Model-based robust design for time-pressure fluid dispensing using surrogate modeling

In industry, the time-pressure dispensing system has been widely used to squeeze the adhesive fluid in a syringe onto boards or substrates with the pressurized air. For consistent dispensing of the fluid volume, it is vital to have a robust dispensing system insensitive to operation condition variation. In academia, much dispensing research has been done via modeling and control approach. However, a systematic design approach to determine an optimal operation condition for time-pressure dispensing is not available. This paper presents such a method for both line dispensing and dot dispensing, by means of model-based robust design. In particular, all kinds of the quantities involved in the dispensing task is classified into three groups: the design variables (DV), the design environment parameters (DEP) and performance functions, in the framework of model-based robust design. By this approach, the sensitivity analysis can be developed. While the sensitivity for DEP is analytic, whereas the sensitivity function for DV is more complex and have to be approximated by surrogate modeling. Thus the robust design can be used for time-pressure dispensing. The results show that dispensing performance robustness can be improved by choosing the appropriate system parameters. Simulations performed thereafter validate the effectiveness of this design method.