1. Department of Automotive Engineering, Engineering Faculty, Universitas Negeri Padang, Padang Indonesia
2. Department of Mechanical Engineering, Politeknik Negeri Semarang, Semarang, Indonesia
3. Department of Electrical engineering, University of Science and Technology of Southern Philippines Cagayan de Oro City, Philippines
4. Departement of Electrical Engineering, Southern Taiwan University of Science and Technology, No.1, Nantai St., Tainan City 710301, Taiwan