In the past decade, liquid-crystal network (LCN) technology has been used for the development of soft actuators based on the controlled reversible changes of the order parameter of the oriented polymer network. Various deformations ranging from simply bending or curling to complex origami type of morphing are demonstrated to lift weights, mimic nature in shape and color, or transport materials. Herein, we propose the use of a liquid crystal network for soft robotics where the various molecular accessories are assembled in the two dimensions of a coating. For instance, the LCN surface deforms dynamically into a variety of pre-designed topographic patterns by means of various triggers, such as temperature, light and the input of electric field. These microscopic deformations exhibit macroscopic impact on, for instance, tribology, haptics (Fig. 1a), laminar mixing of fluids in microchannels and directed cell growth. Another robotic-relevant function we brought into the LCN coating is its capability to secret liquids under UV irradiation (Fig. 1b) or by an AC field. This controlled release is associated with many potential applications, including lubrication, controlled adhesion, drugs delivery, agriculture, antifouling in marine and biomedical devices, personal care and cosmetics. With this we bring together a tool box to shape soft robots into two-dimensions, well designed to operate in area where man and machine come together
Figure 1. Images present the impression of (a) dynamic surface topographies towards haptics and (b) on demand secretion of liquids.
Danqing Liu received her bachelor degree in Physics at University of Electronic Science and Technology of China, China. She continued her study and received master degree in Electrical Engineering in 2009 at the Delft University in The Netherlands. She worked on her PhD project at the Department of Mechanical Engineering of the Eindhoven University of Technology, The Netherlands during which she developed polymer responsive surfaces based on hydrogels and liquid crystal polymers. In 2013 she joined the Department of Chemical Engineering and Chemistry at the same university working as postdoctoral student on new mechanisms of surface activation. From 2015 she is Research Fellow at the Institute of Complex Molecular Systems in Eindhoven, The Netherlands. Her current research focus is on developing responsive coatings that change properties such as surface topography, color, polarity and liquid secretion. Dr. Liu has more than 20 publications in important peer reviewed journals as Nature Communications, Proceedings of the National Academy of Science, Angewandte Chemie Int. Ed. and Advanced Materials. She is recipient of a Dutch National 3TU grant, and a Veni grant from Dutch National Science Foundation (NWO) to proceed her research within the Netherlands