Yusaku Fujii

Learn More
Currently, in the whole world, enormous electric energy is consumed by the street lights, which are automatically turn on when it becomes dark and automatically turn off when it becomes bright. This is the huge waste of energy in the whole world and should be changed. This paper discusses a smart street light system, whose concept is proposed by Fujii et(More)
A multi-point laser Doppler velocimeter (LDV) using the arrayed waveguide gratings (AWGs) with small wavelength sensitivity (less than 1/10 of that for a conventional LDV without the AWGs) is proposed, in which velocities at different points in the depth direction can be simultaneously measured with compact optical systems. The design and characteristics of(More)
Expert manual workers in factories assemble more efficiently than novices because their movements are optimized for the tasks. In this paper, we present an approach to projecting the hand movements of experts at real size, and real speed and onto real objects in order to match the manual work movements of novices to those of experts. We prototyped a(More)
1 Department of Electronic Engineering, Faculty of Engineering, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515, Japan; E-Mails: takita@el.gunma-u.ac.jp (A.T.); fujii@el.gunma-u.ac.jp (Y.F.) 2 Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesa 10, Bandung 40132, Indonesia; E-Mail:(More)
A frequency estimation method (ZFM: Zero-crossing Fitting Method) for measuring time-varying single frequency is applied to determine the velocity of the mass for a space scale. The difference between the ZFM and conventional zero-crossing method used in typical electric frequency counters is discussed. The velocity derived from estimated Doppler frequency(More)
A method of generating and measuring static small forces at the micro-Newton level is proposed. In the method, the down-slope component of gravity acting on a mass on an inclined plane is used as a static force. To realize a linear motion of the mass with a small friction, an aerostatic linear bearing is used. The forces acting on the mass, such as the(More)