Research

This research investigates direct printing of conducting polymers on fabrics to enable smart bandage manufacturing. The process allows conductive patterns and functional electronic features to be formed directly on textile substrates, supporting flexible and wearable device fabrication. Such a manufacturing approach provides a pathway toward biomedical textiles with integrated sensing and electronic functionality.

Traditional photopolymerization processes offer precise geometric control but provide limited capability in tailoring internal particle distributions. To overcome this constraint, we develop an acoustic assembly photopolymerization approach that integrates acoustic radiation forces with curing kinetics to direct particle organization in situ. This method enables programmable formation of anisotropic line-patterned composite structures with well-defined spatial distributions. Coupled with theoretical modeling of particle dynamics and curing behavior, this process establishes a framework for designing functional materials with controlled microstructures, supporting applications such as autonomous droplet transport and surface-driven fluid manipulation.

This research focuses on direct ink writing on a rotating mandrel for the fabrication of hollow tubular structures with microscale features. By combining material extrusion with mandrel rotation, the process enables patterned deposition on cylindrical surfaces and supports the manufacturing of straight, curved, and more complex tubular geometries such as stent-like structures. This approach expands the capability of direct ink writing beyond planar substrates and provides a manufacturing route for customized cylindrical wrappers and other micro-scale tubular devices.

This research focuses on the direct printing of conductive hydrogels using two-photon polymerization. By developing a PEDOT:PSS-based hydrogel formulation compatible with the TPP process, the work enables the fabrication of high-resolution conductive microstructures with improved swelling behavior, electrical performance, and biocompatibility. This approach extends two-photon polymerization beyond conventional structural materials and provides a pathway for manufacturing micro-scale bioelectronic devices, soft conductive architectures, and other functional hydrogel-based systems.

Few of AM technologies are able to fabricate multiple materials and composites, yet they are limited to one class of materials (polymer or metal).   To close the  gap of multi-classes material additive manufacturing with controlled dispersion patterns, we are examining novel field-assisted additive manufacturing processes, with the goal of printing multi-classes materials with controlled dispersion patterns.  Such multi-material AM technology could be used to fabricate smart materials/structures directly from digital models.

In a typical Additive Manufacturing system, it is critical to make a trade-off between the resolution and build area for applications in which varied dimensional sizes, feature sizes, and accuracy are desired. We are investigating novel AM systems with dynamic resolution control and build size control, with the goal of bridging micro- or even nano-AM to meso- or even macro-AM without sacrificing the build speed.

Through introducing external fields and precise temperature control, we are able to innovate the Direct Ink Writing (DIW) process to unlock speed restriction while significantly expanding versatility and substrate choices. Compared to the state-of-the-art DIW processes, our new direct ink writing technology shows orders of magnitude faster direct writing speed (>0.5 m/s), capability of printing on super rough surfaces which were impossible before, capability of printing within confinements, and higher interface strength in multi-material printing.

Additive Manufacturing of Energy Components

We are improving various existing Additive Manufacturing technologies or developing novel manufacturing methods,  including direct ink writing, selective laser sintering, and stereolithography, for innovative applications in thermal energy storage, next generation batteries, super capacitors, and flexible electronics.

Additive Manufacturing of Biomedical Components

Each year, more than 100 million animals are killed in U.S. for experimentation purpose. Despite its ethical issue and super high expense, the drug dispersion mechanisms learned from animals rarely translated to humans. We are exploring direct digital manufacturing of anatomically accurate, physiological functional physical models for in vitro experiments and bio-compatible soft robots for future biomedical applications.

How to make 3D Printing a real RAPID manufacturing technology? In current AM systems, processing speed and part quality are critical challenges for producing parts with relatively wide solid cross sections. We are exploring continuous projection Stereolithography process (DLP 3D Printing) through liquid-gel-solid multi-phase modeling, highly oxygen window design, gradient light delivery planning, to reduce separation force and liquid filling time significantly, which will finally result in ultra-rapid manufacturing of products with any SOLID geometries and sizes.

Previous Projects: 

-Manufacturing Capability:

• Smooth Surface Fabrication in Mask Projection based Stereolithography

• Multitool and Multi-Axis Computer Numerically Controlled Accummulation for Fabricating Conformal Features on Curved Surfaces

• An Integrated CNC Accumulation System for Automatic Building-Around-Inserts

-Cost Effective:

• A Low-cost Parallel Kinematic Machine for Multidirectional Additive Manufacturing

-Time Efficient:

• A Fast Mask Projection Stereolithography Process for Fabricating Digital Models in Minutes

• Fast Micro-Stereolithography Process based on Bottom-up Projection for Complex Geometry