1. Universidad Autónoma de Bucaramanga,Control and Mechatronic Research Group,Mechatronic Engineering Dept.
2. the Barcelona East School of Engineering (EEBE), Universitat Politècnica de Catalunya (UPC), Institute for Bioengineering of Catalonia (IBEC) - The Barcelona Institute of Science and Technology,CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN),Automatic Control Dept. (ESAII),Barcelona,Spain,16.08019