High resolution simultaneous dual liquid level measurement system with CMOS camera and FPGA hardware processor

For MD process it is necessary a very high precision system to measure the solution level in the reservoirs, able to detect changes smaller than 0.05 mm. This is due to the small fluxes through the membrane, and therefore it is necessary to detect the small changes produced in the liquid levels in the reservoirs. Until now such measurement has been made manually, by means of a cathetometer, but it resulted very uncomfortable. In order to overcome this issue, a high resolution and accuracy system (0.013 ± 0.008 mm), that makes automatic measurements of both reservoirs, cold and hot, is proposed. This system is based on a laser beam, assisted with a high resolution 3 Mpixels CMOS camera and a computer vision processor implemented in a FPGA, with a measurement rate up to 12 times per second.