Modeling of laser supported contact pattern analysis

• Applicant: Professor Dr.-Ing. Gert Goch
• Subject Area: Measurement Systems
• Term: from 2013 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 231616586

Gears form a key-component in drive technologies and, by this, in domestic industries. An important quality feature of gear drives is the contact pattern, which describes the form and location of contact areas occurring at the meshing gear pair. Even today it is measured by the colour paste method, which is time consuming and difficult to automatise. In order to overcome this deficit, a laser based approach will be examined. It starts with the laser heating of a gear tooth and the subsequent heat transfer to a contacting tooth. The involved tooth flanks will heat up and cool down respectively during the contact, and their contact pattern can be recorded by infrared cameras. Compared to former thermographic investigations of tooth contact patterns carried out in the 80s and 90s, a significantly improved signal-to-noise ratio is expected, leading to an inspection method suitable for industrial purposes. The objective of the research project is to examine and to evaluate the feasibility of the new method theoretically. For this, the measurement process is divided into several steps which are analysed successively (heat generation and -diffusion until the moment of teeth contact, heat transfer to the second involved tooth flank, heat diffusion after the teeth contact, infrared imaging of the resulting teeth temperature distributions). The calculation of the temperature distribution will be performed using the Finite Elements Method. Finally, the temperature detection will be simulated, considering the noise characteristics of infrared cameras. The heat diffusion after the teeth contact will cause more or less blurred infrared images of the contact patterns. Hence, the original contact patterns have to be reconstructed from simulated measurements. This will be realised using neural network tools. The project results will form a planning basis aiming at an experimental verification of the new inspection method.

• DFG Programme: Research Grants