Robot Hand Holding Posture Selection Using a Manipulability Map
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing robotic handling systems face challenges in gripping objects of various shapes, sizes, and weights due to limitations in the range of possible postures and accessible regions, particularly when using suction pads, which restrict the movement and positioning of robot hands.
Innovation Solution
A handling device with a controller that generates holdable candidate points and determines holding postures based on a manipulability map, which associates each position in the environment with a parameter calculated from joint angles, allowing for improved accessibility and posture selection using a manipulability map to enhance the handling of objects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a robot hand is offset to access restricted regions, then accessibility to restricted regions is improved, but link length increases causing limitations in range of possible postures
Solution Approach 1:
The system pre-calculates and stores optimal holding positions and postures in a lookup table before actual operation. This allows the robot to quickly retrieve pre-determined solutions for accessing restricted regions without real-time computation, maintaining both accessibility and posture flexibility.
Solution Approach 2:
A computer serves as an intermediary between the control device and the robot hand, managing the complex calculations and storing posture information in a lookup table. This intermediary handles the computational burden, allowing the robot hand to focus on execution while maintaining full range of motion capabilities.
2Measurement precision
If multiple holding positions and postures are calculated in real-time, then holding plan accuracy is improved, but processing time increases
Solution Approach 1:
The system performs the computationally intensive calculation of multiple holding positions and postures in advance, storing results in a lookup table. During actual operation, the system simply retrieves pre-calculated data, achieving both high accuracy and fast processing without real-time computation delays.
Solution Approach 2:
The lookup table acts as a buffer prepared in advance, cushioning against real-time processing requirements. By having all possible holding solutions pre-computed and stored, the system eliminates the need for time-consuming real-time calculations while maintaining comprehensive holding plan accuracy.
3Device complexity
If a single suction pad is used for small lightweight workpieces, then device complexity is reduced, but the range of accessible regions is limited
Solution Approach 1:
The system pre-calculates multiple holding positions that a single suction pad can achieve, storing these positions in a lookup table. This allows a simple single-pad end effector to access multiple restricted regions by retrieving pre-determined positions, maintaining both device simplicity and extended accessibility.
Solution Approach 2:
The single suction pad is designed to perform multiple functions by accessing different pre-calculated holding positions for various restricted regions. Through the lookup table system, one simple pad structure achieves the versatility of multiple pads by knowing where to position itself for different tasks.
Data Source
AI summary
A handling device according to an embodiment has an arm, a holder, a storage, and a controller. The arm includes at least one joint. The holder is attached to the arm and is configured to hold an object. The storage stores a function map including at least one of information about holdable positions of the holder and information about possible postures of the holder. The detector is configured to detect information about the object. The controller is configured to generate holdable candidate points on the basis of the information detected by the detector, to search the function map for a position in an environment in which the object is present, the position being associated with the generated holdable candidate points, and to determine a holding posture of the holder on the basis of the searched position. The function map associates a manipulability with each position in the environment in which the object is present. The manipulability is a parameter calculated from at least one joint angle of the holder.