A DISCRETE TIME MANAGEMENT MODEL FOR COMPARING MECHANICAL CUCUMBER HARVESTING SYSTEMS IN MICHIGAN (PLANT MODEL)

Three mechanical once-over cucumber harvesting systems in Michigan were compared using a discrete state model. The model was constructed using parameters obtained in two separate sets of experiments. The first experiment studied and determined plant fruit dynamics as a function of time. The second experiment was concerned with the study and determination of the parameters of the harvesters. The model was simulated using a computer algorithm CUCHARV. The program included a cash flow model to determine the cost of owning and operating the harvesting system.;A field trafficability model was also established to determine the sequence of go/no-go days on a daily basis for three locations in Michigan and for three soil types. These sequences were used in the model to study the sensitivity of weather on the net harvest outcome.;The model was validated for two locations in Michigan and revealed a future promise to aid as a decision tool for farmers and processors and as an educational tool for systems analysts and researchers.;The model calculated daily net dollar returns based on the dollar value per fruit size grade diminished by the cost of harvesting on that day. The output also included the daily average per hectare and daily total per farm of fruit number and fruit weight per grade and the average and total cost of harvesting.