Estimation of model parameters for steerable needles

Abstract— Flexible needles with bevel tips are being developed as useful tools for minimally invasive surgery and percutaneous therapy. When such a needle is inserted into soft tissue, it bends due to the asymmetric geometry of the bevel tip. This insertion with bending is not completely repeatable. We characterize the deviations in needle tip pose (position and orientation) by performing repeated needle insertions into artificial tissue. The base of the needle is pushed at a constant speed without rotating, and the covariance of the distribution of the needle tip pose is computed from experimental data. We develop the closed-form equations to describe how the covariance varies with different model parameters. We estimate the model parameters by matching the closed-form covariance and the experimentally obtained covariance. In this work, we use a needle model modified from a previously developed model with two noise parameters. The modified needle model uses three noise parameters...

• Type: Journal
• Year: 2010
• Where: ICRA
• Authors: Wooram Park, Kyle Brandon Reed, Allison M. Okamura, Gregory S. Chirikjian
• Keywords: Covariance, ICRA 2010, Modified Needle Model, Needle Model, Robotics