Abstract: Software tools, methods and apparatus for objectively assessing surgical and medical procedural skills are described. Data corresponding to performance of a manipulative task by a subject is modeled using Markov modeling techniques and compared with stored models corresponding to each of a plurality of proficiency levels. A particular proficiency level is selected based on proximity of the subject data relative to each of the stored models.

Abstract: This document discusses, among other things, a mechanism for providing motion having two degrees of freedom and centered on a single point within a sphere. Methods to design the mechanism consistent with specified parameters are also described.

Abstract: Methods are provided for stabilizing a haptic interface of a computer-controlled one-port virtual-reality system or a two-port teleoperation system comprising a robot manipulator. “Stabilizing” means to reduce the sense of vibration in a haptic interface. A Passivity Observer is computed to measure the amount of energy produced at the haptic interface, and a Passivity Controller is calculated to damp or absorb excess energy which causes the sense of vibration. This invention also provides a “filter,” i.e. a threshold function which returns zero velocity if the computed estimated velocity is less than a small predetermined value, which may be applied to estimated velocities determined in impedance-based methods of this invention so as to remove noise in the velocity estimate. To improve speed of reaction of the systems, this invention also provides methods for resetting the Passivity Observer to zero when it has been too positive for too long a period of time.

Abstract: The invention relates to a haptic control device by which an operator is provided with visual as well as tactile feedback. In one embodiment, the operator interacts with a control system via a display panel. Based on the nature of the operator inputs, the control system can provide the operator with both a visual output via the display panel, as well as tactile feedback.

Abstract: A flat-coil actuator embedded in a linkage of a mechanical interface for a force feedback device. The linkage rotates about an axis, where a flat coil is embedded in the linkage between two ends or connection points of the linkage. Magnets are positioned parallel to the flat coil, where a force is produced on the linkage when a current is flowed in the coil. An embedded position sensor, such as an optical encoder, can be coupled to the linkage. A force feedback device incorporating the flat-coil actuator includes a user manpulandum, where the linkage is coupled between a ground and the user manipulandum. Other linkages can also be coupled to the actuator to provide mechanisms such as a five-bar linkage mechanism.

Abstract: Methods are provided for stabilizing a haptic interface of a computer-controlled one-port virtual-reality system or a two-port teleoperation system comprising a robot manipulator. “Stabilizing” means to reduce the sense of vibration in a haptic interface. A Passivity Observer is computed to measure the amount of energy produced at the haptic interface, and a Passivity Controller is calculated to damp or absorb excess energy which causes the sense of vibration. This invention also provides a “filter,” i.e. a threshold function which returns zero velocity if the computed estimated velocity is less than a small predetermined value, which may be applied to estimated velocities determined in impedance-based methods of this invention so as to remove noise in the velocity estimate. To improve speed of reaction of the systems, this invention also provides methods for resetting the Passivity Observer to zero when it has been too positive for too long a period of time.

Abstract: A high precision, small volume fluid processing system employs open ended capillary tubes to meter, aliquot and mix small volumes of sample fluid and reagents. The system has an automatic mechanism for moving the capillary tubes as well as automated sub-systems for incubating and mixing fluids within the capillary tubes.

Abstract: A pen-based direct-drive manipulator enables precision manipulation and force display of a control point within three degrees of freedom. The control point exhibits substantially no backlash, very low friction and very low inertia making it useful as a force display. The manipulator also has a very high force generation bandwidth allowing high frequency force components to be displayed. A parallel actuator structure controls motion over two degrees of freedom in a horizontal plane. The parallel structure is a redundant structure including three chains in parallel coupled at the control point. The redundant structure provides a uniform force capability throughout the manipulator workspace. A pair of rotational actuators rotate the parallel structure about an axis to approximate a linear motion along a third axis. The rotational actuators provide a third degree of freedom for the control point. Motion about the third axis is substantially decouple from motion about the horizontal plane.

Abstract: A substantially balanced, five-axis, direct drive mini-robot provides repeatable micro-manipulation to micron precision. Dynamic forces of each link are nearly decoupled from the dynamic forces of remaining links. The robot is generally formed as a shoulder, arm and wrist assembly. At the shoulder a linear actuator drives the robot in a linear horizontal movement along a first axis (e.g., z axis). Two additional actuators at the shoulder provide revolute motion to rotate the arm in an xz plane (e.g., for lateral motion) and a yz plane (e.g., for vertical motion), respectively. A fourth actuator provides rotational motion to move an end-effector (manipulator) at the wrist through a yaw motion. A fifth actuator, positioned at the shoulder and linked to the wrist, provides rotational motion to move the end-effector through a pitch motion.

Abstract: Apparatus for multiplexing switch state signals comprises a plurality of switches and parallel weighted resistors connected in series between circuit ground and a node at a utilization device. The resistors are weighted as a function of a power of the same base, such as the power of the base 2, for coding the multiplexed switch state signals. A constant current source connected between the node and circuit ground drives current over a single cable conductor through the resistor. Each switch may be independently closed to change the switch state voltage signals multiplexed to the node. An analog-to-digital converter connected between the node and circuit ground demultiplexes the switch state signals received at the node and provides a switch state signal at each analog-to-digital output corresponding to the state of the switches at the moment.

Abstract: A pen-based direct-drive manipulator enables precision manipulation and force display of a control point within three degrees of freedom. The control point exhibits substantially no backlash, very low friction and very low inertia making it useful as a force display. The manipulator also has a very high force generation bandwidth allowing high frequency force components to be displayed. A parallel actuator structure controls motion over two degrees of freedom in a horizontal plane. The parallel structure is a redundant structure including three chains in parallel coupled at the control point. The redundant structure provides a uniform force capability throughout the manipulator workspace. A pair of rotational actuators rotate the parallel structure about an axis to approximate a linear motion along a third axis. The rotational actuators provide a third degree of freedom for the control point. Motion about the third axis is substantially decouple from motion about the horizontal plane.