2013 Summer Project Week:Robot Control

Key Investigators

• Autonomous University of the State of Mexico : Adriana Vilchis-Gonzalez, Juan-Carlos Avila-Vilchis
• Brigham and Women's Hospital/Harvard Medical School: Sonia Pujol

Objective

The purpose of this project is to explore the use of 3D-Slicer libraries to control the orientation of a puncture robot that is compatible with MR or CT (Magnetic Resonance or Computed Tomography) environments. The purpose of the robot concerns the orientation of a needle holder and to reach an internal organ to perform therapies or biopsies, for instance. The robot can perform puncture on the human thoracic and abdominal regions and is made of materials that allow its use in RM or CT environments. In this context, a mathematical model that represents the puncture process has been developed and can be used to define new control strategies that, in combination with 3D-Slicer medical images, will perform a puncture under minimal invasion criteria.

Approach, Plan

The approach in this context concerns the application of OpenIGTLink to send: (1) From the robot controller to the 3D Slicer scene, the real needle tip position and needle holder orientation values (rectangular coordinates and Eulers angles, for instance) defined by a homogeneous transformation matrix associated to the puncture robot configuration to visualize in the 3D Slicer scene, the needle inside the body and (2) From the 3D Slicer scene to the robot controller, the difference between the target position and the needle tip position (feedback error) to perform a predefined robot control strategy.

Progress

After discussions with some people (Sonia pujol, Junichi Tokuda, Sebastian Tauscher) a better understanding of how 3D Slicer and, in particular, OpenIGTLink can be related to a physical device to perform tracking tasks and a list of tasks to do: coordinate systems definition and associated transformations (LPS vs. RAS), calibration, code writing and maybe the modification of the first idea by the use of a haptic component to perform control tasks that will be operated by the physician. The definition of reachable/accessible zones could be considered to be part of the control strategy through bounded neighborhoods where the robot will be allowed to place the needle.

Progress