This paper proposes a method for interfacing a force-feedback device of type PHANToM to a spring-damper model of the human thigh. The model was defined from experimental data and it is simulated using implicit integration. The main difficulty encountered is that while the PHANToM needs to receive the force values at a rate of 1 KHz, the physical model runs at a maximum speed of 100 Hz. Supplying forces at this frequency leads to unrealistic vibration in the force feedback. The novelty of our approach is the use of a local model supplying reliable force values at a high frequency. The purpose of this work is to contribute for the implementation of an echographic simulator with force-feedback.

This paper presents a new algorithm for computing the minimum distance between convex polyhedras. The algorithm of Gilbert-Johnson-Keerthi (GJK) and the algorithm of Lin-Canny (LC) are well-known fast solutions to the problem. We show how a mix between LC's idea and the GJK's algorithm can be used to solve the problem. In our algorithm, we use local methods to calculate the distance between features and new "updating" conditions to add stability. These new conditions enable one to ensure more stability when compared to GJK. We also modify our terminating conditions to add robustness to our approach. Our experiments also show that the expected running time of our approach is constant, independent of the complexity of the polyhedra. We present some comparisons of our method with GJK.

Proposes a mass-spring model of a human thigh based on real data acquired. It addresses both the difficulties of determining the parameters of this model to fit the measurements and the computational demands. Implicit integration is used to update the model through time. The motivation behind this work is to provide accurate force-feedback for an echographic simulator that could be used to train practitioners to detect a thrombosis.