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Chengyi Xu

Publications and source records attributed to Chengyi Xu.

4 recordsLinked to original sources

Multimodal Machine Learning for Soft High-k Elastomers under Data Scarcity

Dielectric materials are critical building blocks for modern electronics such as sensors, actuators, and transistors. With rapid advances in soft and stretchable electronics for emerging human- and robot-interfacing applications, there is a growing need for high-performance dielectric elastomers. However, developing soft elastomers that simultaneously exhibit high dielectric constants (k) and low Young's moduli (E) remains a major challenge. Although individual elastomer designs have been reported, structured datasets that systematically integrate molecular sequence, dielectric, and mechanical properties are largely unavailable. To address this gap, we curate a compact, high-quality dataset of acrylate-based dielectric elastomers by aggregating experimental results from the past decade. Building on this dataset, we propose a multimodal learning framework leveraging large-scale pretrained polymer representations. These pretrained embeddings transfer chemical and structural knowledge from vast polymer corpora, enabling accurate few-shot prediction of dielectric and mechanical properties and accelerating data-efficient discovery of soft high-$k$ dielectric elastomers. Our data and implementation are publicly available at: https://github.com/HySonLab/Polymers

cs.LG

DexSkin: High-Coverage Conformable Robotic Skin for Learning Contact-Rich Manipulation

Human skin provides a rich tactile sensing stream, localizing intentional and unintentional contact events over a large and contoured region. Replicating these tactile sensing capabilities for dexterous robotic manipulation systems remains a longstanding challenge. In this work, we take a step towards this goal by introducing DexSkin. DexSkin is a soft, conformable capacitive electronic skin that enables sensitive, localized, and calibratable tactile sensing, and can be tailored to varying geometries. We demonstrate its efficacy for learning downstream robotic manipulation by sensorizing a pair of parallel jaw gripper fingers, providing tactile coverage across almost the entire finger surfaces. We empirically evaluate DexSkin's capabilities in learning challenging manipulation tasks that require sensing coverage across the entire surface of the fingers, such as reorienting objects in hand and wrapping elastic bands around boxes, in a learning-from-demonstration framework. We then show that, critically for data-driven approaches, DexSkin can be calibrated to enable model transfer across sensor instances, and demonstrate its applicability to online reinforcement learning on real robots. Our results highlight DexSkin's suitability and practicality for learning real-world, contact-rich manipulation. Please see our project webpage for videos and visualizations: https://dex-skin.github.io/.

cs.RO

A Giant, High-frequency Oscillation of Metal Strip Actuator under DC Electric Field

Different from conventional electroactive polymers, here we firstly present a new facile actuator made from aluminum alloy. The high-frequency electrically induced flapping motion was characterized under varied physical factors. This electroactuation results from alternative processes of charge induction and discharge, which is confirmed by the existence of periodical pulse current in the circuit. The metal actuator is of great stability and can maintain several days if not for any structural fatigue. Easy fabrication, high tunable frequency and durability make it potential for implementation of actuators for sensors, microelectromechanical systems and robotics.

cond-mat.mtrl-sci

A novel dielectric elastomer actuator based on polyvinyl alcohol hydrogel electrodes

We firstly demonstrate physically-prepared compliant PVA hydrogel electrodes as a promising supplement in dielectric elastomer actuators. They are capable of conducting high voltages over 5 kV without electrolysis by an electrical double layer effect. The hydrogel electrodes adhere tightly to the dielectric layer, which ensures its structural stability during actuation. All-polymeric actuators fabricated by these electrodes exhibited excellent consecutive working performance over 2960 cycles. The actuation was influenced by applied voltage, ramp rate, electrode elastic modulus and moisture content. A maximum areal strain over 78% was achieved. Tunable transparency, good biocompatibility, long lifetime, low cost and facile fabrication make PVA hydrogel electrode another promising candidate in the fields of sensors, artificial muscles and optical applications.

cond-mat.mtrl-sci