Analytical Model for Plastic Impact of Fruit on Thin Plate

Impact cushioning for bruise reduction in fresh fruit packing lines is a crucial problem when parts of the colliding materials are abrasive and rapidly wear out customary cushioning materials. A technique utilizing a thin, abrasion-resistant steel plate, for reducing the impact-related internal tissue rupture, was investigated. To quantify the amount of bruise volume and to facilitate the design of a low-damage impact surface, an upper-bound analytical model was constructed. The bruise volume was predicted as a function of the impact energy. Relatively high drop heights and non-abrasive fruits such as apples were chosen to ease the bruise volume measurements. Experimental results are presented for ‘Golden Delicious’ and ‘Granny Smith’ apples that validate the analytical model. For 0.7 mm steel plate and drop height less than 0.3 m, no bruise was detected in the apples.