Computational imaging for drill bit wear estimation

Aerospace and automotive industries make more and more use of carbon fiber laminates. They offer high advantages in terms of mechanical performance but are difficult to work on and need precise and expensive tools. Drilling is the most common operation; drill bits must be accurately verified before use to avoid damages during the process. This paper proposes an optical inspection system for drill bits wearing estimation based on a custom-designed illumination device and a processing algorithm based on computational imaging. The elaboration of the computational image is used to measure the drill bit cutting profile. Drill bits have been worn on carbon fiber laminates, and a tool wear model has been extracted using the proposed system. The proposed method has been tested on both used and new drill bits, used in the aerospace industry.