Introduction of Soft Growing Robot

Soft Robotics is the specific subfield of robotics involved with constructing robots from soft and compliant materials, similar to those found in living organisms. In IRIS lab, we have been actively researching eversion-based soft robots, inspired from the way plants and vines grow at the tip to achieve movement. Unlike traditional robots, which move through surface contact to walk or run. Our vine robot relies on apical growth for its movement. The robot has a grounded base, and can continually grow as it expands to add material at its tip. The robot is driven by air or water pressure and new material is continuously fed through the body of the robot, which allows the tip to travel orders of magnitude further than other continuum robots. The soft growing robots also have many advantages over fixed length continuum robots. Currently we are working on improving the teleoperation performance of the robot as well as improving the overall design of the robot to allow for better performance and higher payloads with multiple sensors.

Researchers: Nam-Gyun Kim, Dong-Geol Lee, Dong-Oh Seo, ShinWoo Park.

Selected Publications

•  Margaret M. Coad, Laura H. Blumenschein, Sadie Cutler, Javier A. Reyna Zepeda, Nicholas D. Naclerio, Haitham El-Hussieny, Usman Mehmood, Jee-Hwan Ryu, Elliot W. Hawkes and Allison M. Okamura “Vine robots: Design, teleoperation, and deployment for navigation and exploration,” in IEEE Robotics & Automation Magazine, vol. 27, no. 3, pp. 120-132, 2019. [Link]

•  Haitham El-Hussieny, Usman Mehmood, Zain Mehdi, Sang-Goo Jeong, Muhammad Usman, Elliot W. Hawkes, Allison M. Okarnura and Jee-Hwan Ryu, “Development and Evaluation of an Intuitive Flexible Interface for Teleoperating Soft Growing Robots,” in 2018 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS). [Link]

•  Haitham El-Hussieny, Ibrahim A. Hameed and Jee-Hwan Ryu, “Nonlinear Model Predictive Growth Control of a Class of Plant-Inspired Soft Growing Robots”, in IEEE Access, vol. 8, pp. 214495 -214503, 2020. [Link]

A Tip Mount for Transporting Sensors and Tools using Soft Growing Robots

Pneumatically operated soft growing robots that extend via tip eversion are well-suited for navigation in confined spaces. Adding the ability to interact with the environment using sensors and tools attached to the robot tip would greatly enhance the usefulness of these robots for exploration in the field. However, because the material at the tip of the robot body continually changes as the robot grows and retracts, it is challenging to keep sensors and tools attached to the robot tip during actuation and environment interaction. In this paper, we analyze previous designs for mounting to the tip of soft growing robots, and we present a novel device that successfully remains attached to the robot tip while providing a mounting point for sensors and tools.  Our tip mount incorporates and builds on our previous work on a device to retract the robot without undesired buckling of its body. Using our tip mount, we demonstrate two new soft growing robot capabilities: (1) pulling on the environment while retracting, and (2) retrieving and delivering objects. Finally, we discuss the limitations of our design and opportunities for improvement in future soft growing robot tip mounts.

    Researchers: Sang-Goo Jeong, Ji-hun Kim.

    Publications

    •  Sang-Goo Jeong, Margaret M. Coad, Laura H. Blumenschein, Ming Luo, Usman Mehmood, Ji Hun Kim, Allison M. Okamura and Jee-Hwan Ryu. “A Tip Mount for Transporting Sensors and Tools using Soft Growing Robots”, 2020 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS). [Link]

    Origami-inspired New Material Feeding Mechanism for Soft Growing Robots to Keep the Camera Stay at the Tip by Securing its Path

    Soft growing robots that extend through tip eversion have attracted considerable interest owing to their unique locomotion. Although the availability of visual feedback from the tip of such robots would greatly enhance their usefulness in field explorations, given that the material at the tip continually moves as the robot grows, mounting a camera at the tip of the robot and securing it in place during robot growth has been a major challenge. Previous designs have severely impeded these robots’ intrinsic advantages, and it remains challenging to ensure that the camera remains at the tip without encumbering the robots’ natural ability to morph its shape and grow along or over an obstacle. In this letter, for the first time, we propose a method to maintain the camera at the tip during robot growth, while retaining the compliant nature of the robot. 

      An origami-inspired new material feeding mechanism is designed to secure the camera’s path from the base to the tip, which allows us to control the camera’s growing speed independently of the robot. We experimentally investigate the required control parameters and present a vision-based control method for camera position adjustment. Finally, we demonstrate the feasibility of the proposed design in simulated experimental scenarios, including a narrow passage and a cluttered environment.

      Researchers: Ji-hun Kim, Jaehyung Jang, Sang-min Lee, Sang-Goo Jeong.

      Publications

      •  Ji-Hun Kim, Jaehyung Jang, Sang-min Lee, Sang-Goo Jeong Yong-Jae Kim and Jee-Hwan Ryu, “Origami-inspired New Material Feeding Mechanism for Soft Growing Robots to Keep the Camera Stay at the Tip by Securing its Path,” in IEEE Robotics and Automation Letters, vol. 6, no. 3, pp. 4592-4599, 2021. [Link]

      Researchers

      Nam-Gyun Kim, Ph.D student, Group leader, Contact: nam96bird@kaist.ac.kr

      Dong-Geol Lee, Ph.D student.

      Dong-Oh Seo, Master student.

      ShinWoo Park, Master student.