Multilayer Microhydraulic Technology

Technology

A microhydraulic actuator works via electrowetting, a technique that applies electrical voltage to water droplets on a solid surface, thereby distorting the surface tension of the liquid. This distortion is leveraged by the actuator when it forces the liquid droplets inside the actuator to move the entire unit. Originally, this took place via a thin polyimide film sitting on top of a thick base. This technology provides enhancements by incorporating the electrode and droplet arrays into one thin film. Multiples of this singular, thin layer can be stacked while remaining individually powered to form a liquid interconnected network. In doing so, this technology allows for optimized characteristics of microhydraulic systems (increased power, torque, etc.).  

Problem Addressed

The ubiquitous inductive electric motor has been impossible to miniaturize below approximately a gram in mass, due to inherent inefficiencies from thermal losses.  Achieving motion in a small form factor has remained a technological challenge, often addressed with piezoelectric or thermal actuators working at sub-optimal efficiencies.  Microhydraulic actuator technology provides an efficient and scalable motor technology solution, for motors down to milligrams in mass, and provides much higher torque density for motors at any size scale. 

Advantages

• Optimized characteristics of traditional microhydraulic systems  
• Increased reaction time of system due to its multilayer design  
• Decreased stiction and abrasion common in other mechanical systems

Publications

Jakub Kedzierski and Hero Chea. Multilayer microhydraulic actuators with speed and force configurations. Nature. 2021 Mar 11. doi: 10.1038/s41378-021-00240-7