RESEARCH

Insects and reptiles, with an evolutionary history of millions of years, exhibit fantastic adaptations to their environment. They can walk on land and underwater, jump, dive, swim and fly. They also have surprisingly intricate capabilities, like the ability to overcome lack of water by collecting water from humid air and transporting it efficiently to different parts of their body. Such capabilities have evolved through the development of unique materials and mechanisms. Biomimicry follows nature’s guidelines in order to synthetically recreate such systems for future designs and products. Its ultimate ambition, however, is to go beyond what can be found in nature and to design faster and more efficient mechanisms. Inspired by beetles, spiders, lizards and other animals, our lab develops innovative routes for the propulsion of small objects, and the actuation and dynamic transport of liquids on the nano-to-micro scales.

Special focus:

Biphilic responsive surfaces, 2D networks for liquid collection and transport, Insect bioinspired robotics, 3D printing of bioinspired structures, Underwater adhesion, Mechanics of soft matter

Research projects:

Bioinspired 2D and 3D Networks for Collecting and Directing Liquids

This line of research is currently the core project in my group. In this project, we design and produce unique surfaces made to collect and transport liquid spontaneously in a controlled direction. We also quantify water collection on them from fog and dew and establish chemical and geometrical guidelines to tailor the performance of such engineered surfaces to specific applications. The surfaces are inspired by the wetting properties and structural designs found in insects and plants. We currently focus on liquid diodes. Namely, sub-millimeter surface structures that promote liquid transport in one direction but prevent flow in the other direction. We 3D-print open-channels liquid diodes in high resolution, with highly modifiable design and pioneer the construction of large scale networks with hundreds and thousands diodic units. Ideally, we would like to elucidate transport phenomena in such networks in 2D and 3D.

Liquid Directional Transport-Biphilic surfaces.jpg

Insect Inspired 3D Printed Flexible Wings for Miniature Flapping Drones

In this project, we combine the basic understanding of insect flight mechanics and advanced additive manufacturing, using a biomimetic approach, in order to develop insect bioinspired flexible wings for miniature flapping Unmanned Aerial Vehicles (UAV). In my lab, we manufacture of the wings using high resolution 3D printing, that allows for structural variation of the wing and a variety of printing materials. Based on the natural design of beetles’ wings, we modify its structure in order to engineer flexural deformations that suit specific flight types, including: hovering, fast flight, flight with high payload (high wing loading), and increased time in air (high energetic efficiency). In this way, it is possible to adjust the wing to the specific operations of the miniature flapping drones. The ability to engineer flexural deformations in order to tune aerodynamic forces by intelligent design of bioinspired wings comprises a groundbreaking novel approach in the field.

In my lab, we design, fabricate and test the mechanical response of the insect-inspired 3D printed wings. We also construct testing apparatuses in order to quantify the aerodynamic performance of the 3D printed wings.

The Biomechanics of Female Locust Oviposition System

In this project, we study several aspects of the female locust oviposition system. It is a fantastic example of joint efforts between biologists and engineers in order to elucidate multiple biological questions related to biomechanics and develop bioinspired robots.
The female locust has a unique digging mechanism for digging and propagating underground in order to lay her eggs in a protected environment. The female extends her abdomen, while using two pairs of digging valves to shovel the granular matter and create a stable tunnel underground.
The first aspect of the multi-facets project focused on the biomechanics of the female locust digging valves and their ability to improve their stiffness 16 folds within a period of roughly two weeks from molting until the moment of oviposition.
The second part of the project dealt with the female locust nerve cord and its ability to extend up to approximately 300 % of its original length. This hyperextension of nervous systems is rarely observed in nature and could be potentially used for developing synthetic skin and engineered tissues. We measured the dynamic mechanical response of this very delicate (sub-millimeter scale) tissue to tensile stretching, in physiological conditions (liquid, temperature), using a high resolution force transducer in a dynamic mechanical analysis setup.

Currently, we study the materials properties and mechanism of the locust digging valves used for oviposition. The valves are biological composite materials and constitute structural and materials gradients. We aim at elucidating the relation between the nano and micro-structures and the mechanical properties. We realize more and more that the materials the valves are made of are meant to improve resistance against wear rather that bulk failure. In addition, we develop a female-locust inspired robotic digger that will have the structure and kinetics of the female locust. This enables us to explore different digging modes using machine learning and, in addition, will be used a robot-assisted platform to understand biological questions dealing with efficiency of this digging mechanism and establishing guidelines for the development of bioinspired 3D printed diggers, tailored for different environments.

Social Interactions in Groups of Robotic Swimmers

In this project, we use robotic swimmers that we designed, developed and fabricated in my group in the last two years (Advanced Intelligent Systems, 2022) in order to implement and examine mutual interactions between robotic swimmers underwater. To this end, we aim at implementing minimal sensing capabilities that will allow swimmers to sense approaching neighbors. As a result, swimmers will have the ability to gather in groups or scatter and avoid each other, similarly to interactions between swimmers in nature. While we aim at larger groups of swimmers, we currently focus on interactions between pairs of swimmers. In parallel, we use statistical mechanics in order to understand and simulate interactions between many members within groups of swimmers.