  As the most essential part of CAD modeling operations, boolean operations on
B-rep CAD models often suffer from errors. Errors caused by geometric precision
or numerical uncertainty are hard to eliminate. They will reduce the
reliability of boolean operations and damage the integrity of the resulting
models. And it is difficult to repair false boolean resulting models damaged by
errors. In practice, we find that the illegal boolean resulting models stem
from the false intersection edges caused by errors. Therefore, this paper
proposes an automatic method based on set reasoning to repair flawed structures
of the boolean resulting models by correcting their topological intersection
edges. We provide a local adaptive tolerance estimation method for each
intersection edge based on its geometric features as well as its origin. Then,
we propose a set of inference mechanisms based on set operations to infer
whether a repair is needed based on the tolerance value and how to correct the
inaccurate intersection edge. Our inference strategies are strictly proven,
ensuring the reliability and robustness of the repair process. The inference
process will transform the problem into a geometric equivalent form less
susceptible to errors to get a more accurate intersection edge. Since our
inference procedure focuses on topological features, our method can repair the
flawed boolean resulting models, no matter what source of errors causes the
problem.
