Application of moment invariants in checking the overall dimension of the head cover

Casting auto transmission head cover, because of its structure complex, form special, it is difficult to check the overall dimensions before it is cool, which greatly increase the time of the product, reduce the factory efficiency. In this paper, for the just completed casting products, the moment invariant is used to check the overall dimensions to determine quality, without human testing, which can reduce the time, increase efficiency, improved real-time and ensure the safety of workers to avoid injured.