The Mechanical Properties Of Tomatoes And The Application In The Paw's Design Of A Harvesting Robot

With the advance of information era, the next wave of agricultural machine will be toward automatization, intelligentization and excessive function. Thus, the researches and application of agricultural machine will see much broad prospects.Fruit and vegetable harvesting is an important process in agricultural production. To raise agricultural labor productivity and working quality, reduce working density, improve working environment and realize harvesting mechanization, automatization and intelligentization, a configuration of tomato harvesting manipulation used in greenhouse was designed based on the mature tomatoes' puncture experiment (force-distance test). The puncture experiment researched the mechanical properties of tomatoes. The thesis received failure stress and failure intensity of each group tomato.The mechanical properties of tomatoes are importance design of tomato harvesting manipulation. This thesis did some researches on tomatoes using TA-XT2i texture analyzer: doing puncture experiments often group tomatoes. Thesis received failure stress and failure intensity of each group tomato. All of these were the foundation of end-effector's design.Based on the cultivating methods and mechanical properties of tomatoes, the thesis chose a harvesting manipulation with two paws. The thesis draw a conclusion that the max of the end-effector's working degree was not independent of the pole's size, the working degree was relation with the camber of the wrist connected with the paws. At the same time, the thesis gained the relation of the drive force and the tighten force when the end-effector picked tomatoes. Thesis checked computations that the hold error of two turning paws less than 5mm. Finally the thesis gained the sizes of each pole through the geometry connection of poles. Otherwise, the thesis designed the wrist drive, illuminated how to choose the drive mode and stepping motor drives.The thesis also advanced the designing request of the manipulation arms and wrist, working out the manipulation with a five-degree-of freedom. At the same time, the thesis advanced the forward kinematics and inverse kinematics matrix of manipulation, the thesis also referenced the restriction condition of tomato harvesting manipulator and tomato physiological and cultivating methods, designed approximate size of manipulator. Then the 3D model of tomato harvesting manipulator was drawn in the Pore. All of these supplied the foundation of the manipulation's control and simulation in the farther research.