1. School of Electrical Engineering and Automation, Hefei University of Technology, Hefei, China
2. LAETA/INEGI, Faculty of Engineering, University of Porto, Porto, Portugal
3. School of Mathematics, Anhui University, Hefei, China
4. College of Automation, Zhongkai University of Agriculture and Engineering, Guangzhou, China
5. Mechatronics, Embedded Systems and Automation Lab, University of California, Merced, CA, USA