PackMolds: computational design of packaging molds for thermoforming

Abstract

We present a novel technique for designing molds suitable for desktop thermoforming, specifically for creating packaging such as blister packs. Our molds, PackMolds, feature neither undercuts nor negative draft angles, facilitating their easy release from thermoformed plastic sheets. In this study, we optimize the geometry of PackMolds to comply with user-specified draft angle constraints. Instead of simulating the traditional thermoforming process, which necessitates time discretization and specifying detailed parameters for both material properties and machine configuration to achieve an accurate simulation result, we formulate our problem as a constrained geometric optimization problem and solve it using a gradient-based solver. Additionally, in contrast to industrial thermoforming, which benefits from advanced tools, desktop thermoforming lacks such sophisticated resources. Therefore, we introduce a suite of assistive tools to enhance the success of desktop thermoforming. Furthermore, we demonstrate its wide applicability by showcasing its use in not only designing blister packs but also in creating double-sided blister packs and model stands.