Design for manufacturing and assembly of a multi material bioprinting system towards tissue engineering applications

Abstract

Light-based techniques have great potential in bioprinting for tissue engineering, given their inherent advantages in high spatial resolution (10–100 μm) and improved cell viability (>85%) compared to traditional extrusion-based systems. However, current apparatuses found in the state of the art are limited in usability and functionality due to legacy single-material design constraints and the early development stage of photopolymerization-based bioprinters. As tissue constructs become increasingly complex, there is a need to establish a new framework for light-based equipment tailored to specific tissue engineering applications. This work presents the development of multi-material bioprinting equipment that integrates 4K digital light projection with an automated rotating four-vat system, enabling sequential use of bioinks with distinct mechanical and biochemical properties. For this endeavor, the scalability and manufacturability of the apparatus were addressed using Function Tree analysis, Quality Function Deployment (QFD), and Design for Manufacturing and Assembly (DFM&A) principles. These tools guided the definition of a feature set for meniscal tissue regeneration, including layered constructs with stiffness gradients and bioactive cues. The system was designed in Fusion and fabricated using a combination of rapid prototyping techniques. This included the 3D printing of custom resin vats, CNC machining of structural elements, and the development of bespoke electronic components for control and actuation. Initial validation was carried out using a single-vat configuration and Anycubic clear photopolymer resin. Printing trials demonstrated the resolution capacity of the optical system and successful layer-by-layer polymerization using 405 nm light exposure. These results confirm the operational feasibility of the system and establish a baseline for future multi-material implementation using photocurable bioinks