Gravity-Assisted Shape-Locking Articulated Discrete Serial Robot for Ceiling-Mounted Manipulation in Patient Care
Seonhun Lee, Frank Sup IV
AI summary
Problem
Existing ceiling lifts lack configurability and floor-based assistive robots pose safety and workflow challenges in crowded patient rooms, while continuum robots suffer from low stiffness and payload limits.
Approach
The authors designed a ceiling-mounted articulated serial robot that switches between a passive, chain-like mode for gravity-aligned deployment and an active mode where joints are friction-locked for rigid manipulation, validated on a reduced-scale prototype.
Key results
- High positional repeatability across 300 point-to-point iterations
- Silhouette scores up to 0.984 confirming accurate target clustering
- Successful validation of friction-based shape-locking under load
- Demonstrated feasibility of gravity-assisted actuation for ceiling-mounted manipulation
Why it matters
Provides a scalable, floor-space-saving robotic architecture that can reduce physical strain on nursing staff and enhance direct patient care workflows.
Abstract
Continuum robots are promising for assistive manipulation, but often lack the stiffness and payload ca- pacity required for real-world tasks. This paper investigates the feasibility of a novel dual-mode, gravity-assisted ceiling- mounted articulated discrete serial robot that transitions be- tween passive and active states using a friction-based shape- locking mechanism. In passive mode, joints are unlocked, allowing for chain-like flexibility similar to that of ceiling hoists. In active mode, joints are locked, allowing for rigid and accurate manipulation. To evaluate feasibility, we implemented a reduced-scale prototype with two passive joints and one active joint. We tracked its accuracy across 300 iterations of point-to- point motion in a 2D plane. Results show high repeatability and robustness, highlighting the potential of this architecture for ceiling-mounted manipulation. Beyond healthcare tasks such as patient handling, this approach contributes a scalable actuation and shape-locking strategy for articulated discrete serial robots in constrained environments.