Search Results

Nowadays, optimization of manufacturing and assembly operations requires taking into account the inherent processes variations. Geometric and dimensional metrology of mechanical parts is very crucial for the aerospace industry and contributes greatly to its. In a free-state condition, non-rigid parts (or compliant parts) may have a significant different shape than their nominal geometry (CAD model) due to gravity loads and residual stress. Typically, the quality control of such parts requires a special approach where expensive and specialized fixtures are needed to constrain dedicated and follow the component during the inspection. Inspecting these parts without jig will have significant economic impacts for aerospace industries, reducing delays and the cost of product quality inspection. The Iterative Displacement Inspection (IDI) algorithm has been developed to deal with this problem.

Aerospace panels are commonly restrained on complex inspection fixture jigs during the measurement process. Forces used to restrain the part are also monitored because of the part functional requirements. Given the difficulties in measuring these types of parts, this paper reviews the available fixtureless inspection methods with a focus on the challenges of their implementation and their aptitude to be used to estimate the part profile and the necessary restraining forces of an aerospace panel. To perform this investigation, finite element analysis is used to predict the constrained shape of four (4) simulated free state aerospace panel, with two different type of boundary condition, in five scenarios. From those analyses, the importance and limits of current finite element boundary setting method embedded in fixtureless inspection methods for nonrigid parts are highlighted.