Characterization and Evaluation of Screw-Based Locomotion across Aquatic, Granular, and Transitional Media
Derek Chen, Zoe Samuels, Lizzie Peiros, Sujaan Mukherjee, Michael C. Yip
AI summary
Problem
Traditional screw design models fail to predict locomotion performance across multi-modal environments, leaving a critical gap in optimizing amphibious robots for transitional zones like wet sand or saturated soil.
Approach
The authors systematically tested multiple screw configurations across water, dry sand, wet sand, and saturated sand, introducing derived performance metrics inspired by heat sink optimization and terra-mechanics to better predict locomotion efficiency.
Key results
- Blade height dominates performance in granular media, while pitch angle drives efficiency in water
- Derived metrics like aspect ratio and tip speed correlate better with locomotion than traditional engineering parameters
- High pitch angles cause digging and poor traction in sand due to lack of material refilling
- Rolling locomotion serves as a necessary alternative strategy in saturated, non-Newtonian transitional media
Why it matters
This framework enables the design of more reliable amphibious robots for hazardous, multi-terrain environments like lava tubes and marshlands where traditional single-medium models fail.
Abstract
Screw-based propulsion systems offer promising capabilities for amphibious mobility, yet face significant chal- lenges in optimizing locomotion across water, granular ma- terials, and transitional environments. This study presents a systematic investigation into the locomotion performance of var- ious screw configurations in media such as dry sand, wet sand, saturated sand, and water. Through a principles-first approach to analyze screw performance, it was found that certain param- eters are dominant in their impact on performance. Depending on the media, derived parameters inspired from optimizing heat sink design help categorize performance within the dominant design parameters. Our results provide specific insights into screw shell design and adaptive locomotion strategies to enhance the performance of screw-based propulsion systems for versatile amphibious applications.