Embedded System for Monitoring Impact Magnitude during Orange Transport

Abstract

This paper shows the use of a new system (hardware, firmware and software) to assess the negative impact of transportation on postharvest fruit quality. Fruit and vegetable postharvest losses are very high, using this system it is possible to diagnose and implement improvements in transport, thus decreasing mechanical impact. The system has a hardware endowed with a tri-axial accelerometer and a global positioning system (GPS). The firmware of the system is composed of a threshold based detection algorithm that measures acceleration peaks during transport. The system software allows reporting impact magnitude, geographic location and time of the event on a map using a virtual instrument developed in LabVIEW ™ platform. The main goal of this research was to test this equipment in the transportation of oranges and analyze the number of occurrences when exceeding a determined acceleration threshold. Orange boxes of about 23 kg each were set on a small truck, filling the body and the equipment was positioned evenly in the back and middle. The test was done through repetition and comparison of data taking into account the position of the equipment in the truck body (back and middle) and different types of pavements on a chosen path of 20.5 km divided among unpaved, asphalt and urban avenues – with and without speed bumps and roundabouts. The chi-square test at 5 % was used for the quantitative data analysis. The results show the frequency of repetition of acceleration peaks according to their orientation (X, Y, Z axes and their combinations). For the total route, a difference was observed between the frequencies of threshold violations depending on the location of the boxes. For the chosen route, the unpaved road and urban avenues showed the highest threshold violation for vertical position- axis Z. Box position in the truck and variations in pavement causes a distinctive impact magnitude. The map showing all impact data showed to be an important tool to give support to food traceability, recording critical points and situations that can be changed.