Quantification of 6-degree-of-freedom chassis whole-body vibration in mobile heavy vehicles used in the steel making industry

Whole-body vibration (WBV) of mobile machines used in the steel making industry has not previously been quantified in six-degrees-of-freedom (6DOF). The purpose of this paper was to quantify 6DOF vibrations during the daily operating tasks of 5 commonly used mobile machines types used in the steel making and metal smelting industries. Vibration data were recorded from the chassis of five commonly used mobile machines using a MEMSense MAG3 triaxial accelerometer & gyroscope (MEMSense, SD, USA), and analyzed using custom MatlabTM code. Elevated values were observed at the chassis for crest factors, peak running root mean squared accelerations, and vibration total values, resulting in ISO 2631-1 (1997) comfort predictions ranging from Uncomfortable to Extremely Uncomfortable. Vibration dominant frequencies were generally between 1 and 8Hz. A second peak which occurred at approximately 27 Hz was observed for each vehicle in almost all axes. Occurring at a frequency that has the potential to produce negative health effects, this second peak was probably caused by the engine idling or running at low speeds. Field vibration profiles from this study have been used as inputs to a 6DOF robot for use in a corresponding laboratory study designed to optimize seat selection thus allowing the steel making and other similar industries to select operator seats based on industry specific field vibration characteristics.