Research On Number Of Key Technologies Of Kiwifruit Maturity Detector

Fruit maturity is an important index for fruit grading, freshness and storage.At present,many detection techniques have been applied to internal quality detection of fruit,such as machine vision,near infrared spectroscopy,magnetic resonance imaging and so on.But these detection methods are disappointing on one hand,such as the weaker adaptability, tedious testing process,expensive,high detection cost,large volume of detection device and so on. So it is difficult to detect in real-time and develop miniaturized instruments. Therefore, the further experimental study is very necessary.Bio-impedance is a physical quantity which can reflect the tissue,organ and cell electrical properties.Impedance character will change when the chemical composition changes within the organization.Therefore,tissue status can be tested quickly,correctly and nondestructively through bio-impedance measurement.Kiwifruits are high in nutrient and health care fuction which is known as "the king of fruits".At present,our country plays an important role in cultivation and export of kiwifruits.However, it will make kiwifruits addle and decrease of quality because of backward testing,and that has caused serious economic losses each year.So if we can discover and eliminate internal defectice kiwifruits before storage or processing, this will not only reduce the loss but also improve the quality of storage;During circulation and sales,if we can achieve strict quality grading, this will not only protect interests of consumers, but also improve the processing quality and export level of kiwifruits.Developing, production kiwifruit maturity detector that is lower price,small size,useful has been extremely urgent.This will be important way which the fruit industry drives economic development.This project,used kiwifruit produced in Weinan, Shanxi as samples,kiwifruit testing is the main purpose.Research status of current fruit maturity testing methods were pointed out according to analysis result.A new kiwifruit maturity testing method based on bio-impedance was proposed.In this study,Kiwifruit was taken as research object,the relationship between its impedance and freshness was studied on the self-made visual instrument LABVIEW kiwifruit impedance testing platform;The influences of testing position,drive frequency,perturbation amplitude and home-made electrode system were affirmed through experiment;Kiwifruit maturity indexes based on impedance were set up,at the same time, verified the feasibility of the evaluation index by experiments.According to these indexes,a kiwifruit maturity testing system by S51and some relevant components was build up and verified this testing system by conducting experiments.Through validation, the testing system can achieve the requirements of practical application and the detecting accuracy can reach80%,and kiwifruit maturity recognition model based on BP neural network theory was set up also and the recognition rate can reach90%,so the trained network can be used in practical application.