| Volume 25 Issue 5/6 - Publication Date: 1 May/June 2006 |
| Special Issue on the Ninth International Symposium
on Experimental Robotics, 2004 |
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| Nonholonomic Modeling of Needle
Steering |
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| R. J. Webster III, J.
S. Kim, N. J. Cowan, G. S. Chirikjian, and A. M. Okamura
Department of Mechanical Engineering, The Johns Hopkins University |
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| As a flexible needle with a
bevel tip is pushed through soft tissue, the asymmetry of the tip causes
the needle to bend. We propose that, by using nonholonomic kinematics, control,
and path planning, an appropriately designed needle can be steered through
tissue to reach a specified 3D target. Such steering capability could enhance
targeting accuracy and may improve outcomes for percutaneous therapies,
facilitate research on therapy effectiveness, and eventually enable new
minimally invasive techniques. In this paper, we consider a first step toward
active needle steering: design and experimental validation of a nonholonomic
model for steering flexible needles with bevel tips. The model generalizes
the standard three degree-of-freedom (DOF) nonholonomic unicycle and bicycle
models to 6 DOF using Lie group theory. Model parameters are fit using experimental
data, acquired via a robotic device designed for the specific purpose of
inserting and steering a flexible needle. The experiments quantitatively
validate the bevel-tip needle steering model, enabling future research in
flexible needle path planning, control, and simulation. |
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| Multimedia Key |
= Video |
 = Data |
= Code |
= Image |
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Extension |
Type |
Description |
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1 |
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Example
1: Video of a robot designed to insert flexible needles. (1.9
MB) |
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2 |
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Example 2: Demonstrates the asymmetric bevel tip and the superelasticity
of nitinol needles. (2.9 MB) |
| 3 |
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Example
3: Video of experiments in rubber phantoms with model-based simulations.
(2.1 MB) |
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