1. Dept. of Engineering Physics, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung 40132, Indonesia.
2. Smart Robot Center, Dept. of Aerospace Information Engineering, Konkuk Univ., Seoul, Korea. (corresponding author).
3. School of Electrical Engineering and Informatics, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung 40132, Indonesia.