Method for offset-curve generation for sheet-metal design

Offset curves have many applications in computer-aided design and manufacturing. The paper deals with sheet-metal design, where section curves that lie on a design surface must be offset by one metal thickness. Standard techniques for offsetting curves and surfaces are usually too slow for interactive speeds. The paper presents a simple iterative method for computing offset points which can then be splined to generate the offset curve. The method is first developed for the determination of nondegenerate offset curves, and then modifications necessary for the handling of degenerate offset curves are discussed. Implemented examples for simple sheet-metal design using the proposed method are also presented.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30566/1/0000199.pd

Evaluation and derivation of process plans in turning

The objective of this paper is to formalize process planning selection to minimise the total processing time and the total number of processing steps. The study is performed by defining the processes and part description for turned parts. Two examples solved by the two proposed methods are reported. One of them is the derivation of a new plan which can be expressed as a function of the generated plans. The second method is based on the combination of process plans to generate a new plan which conforms optimally to the change in specification.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45881/1/170_2005_Article_BF01351320.pd

Reconstruction of curved solids from two polygonal orthographic views

It has long been known that the 2-view orthographic representation of a mechanical part is ambiguous. Existing literature addresses the recognition/reconstruction of solids (mostly polyhedral solids) from either 1-view (perspective) drawings or from three orthographic views. The paper presents algorithmsfor reconstructing curved solids from only two polygonal orthographic views. First, all the polyhedral solids that correspond to the pair of prespecified orthogonal views are reconstructed, and then the associated third views are developed. Then, for each solid, the three views are analyzed simultaneously, and the authors reason about the possibilities of including circular arcs in the newly generated third view. This corresponds to the inclusion of solids that are bounded by quadrics. Possible application areas include computer-aided design, machine vision and automated inspection systems.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30171/1/0000556.pd

Intuitive procedure for constructing geometrically complex objects using cyclides

In the past, cyclide surfaces have been used effectively for the variable radius blending of natural quadric intersections. However, attempts to use cyclides for constructing realistic, freeform composite surfaces met with rather limited success. The paper presents a simple procedure for creating and manipulating geometrically complex objects using tubular cyclide pieces. The method described is intuitive from the designer's point of view, and it is based on the fundamental definitions and properties of the cyclide. Various practical issues involved in this design procedure are discussed, several extensions of the basic technique are described, and implemented examples are provided.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/31678/1/0000614.pd

Probing Pseudo-Dirac Neutrino through Detection of Neutrino Induced Muons from GRB Neutrinos

The possibility to verify the pseudo-Dirac nature of neutrinos is investigated here via the detection of ultra high energy neutrinos from distant cosmological objects like GRBs. The very long baseline and the energy range from $\sim$ TeV to $\sim$ EeV for such neutrinos invokes the likelihood to probe very small pseude-Dirac splittings. The expected secondary muons from such neutrinos that can be detected by a kilometer scale detector such as ICECUBE is calculated. The pseudo-Dirac nature, if exists, will show a considerable departure from flavour oscillation scenario in the total yield of the secondary muons induced by such neutrinos.Comment: 11 pages, 3figure

Special issue: Mathematical methods for CAD

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/31670/1/0000606.pd

Computer-aided process planning for parallel machining

http://deepblue.lib.umich.edu/bitstream/2027.42/4700/5/bab1475.0001.001.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/4700/4/bab1475.0001.001.tx