Fig. 5.

The paths generated by the SMR planner prior to inserting each needle show that both the small and large needles can reach the target while avoiding the obstacles with only one bevel flip. The large needle is thicker, which requires a larger pre-bend at the tip to achieve a similar radius of curvature as the small needle. However, the larger pre-bend causes a discontinuity in the path when the needle rotates. This illustration is an ideal case, but the needle motion varies, so the needle frequently deviates from this path. The inset shows the standard configuration small needle inserted into the artificial tissue.