Crashworthiness

Research focus

The Peer review has evaluated this group as Good

The research activity within the area of crashworthiness is characterized by a close integration between experimental and numerical approaches. DIA makes use of a number of different experimental facilities as well as some of the most advanced explicit finite element codes, for crash analysis, and multi-body programs, for non-linear transient dynamics. Experimental tests and numerical simulations are used to investigate the response of structural components of helicopters, fixed wing aircraft and road vehicles in different impact conditions, to design new crashworthy structures with respect to events such as birdstrike, hail impact, and water landing in emergency, and to study fuel tank crashworthiness and road safety devices. The finite element numerical codes mainly used by the research team are at present LS-Dyna, ESI/PamCrash and HKS/Abaqus Explicit. The in-house developed multi-body explicit code VEDYAC, now available in the enhanced MUSIAC version, represents a powerful tool to analyse the overall crash response of large structures with compact models, allowing one to perform reliable simulations of long lasting crash scenarios in a short computing time. Thanks to these characteristics, MUSIAC is extensively used for the design and optimisation of crashworthy structures. The study team focuses on different topics, as detailed below: Development of anthropomorphic test dummy models in finite element, multi-body and hybrid approaches, extensively validated against experimental data; these models are a powerful tool used for both automotive and aircraft crashworthiness studies, in several internal projects, in co-operation with industry and for EU-funded projects; Numerical analysis of bird strike on fixed wing and tilt rotor aircraft: considerable experience has been acquired with finite element analysis, using different approaches as total Lagrangian, ALE and SPH models; such analyses and the related models are now reliable validate design tools, to be used for predicting the bird-strike performances of crucial structural parts, as leading edges and wind sceens; Numerical analysis and experimental testing on helicopter crashworthiness with particular attention to subfloors and fuel tanks: one of the most significant results of the research on fluid structure interactions is a new concept for crashworthy fuel tanks, which has been patented and is currently under development; Numerical analysis and experimental testing of aircraft landing gear in hard and crash landing conditions, with development of crash stages; a device for triggering the stage has been patented; validated design tools and procedures have been produced and are currently in use; Development of constitutive laws for the material characterization and the interlaminar stress modelling in composite layers; Numerical analysis and experimental testing of ditching, based on simplified models; Numerical analysis and experimental testing of road vehicle dynamics and crash: a significant activity is dedicated to the road restrain systems (safety barriers) both in terms of research and in terms of the development of a European normative for these devices. The approach used by the research team is based on a strong integration of numerical and experimental methods, with contacts and co-operation with the main European and American Research Institutions; the European Project ROBUST (Road Barrier Upgrade of Standards), was leaded and completed with very valuable scientific results; Design, numerical analysis and experimental testing on composite absorbers for racing car installations; Design, numerical analysis and experimental testing on crashworthy helicopter subfloors structures. Design and optimisation procedures have been developed and validated for energy absorbing sub-floor helicopter structures, both in the shape of riveted aluminium structures and of co-cured composite structures. A necessary parallel experimental capability has been developed and used to validate the new design procedures. Optimisation of crashworthy seats for fixed and rotary wing applications: taking advantage from the good experimental facilities and the analytical experience available, advanced optimisation procedure have been developed and validated for aircraft and helicopter seats, designed to fulfil the crashworthiness requirements of the current regulations. The DIA crash lab has obtained the following accreditations: Research topic 4.3 - Crashworthiness 2-56 o TUV 97/24/EC Chapter 11 amended 2005/51/EC. o SQP UNI CEI EN ISO/IEC 17025:2000 Racing car seats crash tests FIA 8855-1999. o SQP SIT for speed measurement calibration (0-100 km/h) UNI CEI EN ISO/IEC 17025:2000 o SIT for accelerometer measurement UNI CEI EN ISO/IEC 17025:2000

Dipartimento di afferenza

Dipartimento di Ingegneria Aerospaziale

Docenti afferenti

Vittorio Giavotto (Full Professor)
Marco Anghileri (Associate Professor)
Chiara Bisagni (Associate Professor)
Paolo Astori (Assistant Professor)
Gerardus Janszen (Assistant Professor)