Session: 02-10-01: Session #1: Robotics and Automation in Advanced Manufacturing

Paper Number: 93929

93929 - Prototype Design and Manufacture of a Deployable Tensegrity Microrobot 

Micro-, and milli-scale robots have been of great R&D interest for minimal invasive diagnosis and treatment in the past several decades. Recent minimal invasive interventions call for robots that work as tiny “surgeons" or drug delivery “vehicles" to achieve inner body diagnostic, surgical, and therapeutic practices, without any trauma or discomfort. A good solution to this design need is an milli-scale deployable tensegrity microrobot, which is made of a deployable tensegrity structure integrated by self-stress. The microrobot can be folded to only 15% of its deployed length, so as to easily enter a desired working area with a small entrance. When deployed, the tensegrity body of the robot displays lightweight and high stiffness to sustain loads and prevent damages when burrowing through tightly packed tissues or high-pressure environments. A locomotion of the tensegrity microrobot is designed to mimic a crawling motion of an earthworm, which grants the robot an ability to move well through small working areas. This microrobot is untethered, as it is powered by electrical magnetic field.

An essential component in development of such a deployable tensegrity microrobot is its prototype design and manufacture. Traditional tensegrity robot manufacturing techniques were based on manually assembling of members and/or parts. Because they were developed to build large robot bodies. These manually assembling based manufacturing techniques could potentially create an obstacle of achieving a micro-, or milli-scale body size with complex topology and high shape accuracy. A loss of high shape accuracy may deteriorate the robot’s locomotion efficiency, or cause failure of deployment. In addition, traditional prototype designs of tensegrity robots were mostly approached by topology design and form finding, which are theory oriented. An issue of these prototype design approaches is the lack of incorporation of micro-structures manufacture and locomotion planning, which may further downgrade locomotion efficiency of the microrobot.

To fill afore-mentioned technical gap, a framework that incorporates prototype design and micro-structure manufacture of a deployable tensegrity microrobot is proposed in this paper. In this framework, the issue of losing shape accuracy traditional tensegrity robot manufacturing techniques shall be solved by using a fused deposition modelling advanced additive manufacturing or 3-D printing system, equipped with multi-head extruders to allow the use of different materials in a single structural printing procedure. Thus, a high structure shape accuracy can be achieved by avoiding manually assembling of the microrobot body.  In addition, topology, locomotion and structural materials of the microrobot shall be determined optimally, so as to facilitate the use of the advanced additive manufacturing technique. The proposed framework for prototype design and manufacture are applied in development of a five-unit deployable tensegrity microrobot. Effectiveness of the framework shall be proved in both numerical simulations and experiments.

Presenting Author: Sichen Yuan Lawrence Technological University

Presenting Author Biography: Dr. Sichen Yuan is an Assistant Professor in A. Leon Linton Department of Mechanical, Robotics and Industrial Engineering at Lawrence Technological University. He received his Ph.D. and Master's degree in mechanical engineering at University of Southern California in 2019 and 2014, respectively. He received his Bachelor's degree in mechanical engineering at Shanghai Jiao Tong University in 2012. His research interests include computational solid mechanics, dynamics and control, vibrations of deployable structures, robotics and deep learning.

Authors:

Christian Kazoleas Lawrence Technological University
Kaushik Mehta Lawrence Technological University
Sichen Yuan Lawrence Technological University