Design and implementation of low-cost miniature crop spectral reflectance meter based on smart mobile devices
In order to achieve low-cost,real-time and non-destructive monitoring of crop growth information,based on spectral analysis technology,this study selected two bands,395 nm and 800 nm,and carried out the re-search and development of a low-power miniature crop spectral reflectance measuring instrument based on a smart mobile device according to the principle of the optical sys-tem and miniaturisation requirements,including the package housing,optical system and hardware circuit design and con-trol system App development.Measurements of the four channels(395 nm and 800 nm sunlight receiving channels and crop reflected light receiving channels)of the meter were calibrated using an integrating sphere and a spectrometer(ASD),and the accuracy of the meter was checked using four grey scale panels with standard reflectance(20%,40%,60%,100%).The results showed that the coefficients of determination of the calibration equations of the four channels were above 0.998 0,the root mean square errors of 395 nm and 800 nm reflectance were 1.46%and 1.07%,and the average absolute errors were 1.17%and 0.82%,respectively.The relative errors of the reflectance measured by the four standard reflectance greyscale panels in the 395 nm and 800 nm bands were less than 2.0%and 3.6%,respectively,and the coefficients of vari-ation were in the ranges of 1.36%-4.17%and 0.78%-2.36%,respectively.With a volume of 32 cm3 and a weight of only 20 g,the instrument is low-cost,high-precision,easy-to-operate,and scalable,which can realize real-time crop growth monitoring based on smart mobile devices.
NETL
NSTL
万方数据
维普
