Mitsubishi Electric Research Laboratories, Inc.

Mitsubishi Electric Information Technology Center America, Inc (ita)

Jeffrey Michael Wendlandt

Frederick Marshall Morgan

Dwight Allan Meglan

An actuator is used in a surgical simulation system that simulates the catheterization of cardiac or peripheral vasculature. The simulation system provides haptic feedback to a user of a catheter or similar elongated object coupled to the system. The actuator includes sensors that generate sense signals indicative of axial translation and rotation of the object by the user. The sense signals are provided to a workstation executing a simulation program. In response to the sense signals, the workstation calculates axial forces and torques to be applied to the object as haptic feedback to the user, and generates drive signals representing the calculated axial forces and torques. Mechanisms within the actuator respond to the drive signals by applying corresponding axial force and torque to a rigid tube that is mechanically coupled to the object. One embodiment of the actuator includes a carriage assembly for holding the rigid tube between a pair of opposed pinch wheels. The carriage assembly rotates to rotate the object about its longitudinal axis, and the pinch wheels rotate to translate the object axially. Another actuator embodiment includes a first bearing mounted on a rotary actuator and a second bearing mounted on a sliding linear actuator. The rigid tube has a square cross section for secure engagement by the second actuator. The linear actuator grips the tube and allows it to freely rotate about its longitudinal axis.

Actuator for independent axial and rotational actuation of a catheter or similar elongated object

A master/slave system is used for performing a surgical procedure such as theterization of cardiac or peripheral vasculature. Movements of catheters or similar tools within a patient are remotely controlled by a surgeon, and the surgeon receives haptic or tactile feedback caused by the movement of the tools within the patient. The system employs a master actuator with cylindrical controls and a slave actuator that engages the tools. The master actuator and slave actuator are electrically coupled to electrical interface circuitry by drive signals and sense signals. A fluid system is coupled to the slave actuator by fluid-carrying tubes for the delivery of contrast and other solutions to be injected into the vasculature for improved imaging and also to pressurize the balloon on a balloon catheter. The master and slave actuators contain sensors that sense translation and rotation of the controls and tools with respect to their longitudinal axes, and provide sense signals indicative of these motions to the interface circuitry. The master and slave actuators also contain motors respectively engaging the controls and tools to cause translational and rotational movement of these components in response to the drive signals generated by the interface circuitry. The interface circuitry contains a processor executing a master/slave control program via which the relative positions of each control and the corresponding tool are made to track each other. The control program can optionally implement force scaling, position scaling, tremor reduction, and other features to enhance the system's performance.

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Cambridge, MA, United States of America

Jeffrey Michael Wendlandt