A Cyber-Physical RPM Variometer using MQTT Protocol for Real-time Continuous Data-Acquisition

Abstract

In rotational motion, there are several physical phenomena, which exclusively exist only if the angular speed varies. Those phenomena disappear at constant angular speed in rotating objects since constant angular speed establishes a static state through its constant centrifugal force. The phe-nomena such as (a) RPM-variation induced stress-variation inside rotating blades (b) RPM-variation induced low-frequency vibration generation inside rotating elements (c) RPM-variation induced energy harvesting inside rotating objects (d) RPM-variation induced variable vortex formation can fall under the mentioned category, which requires continuous and synchronized monitoring of RPM-variation in correlation with the mentioned phenomena. Firstly, commercially available typical RPM meters, which provide discrete angular speed measurements do not satisfy this requirement. Secondly, to capture the dynamical behavior, those phenomena require real-time, continuous and synchronized RPM-variation monitoring preferably through a cyber-physical connectivity for the emerging loT systems. Therefore, this paper presents the design and implementation of a cyber-physical RPM variometer featuring real-time, continuous, synchronized data-acquisition using MQTT protocol. The dashboard-GUI of the measurement system displays the RPM-tracing in the local-terminal, as well as, in the remote-terminal. The interface provides a configurable and interactive platform for real-time RPM variation measurement with the facility of measurement-parameter customization. The measurement system operates within a range of 1 to 15000 RPM with a minimum accuracy of 99.5 % for a rated scanning time of 2 sec, which is customizable. The developed non-contact type measurement system provides the facility of integrability with several IoT-enabled hardware peripherals.