Masoud Kalantari received the M.Sc. degree in Mechatronics Engineering from Iran University of Science and Technology (IUST), Tehran, Iran, in 2007. He is currently pursuing Ph.D. studies in Mechanical Engineering with Dr. J. Dagahi from Concordia University and Dr. J. Kovecses from McGill University, Montreal, Canada. He is also engaged in the Center for Intelligent Machines, McGill University. His current research interests include minimally invasive surgery, tactile sensing, and haptics.
Abstract: Detection of hard inclusions within soft tissue in robotic assisted minimally invasive
surgery (MIS), also referred to as laparoscopic surgery, is of great importance, both in
clinical and surgical applications. In clinical applications, surgeons need to detect and
precisely identify the location and size of all growths, whether cancerous or benign, that
are present within surrounding tissue in order to assess the extent and nature of any
future treatment plan. In surgical applications, when any solid matter is being removed,
it is important to avoid accidental injury to surrounding tissues and blood vessels since,
were this to occur, it could then necessitate the need to resort to open surgery. The present
study is aimed at developing a three-dimensional tactile display that provides palpation
capability to any surgeon performing robotic assisted MIS. The information is collected
from two force sensor/pressure matrices and processed with a new algorithm and graphically
rendered. Consequently, the surgeon can determine the presence, location, and the
size of any hidden superficial tumor/artery by grasping the target tissue in a quasidynamic
way. The developed algorithm is presented, and the results for various configurations
of embedded tumor/arteries inside the tissue are compared with those of the finite
element analysis.
Abstract: Semiconductive polymer composites are used in a wide range of sensors and measurement devices. This paper discusses the development of a model and a new theoretical formulation for predicting piezoresistive behavior in semiconductive polymer composites, including their creep behavior and contact resistance. The relationship between electrical resistance and force applied to the piezoresistive force sensor can be predicted by using the proposed theoretical formulation. In order to verify the proposed formulation, the piezoresistive behavior of Linqstat, a carbon-filled polyethylene, was modeled mathematically. In addition, some experimental tests, such as thermo gravitational analysis and SEM, have been performed on Linqstat to find the volume fraction and size of carbon particles, which are essential for modeling. In addition, on a fabricated force sensor using Linqstat, a force versus resistance curve was obtained experimentally, which verified the validity and reliability of the proposed formulation.
