A novel system for measuring damaging impacts on table olives

The consumer today demands high quality products; fruit with defects or in poor condition generate dissatisfaction and a consequent reduction in consumption. In recent years, interesting systems have been used (i. e. "artificial fruit") in order to identify the cause of damage during mechanical harvesting and/or post-harvest operations. In this paper, the authors present a new system designed to measure the impacts received by table olives in the processing stages from harvesting to packaging. The device is an instrumented sphere designed and implemented by the Agricultural Mechanics Section of the Department of Agricultural and Forest Sciences, University of Palermo, Italy. It contains a triaxial Micro Electro-Mechanical Systems (MEMS) sensor capable of acquiring acceleration from a few mg to 400 g (where g is the gravitational acceleration). It has a microcontroller with software developed for the specific application, a 16 bit A / D converter that allows a resolution of a few mg, a mini-USB port for connection to a master, which is connected to the PC via a common USB port. The master communicates with the sphere to download the data and to adjust parameters such as the data acquisition frequency, which can reach up to 1 kHz (50 Hz, 100 Hz, 400 Hz and 1 kHz). Preliminary tests performed on the functionality of the acquisition system show that the information obtained by the instrumented sphere are useful for identifying the stresses the fruits are subjected to during harvesting and post-harvest