Universite de technologie de Belfort-Montbeliard

About: Universite de technologie de Belfort-Montbeliard is a education organization based out in Belfort, France. It is known for research contribution in the topics: Coating & Microstructure. The organization has 1087 authors who have published 2593 publications receiving 47819 citations.

A novel approach to modelling and simulating the contact behaviour between a human hand model and a deformable object

Abstract: A deeper understanding of biomechanical behaviour of human hands becomes fundamental for any human hand-operated activities. The integration of biomechanical knowledge of human hands into product design process starts to play an increasingly important role in developing an ergonomic product-to-user interface for products and systems requiring high level of comfortable and responsive interactions. Generation of such precise and dynamic models can provide scientific evaluation tools to support product and system development through simulation. This type of support is urgently required in many applications such as hand skill training for surgical operations, ergonomic study of a product or system developed and so forth. The aim of this work is to study the contact behaviour between the operators' hand and a hand-held tool or other similar contacts, by developing a novel and precise nonlinear 3D finite element model of the hand and by investigating the contact behaviour through simulation. The contact behaviour is externalised by solving the problem using the bi-potential method. The human body's biomechanical characteristics, such as hand deformity and structural behaviour, have been fully modelled by implementing anisotropic hyperelastic laws. A case study is given to illustrate the effectiveness of the approach.

A dissipativity-based approach to traffic signal control for an over-saturated intersection

Abstract: In this paper, using the energy concept, the control of traffic flow by traffic lights on an over-saturated single intersection is addressed. By regarding the flow entry of vehicles as the energy stored in the system, we show that the dissipative system theory can be applied. As a result, a state feedback control law is found in terms of the solution of an associated dissipation equation that renders the system non-accumulative, i.e., to get out of the over-saturation situation. The results of the simulations indicate that our control strategy guarantees a high degree of control benefit.

Residual stresses and final deformation of an alumina coating: Modeling and measurement

Abstract: Mechanical performances of multi-layer coatings are directly affected by thermal history and subsequent residual stress distribution within the sample during thermal spray process. In the present work, a 3D multi-layer model of the plasma spray process was developed to study the thermal and mechanical evolutions of the specimen. The coating build-up was performed by progressive activation of coating layers with a Gaussian distribution profile measured from the corresponding coating. The contribution of sprayed particles to the substrate heating was thus taken into account using a heat flux presenting a Gaussian distribution profile. The decrease of the coating effective properties caused by the presence of porosities and microcracks was investigated by measurement and calculation works. As a result, the temperature evolution, residual stress distribution and final displacement field of the specimen were predicted. At the end of the deposition process, a tensile stress with small magnitude was obtained within the alumina coating. However, the residual stress was turned to a compressive state within the coating after cooling to ambient temperature. A higher cooling rate was found to result in a lower temperature magnitude of the specimen, a lower residual stress within the coating and a lower displacement field of the specimen. The simulated deflection of the specimen was found to agree well with the experimental measurements.

The effect of ZnO addition on the electrochemical properties of the LaNi3.55Mn0.4Al0.3Co0.2Fe0.55 electrode used in nickel–metal hydride batteries

Abstract: The studied electrochemical properties of the LaNi3.55Mn0.4Al0.3Co0.2Fe0.55 alloy showed a rather poor performance. To improve them, ZnO, a doping agent at different small amounts (0, 1, or 2.5 wt%), was added to this base alloy. Then, the prepared electrodes were investigated by various electrochemical techniques. The maximum discharge capacity, obtained after the activation procedure, increased with the rise in ZnO content. The activation, as well as the reversibility of the hydrogen absorption/desorption process, were significantly improved with the addition of ZnO. It was observed that the latter did not affect considerably the stability and the cycling lifetime if added to the electrodes. After 30 charge/discharge cycles, the diffusion coefficients were estimated to be 1.55 × 10−11, 1.30 × 10−11, and 6.05 × 10−11 cm2 s−1, respectively, for ZnO containing 0, 1, and 2.5 wt%. The ZnO catalyzed the kinetics of hydrogen absorption and desorption process thanks to capacity change before and after activation.