Precise Measurement Technology Based on New Block-Type and Rotary Shaft Balances

Abstract

Based on several decades of experience in designing and manufacturing strain gauge balances, a new block-type balance family called 7xx was developed with substantial higher stiffness and increased specific load capacities than achieved before. The compact design favours its use within models with limited space or in dynamic environments (shaker testing) where low deformations are required. Extensive tests during the development phase, static load calibrations of complete balances, and the successful usage in numerous test campaigns in different wind tunnels have confirmed the advantages to this new balance design. RUAG, in close cooperation with its partners, plays a major role in the development and testing of new counter rotating propeller technology for aircrafts. This technology and the space limitations within the nacelle necessitate new measurement technology and substantially higher power than possible with existing propulsion systems. Based on its available know-how RUAG pushed the hydraulic propulsion technology to a new level, especially with regard to specific power output and reliability. Moreover, compact rotating shaft balances for powered tests provide 6 components with good accuracy and high repeatability. Signals from the balances and the blades are transmitted by wireless telemetry systems. In-house developed software for acquiring, processing, and displaying data on- and offline has been adapted to the new systems and customers’ needs.