CN108555895B

CN108555895B - Taking method, taking structure and intelligent mechanical arm

Info

Publication number: CN108555895B
Application number: CN201711479244.2A
Authority: CN
Inventors: 郎需林; 刘培超
Original assignee: Rizhao Yuejiang Intelligent Technology Co ltd
Current assignee: Rizhao Yuejiang Intelligent Technology Co.,Ltd.
Priority date: 2017-12-29
Filing date: 2017-12-29
Publication date: 2021-12-07
Anticipated expiration: 2037-12-29
Also published as: CN108555895A

Abstract

The invention relates to the technical field of automation, and discloses a taking method, a taking structure and an intelligent mechanical arm, wherein the taking method comprises the following steps: s01 taking a first position of the structure acting on the target, and trying to take the target; s02 detecting whether the lifting structure is subjected to the tilting torque in the lifting process; s03 detecting the tilting torque, descending the taking structure and releasing the target; s04, according to the inclined torque, taking the structure moving position and acting on the second position of the target, and trying to take up the target again; s05 repeating steps S02 to S04 until no tilting torque is detected at the time of rising; s06 outputs a driving force to pick up the target. Before the picking, the proper force application position can be found through a plurality of times of trying and searching, and even if the special target with irregular center of gravity and incapable of inclining in the picking process is faced, the picking and moving actions can be stably finished.

Description

Taking method, taking structure and intelligent mechanical arm

Technical Field

The invention relates to the technical field of automation, in particular to an intelligent target taking method of an intelligent mechanical arm.

Background

The intelligent mechanical arm is a simulated arm structure capable of automatically and intelligently operating, such as a planar multi-joint robot, a stacker crane and the like, and generally comprises a plurality of joint arms and an execution end arranged on the last joint arm, various execution components are arranged on the execution end, and the execution end is moved to a specified coordinate in space through automatic control to realize functions provided by the execution components, such as writing, taking, testing, laser printing and the like.

When an intelligent mechanical arm in the prior art needs to take a target, the intelligent mechanical arm is generally provided with a clamping jaw, a sucking disc and other structures, moves to the upper side of the target, clamps the target through the clamping jaw, or sucks the target through the sucking disc, lifts the target and finishes the taking process. However, this kind of taking method can only be applied to the target that the shape and the center of gravity are regular and do not have the requirement to the slope, and in the face of the special target that has special shape, taking requirement, for example the dish of placing the article, the dish is very easy to incline when directly taking and leads to article to fall, or the sculpture that has special shape, its upper end can not directly be held through the sucking disc, adopts the clamping jaw easily to damage the surface etc. this kind of special target is difficult to take through the intelligent arm among the prior art to the target kind of taking of restriction intelligent arm.

Disclosure of Invention

The invention aims to provide a taking method, a taking structure and an intelligent mechanical arm, and aims to solve the problem that the intelligent mechanical arm in the prior art cannot stably take up and move a special target with an irregular center of gravity and an untilted moving process.

The invention is realized in such a way, and provides an taking method for an intelligent mechanical arm to take a target, wherein the intelligent mechanical arm comprises an execution end and a taking structure arranged at the execution end, and the method comprises the following steps:

s01 the fetching structure acts on the first position of the target to try to fetch the target;

s02, detecting whether the taking structure is subjected to tilting torque in the lifting process;

s03, detecting the tilting torque, descending the taking structure and releasing the target;

s04, according to the inclined torque, the taking structure moves the position and acts on the second position of the target to try to take up the target again;

s05 repeating the steps S02 to S04 until the tilting torque is not detected at the time of rising;

s06 outputs a driving force to pick up the object.

Further, in step S03, the method for moving the position of the picking structure includes:

under the influence of the tilting torque, the pick-up structure is moved in the direction of the portion thereof having a downward tendency to rotate.

when the Nth picking-up attempt is carried out, the judged moving direction is opposite to the judged moving direction when the Nth picking-up attempt is carried out, the moving distance of the Nth picking-up attempt is smaller than the distance between the Nth 1 position and the Nth position of the target, and N is a natural number.

Further, after the step S04, the method further includes the following steps: and changing the distance between the taking structure and the target by detecting the acting force between the taking structure and the target.

Further, in the step S03, the method further includes the following steps: and detecting the acting force between the taking structure and the target to be used as a basis for judging whether the target is completely released.

The invention further provides a taking structure which is arranged at the execution end of the intelligent mechanical arm and comprises a body for taking a target, wherein an installation part is arranged between the body and the execution end, and the installation part comprises a sensor for detecting the tilting torque applied to the taking structure.

Further, the mounting portion includes a projection that is insertable into the actuating end, and the sensor includes a plurality of pressure sensors mounted to respective sidewalls of the mounting portion.

Further, the body is the tray, the installation department is located between tray lower extreme and the execution end upper end.

Further, the body includes the clamping jaw that can open and shut, the installation department is located body one side with carry out between the end one side.

The invention also provides an intelligent mechanical arm which comprises a plurality of joint arms, an execution end arranged on any one of the joint arms and the taking structure.

Compared with the prior art, according to the taking method, the taking structure and the intelligent mechanical arm provided by the invention, when a target needs to be taken up, after the target is taken up in each attempt, the taking part is changed according to the influence of the tilting torque on the taking structure until the gravity center position of the target is found, and after the target is judged not to be subjected to the tilting torque any more when the target is taken up, stable force is output to completely take up the target.

Drawings

FIG. 1 is a schematic diagram of a state structure of an attempted fetch according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a state structure for determining fetching according to a first embodiment of the present invention;

FIG. 3 is a schematic diagram of a state structure of an attempted fetch according to a second embodiment of the present invention;

FIG. 4 is a schematic diagram of a state structure for determining fetching according to the second embodiment of the present invention;

FIG. 5 is a flowchart illustrating steps of a fetching method according to the first and second embodiments of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In the description of the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, and are used merely for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention.

In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

For convenience of description, each step is numbered in the following, the numbering is only used for indicating the step in the text description, the represented steps are not numbered in a logical sequence relationship, the related steps are not necessarily performed in a sequential and linear manner according to the numbered numerical relationship, and the logical relationship and the performing mode among the steps are subject to the specific text description.

The implementation of the present embodiment is described in detail below with reference to specific drawings.

The first embodiment is as follows:

as shown in fig. 1, 2 and 5, in the present embodiment, a fetching method is provided for a smart robot to fetch a target 2, the smart robot including an execution end 12 and a fetching structure 11 mounted on the execution end 12.

The object in this embodiment is a plate 2 placed in a suitable position, which is picked up in a lifting manner, the picking method specifically comprising the steps of:

s01 the first position of the pickup structure 11 acting on the object is selected to be a point on the lower end surface of the dish 2 because of the lifting method. After the contact of the take-up structure 11 to the first position, the plate 2 is lifted with a small force and a slow attempt.

S02, detecting whether the pickup structure 11 is subjected to the tilting torque T while it is being lifted; for example, in the state shown in fig. 1, the handle structure 11 is inevitably subjected to the tilting torque T when it is lifted. Specifically, a force feedback sensor may be employed as an element for detecting the tilting torque T.

S03, which indicates that the pickup structure 11 does not exactly find the center of gravity of the dish 2, and if it continues to rise, it will inevitably cause the dish 2 to fall over, so that the pickup structure 11 is lowered and released from the dish 2.

S04 the take-up structure 11 is moved into position and acts on the second position of the tray 2, i.e. another point on the lower end surface of the tray 2, in response to the tilting torque T.

S05 repeats the above steps S01 to S04 until the tilt torque T is not detected at the time of rising, as shown in fig. 2, indicating that the pickup structure 11 has found the position of the center of gravity of the dish 2.

S06 outputs a driving force to lift the tray 2, and the tray 2 is lifted.

It is easily understood that if the tilting torque T is not detected in S03, the process directly proceeds to step S06.

It can be seen from the above process that the picking method in this embodiment finds the center of gravity of the dish 2 through multiple attempts to lift, and finally can stably lift the dish 2 to complete the picking step according to the detection of the torque force feedback.

Although not shown in the drawings, it is easy to understand that the center of gravity of the plate 2 inevitably changes when different articles are placed on the plate, and the plate 2 can be lifted up with a special purpose by automatically finding the center of gravity position according to a plurality of attempts by the picking method in this embodiment without the plate 2 being overturned in the whole picking process. In the present embodiment, the tray 2 is taken as an example, and since the tray is supported, in practical application, the tray can be used for other targets with irregular center of gravity, such as sculptures.

In step S03, the method for taking the position of the structure 11 includes:

under the influence of the tilting torque, the handling structure 11 is moved in the direction of its portion having a downward tendency to rotate. For example, in fig. 1, the right end of the taking structure 11 tends to rotate downward when it is subjected to the tilting torque, which indicates that the center of gravity of the dish 2 should be at the right side, so that the taking structure 11 moves to the right side

If the direction of movement is judged to be right at the time of picking up on 1 trial and left at the time of picking up on 2 nd trial, it is said that the 2 nd trial takes up the position where the selection action point exceeds the center of gravity, the center of gravity should be between the first position and the second position, and therefore the distance moved after the 2 nd trial should be smaller than the distance between the first position and the second position. Preferably, in step S03, the method for taking the position of the structure 11 includes:

when the Nth picking attempt is carried out, the judged moving direction is opposite to the moving direction of the Nth-1 picking attempt, the moving distance of the Nth picking attempt is smaller than the distance between the Nth-1 position and the Nth position of the target, wherein N is a natural number.

Preferably, in step S03, it is clearly judged that tray 2 has been released sufficiently to ensure that tray 2 does not fall off after removing structure 11, so that the following steps are also included in this step: the acting force between the taking structure 11 and the plate 2 is detected to be used as a basis for judging whether the plate 2 is completely released. If it is detected that there is still a force between the take-off 11 and the plate 2, indicating that the plate 2 is not completely released from its rest, direct removal of the take-off 11 may cause the plate 2 to fall. If no force is detected between the pick-up structure 11 and the plate 2, this indicates that the plate 2 has been placed stably on a flat surface, at which point the pick-up structure 11 can be removed safely. In this step, a force feedback sensor may be employed as a specific detection element.

This embodiment still provides structure of taking 11, installs in intelligent mechanical arm's execution end 12, including the body that is used for taking target 2, is equipped with installation department 111a between body and the execution end 12, and installation department 111a is including the sensor that is used for detecting the torque that structure of taking 11 receives.

Since the picking method adopted in the present embodiment is specifically the lifting, the actuator in the present embodiment is a tray 11a whose lower end is mounted on the actuator 12. The actuating end 12 moves to the lower part of the plate 2, drives the moving tray 11a upwards, selects the position of the center of gravity after a plurality of attempts, and stably supports the plate 2.

The actuator 12 has a mounting cavity 121, and the mounting portion 111a is disposed below the tray 11a and is inserted into the actuator 12, so that the tray 11a is fixed above the actuator 12. The sensor includes a plurality of pressure sensors 13 provided on respective side walls of its mounting portion 111 a. When the tray 11a is subjected to the tilting torque, the pressure between the corresponding side wall and the actuating end 12 is inevitably abnormal, and the direction and the magnitude of the tilting torque T can be detected and judged by the pressure sensor 13 as reference data for judging the moving direction and the distance.

Preferably, in order to allow the tray 11a to have a certain deflection stroke and to facilitate detection of a tilting torque, the mounting portion 111a and the actuating end 12 may be in clearance fit, so that a certain tilt can occur within a small angular range.

Preferably, the mounting portion 111a includes an abutment head 112a having a circular arc-shaped end, and the tray 11a can be tilted and rotated within a range when the abutment head 112a abuts against the actuating end 12. In another embodiment, an arc surface may be provided in the actuator 12, and the contact between the arc surface and the abutment head 112a may be detected by an electrical sensor, so as to detect the tilting torque T.

The embodiment also provides an intelligent mechanical arm, which comprises a plurality of joint arms (not shown) and the execution end 12, wherein the joint arms can control the execution end 12 to follow a specified track, output a determined force and reach a specified spatial coordinate point in a specified time under the driving of related circuits and servo motors, and the taking method and the taking part 11 are combined, so that the center of gravity of the plate 2 can be found in multiple attempts, and the plate can be stably taken up.

Example two:

as shown in fig. 3 to 5, the object of the present embodiment is a plate 2 placed in a proper position, which is picked up by holding its edge, and the picking method specifically includes the following steps:

s01 the take-up structure 11 is applied to the first position of the plate 2, which is selected to be a point on the edge of the plate 2 due to the clamping. After the contact of the take-up structure 11 to the first position, it is clamped in place and the plate 2 is taken up with a small force and in slow attempts.

S02, detecting whether the pickup structure 11 is subjected to the tilting torque T while it is being lifted; for example, in the state shown in fig. 3, the handle structure 11 is inevitably subjected to the tilting torque T when it is lifted.

S04 takes the position of structure 11 and acts on the second position of plate 2, i.e. another point on the edge of plate 2, according to the tilting torque T.

S06 outputs a driving force to pick up the dish 2, thereby completing the action of picking up the dish 2.

It can be seen from the above process that the taking method in this embodiment finds the center of gravity of the dish 2 through a plurality of attempts according to the torque force feedback result, and finally can stably take up the dish 2 to complete the taking step. In this embodiment, the plate 2 is used as an example, and since the edge is grasped, the plate can be used for other objects with edges, such as a table, a basin with edges, and the like.

Since the plate 2 is picked up by clamping, the difference between this embodiment and the first embodiment is that the clamping is not actually moved on the whole plane, but only along the edge of the plate 2, which can be regarded as moving left or right along one direction on one plane, and the determination is simpler than that of the first embodiment.

In practical application, as shown in fig. 3 and 4, since the plate 2 is circular or oval, after moving in one direction, the distance between the taking structure 11 and the edge of the plate 2 changes inevitably, in this case, the distance between the taking structure 11 and the plate 2 can be judged by matching with other force feedback detection, the distance is changed to enable the distance between the taking structure 11 and the plate 2 to return to a proper interval, the plate 2 can be stably taken up after force application, and the plate 2 is suitable for taking special targets with irregular center of gravity and untilt process.

Other steps and preferred steps in this embodiment are similar to those in the first embodiment, and will not be described in detail.

Since the taking method adopted in the embodiment is specifically clamping, the taking structure 11 in the embodiment is the clamping jaw 11b installed on the execution end 12, the execution end 12 moves to one side of the plate 2, the clamping jaw 11b approaches the plate 2, the clamping jaw 11b is opened and then closed, the clamping jaw 11b tightly clamps the edge of the plate 2, then the movable clamping jaw 11b starts to be driven upwards, the position of the center of gravity is selected after multiple attempts, and the plate 2 is stably taken up.

The actuator 12 is provided with a mounting cavity 121, the mounting part 111b of the clamping jaw 11b is inserted into the actuator 12, the sensors include a plurality of pressure sensors 13 arranged on the side walls of the mounting part 111b, and when the clamping jaw 11b is inclined and twisted, the pressure sensors 13 on the side walls inevitably detect different pressures, so that the direction of the inclined torque applied to the clamping jaw can be judged.

Preferably, a pressure sensor 13 is also provided on the bottom surface of the mounting portion 111b, and is capable of detecting whether or not there is a mutual pressure between the clamping jaw 11b and the plate 2, and a pressure range (a, b) is preset, where a is a number greater than zero, if the mutual pressure between the clamping jaw and the plate 2 is within (a, b), it indicates that the plate 2 can be gripped and taken up, if the mutual pressure is less than a, it indicates that the clamping jaw 11b is far away from the plate 2, and the plate 2 cannot be gripped, and if the mutual pressure is greater than b, the clamping jaw has already excessively abutted against the plate 2, and the plate 2 may be pushed, and in two abnormal situations that are greater than or less than the pressure range, it is necessary to adjust the distance between the actuating end 12 and the plate 2 so that the mutual pressure between the clamping jaw 11b and the plate 2 returns to (a, b).

The present invention is not limited to the above preferred embodiments, and any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The taking method is used for the intelligent mechanical arm to take the target, the intelligent mechanical arm comprises an execution end and a taking structure arranged at the execution end, and the taking method is characterized by comprising the following steps:

s06 outputting a driving force to pick up the object;

the object is a plate, and the plate is taken up by the taking structure in a supporting mode;

in step S03, the method for moving the position of the picking structure includes: under the influence of the tilting torque, the taking structure moves towards the direction of the part with the downward rotation trend;

2. The fetching method according to claim 1, further comprising, after said step S04, the steps of: and changing the distance between the taking structure and the target by detecting the acting force between the taking structure and the target.

3. The method of taking as claimed in claim 1, wherein in said step S03, further comprising the steps of: and detecting the acting force between the taking structure and the target to be used as a basis for judging whether the target is completely released.

4. The intelligent mechanical arm comprises an taking structure and a positioning structure, wherein the taking structure is arranged at an execution end of the intelligent mechanical arm and is characterized by comprising a body for taking a target;

the mounting part comprises a projection which can be inserted into the execution end, and the sensor comprises a plurality of pressure sensors which are mounted on each side wall of the mounting part; and the mounting part and the execution end form clearance fit.

5. The access structure of claim 4, wherein said body is a tray and said mounting portion is located between a lower end of said tray and an upper end of said actuation end.

6. The access structure of claim 4, wherein said body includes openable and closable jaws, said mounting portion being located between said body side and said actuation end side.

7. A smart robotic arm comprising a plurality of articulated arms and an actuation end disposed on any of said articulated arms, further comprising the access structure of any of claims 4-6.