Spatially Registered Infrared Imaging for Metrological Thermography

摘要

Thermal imaging systems are used in a variety of applications in the fields of quality control and test. While many of these applications - e.g. the final check of a windscreen heating system in the production line of a car - operate autonomously under repeatable conditions, some applications still require the permanent presence of an expert in order to properly setup and perform the measurement task. Common problems encountered in thermography are the proper assignment of radiation properties to individual surface patches and the mis-interpretation of temperature profiles obtained from tilted non-Lambertian surfaces. This work reports about the development of a sensor system that geometrically fuses vision and infrared sensors. Through the established spatial registration of the infrared sensor with respect to the target object we are able to perform different tasks in metrological thermography. The sensor system is used to measure temperatures at exaclty defined positions on the surface as well as emissivity coefficients. We present the sensor layout, its associated calibration strategy, and experimental results.