Development of a dynamic model for bevel-tip flexible needle insertion into soft tissues.

In this paper, we develop a mechanics-based dynamic model for bevel-tip flexible needle insertion into soft tissues. We use Newton-Euler formulation to account for the effect of actuation, friction, tissue interactions, and bevel-tip forces on the needle. The soft tissue deformation is modeled by finite element analysis, whereas the mechanics-based model is used to predict needle deflections due to bevel-tip asymmetry.

On the controllability of dynamic model-based needle insertion in soft tissue.

Soft tissue needle guidance and steering for clinical applications has been an active topic of research in the past decade. Although dynamic feedback control of needle insertion systems is expected to provide more accurate target tracking, it has received little attention due to the fact that most available models for needle-tissue interaction do not incorporate the dynamics of motions. In this paper, we study the controllability of rigid or flexible needles inside soft tissues using mechanical-based dynamic models.