Design of surface wave active beds based on human tissue physiology
Abstract:A surface wave distributed actuation method and its proper design for safely transporting bedridden patients is explored in this paper. First, the basic principle of surface wave distributed actuation is presented, including a new kinematic feature that augments natural surface wave motion for enhanced transport efficiency of humans and elastic bodies. Kinematic modeling and analysis reveals that an object can be transferred by a simplified actuator architecture that makes the concept amenable to hardware realization. A proof of concept prototype demonstrates that heavily loaded rigid objects, elastic objects and humans can be transported. Human tissue physiology is studied to establish worst-case criteria for safe and healthy interactions between the human and the support surface that depends on the duration of interaction. Static models are developed and solved using finite element methods to calculate interaction stresses for realistic, worst-case human-surface wave interaction scenarios. Based on these results a new two-mode surface is designed to secure safe interactions for both long-term support and short term transport tasks.
Document Type: Research Article
Affiliations: 1: d'Arbeloff Laboratory for Information Systems and Technology, Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA 2: d'Arbeloff Laboratory for Information Systems and Technology, Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
Publication date: February 1, 2001