CN111098311A - Method for improving working beat of robot - Google Patents

Abstract

A method for improving the working beat of a robot comprises the following specific steps: the path planning of the robot is divided into the following five tasks: task 1 (T1): planning on a geometric level according to user instructions, task 2 (T2): coarse path interpolation, task 3 (T3): path fine interpolation, task 4 (T4): drive task, responsible for performing robot (motor) position, task 5 (T5): and the event processing task is responsible for executing IO. According to the method, the delay time is accurately calculated, so that the IO signal is triggered at the moment when the robot reaches the position, the waiting time can be avoided, Tw is reduced to 0, and the beat is effectively improved.

Description

Method for improving working beat of robot

Technical Field

The invention relates to the field of robot control, in particular to a method for improving the working beat of a robot.

Background

Industrial robots are used more and more widely in the field of automation, and along with the popularization of industrial robots and the deepening of people's knowledge about industrial robots, more and more demands on functions and performances are provided. The high precision and the high beat are the most typical requirements, the faster the beat means the higher the production efficiency, and especially in the application of loading and unloading, stacking, unstacking and the like, the beat is a key index for measuring the performance of a robot. On the premise of ensuring the stability and precision of the robot, how to improve the beat is a key technology that all robot companies need to solve. The method provides a method for improving the working rhythm of the robot by applying and analyzing the loading and unloading of the robot.

Disclosure of Invention

According to the technical problem, the invention provides a method for improving the working beat of a robot, which comprises the following specific steps: the path planning of the robot is divided into the following five tasks:

task 1 (T1): planning a geometric layer according to a user instruction;

task 2 (T2): coarse interpolation of the path;

task 3 (T3): fine interpolation of the path;

task 4 (T4): a driving task responsible for executing the robot (motor) position;

task 5 (T5): and the event processing task is responsible for executing IO.

The task 1(T1) performs geometric level planning according to the input of a user program, the output of the task is a rough insertion data block A, the data block A comprises two types of information, namely position information and process information, the process information is a grabbing and releasing signal of a clamp, and can be simply abstracted into signal information, namely IO information; the data block A is processed by a coarse insertion task 2T2 and then is stored in a queue B; the data in the queue B is divided into two types of data after being processed by the fine-insertion task T3: positions and events are stored in different queues C and D respectively; position data stored in the queue C, each position data having a strict execution time, such as 4ms, and the task T4 being a strict real-time task, sequentially taking one position data from the queue C and executing the robot (motor) to the position within a prescribed time interval; the queue D stores event data, which includes several basic information, i.e., IO signals, signal trigger mechanisms, and signal trigger delays, the task T5 scans the entire event queue in each scanning cycle, updates the delay (Td) of each event, immediately processes the event once the delay time of the event is up, i.e., processes the signal, and deletes the event from the queue after the processing is completed.

The data blocks in the queue B simultaneously contain position information and event information, and the position information and the event information are separated into two different queues after passing through a task T3 and are processed by two different tasks; this is because events and locations are not always completely synchronized in processing, and events are classified as:

time event: a certain time interval (Tbe) before reaching the position triggers, which time interval is at least 0;

a location event: triggering when the distance is a certain distance away from the position, wherein the minimum distance is 0;

in the signal processing, the electrical response time (Te) must also be taken into account; the following factors must be considered in calculating the time delay: tbe: time advance, Te: electrical response time, Tq: the execution time of queue C; the calculation formula is as follows:

Td＝Tq–Tbe-Te

through accurate calculation of the delay time Td, the IO signal is triggered at the moment when the robot arrives at the position, so that the waiting time can be avoided, Tw is reduced to 0, and the beat is effectively improved.

The invention has the beneficial effects that: according to the method, the working beat is adjusted, the robot field operator only needs to teach a standard procedure according to the actual working condition, then different speed regulating commands are sent through the debugging and monitoring terminal, and the robot control system can achieve the effect of changing the running speed of the robot by responding to the received speed regulating parameters, so that the working complexity of the operator is greatly simplified, the field processing habit is met, the field processing efficiency is improved, and the standardized operation of the robot is facilitated. According to the method, the delay time is accurately calculated, so that the IO signal is triggered at the moment when the robot reaches the position, the waiting time can be avoided, Tw is reduced to 0, and the beat is effectively improved.

Drawings

FIG. 1 illustrates a loading and unloading scenario involving a robot according to the present invention;

FIG. 2 is a sequence of robot motions in an embodiment of the present invention;

fig. 3 is a schematic diagram of the principle of the present invention.

Detailed Description

The invention will be further explained with reference to the figures:

example 1

As shown in fig. 1 and 2, the loading and unloading of the robot can be simply understood as that the robot takes and places the workpiece among a plurality of stations, and the robot needs to quickly and accurately walk to a determined position and then sends out a control signal to drive the clamp to take or place the workpiece. The lower diagram is a robot loading and unloading working scene with two stations. As shown in the figure, the robot needs to take out the workpiece (black solid small circle) from the work station A and then place the workpiece in the work station B. By breaking down the sequence of robot actions, the pick-and-place can be abstracted into the following work order:

the robot moves from the current position to a pick/place position, called a clamp point, as shown at point a in fig. 2;

the robot moves from the clamp point to the approach point, point b in fig. 2;

the robot moves from the approach point to the working point, as in point c of fig. 2;

the robot sends out a signal to drive the clamp to clamp or loosen;

the robot moves from the working point to the evacuation point, as indicated by point d in fig. 2;

the robot moves from the evacuation point to the clamp point, point a in fig. 2;

the working rhythm of the robot depends on the execution time of a robot path abcda, the robot can move to a point a from the current position of the robot at a high speed under normal conditions, then the robot can move to a point b at a medium speed by reducing the speed, in order to ensure the stability of taking and placing the workpiece, the robot can move to a point c at a lower speed, a signal is triggered, after a short period of time, the robot moves to an evacuation point d, and finally the robot moves to a point a, so that the action sequence of a station is completed. The time required for the complete sequence is therefore:

T＝Tab+Tbc+Tw+Tcd+Tda

wherein Tab is ab segment running time, Tbc is bc segment running time, Tw is waiting time, Tcd is cd segment running time, and Tda is da segment running time.

In order to increase the tempo, it is necessary to shorten the robot movement time and waiting time as much as possible, where three points a, b, d are passing points through which the robot can pass at a higher speed; and c is a working point, and the clamp needs to perform grabbing or releasing action when the speed of the robot is reduced to 0. At present, most robots can achieve little speed reduction or even no speed reduction when processing points a, b and d, thereby achieving the shortest operation time; in general, in order to ensure the stability of the grabbing and releasing, the robot is generally required to reduce the speed of the robot to 0 after reaching the point c, and the grabbing and releasing action is executed after waiting for a certain time. The latency, i.e., Tw, becomes a key to the beat. The method proposes a control method as shown in fig. 1 below for how to shorten Tw.

In this method, the path planning of the robot is divided into the following five tasks:

task 1 (T1): planning a geometric layer according to a user instruction;

task 2 (T2): coarse interpolation of the path;

task 3 (T3): fine interpolation of the path;

task 4 (T4): a driving task responsible for executing the robot (motor) position;

task 5 (T5): and the event processing task is responsible for executing IO.

T1 carries out geometric level planning according to the input of user program, the output is rough insertion data block A, the data block A contains two kinds of information, namely position information and process information, the process information is the grabbing and releasing signals of the clamp, and can be abstracted into signal information, namely IO information; the data block A is processed by a coarse insertion task T2 and then stored in a queue B; the data in the queue B is divided into two types of data after being processed by the fine-insertion task T3: positions and events are stored in different queues C and D respectively; position data stored in the queue C, each position data having a strict execution time, such as 4ms, and the task T4 being a strict real-time task, sequentially taking one position data from the queue C and executing the robot (motor) to the position within a prescribed time interval; the queue D stores event data, which includes several basic information, i.e., IO signals, signal trigger mechanisms, and signal trigger delays, the task T5 scans the entire event queue in each scanning cycle, updates the delay (Td) of each event, immediately processes the event once the delay time of the event is up, i.e., processes the signal, and deletes the event from the queue after the processing is completed.

In fig. 3, the data blocks in the queue B all include the location information and the event information at the same time, and after passing through the task T3, the location information and the event information are separated into two different queues and handed to two different tasks for processing. This is because events and locations are not always completely synchronized in processing, and events are classified as:

time event: a certain time interval (Tbe) before reaching the position triggers, which time interval is at least 0;

a location event: triggering when the distance is a certain distance away from the position, wherein the minimum distance is 0;

meanwhile, the electrical response time (Te) must also be considered when processing the signal; the following factors must be considered in calculating the time delay: tbe: time advance, Te: electrical response time, Tq: the execution time of queue C; the calculation formula is as follows:

Td＝Tq–Tbe-Te

through accurate calculation of the delay time Td, the IO signal is triggered at the moment when the robot arrives at the position, so that the waiting time can be avoided, Tw is reduced to 0, and the beat is effectively improved.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications can be made without departing from the principle of the present invention, and these modifications should also be construed as the protection scope of the present invention.

Claims (3)

1. A method for improving the working beat of a robot comprises the following specific steps: the path planning of the robot is divided into the following five tasks:

task 1 (T1): planning a geometric layer according to a user instruction;

task 2 (T2): coarse interpolation of the path;

task 3 (T3): fine interpolation of the path;

task 4 (T4): a driving task responsible for executing the robot (motor) position;

task 5 (T5): and the event processing task is responsible for executing IO.

2. The method for improving the working cycle of the robot as claimed in claim 1, wherein the task 1(T1) performs geometric planning according to the input of the user program, and the output of the task is a rough insertion data block a, wherein the data block a contains two types of information, namely position information and process information, and the process information, namely the gripping and releasing signals of the gripper, can be simply abstracted into signal information, namely IO information; the data block A is processed by a coarse insertion task 2T2 and then is stored in a queue B; the data in the queue B is divided into two types of data after being processed by the fine-insertion task T3: positions and events are stored in different queues C and D respectively; position data stored in the queue C, each position data having a strict execution time, such as 4ms, and the task T4 being a strict real-time task, sequentially taking one position data from the queue C and executing the robot (motor) to the position within a prescribed time interval; the queue D stores event data, which includes several basic information, i.e., IO signals, signal trigger mechanisms, and signal trigger delays, the task T5 scans the entire event queue in each scanning cycle, updates the delay (Td) of each event, immediately processes the event once the delay time of the event is up, i.e., processes the signal, and deletes the event from the queue after the processing is completed.

3. The method for improving the working cycle of the robot according to claim 1, wherein the data blocks in the queue B all contain position information and event information, and after the task T3, the position information and the event information are separated into two different queues and are handed to two different tasks for processing; this is because events and locations are not always completely synchronized in processing, and events are classified as:

time event: a certain time interval (Tbe) before reaching the position triggers, which time interval is at least 0;

a location event: triggering when the distance is a certain distance away from the position, wherein the minimum distance is 0;

in the signal processing, the electrical response time (Te) must also be taken into account; the following factors must be considered in calculating the time delay: tbe: time advance, Te: electrical response time, Tq: the execution time of queue C; the calculation formula is as follows: td is Tq-Tbe-Te

Through accurate calculation of the delay time Td, the IO signal is triggered at the moment when the robot arrives at the position, so that the waiting time can be avoided, Tw is reduced to 0, and the beat is effectively improved.

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