The objective of the Seoul ubiquitous (smart) city project was to find a method to measure a temperature, a humidity or a noise level in the urban areas. But the problem was that we would need to install a large number of sensors over a broad area and each sensor must be connected to the center-server through wired or wireless network. To solve this problem, we created the MSU (Moving Sensor Unit) which is a useful technical concept that helps with sensing a wide ubiquitous area. It turned out to be a great solution for the sensor problem. In this paper, we will present our MSU of the Grid Friend and introduce the processes of the Requirement Definition, Analysis & Design, Build and Implementation.
