Development and Testing of a Cam Disc Comb-Type Picking Machine for Chrysanthemum (Dendranthema morifolium Ramat. Tzvelev)

Abstract

HighlightsA practical cam disc comb-type chrysanthemum picking machine was developed.A three-dimensional model of the picking machine was designed in SolidWorks.The working principle and motion trajectory of the picking comb teeth were analyzed.The best working parameters of the picking machine were obtained with field tests.Abstract. Aiming at the problems of labor, picking efficiency, and mechanization, a small practical cam disc comb-type chrysanthemum picking machine was designed. The picking machine, mainly composed of a wheeled frame, power transmission system, cam disc, picking comb, and cleaning comb sleeve, uses the pulling force of comb teeth to pick chrysanthemum flowers. The comb teeth rotate on a central shaft, and their swing angle is determined by a groove on the cam disc. One rotation of the comb teeth completes the process of picking, lifting, and unloading. In this study, the parameters of the cam profile were designed using an analytical method. To ensure reliability of the components, the trajectory of the comb teeth and their structure and motion parameters were analyzed, and the conditions for picking chrysanthemums were determined. The physical parameters of chrysanthemum plants were measured, and a prototype picking machine was built. Field tests were conducted using the comb rotational speed, comb teeth spacing, and comb working depth as the test factors and the picking rate, impurity rate, breakage rate, and drop rate as the evaluation indexes. The effects of each factor and the interaction of any two factors on the picking effectiveness were obtained. The test results suggested that the most effective harvesting was achieved when the comb rotational speed was 40 rpm, the comb teeth spacing was 8 mm, and the comb working depth was 200 mm. With these parameters, the picking rate was 93.28%, the breakage rate was 1.21%, the impurity rate was 8.38%, and the drop rate was 6.61%. The prototype machine achieved good picking effectiveness, and this study provides a technical foundation for the realization of mechanized chrysanthemum harvesting. Keywords: Cam, Chrysanthemum, Comb teeth, Motion track, Picking machine.