Hello! I am Yichen Zhai, a Postdoctoral Scholar at UC San Diego, working with Prof. Michael Tolley. My research focuses on developing one-shot 3D printing strategies for creating autonomous, air-powered soft robots that require no electronics or assembly. My long-term goal is to establish an automated and accessible framework that unifies design, materials, and manufacturing, enabling functional robots to emerge directly from digital models, ready for real-world applications.

I received my Ph.D. in Electrical and Computer Engineering from UC San Diego under Prof. Tse Nga (Tina) Ng, where I developed multi-material 3D printing methods for soft and functional materials such as liquid crystal elastomer (LCE), thermoplastic polyurethane (TPU), silicone gel, and silver conductor ink. These works linked material morphology, processing parameters, and functional performance, demonstrating how fabrication itself can encode actuation and control.

My research interests include soft robotics, additive manufacturing, pneumatic systems, and embodied intelligence, with applications in autonomous locomotion, manipulation, and interactive devices. I am always open to discussions and collaborations in robot design, digital fabrication, and intelligent materials.

Research Highlights

Monolithically Printed Electronics-free Autonomous Walking Robot

A soft robot was printed in one piece from a single material using an affordable FDM printer. After printing, it required no manual assembly. Powered by a constant air-pressure supply, it could walk immediately. With no electronic components, it was able to operate safely in aquatic environments.

One-shot Printed Air-powered Autonomous Soft Gripper

I developed an approach to design and 3D print soft airtight structures for robotic devices with pneumatic intelligence. A soft robotic gripper was demonstrated to show the fabrication process and operation. Powered by an air-pressure supply, it could grasp objects upon contact and release them when turned horizontally.

3D-printed Tadpole-inspired Swimming Robots

Demonstration of 3D-printed untethered swimming robots powered by CO₂ canisters. The onboard four-phase pneumatic oscillators controlled their undulating swimming gaits.

3D-Printed Liquid Crystal Elastomer (LCE) Film for Surface Morphing

A multi-layer LCE film was fabricated using a 3D printer with programmed mesogen alignments to achieve precise, localized bending actuations across the entire film upon heating. This was demonstrated by reproducing a human face from a flat film.

3D-Printed Light-Driven Crawler Powered by LCE Actuators

A crawler powered by LCE actuators with embodied physical intelligence was demonstrated. A flapping shade on the robot autonomously covered one side of the LCE while exposing the other side to light radiation to absorb heat energy. The alternating actuation of the LCE actuators generated cyclic motion and propelled the robot forward.

© 2025 Yichen Zhai | University of California, San Diego

Last updated: November 2025