ROKAE xMate CR7, Руководство по установке оборудования

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202206291217/V0.1
8 Zero Calibration
xMate CR7Hardware Installation Manual 45
8 Zero Calibration
8.1 Introduction
8.1.1 Overview
This section describes the zero calibration. Use the calibration tools described in this section
during calibration.
8.1.2 What is a mechanical zero?
The robot is pre-defined with an initial pose during its design, in which the angle of each joint
is zero. From a mechanical viewpoint, the zero pose is the pose where a certain angle is
formed between adjacent links. From a software viewpoint, since the robot uses the encoder
to record the joint angle, the zero pose refers to the robot's pose when the servo motor
rotates to a certain encoder value. Therefore, the mechanical zero can be explained in two
ways:
⚫
From the perspective of the observer, the mechanical zero is the robot's pose when
each joint of the robot moves to a certain position.
⚫
From the perspective of the control system, the mechanical zero is a combination of
encoder values.
8.1.3 What is zero calibration?
The zero point is a point of reference for the robot coordinate system. It is required for the
robot to determine its own position. To maximize the absolute positioning accuracy and
allow the link system to properly respond to the position and speed instructions from the
control system, a zero calibration must be performed on the robot to bring the mechanical
zero as close to the algorithm zero as possible.
Put simply, zero calibration is the process of using the pre-designed positioning devices on
the mechanical arm body to rotate the joints of the robot to a certain angle, and notifying the
control system to record the value of each joint motor encoder.
8.1.4 When is zero calibration required?
8.1.4.1
When the mechanical transmission system fails to operate properly
A zero calibration must be performed using dedicated calibration tools in the following
circumstances:
⚫
After replacing mechanical system parts such as motors and reducers;
⚫
After a violent collision;
⚫
When moving the robot joints manually after the control system is switched off.
8.1.4.2
When the multi-turn counter data of the encoder is lost
A zero calibration can be performed using dedicated calibration tools in the following
circumstances:
⚫
After reinstalling the entire hard disk system;