Dynamics and mechanics of shape morphing structures

Context. In Nature, living materials are constantly evolving and adapting their shape to the environment, a feat that is lacking in engineered materials. To achieve this, differential growth within the tissues is key, as it induces mechanical stresses and thus the buckling in a rich variety of shapes. Over the last decade, emerging approaches have embraced this paradigm to develop bioinspired synthetic responsive materials (to external stimuli, such as, temperature, magnetic field, pressure) with in-plane distortions, and hence shape-morphing capabilities. However, despite rapid developments, current efforts primarily focus on programming the final equilibrium shape, overlooking both the dynamical trajectory of the transformation and the mechanics of the morphed structure. As a result, exciting biomedical applications perspective in minimally invasive surgery, rehabilitation and soft robotics remain so far beyond reach.

Objectives. During this postdoc, you will develop 3D-printed soft architected structures containing a network of interconnected cavities. The first objective will be to design structures in which both the local metrics and the extrinsic curvature can be fully programmed and rationalized using nonlinear homogenization techniques. This will allow us to solve the inverse problem and program complex 3D shapes, but also to study the mechanics of these frustrated structures.

A second objective will be to control the flow and the pressure distribution within the soft architected structure, when actuated mechanically or when inflated. The aim will be to characterize and rationalize the fluid structure interaction at play to program the shape changes in space and time.

The postdoc will take place at the Interdisciplinary Physics Laboratory (LIPhy), in Grenoble, in the Move team. The lab is surrounded by three mountain ranges (Chartreuse, Belledonne, Vercors) and offers a unique environment.

 

Position information:
Duration: 2 years
Starting date: flexible, starting from 01/01/2025
Location: LIPhy, 140 rue de la Physique, 38400 Saint Martin d’Hères
Feel free to contact Emmanuel Siéfert to discuss the project.