Design of surface wave active beds based on human tissue physiology

A surface wave distributed actuation method and its proper design for safel y transporting bedridden patients is explored in this paper. First. the bas ic principle of surface wave distributed actuation is presented, including a new kinematic feature that augments natural surface wave motion for enhan ced transport efficiency of humans and elastic bodies, Kinematic modeling a nd analysis reveals that an object can be transferred by a simplified actua tor 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 i nteraction. Static models are developed and solved using finite element met hods to calculate interaction stresses for realistic, worst-case human-surf ace wave interaction scenarios. Based on these results a new two-mode surfa ce is designed to secure safe interactions for both long-term support and s hort term transport tasks.