In this research, we will develop a robot platform for disaster response based on Systems Engineering, aiming at promoting research of disaster response robots by opening up the development process and provide it as open source. By using the developed robot platform and the process, users themselves can freely change the performance of the robot based on their own requirements. According to this, researchers will use the suitable robot platform. In this paper, in order to systematically consider various design specifications, we developed the robot prototype by considering decommissioning work for a nuclear accident based on Systems Engineering. Also, we proposed a simplification method of the robot parts for open source hardware to ensure reproducibility.