This paper presents an automatic compensation algorithm for needle tip displacement in order to keep the needle tip always fixed at the skin entry point in the process of needle orientation in robot-assisted percutane...This paper presents an automatic compensation algorithm for needle tip displacement in order to keep the needle tip always fixed at the skin entry point in the process of needle orientation in robot-assisted percutaneous surgery. The algorithm, based on a two-degree-of-freedom （2-DOF） robot wrist （not the mechanically constrained remote center of motion （RCM） mechanism） and a 3-DOF robot ann, firstly calculates the needle tip displacement caused by rotational motion of robot wrist in the arm coordinate frame using the robotic forward kinematics, and then inversely compensates for the needle tip displace- ment by real-time Cartesian motion of robot arm. The algorithm achieves the function of the RCM and eliminates many mechanical and virtual constraints caused by the RCM mechanism. Experimental result demonstrates that the needle tip displacement is within 1 inm in the process of needle orientation.展开更多
文摘This paper presents an automatic compensation algorithm for needle tip displacement in order to keep the needle tip always fixed at the skin entry point in the process of needle orientation in robot-assisted percutaneous surgery. The algorithm, based on a two-degree-of-freedom （2-DOF） robot wrist （not the mechanically constrained remote center of motion （RCM） mechanism） and a 3-DOF robot ann, firstly calculates the needle tip displacement caused by rotational motion of robot wrist in the arm coordinate frame using the robotic forward kinematics, and then inversely compensates for the needle tip displace- ment by real-time Cartesian motion of robot arm. The algorithm achieves the function of the RCM and eliminates many mechanical and virtual constraints caused by the RCM mechanism. Experimental result demonstrates that the needle tip displacement is within 1 inm in the process of needle orientation.
