Advanced Machine Controller Retrofit with Acoustic Emission Feedback
Abstract
Current advanced milling uses Computer Numerical Control (CNC) to make complex shapes. The milling process uses a high speed rotating tool to remove material from a larger block until the desired workpiece shape remains. These shapes are frequently created by Computer Aided Design (CAD) and translated into a tool path by Computer Aided Machining (CAM). This tool path defines the mill commands used to move the end mill to create the part. Since CNC technology today uses hardwired equipment, the mill command structure cannot be updated or modified without removing the controller. A possible solution is the implementation of the Personal Computer (PC) on the shop floor. PC's utilized as controllers for milling machine have been developed over the late 1980's and 1990's. A PC can easily handle the computing tasks of mill control, while also having the flexibility of being upgradable in implementing that control. New control codes or algorithms can be implemented by using new software, without the prohibitive cost of changing expensive control equipment. In this project, an Acoustic Emission (AE) sensor returned strain information to the PC. This strain information, which is referenced to material removal, and material removal rate, is indicated by a Root-Mean-Square (RMS) of the AE signal. From the RMS level, the PC adjusted feedrate accordingly. By controlling the feedrate, the PC can speed up or slow down the end mill trajectory. This process decreases overall milling time and/or improves surface quality by adjusting to the changing parameters during the milling process.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1997
- Accession Number
- ADA414377
Entities
People
- Roland R. Tink
Organizations
- United States Naval Academy