For robots to be useful for real-world applications, they must be safe around humans, be adaptable to their environment, and operate in an untethered manner. Soft robots could potentially meet these requirements; however, existing soft robotic architectures are limited by their ability to scale to human sizes and operate at these scales without a tether to transmit power or pressurized air from an external source. In this project, we have developed an untethered, inflated robotic truss, composed of thin-walled inflatable tubes, capable of shape change by continuously relocating its joints, while its total edge length remains constant. A set of identical roller modules each pinch the tube to create an effective joint that separates two edges, and modules can be connected to form complex structures. Driving a roller module along a tube changes the overall shape, lengthening one edge and shortening another, while the total edge length and hence fluid volume remain constant. This isoperimetric behavior allows the robot to operate without compressing air or requiring a tether. Our concept brings together advantages from three distinct types of robots—soft, collective, and truss-based—while overcoming certain limitations of each. Our robots are robust and safe, like soft robots, but not limited by a tether; are modular, like collective robots, but not limited by complex subunits; and are shape-changing, like truss robots, but not limited by rigid linear actuators. With the same collective of robots we can construct a variety of truss structures including two-dimensional (2D) robots capable of shape change and a human-scale 3D robot capable of punctuated rolling locomotion and manipulation.
Publications
- Hammond, Z. M. & Follmer, S. (2021). Grasp analysis and manipulation kinematics for isoperimetric truss robots. In Press.
- Stuart, A. D., Hammond, Z. M., & Follmer, S. (2021). Balloon animal robots: Reconfigurable soft robots. In Preparation.
- Hammond, Z. M. & Follmer, S. (2021). Pneumatic reel actuator: A variable stiffness, high-extension, pneumatic actuator. In Preparation.
- Usevitch, N. S.*, Hammond, Z. M.*, Schwager, M., Okamura, A. M., Hawkes, E. W., & Follmer, S. (2020). An untethered isoperimetric soft robot. Science Robotics, 5(40). [VIEW]
(*) These authors contributed equally. - Usevitch, N. S., Hammond, Z. M., & Schwager, M. (2020). Locomotion of linear actuator robots through kinematic planning and nonlinear optimization. IEEE Transactions on Robotics, 36(5), 1404-1421. [VIEW]
- Slade, P., Gruebele, A., Hammond, Z., Raitor, M., Okamura A. M., & Hawkes, E. W. (2017, September). Design of a Soft Catheter for Low-Force and Constrained Surgery. In IEEE/RSJ International Conference on Intelligent Robots and Systems. 2017 [VIEW]
- Usevitch, N., Hammond, Z., Follmer, S., & Schwager, M. Linear Actuator Robots: Differential Kinematics, Controllability, and Algorithms for Locomotion and Shape Morphing. (2017, September) In IEEE/RSJ International Conference on Intelligent Robots and Systems. 2017 [VIEW]
- Hammond, Z. M., Usevitch, N. S., Hawkes, E. W., & Follmer, S. (2017, May). Pneumatic Reel Actuator: Design, modeling, and implementation. In Robotics and Automation (ICRA), 2017 IEEE International Conference on (pp. 626-633). IEEE. [VIEW]
- Hammond, Z. M., Mack, J. H., & Dibble, R. W. (2016). Effect of hydrogen peroxide addition to methane fueled homogeneous charge compression ignition engines through numerical simulations. International Journal of Engine Research, 17(2), 209-220. [VIEW]
Presentations
- “A soft, untethered isoperimetric robot.” Presentation and poster at Bay Area Robotics Symposium, Berkeley, CA, November 2019.
- “A soft, untethered isoperimetric robot.” Poster at System X Conference, Berkeley, CA, November 2019.
- “Variable stiffness linear actuator robot.” Presentation and poster at 2018 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Madrid, Spain, October 2018.
- “Assistive device for rock climbing with soft actuators.” Poster at the Stanford Mechanical Engineering Research Conference, Stanford, CA, 2016.
- “The addition of hydrogen peroxide to methane fueled homogeneous charge compression ignition engines through numerical simulation.” Presentation at ASME Undergraduate Research Symposium, Dearborn, MI, October 2013.
- “Vibration characterization and attenuation of noise on a table-top extreme ultra-violet laser.” Presentation at NSF REU Symposium, Boulder, CO, August 2013.
Selected Press
- Stanford engineers create shape-changing, free-roaming soft robot (March 18, 2020). Stanford News.
- Soft Robot, Unplugged (March 18, 2020). The Current.
- Stanford Makes Giant Soft Robot From Inflatable Tubes (March 18, 2020). IEEE Spectrum.
- Watch robot change its shape like a ‘Transformer’ (March 20, 2020). CNN.
- This shape-shifting soft robot can perform multiple functions (April 1, 2020). Medium.
- Stanford’s shape-shifting ‘balloon animal’ robot could one day explore space (March 25, 2020). Digital Trends.
- A “Human-Scale Soft Robot” Could Make Deliveries in a Quarantine (March 19, 2020). Inverse.
- Baymax on Mars? Shapeshifting ‘Soft’ Robot Could [Literally] Transform Planet Exploration (March 18, 2020). Syfy.
- New robot developed at Stanford changes shape like a ‘Transformer’ (March 21, 2020). TechRepublic.
- Shape-changing inflatable robot can nab objects and roam on its own (March 18, 2020). New Atlas.
- Researchers Create Soft Robot Able to Change Shape and Roam (March 19, 2020). Unite AI.
- Stanford engineers create a new robot that combines traditional and soft robotics (March 19, 2020). SlashGear.
- Stanford Engineers Create Inflatable, Shape-Shifting Soft Robot (March 23, 2020). Core 77.
- Leinen los für aufblasbare Roboter (March 18, 2020). heise.
- 科学家研发可变形充气机器人 可以抓取物体并自行漫游 (March 19, 2020). cnBeta.
- Realizzato un soft robot che cambia sembianze a seconda delle esigenze (March 19, 2020). RSVN.
- Инженеры создали мягкого робота, способного менять форму во время движения (March 19, 2020) Хайтек.
- «Детали» c Андреем Деркачем (June 2020) Voice of America, Russian Service
- And more