A Substructure Perturbation Method for Systematic Design of Mechanical Metamaterials with Programmed Functionalities

TL;DR

This paper introduces the Substructure Perturbation Method (SSPM), a systematic and efficient computational approach for designing mechanical metamaterials with programmed deformation modes, validated through experiments and outperforming existing methods.

Contribution

The paper presents the SSPM, a novel theoretical and computational framework that accelerates the design process of mechanical metamaterials with complex functionalities.

Findings

SSPM is two orders of magnitude faster than existing methods.

Multiple substructures must be analyzed simultaneously for successful design.

Experimental prototypes demonstrate programmed deformation capabilities.

Abstract

Mechanical metamaterials utilize geometry to achieve exceptional mechanical properties, including those not typically possible for traditional materials. To achieve these properties, it is necessary to identify the proper structures and geometries, which is often a non-trivial and computationally expensive process. Here, we propose a Substructure Perturbation Method (SSPM) for systematic design and search of these materials with programmed deformation modes. We present the theoretical fundamentals and computational algorithms of the SSPM, along with four design problems to investigate the effect and performance of the SSPM. Results reveal the necessity of analyzing multiple substructures simultaneously in obtaining successful designs, and its effectiveness in speeding up numerical processes. In one design case, SSPM is shown to be effectively two orders of magnitude faster than another state-of-art approach while using less computational resources. We also show an experimental validation where the fabricated prototypes can grasp objects respectively by undergoing programmed deformations under corresponding inputs. The proposed SSPM provides new fundamentals and strategies for the design of mechanical metamaterials with advanced functionalities.