Benjamin W. Schafer

Learn More
The objective of this paper is to provide technical background and illustrative examples for stability analysis of cold-formed steel members using the conventional and constrained finite strip methods as implemented in the open source program CUFSM. Numerical stability analysis combined with an accurate identification of the buckling modes is an enabling(More)
The tip asymmetry of a bevel-tip needle results in the needle naturally bending when it is inserted into soft tissue. This enables robotic needle steering, which can be used in medical procedures to reach subsurface targets inaccessible by straight-line trajectories. However, accurate path planning and control of needle steering requires models of(More)
The objective of this paper is to provide a review of the Direct Strength Method for cold-formed steel design. The Direct Strength Method was formally adopted in North American design specifications in 2004 as an alternative to the traditional Effective Width Method. The appendix of this paper provides an excerpt from the North American Specification which(More)
The asymmetry of a bevel-tip needle results in the needle naturally bending when it is inserted into soft tissue. In this study we present a mechanics-based model that calculates the deflection of the needle embedded in an elastic medium. Microscopic observations for several needle-gel interactions were used to characterize the interactions at the bevel tip(More)