Reduction of Whole-Body Vibration transmitted to test drivers performing complete vehicle durability testing at Hällered Proving Ground

Abstract

The Vehicle Durability Division at Volvo Car Group is performing complete vehicle testing at Hällered Proving Ground. The purpose is to verify the durability compliance of the car according to the Durability Vehicle Life Trustmark. However, the rough road conditions at Hällered Proving Ground results in test drivers being exposed to Whole-body vibration. It has been proven that prolonged Whole-body vibration exposure may lead to muscle fatigue and weakening of the lumbar musculature, resulting in decreased spinal support and lower back pain. As a result, Swedish Work Environment Authority introduced directives according to AFS 2005:15, aimed to protect the employee from injuries due to vibration at work. These directives are based on the original regulations found in 2002/44/EC. Hence, this thesis work has aimed to reduce Whole-body vibration transmitted to the test drivers as an effect of performing complete vehicle testing at Hällered Proving Ground. A solution has been carried out based on material tests performed in a hexapod and transmissibility rig. Evident results confirm that there is a dependency between increased PUR foam thickness and extended drive time, before the daily exposure values are reached. Increased foam thickness appears to reduce the frequency at which resonance occurs, but yields higher transmissibility at amplification.