Advanced scanning infrared laser system for dynamic measurements on soft materials

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Mechanical vibrations excited by fluid flow, of which the applicant is a renowned expert, affect the safe operation of systems of crucial importance to the public; they may result in the release of fissile material in the cores of nuclear plants as well as in the collapse of large human arteries such as the aorta and in the failure of relevant aortic grafts. Today it is not sufficient to avoid resonances according to traditional methods, but it is necessary to predict the severity of the vibrations reached during catastrophic events. Vibration testing requires the accurate measurement of prototypes by advanced non-contact systems like scanning laser Doppler vibrometers (SLDVs). These turnkey systems can measure the vibration mode shape of entire surfaces in terms of very accurate velocity and displacement of thousands of points. Decades of experience with SLDVs indicate that no other technology measures with nanometer accuracy slow displacements as well as millions of oscillations per seconds on thousands of points on surfaces in different conditions (e.g. immersed in water). The main experimental asset of the applicant is now one SLDV, the only one at McGill University, that, after allowing disparate researches, reached its end of life. Single point models are available, but for an important fraction of the price they measure one point only, thus they are hundreds of times less time effective. The requested equipment is a SLDV that substitutes and improves the current model. Differently than the old one available, it will employ a novel infrared laser technology, allowing the measurement of non-reflective surfaces such as rubbers and biomedical materials. While it will replicate and improve previous performances on metallic materials, it will also be a key factor in allowing for the first time the ex vivo dynamic characterization of large human arteries (e.g. aortas). The equipment is compact and flexible and, thanks to a video-camera, can be aimed intuitively onto structures giving as output intuitive animations, also used for training purposes. It is complete with PC-based capabilities, easy to use and extremely fast. Thus, it is easily and continuously available to any researcher needing it. It is rugged and can be transported to other locations without delay. It is safe, so it can be shared immediately and with little training between four graduate and two post-graduate students already supervised by the applicant. SLDV is by far the leading technology in vibration testing, so hands-on experience is absolutely necessary for any HQP pursuing employment in this field. The proposed SLDV will visualize on screen the direct impact of vibrations on systems at the base of modern life; they will improve the safety of the Canadian public and give data necessary to develop a new generation of cardiovascular prostheses and nuclear reactor cores. Consequently, the academic success and employability of HQP in these sectors will be highly facilitated.