Robot Hand With Rotatable Holding Pads and Pressing Member
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing robot hands with paired main fingers and an auxiliary finger struggle to efficiently hold and manipulate workpieces with varying orientations, as they require significant surface pressure and rigidity to counteract rotational moments, leading to oversized and rigid finger structures.
Innovation Solution
A hand system with a pair of finger members that are relatively movable, equipped with rotatable holding pads and a pressing member that moves in a direction intersecting the radial axis, allowing the holding pads to press the workpiece from both sides and adjust its attitude using a cam follower, which reduces friction and moment transfer, enabling precise control and downsizing of the finger members.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the main fingers are made larger and more rigid to counteract rotational moments, then the holding stability is improved, but the device size and structural complexity increase
Solution Approach 1:
The finger structure is segmented into multiple functional components: a finger body for positioning, a holding pad for contact, and a pressing member for attitude control. This segmentation allows each component to be optimized independently, reducing overall complexity while maintaining holding stability through the coordinated action of these specialized segments.
Solution Approach 2:
The holding pad acts as an intermediary between the finger body and the workpiece, providing a dedicated contact interface that can rotate independently. This intermediary structure absorbs rotational moments without requiring the entire finger structure to be oversized and rigid, thus maintaining holding stability while reducing device complexity.
2Stability of the object's composition
If the finger members are made more rigid to maintain workpiece attitude, then the attitude control is improved, but the device size and weight increase
Solution Approach 1:
The holding pad is designed to rotate around an axis extending in the interval direction, transforming the rigid finger structure into a dynamic system. This rotational capability allows the holding pad to adapt to workpiece orientation changes without requiring increased finger member weight, maintaining attitude control through controlled movement rather than rigid resistance.
Solution Approach 2:
The pressing member is positioned at a location separated from the rotation axis in the radial direction, creating a moment arm that amplifies its effect. This dimensional arrangement allows a smaller, lighter pressing member to generate sufficient rotational moment for attitude control, avoiding the need for heavier finger structures.
3Stress or pressure
If the holding pads are made larger to increase contact area, then the surface pressure distribution is improved, but the device size increases
Solution Approach 1:
The holding pad surface features a pressing portion with a specific shape that concentrates contact area, and the pressing member applies localized pressure to this region. By changing the pressure distribution parameters through geometric design rather than increasing overall pad size, the system achieves improved surface pressure distribution while minimizing volume.
Data Source
AI summary
A hand includes a pair of finger members disposed separated by an interval and relatively movable in an interval direction, a finger drive unit that moves at least one of the finger members in the interval direction, a pair of holding pads that are provided on the respective finger members, and are supported to face each other and to be rotatable around an axis extending in the interval direction, and a pressing member that is provided to be movable in a direction intersecting a radial direction, at a position separated from the axis in the radial direction, and presses a surface of a workpiece held between the holding pads.