A space mission involves a wide range of structural systems, spanning from heavy-load-bearing engine supports integrated into launch vehicle structures to lightweight sandwich panels used in solar sails, as well as protective enclosures for onboard electronics, batteries, and instrumentation. The primary function of these structures is to ensure mission success by safeguarding subsystems against mechanical and environmental loads encountered during ground handling, launch, orbital operations, and deployment. Structural integrity must be maintained without failure, instability, or excessive deformation that could impair the performance of critical components such as antennas and sensors. Within this framework, the course Spacecraft Structures aims to provide students with analytical methodologies and computational mechanics tools commonly employed in the aerospace sector. A substantial portion of the course is dedicated to the development and application of mathematical models for the analysis and characterization of space structures subjected to both mechanical and field-induced loads, under static and dynamic conditions. Particular emphasis is placed on nonlinear structural behavior, with specific attention to deployable and inflatable structures. The course also introduces fundamental concepts and computational techniques for multibody dynamic analysis of space mechanisms and spacecraft systems.

At the end of the course, students will be able to: * Demonstrate knowledge and understanding of the classification of space structures, the materials used in their construction, and the loads arising from the space environment; * Demonstrate knowledge and understanding of mathematical models for the analysis of structures subjected to mechanical and multiphysics loads, under static and dynamic conditions, within both linear and nonlinear regimes; * Demonstrate knowledge and understanding of computational tools and methods for the structural verification of spacecraft; * Apply the acquired knowledge to address and solve design problems related to space structures and their components.

Basics of structural analysis.

Module I (20 hours) – Introduction to the design of space structures and mechanisms. Overview of the space environment and typical loads encountered during launch and in orbit (e.g., thermal loads, acoustic loads, decompression loads, etc.). Fundamentals of dynamics. Natural frequencies and mode shapes. Modal superposition methods. Effective modal masses. Static condensation method (Guyan). Craig–Bampton method and dynamic substructuring. Response to random vibrations and acoustic loading. Module II (25 hours) – Introduction to continuous systems and the finite element method for static and dynamic analysis. Formulation of 1D/2D finite elements, with emphasis on plates and shells; applications to laminated structures. Elastic response to thermal loads. Nonlinear problems in space structures, including material, geometric, and boundary nonlinearities. Green–Lagrange strain tensor and geometrically nonlinear finite element formulation. Overview of numerical solution techniques, including Newton–Raphson and path-following methods. Deployable space structures (e.g., tape springs, TRAC booms, etc.). Module III (15 hours) – Rigid body mechanics. Kinematic equations and rigid body dynamics. Flexible bodies in multibody analysis of space mechanisms. Deployment mechanisms. Inflatable structures for manned and unmanned applications.

For further in-depth study of related or complementary topics, reference is made to other courses. For example: dynamics and vibrations (Aeroelasticity); FEM analysis and stiffened shell structures (Aeronautical Structures); structural instability and fatigue design (Aerospace Vehicle Design); materials and composite structures (Aeronautical Structures & Additive Manufacturing Design and Fabrication for Aerospace Applications).

The course consists of theoretical lectures (33 hours), classroom exercises (18 hours), and laboratory sessions (9 hours). Classroom exercises are intended to reinforce the topics covered during lectures. These will include numerical problems on the dynamic characteristics of simplified launcher–payload systems, preliminary estimation of launch loads, vibro-acoustic response, and the solution of nonlinear (elastic) problems. Laboratory activities provide hands-on experience with software tools for nonlinear finite element analysis and multibody dynamics. Students are required to prepare individual reports on both classroom and laboratory exercises. These assignments must be submitted during the examination and will contribute to the final grade.

No prerequisites are required beyond the material covered in the lectures. Some topics may be further explored in the following references: E. Carrera, M. Cinefra, A. Pagani, Fundamentals of Elasticity and Structural Theory, AIDAA Educational Series. T. P. Sarafin, Spacecraft Structures and Mechanisms, Space Technology Library. J. J. Wijker, Spacecraft Structures, Springer.

Slides; Dispense; Esercizi; Esercitazioni di laboratorio; Materiale multimediale ; Strumenti di simulazione;

Modalita di esame: Prova orale obbligatoria; Elaborato scritto individuale;

Exam: Compulsory oral exam; Individual essay;

... The assessment consists of an oral examination to evaluate the knowledge acquired during the course and through the exercises. The oral exam is expected to last approximately 30–45 minutes and will include 3–4 questions. At least one of these questions will address the content and evaluation of the individual written report, whose contribution to the final grade will carry the same weight as the other questions. Grades will be expressed on a 30-point scale, and the exam will be considered passed with a minimum score of 18/30. The evaluation criteria are based on the achievement of the following objectives (consistent with the intended learning outcomes stated above): 1. Knowledge of the operational environment and computational tools for the verification of space structures and mechanisms. 2. Ability to use simulation software to perform advanced structural analyses and evaluate the behavior of space structures under various loading conditions. 3. Ability to identify and solve design and analysis problems related to space structures. 4. Ability to apply the knowledge acquired during lectures and exercises to practical engineering problems. 5. Ability to communicate the results of structural analyses clearly and accurately, both in written and oral form, using appropriate technical terminology.

Gli studenti e le studentesse con disabilita o con Disturbi Specifici di Apprendimento (DSA), oltre alla segnalazione tramite procedura informatizzata, sono invitati a comunicare anche direttamente al/la docente titolare dell'insegnamento, con un preavviso non inferiore ad una settimana dall'avvio della sessione d'esame, gli strumenti compensativi concordati con l'Unita Special Needs, al fine di permettere al/la docente la declinazione piu idonea in riferimento alla specifica tipologia di esame.