Preferably, the inclination sensor is specifically a dual-axis inclination sensor.

Preferably, the optical distance meter is specifically a laser distance meter.

Preferably, the target is specifically a two-dimensional light spot position sensor.

Preferably, the two-dimensional light spot position sensor is specifically a PSD sensor.

Preferably, the target includes a main body and a light spot collector installed above the main body, and the light spot collector is used to obtain two-dimensional coordinate information of the light spot on the main body.

Preferably, the controller can obtain the pose vector from the center of the head end of the fixed arm to the center of the end of the boom through the formula B C A E D according to the vector synthesis rule, that is, obtain the pose vector of the end of the boom. The dynamic coordinate pose information;

Wherein, A is the pose vector, B is the offset vector between the optical rangefinder and the center of the fixed arm, and C is the optical rangefinder projected to the The beam vector of the target, E is the initial vector from the center of the end of the boom to the initial spot projected by the optical rangefinder on the target before the boom extends, and D is the initial spot to the moving arm. The real-time vector of the real-time light spot projected by the optical rangefinder to the target after the arm is extended.

The present invention provides a work trolley, including a mechanical arm and a mechanical arm optical target positioning device installed on the mechanical arm, the mechanical arm optical target positioning device is specifically the mechanical arm optical target described in any one of the above Target positioning device.

The invention provides a method for positioning an optical target of a mechanical arm of a work trolley, which includes the steps:

Obtain the offset vector between the center of the fixed arm of the optical rangefinder and the robotic arm;

Obtain the beam vector of the optical rangefinder projected to the target after the boom of the robotic arm is extended;

Acquiring an initial vector from the center of the end of the boom to the initial spot projected by the optical rangefinder on the target before the boom extends;

Acquiring a real-time vector from the initial light spot to the real-time light spot projected by the optical rangefinder to the target after the boom extends;

According to the vector synthesis principle and formula B C A E D, the pose vector from the center of the head end of the fixed arm to the center of the end of the boom is obtained, that is, the dynamic coordinate pose information of the end of the boom is obtained;

Wherein, A is the pose vector, B is the bias vector, C is the beam vector, D is the real-time vector, and E is the initial vector.

Preferably, acquiring the initial vector and the real-time vector includes acquiring the installation position of the target, the inclination attitude before and after the boom is extended, and the two-dimensional coordinate information of the initial spot and the real-time spot, according to The initial vector and the real-time vector are derived from the installation position, the inclination attitude and the two-dimensional coordinate information.

The invention provides a mechanical arm optical target positioning device of a work trolley, including a target, which is installed at the end of the boom of the mechanical arm and perpendicular to the extension direction of the end of the boom, and can obtain the two-dimensional light spot on the target Coordinate information; Inclination sensor, installed on the target and used to measure the inclination attitude of the target; Optical rangefinder, installed on the head end of the fixed arm of the robotic arm, the light beam emitted by the optical rangefinder is parallel to the extension direction of the fixed arm, and It can project a collectable spot on the target, and can obtain the beam length between the optical rangefinder and the target; the controller can obtain the boom based on the installation size, inclination attitude, beam length and two-dimensional coordinate information of each component Dynamic coordinate pose information of the end.

The present invention also provides a positioning method using the above-mentioned device, including obtaining the offset vector between the optical rangefinder and the center of the fixed arm of the mechanical arm; obtaining the optical rangefinder to project the target after the boom of the mechanical arm is extended Obtain the initial vector from the center of the boom end to the initial spot of the optical rangefinder projected on the target before the boom extends; obtain the real-time spot from the initial spot to the real-time spot of the optical rangefinder projected to the target after the boom is extended Real-time vector; According to the vector synthesis rule and formula B C A E D, the pose vector from the center of the head end of the fixed arm to the center of the end of the boom is obtained, that is, the dynamic coordinate pose information of the end of the boom is obtained; where A is the pose Vector, B is the offset vector, C is the beam vector, D is the real-time vector, and E is the initial vector.

Through the above positioning device and method, accurate data information is obtained by measuring each component. After processing by the controller, the position and attitude information of the end of the manipulator is obtained in real time through the vector synthesis formula, which improves the positioning accuracy of the boom and reduces the The posture error caused by the deformation of the frame; the optical target is adopted, which has fast response speed, high position resolution and high reliability. The detection data is only related to the energy center of the light spot; real-time automatic measurement, without manual intervention in the measurement process.

The present invention also provides a work trolley comprising the above-mentioned mechanical arm positioning device for optical targets. Since the above-mentioned mechanical arm positioning device for optical targets has the above technical effects, the above work trolley should also have the same technical effects. No more detailed introduction.

BRIEF DESCRIPTION

FIG. 1 is a schematic structural diagram of a specific embodiment of a mechanical arm optical target positioning device provided by the present invention;

2 is a schematic structural view of another specific embodiment of the optical target positioning device for a mechanical arm provided by the present invention;

FIG. 3 is a schematic diagram of vector synthesis of a specific embodiment of the optical target positioning device of the mechanical arm provided by the present invention.

detailed description

The core of the present invention is to provide a working trolley and its mechanical arm optical target positioning device, which can accurately obtain the dynamic coordinate pose information of the mechanical arm through the vector synthesis rule, and improve the positioning accuracy. Another core of the present invention is to provide a positioning method using the above device.

In order to enable those skilled in the art to better understand the solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

Please refer to FIGS. 1 to 3. FIG. 1 is a schematic structural diagram of a specific embodiment of the robotic arm optical target positioning device provided by the present invention; FIG. 2 is another schematic view of the robotic arm optical target positioning device provided by the present invention. A schematic structural diagram of a specific embodiment; FIG. 3 is a schematic vector synthesis diagram of a specific embodiment of the mechanical arm optical target positioning device provided by the present invention.

The specific embodiment of the present invention provides a mechanical arm optical target positioning device of a work trolley, which includes a target 1, an inclination sensor, an optical rangefinder 2 and a controller. The target 1 is installed at the end of the boom 5 of the robotic arm, and is perpendicular to the extension direction of the end of the boom 5, which can obtain the two-dimensional coordinate information of the spot on the target 1 and the incident angle of the beam; the tilt sensor is installed on the target 1. It is used to measure the tilt angle of target 1. When the tilt angle of target 1 is not considered, the tilt sensor can completely determine the normal direction of target 1. The optical rangefinder 2 is installed on the head end of the fixed arm 4 of the robotic arm, and the optical measurement The light beam emitted by the distance meter is parallel to the extension direction of the fixed arm 4, and can project a collectable light spot on the target 1, and can obtain the length of the light beam between the optical distance meter 2 and the target 1; the light spot on the target 1 The two-dimensional coordinate information and the incident angle of the beam, plus the attitude angle obtained by the inclination sensor, can obtain the corresponding three-dimensional space information of the light spot; the controller, according to the installation size, incident angle, inclination attitude, beam length and two The dimensional coordinate information obtains the dynamic coordinate pose information of the end of the boom 5.

The target 1 is specifically a two-dimensional spot position sensor. The two-dimensional spot position sensor is the target 1. It is directly installed at the end of the boom 5 of the robotic arm to obtain the two-dimensional coordinate information of the spot on the target 1 and the beam position. The incident angle and the inclination angle sensor are directly installed on the two-dimensional light spot position sensor. Of course, the target 1 can also be a separate support structure installed on the robotic arm, and the two-dimensional light spot position sensor and the inclination angle sensor are installed on the target 1. All are within the protection scope of the present invention.

The head end and the end of the robot arm are defined according to the direction in which the boom 5 extends. The boom extends from the head end to the end, that is, the end of the boom 5 close to the fixed arm 4 is the head end of the boom 5. The end of the movable arm 5 away from the fixed arm 4 is the end of the movable arm 5. Similarly, the end of the fixed arm 4 close to the movable arm 5 is the end of the fixed arm 4, and the end of the fixed arm 4 away from the movable arm 5 is the head of the movable arm 5. end.

Using the above device, the positioning method includes the steps:

Obtaining the offset vector between the center of the head end of the optical rangefinder 2 and the fixed arm 4 of the mechanical arm can be determined according to the installation position of the optical rangefinder 2 and pre-calibration.

Obtain the beam vector of the optical rangefinder 2 projected to the target 1 after the boom 5 of the robotic arm is extended. The distance can be obtained directly by the optical rangefinder 2, and the beam direction of the optical rangefinder 2 is known, so Get the beam vector directly.

The initial vector from the center of the end of the boom 5 to the initial light spot P1 projected on the target 1 by the optical rangefinder 2 before the boom 5 is extended is obtained by a two-dimensional light spot position sensor. The real-time vector of the initial light spot P1 to the real-time light spot P2 projected by the optical rangefinder 2 to the target 1 after the boom 5 is extended is obtained by the two-dimensional light spot position sensor.

Specifically, acquiring the initial vector and the real-time vector includes acquiring the installation position of the target 1, the inclination posture before and after the boom 5 is extended, the two-dimensional coordinate information of the initial spot and the real-time spot, and the incident angle of the light beam. The spot position sensor collects the planar two-dimensional coordinates of the laser spot on the target 1 and the incident angle of the beam, and then outputs it to the controller. The initial vector and the real-time vector are obtained according to the installation position, the inclination angle attitude, the two-dimensional coordinate information and the beam incident angle. Suppose the pitch angle output by the inclination sensor is α, the roll angle is β, and the horizontal azimuth angle is γ. The original target plane is rotated 3 times with P2 as the center to obtain the current target plane; using the obtained target plane information, Convert the output vector obtained in the form of plane coordinates into a three-dimensional space expression.

According to the vector synthesis rule and formula B C A E D, the pose vector from the center of the head end of the fixed arm 4 to the center of the end of the boom 5 is obtained, that is, the dynamic coordinate pose information of the end of the boom 5 is obtained.

Among them, A is the pose vector, B is the bias vector, C is the beam vector, D is the real-time vector, and E is the initial vector.

In the positioning device provided by the specific embodiment of the present invention, the inclination sensor is specifically a dual-axis inclination sensor 3, the optical rangefinder 2 is specifically a laser rangefinder, and the two-dimensional spot position sensor is specifically a PSD sensor. Both the laser rangefinder and the dual-axis tilt sensor output CAN bus and transmit the measurement data to the controller; the PSD sensor is connected to the controller, and the laser beam of the laser rangefinder irradiates the target 1 and forms a light spot on the target , The PSD sensor transmits the plane two-dimensional coordinates of the laser spot and the incident angle data of the beam to the computer; the controller analyzes and calculates these measurement data, and completes the real-time automatic measurement of the end pose of the robotic arm. Of course, other types of components can also be used, all of which fall within the protection scope of the present invention.

On the basis of the robot arm positioning device provided by the above-mentioned specific embodiments, the controller can obtain the pose vector from the center of the head end of the fixed arm 4 to the end center of the boom 5 according to the vector synthesis rule and the formula B C A E D, That is, the dynamic coordinate pose information of the end of the boom 5 is obtained;

Among them, A is the pose vector, B is the offset vector between the optical rangefinder 2 and the center of the fixed arm 4, C is the beam vector projected by the optical rangefinder 2 to the target 1 after the boom 5 is extended, E Is the initial vector from the center of the end of the boom 5 to the initial spot of the optical rangefinder 2 projected to the target 1 before the boom 5 is extended, D is the initial spot to the optical rangefinder 2 projected to the target 1 after the boom 5 is extended The real-time vector of the real-time spot.

Other methods can also be used to obtain the two-dimensional coordinate information of the light spot. The target 1 includes a main body and a light spot collector 6 installed above the main body. The light spot collector 6 is used to obtain the two-dimensional coordinate information of the light spot on the main body.

Through the above positioning device and method, accurate data information is obtained by measuring each component. After processing by the controller, the position and attitude information of the end of the manipulator is obtained in real time through the vector synthesis formula, which improves the positioning accuracy of the boom and reduces the The posture error caused by the deformation of the frame; machine vision is adopted, the field of view is large, the spot is easy to identify, and the cost is low; real-time automatic measurement, the measurement process does not require manual intervention.

In the positioning device provided by the specific embodiment of the present invention, the inclination sensor is specifically a dual-axis inclination sensor 3, the optical rangefinder 2 is specifically a laser rangefinder, and the spot collector 6 is specifically an industrial camera, and the industrial camera is mounted on the body through a bracket. Above. Both the laser rangefinder and the dual-axis inclination sensor output CAN bus to transmit the measurement data to the controller; the industrial camera is connected to the controller via Ethernet, and the image processing embedded system is used to process the laser spot image information collected in real time; control The device analyzes and calculates these measurement data, and completes the real-time automatic measurement of the end pose of the robotic arm. Of course, other types of components can also be used, all of which fall within the protection scope of the present invention.

In addition to the above-mentioned robot arm positioning device, specific embodiments of the present invention also provide a work trolley including the above-mentioned robot arm positioning device. For the structure of other parts of the work trolley, please refer to the prior art, which will not be repeated here. At the same time, since the most serious deformation of the boom is the secondary telescopic joint of the boom, the above-mentioned device and method are generally applied here, and of course can be applied to other joints.

The optical target positioning device and positioning method of the operating trolley and its mechanical arm provided by the present invention have been described in detail above. Specific examples are used in this article to illustrate the principle and implementation of the present invention. The description of the above examples is only used to help understand the method and core idea of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

A mechanical arm optical target positioning device of a work trolley, which is characterized in that it comprises:

The target (1) is installed at the end of the boom (5) of the mechanical arm and is perpendicular to the extension direction of the end of the boom (5), and can obtain the two-dimensional coordinate information of the light spot on the target (1) And the incident angle of the beam;

An inclination sensor installed on the target (1) and used to measure the inclination attitude of the target (1);

The optical rangefinder (2) is installed on the head end of the fixed arm (4) of the mechanical arm. The light beam emitted by the optical rangefinder (2) is parallel to the extension direction of the fixed arm (4) and can Projecting the light spot that can be collected on the target (1), and being able to obtain the beam length between the optical rangefinder (2) and the target (1);

The controller obtains the dynamic coordinate pose information of the end of the boom (5) according to the installation size of each component, the incident angle, the inclination attitude, the beam length, and the two-dimensional coordinate information.
The mechanical arm optical target positioning device according to claim 1, wherein the inclination sensor is specifically a dual-axis inclination sensor (3).
The mechanical arm optical target positioning device according to claim 2, wherein the optical rangefinder (2) is specifically a laser rangefinder.
The mechanical arm optical target positioning device according to claim 3, characterized in that the target (1) is specifically a two-dimensional light spot position sensor.
The mechanical arm optical target positioning device according to claim 4, wherein the two-dimensional light spot position sensor is specifically a PSD sensor.
The mechanical arm optical target positioning device according to claim 3, wherein the target (1) comprises a body and a light spot collector (6) installed above the body, and the light spot collector (6) ) Is used to obtain the two-dimensional coordinate information of the light spot on the body.
The mechanical arm optical target positioning device according to any one of claims 1 to 6, characterized in that the controller can obtain the fixed arm (4) according to the vector synthesis rule and the formula B C A E D The pose vector from the center of the head end to the center of the end of the boom (5) is the dynamic coordinate pose information of the end of the boom (5);

Wherein, A is the pose vector, B is the offset vector between the optical rangefinder (2) and the center of the fixed arm (4), and C is the position after the boom (5) is extended. The light beam vector projected by the optical rangefinder (2) to the target (1), E is the center of the end of the movable arm (5) to the optical rangefinder (2) before the movable arm (5) extends ) The initial vector of the initial light spot projected to the target (1), D is the initial light spot to the boom (5) after the boom (5) is extended and the optical rangefinder (2) is projected to the target ( 1) The real-time vector of the real-time light spot.
A work trolley, comprising a mechanical arm and a mechanical arm optical target positioning device mounted on the mechanical arm, the mechanical arm positioning device is specifically the mechanical arm according to any one of claims 1 to 7 Optical target positioning device.
A method for positioning an optical target of a mechanical arm of a work trolley, which is characterized in that it comprises the following steps:

Obtain the offset vector between the optical rangefinder (2) and the center of the fixed arm (4) of the mechanical arm;

Obtain the beam vector of the optical rangefinder (2) projected to the target (1) after the boom (5) of the mechanical arm is extended;

Acquiring the initial vector from the center of the end of the boom (5) to the initial light spot projected by the optical rangefinder (2) to the target (1) before the boom (5) extends;

Acquiring the real-time vector of the real-time light spot projected by the optical rangefinder (2) onto the target (1) after the initial light spot is extended to the boom (5);

According to the vector synthesis rule and formula B C A E D, the pose vector from the center of the head end of the fixed arm (4) to the center of the end of the boom (5) is obtained, and the end of the boom (5) is obtained Dynamic coordinate and pose information;

Wherein, A is the pose vector, B is the bias vector, C is the beam vector, D is the real-time vector, and E is the initial vector.
The optical target positioning method of a mechanical arm according to claim 9, characterized in that obtaining the initial vector and the real-time vector includes obtaining the installation position of the target (1) and the extension of the movable arm (5). The inclination attitude of the target (1) before and after exiting and the two-dimensional coordinate information of the initial spot and the real-time spot are based on the installation position, the incident angle, the inclination attitude and the two-dimensional coordinate information The initial vector and the real-time vector are obtained.