INDUSTRIAL engineering, RAPID prototyping, SCAFFOLDING, BIOMECHANICS, STAINLESS steel, and TITANIUM
The development of successful scaffolds for bone tissue engineering requires a concurrent engineering approach that combines different research fields. In order to limit in vivo experiments and reduce trial and error research, a scaffold screening technique has been developed. In this protocol seven structural and three biomechanical properties of potential scaffold materials are quantified and compared to the desired values. The property assessment is done on computer models of the scaffolds, and these models are based on micro-CT images. As a proof of principle, three porous scaffolds were evaluated with this protocol: stainless steel, hydroxyapatite, and titanium. These examples demonstrate that the modelling technique is able to quantify important scaffold properties. Thus, a powerful technique for automated screening of bone tissue engineering scaffolds has been developed that in a later stage may be used to tailor the scaffold properties to specific requirements. [ABSTRACT FROM AUTHOR]
Grujicic, M., Pandurangan, B., Xie, X., Gramopadhye, A.K., Wagner, D., and Ozen, M.
International Journal of Industrial Ergonomics. May2010, Vol. 40 Issue 3, p345-355. 11p.
PRODUCT design, RAPID prototyping, COMPUTER integrated manufacturing systems, ERGONOMICS, FATIGUE, MUSCULOSKELETAL system, MOTOR vehicle driving, and BIOMECHANICS
Abstract: The main causes for long-distance driving fatigue experienced by vehicle drivers are investigated computationally using musculoskeletal modeling and simulation methods. A rigid-body model of a prototypical adjustable car seat is constructed as a part of the present work and combined with a public-domain musculoskeletal model of a seated human. Seated-human/car-seat interactions associated with typical seating postures of the vehicle driver are analyzed using the inverse-dynamics approach while the “minimum-fatigue” criterion is utilized to deal with the muscle redundancy problem (i.e., with the problem that human-body contains more muscles than what would be typically needed to drive various body joints). The results obtained show that various seat adjustments (e.g., back-rest inclination, seat-pan horizontal track position, etc.), driver''s back supports (e.g., presence/absence of lumbar support) and the nature of seat upholstery (e.g., fabric vs. vinyl) can have complex influence on the muscle activation, joint forces, soft-tissue contact normal and shear stresses, all of which not only affect the comfort perception of the driver but also their feel of fatigue. Subsequently, the results of the present work along with relevant public-domain literature findings (e.g., subjective driving-fatigue assessments provided by human test subjects and human-body/seat contact-force measurements) are used to construct a preliminary long-distance driving-fatigue function. Relevance to industry: it is argued that the computer-aided engineering analysis introduced in the present work should help speed-up the design of new high-comfort car seats. These seats are currently being mainly designed using empiricism, legacy knowledge and extensive, time-consuming and costly prototyping and experimental/field testing. [Copyright &y& Elsevier]
Ait El Menceur, Mohand Ouidir, Pudlo, Philippe, Gorce, Philippe, Thévenon, André, and Lepoutre, François-Xavier
International Journal of Industrial Ergonomics. Nov2008, Vol. 38 Issue 11/12, p1078-1087. 10p.
ERGONOMICS, AUTOMOBILE industry, HUMAN mechanics, PROSTHETICS, AUTOMOBILE driving, and OLDER people
Abstract: This paper presents a panorama of ingress/egress movement strategies adopted by young and elderly persons with or without prosthesis(es). The experiments were conducted within the national French project HANDIMAN (RNTS 2004) that aims at integrating the phase of discomfort evaluation in the ingress/egress movement for elderly and/or disabled population. The HANDIMAN project experimental protocol aimed to gather kinematic and dynamic data of the ingress/egress movement of 41 test subjects. The movements were realized on four stripped vehicles covering a wide range of the vehicle types present in the trade. Two big families of ingress and egress movements were identified, whether the subjects enter (or leave) a vehicle by laying on one foot or by laying on two feet. Eight ingress and egress movement strategies were identified within these two families (5 ingress strategies and 3 egress strategies). Four of our strategies are similar to the ones identified by Andreoni et al. [1997. New approaches to car ergonomics evaluation oriented to virtual prototyping. EURO-BME Course on Methods & Technologies for the Study of Human Activity & Behaviour, Italy, March]. This paper will specify these identified strategies with respect to the implied population and to the tested vehicles. No strategy can systematically be assigned to a specific person. However, there were some dominating trends for some subjects. Relevance to industry: This study can aid ergonomists and car manufacturers to understand and to evaluate the ingress/egress movement ease and discomfort for young and elderly persons with or without prosthesis(es). The vehicle dimensions could be adapted according to the ingress and egress movement strategies identified for the targeted population. The identified strategies can also enhance digital human models (DHMs). [Copyright &y& Elsevier]