Studies On Mechanical Properties Of Orange In Response To Robotic Harvesting And Quality Changes During Storage

With the development of computer technology,intelligent robot has been widely in many fields of application,oranger harvesting robot has beening researched at home and abroad,however,due to the special structure of the organization of oranger, it's easy damaged by machine hand when picking,so,research on the basic mechanical property of oranger,not only can to providing theoretical basis for the design of robots can also for transportion,storage and processing.Study mechanical property of orange on different directions(the axes and the radial) and different parts(cross section and longitudinal sectioan) by burst test and punture test,showed that the mechanical property of different directions is not marked, the average resistance of press is 105N,correlation coefficient is lower between Compression resistance and diameter,weight,and Pericarp thickness of oranger;the mechanical property of cross sectioan is not marked,the mechanical property of longitudinal sectioan is marked,the bottom have the worst ability to resist to destroy, therefore,we must avoid the paw to touch the bottom;the mechanical property is marked between orangers.Statistical analysis the compression resistance and the puncture force(which test condition is probe is P2 and rate is 2mm/s) on orange,the effect of test conditions on mechanical property.Because of the mechanical property is marked between orangers, the size of samples is wide.Showed that when the pressure is less than 70N,no sample is rupture,90 percent is rupture between 80N and 90N;no sample is damaged when puncture force is less than 3N,most of sample is between 4N and 8N;test rate (2mm/s,4mm/s,6mm/s,8mm/s,10mm/s) doesn't has significantly impact on burst fore, puncture force,burst distance and puncture distance;puncture diameter has marked impact on puncture test,puncture force and puncture distance increases with the diameter.Research on mechanical property of peel and pulp by burst test,punture test. Showed that the puncture force of upper,central and lower peel has no significant differences,range 5N to 6N;the sheer stress is not significant differences on different directions;the sheer stress of external peel is bigger than the internal,the average sheer stress of upper,central and lower external peel is 2794Pa,2778Pa and 2431Pa, the internal is 2073Pa,1981Pa and 1607Pa;the puncture force of pulp is smaller, about 1N;in tension test on joints between orange and branch,peel is easily damaged, to avoid damage,the tension force can not beyond 17.5N.Research on trends of the mechanical property of orange at different maturity stages and variety by burst test and puncture test.Showed that with the maturity of orange,burst force and puncture force is decreased,early rapid decline,the late slow; the mechanical property of orange is not obvious difference which origin is zhejiang, shanghai and zhenjiang,three species can refer to zhengjiang orange when design picking robot,the compress force and puncture force of oranges is the biggest,the sweet orange is the smallest.Research on quality changes on three conditions,which is room temperature, natural state and frozen storage,showed that rate of weight loss is increase with storage time;content of Vc is decline;content of soluble is increase at pre-storage, and then decline;the changes of mechanical property is complex,puncture force is increase at first,and then decline which storage condition are room temperature and natural state,previous 30 days,it changes little at frozen storage,then gradually increasing.