The problem is no less daunting for the machine. Adding to the already complex matrix of rivet data and locations is the control of every pogo and bridge move for any given panel assembly. With nine pogos per bridge, each with radial and circumferential locations, and five bridges per car, each of which must move along the length of the shuttle for tool clearance, the machine presents a monumental programming task. There really isn't any good way to test programs on the machine using the expensive panels themselves. Then, they program fastener type, approach and retract motions, and tool selection for every hole to be drilled and each rivet to be inserted.
Macros eliminate some repetitive tasks.
Working with a single CAD layer of like fasteners, for example, programmers call up an offline processing system to interrogate the fastener attri-butes file, which then determines what machine function codes to write in the program. Programming a typical assembly of two or three panels takes about 300 hours. Simulations, because of their massive file sizes, run for approximately 16 hours. This effort continues today. Some panel assemblies, such as those that make up the fuselage ends, are too complex to be riveted automatically.