This paper focuses on autonomous movements to aid the surgeon to perform certain tasks. Robotic assistants have solved the drawbacks of Minimally Invasive Surgery (MIS) and provide additional skills to the surgeons. However, some authors argue that these systems could lengthen the operating time. The solution is the automation of certain maneuvers that help the surgeon during a surgical maneuver. This work proposes control architecture for a surgical robot capable of performing autonomous movements. In this way, a trajectory planner based on a behavior concept computes the required velocity vector of the surgical instrument hold by the robot. This planner has been implemented and tested on the control architecture of the surgical assistant CISOBOT, designed and developed at the University of Malaga.