Projects in Progress

• Force feedback controller based on fuzzy-rules emulated networks and Hertzian contact with ultrasound

A novel force controller which combines a neuro-fuzzy algorithm and a contact ultrasonic probe was developed.The fuzzy rules emulated network (FREN) has a control algorithm structure based on fuzzy IF–THEN rules. The contact probe is constructed of an ultrasonic transducer and a forcesensor integrated on a semi- spherical head controlled by a robotic system of four degrees of freedom. The system was tested on samples with different mechanical properties incluidng biological.

• Implementation of efficient trajectories for an ultrasonic scanner using chaotic maps

Typical ultrasonic methodology for nondestructive scanning evaluation uses systematic scanning paths. In many cases, this approach is time inefficient and also energy and computational power consuming. We are developing a methodology for the scanning of defects using an ultrasonic echo-pulse scanning technique combined with chaotic trajectory generation. This is implemented in a Cartesian coordinate robotic system developed in our lab.

• Ultrasonic Tomography Using Lamb Wave Propagation Parameters

Tomography refers to the cross-sectional imagining of an object from either transmission or reflection data collected by illuminating the object from different directions. In this project, an ultrasonic tomography system based on Lamb waves, developed in our laboratory was used. We solve the inverse problem of tomography imaging using data collected from ultrasonic plate waves interacting with a discontinuity. The main focus is on improving the quality of tomography maps using two reconstruction techniques (backprojection tomography and Multiplicative Algebraic Reconstruction Technique -MART).