Programming Control of a Versatile Ferrofluid: The Exploration of Multifunctional Liquid Robotics

The macroscopic and microscopic responsiveness of ferrofluid to external magnetic fields endow it considerable intelligence and rich functionality, which inspires liquid robotics that can realize arbitrary deformation and perform various functions. Here a versatile ferrofluid is developed, its intelligent manipulation, extensive applications and motion sensing are explored. The ferrofluid is made up of sterically stabilized ultra-small magnetic nanoparticles prepared by a facile one-pot method and purified under a temporary induced aggregation state, showing strong stability, flexible mobility, substantial magnetization, and adjustable concentration. Furthermore, the locomotion and morphology of ferrofluid can be manipulated by a programing control platform that integrates display, drive, control, and cooling modules. This device generates sequential predesigned magnetic fields through the programmable activation of specific electromagnets. Moreover, the intelligent multi-dimensional actuation of substances with a wide range of densities could be accomplished by this ferrofluid in cooperation with permanent magnets manipulated by a robotic arm. This ferrofluid is also developed into a vibration sensor through aligning the magnetic moments in ferrofluids and detecting the flux change in vibration. In addition, the flow, concentration, and speed of ferrofluids can be detected by coupled coils. Such fabrication, control, operation and sensing explorations are central for the development of liquid robotics.