  Geometry-morphing Micro Aerial Vehicles (MAVs) are gaining more and more
attention lately, since their ability to modify their geometric morphology
in-flight increases their versatility, while expanding their application range.
In this novel research field, most of the works focus on the platform design
and on the low-level control part for maintaining stability after the
deformation. Nevertheless, another aspect of geometry morphing MAVs is the
association of the deformation with respect to the shape and structure of the
environment. In this article, we propose a novel Nonlinear Model Predictive
Control (NMPC) structure that modifies the morphology of a quadrotor based on
the environmental entrances geometrical shape. The proposed method considers
restricted entrances as a constraint in the NMPC and modifies the arm
configuration of the MAV to provide a collision free path from the initial
position to the desired goal, while passing through the entrance. To the
authors' best knowledge, this work is the first to connect the in-flight
morphology with the characteristics of environmental shapes. Multiple
simulation results depict the performance and efficiency of the proposed scheme
in scenarios where the quadrotor is commanded to pass through restricted areas.
