1. Morley T, Wallace D. Roll-pitch-roll-yaw surgical tool. US Patent 6,676,684; January 13 2004.
2. Multidisciplinary approach for developing a new minimally invasive surgical robotic system;Lum,2006
3. A novel surgical robot design: minimizing the operating envelope within the sterile field;Dachs,2006
4. Disturbance observer-based motion control of direct drive motors;Komada;IEEE Trans Energy Convers,1991
5. Sensorless torque estimation using adaptive kalman filter and disturbance estimator;Lee,2010