New radar system for industrial measurements achieves one-micron accuracy



Click image to enalarge: The radar system in the measurement chamber.

Scientists of KIT (Karlsruhe Institute of Technology) and RUB (Ruhr-Universität Bochum) with the help of a new radar system, have achieved an accuracy of one micron in joint measurements. The system is characterised by high precision and low cost with applications in production and plant technology. Frequently, glass scales, inductive sensors, or laser measurement systems are used for distance measurements. Glass scales are very precise and reach micron precision, but are inflexible and too expensive for daily use. Inductive sensors measure distances with a coil, magnetic field, and the movement works in a contact-free manner without wear, but are limited in repetition rates. Lasers allow for a highly precise measurement, but are unsuited to dust, humidity, or strongly changing light conditions. Radar signals, by contrast, can penetrate dust and fog quite well and have, so far, found applications mainly in weather observation, air monitoring, and vehicle-distance measurements. ??Scientists at KIT's IHE (Institut für Hochfrequenztechnik und Elektronik), under Prof Thomas Zwick and under Prof. Nils Pohl—Chair for Integrated Systems at RUB—have now developed and successfully applied a radar system for distance measurements. The system is characteried by a previously unattained precision of 1 ?m. For the measurement, the scientists use a FMCW (frequency-modulated continuous wave), the emitter of which operates continuously during measurement. The RUB researchers developed the hardware, KIT scientists the necessary algorithm. The radar system measures distances of up to several meters in free space with micron accuracy. Compared to laser systems, this measurement apparatus is not only cheaper, but can also measure absolute positions. ??The radar system is now being optimised in several research projects. Its accuracy will be further improved. In the future, it will be used to make measurements in production and plant technology with high precision, in a flexible manner, and at low costs. KIT (Karlsruhe Institute of Technology) RUB (Ruhr-Universität Bochum)