In nature, several species of parasitoid wasps have a thin and flexible needle-like structure, called ovipositor, which is used to deposit eggs in a host (e.g., a larva) hidden into tree trunks or fruits. The wasp ovipositor consists of three segments, called valves, longitudinally connected that can slide along each other.  The animals can drill in different substrates by actuating the valves in a reciprocal motion and steer by changing the relative positions of the valves during probing (i.e. protracting and retracting of the valves).

We are currently developing a novel steerable needle for minimally invasive interventions inspired by the wasp-ovipositor. However, the steering mechanisms used by the animal is not yet fully understood.

The project will focus on understanding how the steering mechanism works and which characteristics of the ovipositor play a relevant role.

The student will use detailed 3D images of different ovipositors to design several replicas of the wasp ovipositor in larger scale with 3D printed techniques. The prototypes will be tested with an experimental facility where motion pattern and speed can be controlled. The ovipositors will be inserted in gelatine of different concentration to study the design parameters effecting the steering mechanism.

Contact: Marta Scali, m.scali@tudelft.nl

Picture adapted from “Braconid Wasp Ovipositing” by Katja Schulz is licensed under CC BY 2.0.