QDec-M-Line: A Geometric Quality Control System to Assess Fully Assembled Parabolic Trough Modules in Series Production

A new inline measurement system for automatic quality assurance of the concentrator shape of parabolic trough modules in series production has been developed. The applied deflectometry measurement technique is based on the iterative reflection of an illuminated movable pattern in the mirror surface and its distortion due to mirror surface deviations. The movable pattern can be realized conveniently by making use of a gantry crane typically utilized in parabolic trough module production workshops. The measurement system was built and extensively tested on laboratory scale. All relevant effects on the slope measurement accuracy, reliability and dependency on harsh ambient conditions were thoroughly analyzed. All required features for the upscaling to full parabolic trough module size and for flexible adaption to different geometries are available. The here presented progress in the development of the system and the results of the validation measurements demonstrate its readiness for an industrial scale implementation.