Vibration level generated by a rotary pick-up for the harvest of table olives

The purpose of this study was to measure the level of vibration transmitted to the operator's hand while using electric machine used in the harvest of table olives. The tests were conducted measuring the level of vibration generated by three dierent types of plastic coating material, such as natural rubber, silicon and vulcanized rubber, used as coating of the teeth in order to minimize the damage to the drupes. The teeth coated were tested at three dierent rotation speed: 2000, 3000 and 4000 rev/min. The rotation speed of the teeth was controlled through the use of a mechanical revolution counter with a measuring range of the number of revolution between 400 and 50.000 rev/min and three dierent protection coatings, with a thickness of 7, 14 and 19 mm were tested. The data of all tests were statistically analyzed, by the simple analysis of variance. The hand-arm vibration from the dierent rake models tested depend mainly from kinematics of the rake used, varying in the dierent trials from a minimum of 6.3 m/s2 to a maximum of 22.4 m/s2. Probably this aspect is the main element to be taken into account by the ergonomic point of view.