How a Pseudo-Pressure Sensor Improves Diagnostics in a Solenoid Actuated Valve

The Coca-Cola Freestyle dispenser uses a solenoid actuated valve for dispensing water. There is no pressure sensor on the water line, and it is difficult to distinguish between an upstream pressure loss issue and inherent valve failure. This results in the unnecessary replacement of good valves in dispensers in the field. In this talk, hear about the development of a novel pseudo-pressure sensor that estimates the line pressure based on the solenoid valve current signature. MATLAB^® was used to analyze the current signature test data, extract features, and develop a regression model to predict line pressure. This model was then deployed to a memory-constrained ARM Cortex-M microprocessor using Simulink^® for testing and deployment to production. This pseudo-pressure sensor feature has improved dispenser diagnostics and reduced valve replacements, leading to a significant drop in field service cost. In addition, learn about future work plans to develop diagnostics around valve blockages using MATLAB and Simulink for machine learning and deployment.