Design And Experimental Research On Lifting Platform In Citrus Orchard

Citrus is one of the most important fruit trees, which has the largest planting area in the hill and mountain area of south China and was also an effective way for the orchardists to obtain their wealth. With the large-scale planting in citrus orchard and the rising of labor costs, it is especially important for slashing personnel costs and enhancing productivity to develop the machinery which is fit for working in citrus orchard and can be manual assistant during picking, flower thinning and pruning processes. Therefore the research on lifting platform in citrus orchard has potential practical application value.On the basis of analyzing the mechanical structure working in all kinds of orchards, around the design of the complete machine and selection of key components of lifting platform in citrus orchard, the thesis carried out the research from the following four aspects and educed correlative design principle:(1) The mathematical model of citrus tree was established through the mapping of the tree imaging, and the dimension parameters of the lifting platform suitable for citrus orchard were obtained by discussion:the overall dimensions should be no more than1.5meters1.2meters, the lifting height can be in0.8-1.2meters and the turning radius must less than2.0meters.(2) The crawler traveling mechanism was refitted on the basis of the profiling traveling theory, and the drive efficiency was analyzed.(3) In consideration of working comfort and the stability of the complete machine, the lifting system and manned worktable were designed.(4) The fixed-point secondary leveling was proposed, and the corresponding driving and control system were designed.Grounded on the real situation of working in citrus orchard, the prototype machine of lifting platform was made based on the comprehensive analysis of the dimension parameters, running mechanism, lifting system, manned worktable and leveling device. And some experiments were carried out by simulating the working conditions to testing maximum traction, running in even speed, lifting operation and radius of turning circle. All the results show that the machine can fulfill the working requirements:the maximum lifting height and permissible gradient of which can be1.2meters and15.6degrees, the maximum traveling speed, minimum rate of descent and ascending velocity of which are1.1,0.12and0.03meters per second respectively, and which can reach a minimum turning radius of0.75meters.