Apple handling impact data acquisition and analysis with an instrumented sphere

Abstract

Agricultural perishables have traditionally been handled in bulk, or in an assortment of packing arrangements in an attempt to get the product to the consumer in an acceptable condition. A new data-acquisition system, an instrumented sphere, developed to measure and record impacts was used in preliminary studies in 1987 to evaluate the impacts sustained in apple packing lines. A brief transport study was also conducted. The instrumented sphere is 89 mm in diameter, has a mass of 0·312 kg, and consists of a circuit board and components cast in beeswax for structural solidity. The instrumented sphere is a stand-alone computer and operates for several hours unattended. It collects and stores acceleration magnitudes above an adjustable pre-programmed threshold, each referenced to an internal clock. Data collected after each test can be processed for information on impact magnitude and time of occurrence. These preliminary studies suggest that the sphere is a useful tool for identifying areas in packing lines and transport where bruising occurs. For example, a simple modification to a bagging conveyor resulted in a 75% reduction in impact magnitude. While the instrumented sphere does not exactly represent any particular apple variety it gives an excellent indication of what apples experience as they go through the handling processes from orchard to consumer.