Session: 16-01-01: Government Agency Student Poster Competition

Paper Number: 150446

150446 - Contact Based Navigation and Compact Actuation Unit Design for Concentric Tube Robots for Structural Integrity Assessment 

Concentric Tube Robots (CTRs) traditionally have been explored extensively for medical applications such as minimally invasive surgery, with a maximum length found in the literature of approximately 200mm. The primary objective of our novel design approach is to modify and adapt these robots for industrial applications, extending the fully elongated length to approximately 1 meter. This advancement aims to surpass the capabilities of conventional borescopes and other commercially available devices that are currently being used for structural integrity inspections and assessments. The new design allows for the inspection and delivery of components such as sensors, conductors, and other parts, as well as performing tasks like spray coating and wire harnessing in places that are currently hard-to-reach or inaccessible. Depending on the specific task, various tools can be attached to the robot's end effector, broadening its range of applications. Unlike their medical counterparts, which try to avoid direct contact with the surrounding environment, for our industrial version of these robots we intentionally introduce contact forces to better navigate challenging pathways. By leveraging the contact and friction forces from the environment, innovative locomotion strategies can be developed and implemented. The testing phase provided valuable insights, leading to the development of a new “grab and pull” locomotion strategy that utilizes the induced environmental friction. Success and failure data were collected in a single bent testing curriculum for various turns with angles ranging from 45° to 135°, in increments of 5°, under three different environmental relative friction levels: low, medium, and high. The selected tube sizes and curvature values provided a high success rate in the controlled testing environment.  A micro camera as well as a fiber optic sensor (FBG) was implemented on the robot to improve and enhance the situational awareness of the operator and the reconstructed data from the nested fiber optic sensor showed promising results in measuring and predicting the final shape of the tubes. Attempts to create a handheld miniaturized version of the robot demonstrated the feasibility of actuating the tubes in a “coiled-tubing” configuration, allowing weight saving and the robot to achieve a more compact design that can be moved around the industrial setup conveniently. A subsequent phase of the project involves fabricating and assembling a motorized handheld version of the robot. Overall and despite the positive results, several design parameters require further investigation and remain unsolved, including the relative size of the robot and environment, as well as refining the optimal tube size and curvature values, to achieve the necessary turning angles within the highly congested working environment.

Presenting Author: Parsa Molaei Louisiana State University

Presenting Author Biography: Parsa Molaei obtained his Bachelor of Science in Mechanical Engineering from Sharif University of Technology in the Spring of 2018. He began his doctoral research in the Department of Mechanical and Industrial Engineering at Louisiana State University in Baton Rouge, USA. He worked in the Innovation in Control and Robotics Engineering (iCORE) Lab as a graduate researcher focusing on the stability of soft/continuum robots. He earned a Master of Science degree in Mechanical Engineering in the Spring of 2023 while continuing his doctoral research.

Authors:

Parsa Molaei Louisiana State University
Velshunti Thompson Louisiana State University
Jyotsna Sharma Louisiana State University
Hunter Gilbert Louisiana State University