**Author details**

Junfeng Xiong1,2, Feng Gu1 , Decai Li1 , Yuqing He1\* and Jianda Han1

\*Address all correspondence to: heyuqing@sia.cn

1 State Key Laboratory of Robotics of Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang, China

2 University of Chinese Academy of Sciences, Beijing, China
