Optimizing dispensing performance of needle-type piezoelectric jet dispensers: a novel drive waveform approach

The dispensing performance of needle-type piezoelectric jet dispenser constitutes a crucial factor that ensures the quality of additive manufacturing processes. In this paper, a novel approach is proposed to enhance the dispensing performance of needle-type piezoelectric jetting dispensers by introducing a more adaptable driving waveform based on Bézier curves. Initially, the approach considers the electromechanical coupling effect of the needle-type piezoelectric dispenser and constructs a high-precision fluid–solid coupling model of the dispensing process. Subsequently, a multi-physics field joint simulation platform combining Matlab and Fluent is established to systematically analyze control strategies in real service conditions. Next, a new driving waveform based on Bézier curves is introduced, and the control parameters are optimized using a genetic algorithm to address issues such as air bubbles in the droplets and instability of the dispensing process. The optimized waveform based on the Bézier curve reduces the volume of air suction during the dispensing process by over 20% compared to the traditional waveform and eliminates the uncontrolled vibration state of the needle in the fluid, ensuring the stability of the entire fluid refill process. Finally, the optimized control strategy is verified through experiments and compared with traditional methods. The experiment demonstrates its advantages in addressing issues with no air bubbles in the droplets and consistency of the droplets. This study provides valuable insights into optimizing the dispensing performance of needle-type piezoelectric jetting dispensers regarding control strategy.