Design of Inertial Morphing Prototype Using Fusion360 API for Attitude Dynamics

Garriott’s–Dzhanibekov’s effect is the periodic flipping of the body when spun about its intermediate principal moment of inertia axis, but the body does not perform the flipping motion when spun about its other two axes. A novel prototype concept simulating an unmanned spacecraft is designed and developed using Autodesk’s Fusion360 that can change its inertial properties to control its attitude dynamics by moving masses in a scissors like mechanism. The procedure of changing inertial properties is called Inertial Morphing (IM). The concept of IM is well developed in the theoretical and simulation domains, but no dedicated papers in the hardware domain. Autodesk’s Fusion360® is a capable cloud-based 3D modelling software. For efficiency during the design process, several calculations need to be conducted using equations that are not available in the CAD environment, but these equations require the mechanical properties of the CAD model and is an iterative process. Using the Application Programming Interface (API) provided by Autodesk, a Python program is used to control the CAD model and analyze the inertial properties of the prototype by performing calculations within the CAD software environment using external Python libraries. This paper presents the working principle of the prototype that performs IM to control its attitude and shows how Fusion360 API can be used to increase the efficiency of developing an IM prototype by performing calculations within the CAD software environment by automating the transition from maximum to intermediate moments of inertia for the activation of IM even with complex assemblies. Visualizing the effects of the selected mechanism in terms of plots and analyzing the effects of different parameters on the period of the flipping motion without exporting data to any external applications.