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 system for providing assistance to a user of a surgical robot system, the system comprising: a surgical robot system comprising at least one surgical robot having a base, and an arm extending from the base to an attachment for an instrument, the arm comprising a plurality of joints whereby the configuration of the arm can be altered; and an assistance module comprising a list of steps of a task for which procedural assistance can be provided, the assistance module being configured to:receive, while the surgical robot system is being used to perform the task, status data indicating a status of the surgical robot system;determine, from the status data, whether the surgical robot system is in a procedural assistance state, the surgical robot system being in a procedural assistance state when the surgical robot system is being, or, is about to be, used to perform one of the steps of the task for which procedural assistance can be provided; and in response to determining that the surgical robot system is in a pr

Abstract: A surgical robotic system, comprising: a surgical robot; a user input device coupled to the surgical robot and manipulatable by a user to control operation of the surgical robot, the user input device comprising one or more sensors configured to collect data as the user manipulates the user input device; a processor unit configured to: analyse the collected data to determine whether a parameter associated with the operation by the user of the surgical robot has a desired working value; and generate an output signal indicating responsive action is to be taken in response to determining from the collected data that the parameter does not have a desired working value.

Abstract: A surgical robotic system for augmenting a representation of a surgical site at which a surgical procedure can be carried out, the system comprising: a display configured to display part or all of a representation of at least a portion of a surgical site; a controller comprising an input device, whereby the input device can control an indicator on the display, the controller being configured to output an augmentation signal in response to user input relating to the representation; and a processor configured to receive the augmentation signal and, in response to the received augmentation signal, to augment the representation of the surgical site.

Abstract: A motor arrangement comprising: motor having a rotor, a stator, and a plurality of windings mounted on one of the rotor and the stator for acting on the other of the rotor and the stator, and a plurality of inputs coupled to the windings; and control circuit configured to operate in a riving mode in which it dynamically energises the windings via the motor inputs so as to cause the rotor to rotate relative to the stator, the control circuit being further configured to operate in a braking mode in which it continually connects at least a first and a second one of the windings to a common rail to form a closed current path to induce braking of the rotor relative to the stator, wherein the control circuit is configured to enter the braking mode in response to a trigger exogenous to the motor indicative of a fault condition.

Abstract: A position sensing arrangement for sensing the position of a revolute joint of an articulated structure. The position sensing arrangement comprises a disc and a magnetic sensor assembly. The disc comprises a first magnetic ring with m magnetic pole pairs, and a second magnetic ring with n magnetic pole pairs, where m and n are co-prime, and a mounting arrangement by which the disc is mountable to a magnetisation jig during manufacture and the articulated structure during operation, the mounting arrangement permitting the disc to be mounted to the magnetisation jig and articulated structure in a single orientation only. The magnetic sensor assembly comprises a first magnetic sensor array for detecting the magnetic pole pairs of the first magnetic ring, and a second magnetic sensor array for detecting the magnetic pole pairs of the second magnetic ring.

Abstract: A control system for a surgical robotic system, the surgical robotic system comprising a remote surgeon console and an articulated surgical robot arm comprising a series of joints extending from a base to a terminal end for attaching to an articulated surgical instrument. The control system comprises a central controller communicatively coupled to and remotely located from an arm controller of the surgical robot arm, the central controller also communicatively coupled to a surgeon input device of the surgeon console.

Abstract: A medical device is described having a handle and an end effector coupled to the handle. The end effector has at least one electrode for providing electrical signals to a tissue or vessel to be treated. An RF drive circuit is provided for generating an RF drive signal that is applied to the end effector electrode. The RF drive circuit includes a resonant circuit and a frequency controller is used to vary the frequency of a signal passed through the resonant circuit in order to control the power supplied to the end effector electrode.

Abstract: Methods and systems for automatically augmenting an endoscope video for a task based on status data that describes the status of a surgical robot system that was used to at least partially perform the task. The system comprises an event detector and an augmenter. The event detector is configured to: receive the status data; and identify one or more patterns in the status data that indicate an event occurred during the task. The augmenter is configured to receive an endoscope video captured during the task, the endoscope video being time synchronised with the status data; and in response to the event detector identifying a pattern in the status data that indicates an event occurred, automatically augment metadata that forms part of or is associated with the endoscope video with information identifying the event and the time the event occurred with respect to the endoscope video.

Abstract: A method of assembling a position sensing arrangement for sensing the position of a revolute joint of an articulated structure. The position sensing arrangement comprises a magnetic sensor assembly and a disc having a first magnetic ring with j magnetic pole pairs and a second magnetic ring with k magnetic pole pairs. A boundary of the disc is constrained by the articulated structure.

Abstract: A method of correcting a position reading from a position sensing arrangement. The position sensing arrangement is suitable for sensing the position of a revolute joint of an articulated structure, and comprises a disc having a magnetic ring with magnetic pole pairs and a magnetic sensor assembly comprising a magnetic sensor array for detecting the magnetic pole pairs of the magnetic ring.

Abstract: A circuit for sensing the driving current of a motor, the circuit comprising: a driver configured to generate a driving current for each phase of a multiple-phase motor, the instantaneous sum of all the driving currents being zero; a current sensor for each phase of the multiple-phase motor, each current sensor configured to measure the driving current of that phase and comprising a plurality of current sensor elements arranged with respect to each other such that each current sensor element has the same magnitude of driving current systematic error due to magnetic fields external to the driving current to be measured; and a controller configured to, for each phase of the multiple-phase motor, generate an estimate of the driving current of that phase to be the measured driving current of that phase minus 1/n of the total of the measured driving currents for all phases, n being the number of phases of the multiple-phase motor.

Abstract: A medical device is described having a handle, a shaft coupled to the handle and an end effector coupled to the shaft. In one embodiment, the device includes an ultrasonic transducer and is arranged so that ultrasonic or electrical energy can be delivered to a vessel or tissue to be treated. Various novel sensing circuits are described to allow a measure of the drive signal to be measured and fed back to a controller. An active fuse circuit is also described for protecting one or more batteries of the device from an over-current situation.

Abstract: A medical device is described having a handle, a shaft coupled to the handle and an end effector coupled to the shaft. In one embodiment, the device includes an ultrasonic transducer and is arranged so that ultrasonic or electrical energy can be delivered to a vessel or tissue to be treated. Various novel sensing circuits are described to allow a measure of the drive signal to be measured and fed back to a controller. An active fuse circuit is also described for protecting one or more batteries of the device from an over-current situation.

Abstract: A medical device is described having a handle, a shaft coupled to the handle, an end effector coupled to the shaft and an ultrasonic transducer coupled to the end effector for delivering ultrasonic energy to tissue or a vessel to be treated. A drive circuit is provided for generating a drive signal that is applied to the ultrasonic transducer. In one embodiment, the drive circuit includes a resonant circuit and a controller that varies the period of the drive signal passed through the resonant circuit in order to control the power supplied to the ultrasonic transducer.

Abstract: A robot arm comprising a joint mechanism for articulating one limb (310) of the arm relative to another limb (311) of the arm about two non-parallel rotation axes (20, 21), the mechanism comprising: an intermediate carrier (28) attached to a first one of the limbs by a first revolute joint having a first rotation axis and to a second one of the limbs by a second revolute joint having a second rotation axis; a first drive gear (33) disposed about the first rotation axis and fast with the carrier, whereby rotation of the carrier relative to the first limb about the first rotation axis can be driven; a second drive gear (37) disposed about the second rotation axis and fast with the second one of the limbs, whereby rotation of the second one of the limbs about the second rotation axis relative to the carrier can be driven; at least one of the first and second drive gears being a sector gear.

Abstract: A circuit for sensing the driving current of a motor, the circuit comprising: a driver configured to generate a driving current for each phase of a multiple-phase motor, the instantaneous sum of all the driving currents being zero; a current sensor for each phase of the multiple-phase motor, each current sensor configured to measure the driving current of that phase and comprising a plurality of current sensor elements arranged with respect to each other such that each current sensor element has the same magnitude of driving current systematic error due to magnetic fields external to the driving current to be measured; and a controller configured to, for each phase of the multiple-phase motor, generate an estimate of the driving current of that phase to be the measured driving current of that phase minus 1/n of the total of the measured driving currents for all phases, n being the number of phases of the multiple-phase motor.

Abstract: Methods and systems for automatically augmenting an endoscope video for a task based on status data that describes the status of a surgical robot system that was used to at least partially perform the task. The system comprises an event detector and an augmenter. The event detector is configured to: receive the status data; and identify one or more patterns in the status data that indicate an event occurred during the task. The augmenter is configured to receive an endoscope video captured during the task, the endoscope video being time synchronised with the status data; and in response to the event detector identifying a pattern in the status data that indicates an event occurred, automatically augment metadata that forms part of or is associated with the endoscope video with information identifying the event and the time the event occurred with respect to the endoscope video.

Abstract: A method of correcting a position reading from a position sensing arrangement. The position sensing arrangement is suitable for sensing the position of a revolute joint of an articulated structure, and comprises a disc having a magnetic ring with magnetic pole pairs and a magnetic sensor assembly comprising a magnetic sensor array for detecting the magnetic pole pairs of the magnetic ring.

Abstract: A robot arm comprising a joint mechanism for articulating one limb (310) of the arm relative to another limb (311) of the arm about two non-parallel rotation axes (20, 21), the mechanism comprising: an intermediate carrier (28) attached to a first one of the limbs by a first revolute joint having a first rotation axis and to a second one of the limbs by a second revolute joint having a second rotation axis; a first drive gear (33) disposed about the first rotation axis and fast with the carrier, whereby rotation of the carrier relative to the first limb about the first rotation axis can be driven; a second drive gear (37) disposed about the second rotation axis and fast with the second one of the limbs, whereby rotation of the second one of the limbs about the second rotation axis relative to the carrier can be driven; at least one of the first and second drive gears being a sector gear.