Design and construction of a Special Head for collecting raisins and investigating the physical damage to the product during collection

Iran is one of the world's largest and most important raisin-producing countries. Considering the amount and value of raisin exports in Iran, mechanizing this product's collection and maintaining its mechanical quality is one of the most necessary tasks in this field. Therefore, the main purpose of this study is to design and construct a collection head in a Rover for collecting raisin products from the ground and then evaluate the mechanical damage of raisin crops during collection from the ground by the collecting head. After performing the software design, the necessary calculations were performed to select different device parts. The rover was evaluated on raisins spread on the ground at three forward speeds of the rover (1, 2 and 3 km/h) and three heights of the head (2, 5 and 10 mm) from the ground surface. The constructed head with a length of 80 cm was mounted on a rover with dimensions of approximately 70 × 50 cm. The working capacity of this machine at the rotational speed of 25 rpm of the collecting brush is equal to 3.3 kg/min, and it is able to fill the 80 kg container every 15 minutes. The evaluation results showed that the effect of forward speed and head height on mechanical damage was significant (p <0.01), but their interaction was not significant. Also, the lowest mechanical damage (11%) was related to the height of 2 mm from the ground. Mechanical damage of the product was reduced by 8% at the forward speed of 1 km/h compared to the other two speeds.