Abstract: A locator of a surgical port of a surgical robot system, the surgical robot system comprising an instrument attached to a robot arm, the instrument having an instrument shaft able to pass through the surgical port to a surgical site, the locator comprising: an interface configured to couple to the surgical port; a mechanism configured to permit relative linear and/or rotational motion of the interface and the instrument shaft; and a controller comprising a processor operable to estimate the position of a part of the robot arm, the controller configured to control the mechanism in dependence on the estimated position of the part of the robot arm such that as the robot arm retracts the instrument from the patient, the locator moves the port away from the robot arm and provides a reaction force to keep the port in place.

Abstract: A method for controlling a mechanical system having a plurality of components interlinked by a plurality of driven joints, the method comprising: measuring torques or forces about or at the driven joints and forming a load signal representing the measured torques or forces; receiving a motion demand signal representing a desired state of the system; implementing an impedance control algorithm in dependence on the motion demand signal and the load signal to form a target signal indicating a target configuration for each of the driven joints; measuring the configuration of each of the driven joints and forming a state signal representing the measured configurations; and forming a set of drive signals for the joints by, for each joint, comparing the target configuration of that joint as indicated by the target signal to the measured configuration of that joint as indicated by the state signal.

Abstract: A surgical robot comprising a surgical robot arm and a surgical instrument. The surgical robot arm terminates at its distal end in a drive assembly comprising a first drive interface element. The surgical instrument comprises a shaft, an articulation attached to the distal end of the shaft, and a driving mechanism at the proximal end of the shaft. The articulation is for articulating an end effector, the articulation driveable by at least a first driving element and a second driving element. The driving mechanism comprises a first instrument interface element to which the first driving element is connected and a second instrument interface element to which the second driving element is connected.

Abstract: A robot comprising: a base; a flexible arm extending from the base and having: a plurality of joints whereby the configuration of the arm can be altered, a plurality of drivers arranged to drive the joints to move, and an attachment structure for attaching a tool to the arm; and a control unit configured to control the drivers and to receive inputs from sensors, and operable in a mode in which, whilst a tool is attached to the attachment structure and captive in a port, it: (i) controls the drivers to permit the arm to be reconfigured by the action of an external force applied to the arm so as to cause the tool to be retracted from the port along a longitudinal axis of the tool; and (ii) on receiving sensor input indicating that the arm has been reconfigured so as to cause the tool to be retracted from the port along a longitudinal axis of the tool, controls the drivers to reconfigure the arm so as to agitate the tool transverse to the longitudinal axis of the tool.

Abstract: A method for controlling a mechanical system having a plurality of components interlinked by a plurality of driven joints, the method comprising: measuring torques or forces about or at the driven joints and forming a load signal representing the measured torques or forces; receiving a motion demand signal representing a desired state of the system; implementing an impedance control algorithm in dependence on the motion demand signal and the load signal to form a target signal indicating a target configuration for each of the driven joints; measuring the configuration of each of the driven joints and forming a state signal representing the measured configurations; and forming a set of drive signals for the joints by, for each joint, comparing the target configuration of that joint as indicated by the target signal to the measured configuration of that joint as indicated by the state signal.

Abstract: A surgical robot comprising an articulated arm, the arm having a terminal portion comprising: a distal segment having an attachment for a surgical instrument; an intermediate segment; and a basal segment whereby the terminal portion is attached to the remainder of the arm; a first articulation between the distal segment and the intermediate segment, the first articulation permitting relative rotation of the distal segment and the intermediate segment about a first axis; and a second articulation between the intermediate segment and the basal segment, the second articulation permitting relative rotation of the intermediate segment and the basal segment about a second axis; wherein: the intermediate segment comprises a third articulation permitting relative rotation of the distal segment and the basal segment about third and fourth axes; and the first, second and third articulations are arranged such that in at least one configuration of the third articulation the first and second axes are parallel and the thir