High-stability electrohydrodynamic inkjet printing based on double closed-loop fuzzy control

Electrohydrodynamic (EHD) printing is a promising micro-nano manufacturing technology. However, the EHD printing process is susceptible to interferences like charge repulsion, electric field, airflow, and platform motion, leading to unstable jetting and nonuniform deposition morphology. In this paper, a double close-loop fuzzy control method based on jet image recognition and micro-current measurement was designed to monitor and control the EHD printing process. A closed-loop control based on the fuzzy control algorithm has been designed to monitor the EHD printing system by taking the feedback information from micro-current and jet image. The experimental results show that the closed-loop control significantly improved the uniformity and stability of the fiber deposition. The volatility percentage of the current decreased from 34% to 12%, the fluctuation range of the fiber diameter was reduced from 35 μm to 15 μm, and the volatility percentage of the fiber spacing decreased from 29% to 9.5%. Additionally, the closed-loop control accelerated the response speed of jet mode conversion. Ineffective deposition of printing jet on the collection plate was shortened from 5 s to 2.2 s. This feedback control optimises the printing quality of micro-nano structures, promoting the advancement of high-resolution additive manufacturing applications.