Submitted on: 12 September 2009.
Revised on: 24 October 2009.
Accepted on: 29 October 2009.
ROBOTICS AND AUTONOMOUS SYSTEMS
http://reply.papertrans.cn/3/273/27288/27288-32.png
http://reply.papertrans.cn/3/273/27288/27288-33.png
Submitted on: 23 June 2014.
Revised on: 05 August 2014.
Accepted on: 28 August 2014.
ROBOTICS AND AUTONOMOUS SYSTEMS
http://reply.papertrans.cn/3/273/27288/27288-35.png
http://reply.papertrans.cn/3/273/27288/27288-36.png