Development of a Multi Camera System for Flap Gap Observation in Flight Test

Abstract

A dedicated multi camera system was developed by DLR with the objective of flap gap observation within the EC funded project AWIATOR of the 5th frame work programme of the European Commission. Cameras mounted in the aircraft cabin of the Airbus A340 MSN1 were focused on targets on the spoiler trailing edge and on the flap. The special flight test requirements set the conditions, which the system had to fulfill. Hence a multi camera system was set up which can operate up to 4 cameras simultaneously all controlled by one PC. The hardware and software was designed for an automatic image acquisition procedure activated by a simple remote start button, which was placed on the test engineer’s desk. In the 1st Flight Test campaign each of the 4 cameras had its own field of view, which limited the possibilities of the evaluation and analysis of gap width changes. In the 2nd Flight Test campaign the 4 cameras were used as two stereoscopic systems. The evaluation worked well in spite of the small angle between the optical axes of the stereo cameras of only 9°. The stereo set up enables the determination of the 3D position of the targets. With that information absolute distances between spoiler and flap have been measured. Additionally, the translation and rotation of the flap with respect to the spoiler due to different wing loads can be calculated easily. Also the hardware was improved for the 2nd flight test campaign by adapting the system for the usage of advanced cameras with a higher resolution and sensibility. The improvements of the hardware as well as the application of a stereo system enabled measurements of considerably improved quality.