Abstract
Physical damage can be considered one of the main causes of postharvest losses for fruits and vegetables. One of the challenges is to measure the impact magnitude on packing lines. There is a number of equipment that can be applied, and the most common are instrumented spheres. A Wireless Instrumented Sphere (WIS) was developed being a low cost alternative that acquires and transmits, in real time, three axis acceleration measurements from a packing line. The WIS was tested on three apple commercial packinghouses located in the south of Brazil, and in an commercial orange packinghouse, located in interior of São Paulo state, Brazil. The WIS was submitted to all those packing lines with fruits at regular speed from the fruit reception to the packaging step. For each packing line at least four repetitions were conducted, and three levels of acceleration were considered: >10 G, > 20 G, and above 30 G. In parallel, a laboratory trial was conducted with the WIS and a commercial instrumented sphere, Instrumented Recorded Device – IRD (Techmark, Inc., Lansing, USA). The instrumented spheres were subjected to drop fall, using a dedicated equipment, from three known distances (20, 30 and 40 cm) to solid steel and two different padded surfaces, such as: polyurethane foam and courvin at a foam thickness 8 mm. The data for the three apple packinghouse showed different results as number of impacts at the three different thresholds (>10 G, > 20 G and > 30 G) and the maximum peak acceleration found. The orange packing line showed higher acceleration range peaks than the apple packinghouses. For the laboratory trial it was possible to detect different impact magnitudes among distinctive highs and surfaces. This new Wireless Instrument Sphere (WIS) showed to be an important device for measuring impact magnitude in fruit packing lines.
