Micro-opto-electro-mechanical systems (MOEMS) micromirror and shutter arrays have gained huge interest in research and applications. Our study starts with an overview on the technological achievements and experimental results of groups that have been working on this field. The main part of our study is revealing the MOEMS micromirror array technology for light steering via smart glazing for buildings. The mirror array is actuated electrostatically and integrated between the panes of insulation glazing. Depending on user activity as well as daytime and season requirements, the MOEMS micromirror arrays shall enable personalized light steering, energy saving, and reduction of CO 2 emission. Technological fabrication of subfield addressing up to 64 fields inside the arrays is presented. Experimental characterization results such as actuation voltages, maximum and minimum transmission, contrast, and energy saving potential are reported. Using an industrial window module fabrication process, a laboratory demonstrator and a function demonstrator have been implemented. Rapid aging tests including vibrations, extreme temperatures, multiple temperature cycles, and long-term electrostatic actuation of micromirror structure were performed to evaluate reliability and lifetime. These results validate extrapolated lifetimes-in future applications as active windows-far beyond 40 years, as well as their robustness during transportation, installation, and against all vibration influences in buildings. © The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

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Repetitive training is of much importance for restoring full-fledged gait ability. At present, task-specific repetitive approach has been proved to be the most effective motor learning concept. In this regard, a gait trajectory guiding device with partial body weight support system can be a solution for gait rehabilitation. This paper presents a complete gait study with an objective to implement the motion of a natural walking pattern in the automated foot-boards of a gait trajectory guiding device. In our developed motion algorithm of foot-boards we have concentrated on adaptation of patient-specific true walking trajectory, determination of variable velocity pattern along different degrees of freedom and time-division for simulating different phases of a complete gait cycle. Gait database, collected from disparate sources and previous gait-studies have been used for kinetic and kinematic analysis of human walking. We have modeled those data based on the previous researches done in this area and adopt them for our motion algorithm. A precise velocity pattern and time-division have been described along different axes so that patient's biofeedback and postural stability in different walking phases can be recorded accordingly and motion-correction of the foot-boards can be done in consecutive cycles through iterative learning control algorithm with the help of motion sensors.

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This article reports the prediction of the theoretical flow curves of polyamide composites by using Vinogradov-Malkin model. Determination of the melt flow index of polymeric materials is the first step to study viscosity-shear rate relationship. The viscosity of the composites at different temperatures were calculated by using the Williams, Landel'a and Ferry (WLF) equation. Other important rheological characteristics were calculated by using appropriate equations. One point method is employed to correlate the changes in viscosity with temperatures. As expected, it is found that incorporation of nanoclay to polyamide 6 (PA6) significantly decreases the Melt Flow Rate of the composites and hence, increases density. Addition of stabilizer further increases density of the PA6/nanoclay composites. The simulations of viscosity curves for PA6 composites were carried out at measurement temperature, 240°C and in the range of 180°C - 350°C with shear rate of 10-1 – 103 1/s. It is found that addition of nanoclay and stabilizer to PA6 decreases viscosity of the composites in the order of PA6/OMMT > PA6 > PA6/I1098 > PA6/OMMT/I1098 > PA6/MMT/I1098 > PA6/MMT. At higher shear rates, viscosity decreases in the same sequence as low shear rates. At further higher shear rates (> 1000 1/s), filler particles are arranged in the flow direction thus exerting no significant effect on viscosity of composites both with and without the stabilizer. During injection moulding in the shear rate ranging from 101 – 104 1/s at 240°C temperature, it is evident that viscosity decreases drastically with increase in shear rate.

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