Multivariate sensing and wireless data communication for process monitoring in RF-shielded environment

Online process metrology is critical to ensuring manufacturing quality and productivity. This paper presents the design and modelling of a multivariate sensor that enables the simultaneous measurement of multiple parameters from within an RF shielded environment, e.g. an injection mold. A coded wave modulation scheme is developed for wirelessly transmitting the parameters through the mold. The design of the modulator is optimized through a coupled field analysis for noise reduction. The effectiveness of the sensing method is demonstrated in the online measurement of melt pressure, temperature, viscosity, and velocity. This sensing method is applicable to various process monitoring scenarios. (C) 2012 CIRP.