The use of WORM optical disks in ocean systems

The need for large amounts of nonvolatile storage has led the Marine Systems Engineering Laboratory to consider the use of WORM (write-once-read-many) optical disks for data and program storage. Although optical disks can store huge amounts of data, being a write-once medium presents some file-management problems. A system design which includes a file-system, hardware interface and performance measures is presented. A unique feature of the file management system allows multiple asynchronous files to be written. In addition, single files are handled efficiently by utilizing the large buffer and high transfer rate of the disk controller. The disk is interfaced to the development system running Unix as well as the run-time system running PSOS, a commercial real-time operating system. This scheme is used on EAVE, an underwater autonomous vehicle, and can be applied to data collection by the ocean community