Robot Controller for Stable Orientation Control via Intersecting Axes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing robot control methods using direct teaching with force application struggle to stably change the orientation of a robot's end effector and move each axis to a desired position on an orthogonal coordinate system, as they either result in unstable orientation changes or limit movement directions, failing to effectively manage both positional and orientational adjustments.
Innovation Solution
A robot controller system that includes a force measuring part, a control point specifying part, and an operation commanding part, which calculates and outputs commands for rotational and translational movements based on forces applied to a control coordinate system, allowing stable orientation changes and axis positioning by intersecting rotation axes at a common origin, enabling efficient movement of a vertical multi-joint robot with three or more axes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If direct teaching is used to move the robot by applying force to the front end, then the robot can be moved to a desired position, but the orientation change becomes unstable
Solution Approach 1:
The patent introduces a force calculating part as an intermediary that processes the raw force signal from the force measuring part. This intermediary calculates the force on the control coordinate system at the control point, transforming the direct force application into a controlled rotational movement about the control point, thereby stabilizing the orientation change while maintaining positioning accuracy
2Device complexity
If the robot is configured with three or more rotation axes intersecting at a common origin, then the control complexity is reduced, but the structural design becomes more constrained
Solution Approach 1:
The patent changes the geometric parameters of the robot structure by configuring three or more rotation axes to intersect at a common origin (the control point). This parameter change in the structural design simplifies the control calculations and reduces control complexity, as the force calculation and movement control become more straightforward with the intersecting axes configuration
3Speed
If force control responsiveness is increased to improve movement responsiveness, then the robot responds faster to applied force, but the orientation change becomes unstable
Solution Approach 1:
The patent implements a feedback mechanism where the force calculating part continuously calculates the force on the control coordinate system based on the measured force, and the operation commanding part uses this calculated force to generate rotational movement commands. This closed-loop feedback approach allows for responsive movement while maintaining orientation stability through proper force calculation and control
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution allows for stable and precise control of a robot's orientation and axis positioning, reducing the number of axes that need to be simultaneously controlled, thereby enhancing operational stability and ease of movement, while enabling the robot to change orientation and move axes to desired positions effectively.
Implementation Method 1
a force sensor that detects a force applied to a front end of the robot arm
Data Source
AI summary
A robot controller and a robot system capable of stably changing the orientation of a front end of a robot by applying a force to the front end, and moving each axis to a desired position. The robot controller for moving the robot based on the force applied to the robot includes a control point specifying part which specifies a control point in relation to the robot, and an operation commanding part which outputs a command so that the robot performs rotational movement about the control point. The robot has a structure constituted by sequentially combining three or more axes including at least three rotation axes, and rotation centerlines of the three rotation axes intersect at an origin of a centerline-intersecting axis, the centerline-intersecting axis corresponding to one of the three rotation axes. The control point specifying part specifies the origin of the centerline-intersecting axis as the control point.