LCE-LM Composites for Soft-Matter Embodied Intelligence

Major Goals: The goal of this project is to introduce a class of soft elastomer composites that demonstrate embodied intelligence by sensing, processing signals, and dynamically responding to external conditions in an autonomous manner. In contrast to current methods that utilize distributed motors and electronics, this work is focused on achieving autonomy through intrinsic material functionality. Rather than rely on microelectronic or mechatronic hardware, the material system that we are developing achieves sensing, signal processing, and actuation through internal electro-thermo-mechanical coupling of the constituent material phases. To achieve embodied intelligence, we are developing soft material architectures composed of liquid crystal elastomers (LCEs) and liquid metal (LM) alloy. One embodiment of this is a percolating network of microscale LM droplets suspended within an LCE matrix. These LCE-LM composites exhibit a unique combination of electrical, thermal, and dynamic properties that have never before been demonstrated in other soft material systems. We are also exploring a second embodiment in which strips of LCE are coated with a thin film of biphasic LM-silver electrodes. Heating causes the LCE-LM-Ag strips to form helical coils that entangle and create semisolid networks. For both of these material systems, reversible shape change and actuation is achieved through the application of either thermal or electrical stimulation. Moreover, the materials are capable of sensing deformation or damage through changes in electrical resistivity of embedded conductive pathways. In this way, active response is accomplished through electro-thermo-mechanical coupling that arises from the interplay of thermally-induced LCE phase change, flow of electrical current, and changes to the shape or structural connectivity of the material.