Abeygunawardhana Pradeep Kumara, W., and Toshiyuki Murakami. 2010. “Control of Two Wheel Mobile Manipulator on a Rough Terrain Using Reaction Torque Observer Feedback”. Journal of Automation, Mobile Robotics and Intelligent Systems 4 (1): 56-67. https://www.jamris.org/index.php/JAMRIS/article/view/105.