MAE Seminar – Mobility and Manipulation Using Soft and Tensegrity Modular Robots

Details

MAE Seminar – Mobility and Manipulation Using Soft and Tensegrity Modular Robots

Thursday, February 8, 2024, at 12:50pm, Location: MAE-A 303

Dr. Vishesh Vikas, Associate Professor, Department of Mechanical Engineering, University of Alabama

Abstract
Modularity, symmetry and repetitiveness, observed in nature, have inspired the design of reconfigurable rigid-robots. The use of soft materials and tensegrity principles in modular systems has potential to further enhance their versatility, robustness and lower economic cost. Soft materials are highly deformable (stretch, distort), adaptable (rich interaction with the environment), impact resistant, and safe-to-operate around humans. Contrastingly, tensegrity mechanisms synergistically combine elements in tension (cables) and compression (rigid rods) to ensure structural integrity – imparting them with a high strength-to-weight ratio. The talk will discuss design and control of modular robots based on these principles – spherically reconfigurable modular soft robots (MSoRos) capable of performing terrestrial locomotion, and a dexterous continuum tensegrity manipulator (DexTeR). The design methodology for MSoRos allow for them to exist in multiple modes – millipede-like 1D, starfish-like planar and soccer-ball-like spherical. This dimensional change alters the locomotion dynamics and can help in maneuvering variable terrains. The control of such soft robots requires addressing problems of gait definition (how to mathematically define a gait, e.g., crawl or inch?), gait synthesis and exploration (how to determine and evaluate the underlying useful gaits?) and gait characterization (what type of gait are they, e.g., rotation or translation?). The discussed probabilistic Model-Free Framework (pMFC) is a data-driven approach that constructs a diverse set of open-loop gaits. This morphology-agnostic method directly encodes robot-environment interactions, and accounts for manufacturing inaccuracies, overcoming challenges of current model-based methods. The continuum manipulator, DexTeR, is inspired by the human spine and consists of ten (10) serially connected vertebrae modules. Each module comprises two rigid elements joined together by twelve (12) strings using principles of tensegrity where the rigid elements do not touch.

Biography
Vishesh Vikas is an Associate Professor in Mechanical Engineering at University of Alabama, Tuscaloosa where he directs the Agile Robotics Lab (ARL) since 2016. He received his B.Tech from IIT Guwahati, and MS and PhD in Mechanical Engineering from University of Florida, Gainesville. He currently serves as the Associate Editor of ASME Journal of Mechanisms and Robotics (JMR), Robotics Reports and secretary of the ASME DSCD technical committee. In past, he has served as chair of Student Mechanisms Robotics and Design Competition (SMRDC) at the ASME International Design Engineering Technical Conferences & Computers and Information in Engineering Conference (IDETC). He has been actively involved with workshop and outreach efforts with regard to Mechatronics and Robotics Education (MRE). His research interests include soft robotics, tensegrity mechanisms, bio-inspired robotics, sensor fusion, robot modeling and control, and dynamical systems.

MAE Faculty Host: Dr. Jane Shin