Current Research Area
Product
Complexity
During the manufacturing analysis of a product, special
attention must be paid to the shape complexity. Current analyses
require the designer to follow manufacturing process charts, but
these are mainly subjective.
Complexity
Part
count reduction vs. Complexity
Current DFA methodologies encourage part count reduction, but
care must be taken to ensure that benefits of reduced part count
are not outweighted by manufacturing costs of the new
components.
Symmetry Detection
Identification of likely insertion trajectories for Feeding
Analysis
Symmetry Detection Overview
Due to its prominence in many geometric analyses, the detection
of symmetry was an important area for geometric reasoning research
in the Ophir project. This
resulted in an algorithm for symmetry detection, which identifies
the symmetric and asymmetric elements of a component or
subassembly. The technique relies upon the availability of loops in
a boundary representation CAD model. A simple five-step algorithm
based on sorting and comparison of bounded surface area enables
symmetric portions of the boundary to be identified. The technique
generates a set of symmetry axes, ranked by their relative
importance, and identifies the groups of boundary elements that are
symmetric with respect to each axis found.
Figure 1. (Simple) Typical symmetry
detection
The major benefit of the procedure is that the identification of
exact symmetries within a component is unaffected by the asymmetric
portions of the boundary. In addition, the orientation of the
component need not be predefined. The symmetry detection algorithm
has been tested on a representative range of models demonstrating
consistent and reliable results, and will thus be refined for use
in the ‘Sandpit’ environment. Since symmetry plays such a
significant role in geometric evaluations for assembly this
algorithm will also be adapted and extended for further analyses.
In particular, this approach may be adapted for the calculation of
symmetry/direction of insertion.
Figure 2. Symmetry Detection
(Ignoring small asymmetries)