3600. Autonomous Mass Properties Tracking Database Attributes

Paper

Abstract

Gulfstream has made some interesting discoveries while deploying our autonomous mass properties tracking database. Design attributes long used in manually updated databases are not always conducive to the design of an autonomous self-updating database. This technical paper intends to explore some of the more enlightening challenges and elegant solutions discovered while making our transition to an autonomous database.
Many obstacles to the development of an autonomous database have been cited. When does the weight of a part get verified if there is no engineer calculating the weight? Even if a part’s weight is 100% perfect; that does not stop the 100% error from just one missing or extra quantity of it in the database. How do we verify the drawing tree is complete when there is no engineer inputting it? Will the computer make up drawing numbers for multiple use assemblies? How will we input delta actual weights when some program might come along behind us and mess them up? Design groups don’t use the five RP$#$8 material codes; so how does an RP$#$8 report get generated from an autonomous database? Can a computer input the half-dozen other codes we also need to generate reports? Will someone have to re-write our programs every time CATIA releases a new version? We track airplanes designed long before V5 or electronic drawing release and all our airplane data, old and new, need to be viewed together. So tell me, just how is some database going to do all that for us, and make me confident in the answers?
Gulfstream has faced and overcome these and many more challenges in the pursuit of an autonomous self-updating database. The tradition of storing the weight of a part was abandoned in favor of storing the bill of materials it is calculated from. Our database sums a part weight like an assembly weight. The exception is it totals materials and finishes instead of parts and sub-assemblies. Like back in school – the database shows its work. This simple design allows the database to record how much of the real materials and finishes, found in the drawing release system, build the weight. It does not pick from a list of made-up codes. Volumes, areas and lengths come from a database where they are stored for certification purposes by design groups. This is done in the drawing review and release processes. CATIA is not touched by Mass Properties software to calculate the weight of a part; so new releases do not affect our weight calculations. Drawing release materials and finishes are built from the five RP$#$8 materials. So densities are recorded in the database and RP$#$8 reports can be run from the database. This allows a simple database design where installations, assemblies, parts, materials, finishes and RP$#$8 materials are all stored together. Those many types of components, stored in a single component table, build up to total airplanes in a single bill of materials table. This is accomplished by coupling the Quantity field with a Unit of Measure field. The Unit of Measure contains units like ‘Each’, ‘IN^3’, ‘IN^2’ and ‘IN’. Only five components are to have the unit of measure called ‘Pound’ – the five RP$#$8 materials – and they are the very bottom callout in every branch of every bill of materials. It was also discovered that all the codes used to report mass properties can be derived from a matrix of just two available attributes. Gulfstream hopes you find the advances we are making as exciting to you as they are to us when you read and study this technical paper.