Vibroacoustic comfort in crawler compact loaders

The analysis of the noise and vibration conditions at the driving position of crawler machines is of great importance for the assessment of the risk conditions the operators of these machines are subject to. The case of crawler compact loaders, in particular, has become a pressing challenge due to the fact that these machines are greatly versatile and then widely used both in urban areas for residential constructions and in the road maintenance and mining works. This paper presents the results of noise and vibration investigations carried out on three crawler compact loaders of similar mechanical power but different brand while these machines were moving on asphalt and standardized track paths under the same conditions. Vibration signals transmitted to the operator were acquired on the seat and on the control lever of the machine in accordance with the procedures described in ISO 2631 1 and ISO 5349 1. Noise signals were also acquired at the same time as the vibration ones at the operator's ear following the procedure reported in ISO 11201. The acoustic comfort conditions were analyzed following the requirements specified in the directive 2003/10/EC; the vibration exposition values were evaluated in accordance with the above ISO standards and the provisions of Directive 2002/44/EC.