Final Project Reprot: Electrospinners

This report provides a comprehensive overview of the development of the Electrospinning Machine Year 2 project. In the year 1 iteration of the project, the previous team successfully produced nanofibers, but in an unaligned, random orientation due to the usage of a flat plate collector. Building upon the foundation laid by the previous team, this year's effort focuses on enhancing the functionality of the existing electrospinning machine by improving the alignment of nanofibers and enabling the simultaneous projection of multiple polymer solutions. Key objectives include the design of a cylindrical collector subsystem, the development of a high-precision motor system, the integration of a dual-barrel syringe for modular solution ejection, and the establishment of metrics for evaluating fiber alignment. At the core of the design is an in-house manufactured cylindrical collector made of aluminum, chosen for its conductivity, durability, and cost-effectiveness. Driven by a high-speed servo motor capable of reaching speeds between 2000-6000 rpm, this subsystem is designed to optimize nanofiber alignment while adhering to OSHA mechanical and electrical safety standards. The motor system includes a DC power supply, a PWM motor controller with adjustable speed settings, and a modular stand mechanism designed for future scalability and improved alignment precision. The syringe pump subsystem features a dual-barrel syringe mechanism, allowing for the simultaneous ejection of multiple polymer solutions at controlled flow rates. This modular solution avoids significant modifications to the existing syringe pump system, reducing cost and complexity while meeting the objective of projecting multiple solutions. Needle tips and flow rates are optimized to achieve fiber diameters of approximately 200 nm, enhancing the system's adaptability to various electrospinning applications. Fiber alignment is quantified using MATLAB and ImageJ to evaluate and compare nanofiber orientation against the fiber alignment of the previous team’s sample. The goal is to achieve more aligned nanofibers by producing samples with a lower interquartile range for the angle distribution. A lower interquartile range (IQR) will show that the fibers are oriented within a smaller range of angles whereas a larger IQR will show that fibers are oriented across a wide range of angles. The color maps and histograms provided by ImageJ and the IQR provided by MATLAB will provide an analysis of the fiber alignment. Additionally, ImageJ will provide a measurement of the fiber diameters to ensure that fibers are produced with diameters of 200 nm ±20%. Testing confirmed that the completed prototype met all project objectives and working criteria. The system is capable of producing aligned nanofibers with diameters of 200 nm ±20%, which has been successfully proven using image processing to quantify fiber alignment.