Discovering Optimal Flexible Circuits Using Graph-Based L-System Network Optimization

Abstract

A multiphysics topology optimization tool, if created properly, has the ability to be used to evaluate and analyze AC circuit designs for the development of novel electronics and flexible circuits created from liquid metal-based inks. The benefits of combining an optimization tool with the utilization of liquid metal-based inks include minimal degradation in electrical performance, a large amount of deformation tolerance, faster identification of ideal design solutions based on input parameters, and increase in flexibility. The following work focuses on the development of a tool to greatly expedite a resistor-inductor-capacitor (RLC) circuit optimization towards the creation of electro-mechanical systems such as flexible circuits. Given specific target design specifications, the optimizer was able to meet requirements on all design problems with a 92 – 98% accuracy in a run time of 2 hours. In comparison to other pre-existing methods, this is a much more efficient and faster approach. The topology optimization approach was applied towards the determination of optimized circuit networks. In-spired by the successes of this design approach, the fabrication and testing of liquid metal-based flexible circuits were explored. Fabricated liquid metal-based components proved to have an error to the designed performance of ±5 – 10% which is similar those currently on the market. Three liquid metal-based interdigital capacitor (IDC) designs were created, fabricated and mechanically deformed in two different directions. A combination of an optimization approach with fabrication procedures for developing electronic components has the potential of creating the next generation of flexible circuits that are simple to produce and cost-effective.