Condition monitoring of a linear rail and carriage system through vibration analysis

Sammanfattning: Condition-based maintenance is a highly relevant topic as its implementation can save both components and man-hours. Downtime is often expensive in industrial environments because machines are expensive investments; often, the machines are also part of a larger production line where it is of great importance that no bottlenecks occur. Replacing components for preventive purposes often means a waste of resources, as components are replaced based on time intervals instead of their actual functionality. Condition monitoring of the state of a machine allows components to be replaced when they start to show signs of wear and tear; it can also increase the safety of those using it, as worn parts can be replaced before they fail catastrophically. Much research has been done in the field of condition monitoring; however, the linear rail system is an elementary component that has largely been overlooked. This thesis will cover the topic of condition monitoring a linear rail system by measuring vibrations using an accelerometer. The research is done through a case study where three fault modes are tested, a broken bearing ball, alocalized fault on the rail and a skewed installation. The faults are assessed in both the frequency domain and time domain. The results are then compared to a base case, which is a clean install ofthe test track. Each fault is introduced individually, and the track is reset to the base case between each test. To pinpoint where a fault is, time domain data has been transformed into the positional domain, where the vibrational intensity is mapped to the current position of the linear rail carriage.Two out of three fault modes proved possible to identify through these methods. The positional domain plots gave more decisive results than the frequency analysis and made it possible to pinpoint the position of a localized fault.