In the past 20 years, machine vision (Fan Phone Number List et al. 2020; Bennedsen et al. 2005), near-infrared spectroscopy (Guo et al. 2021; Zhang et al. 2013), thermal imaging (Kim et al. 2014; Baranowski et al. 2012), structured light (Li et al. 2018; Lu Phone Number List and Lu 2017), and hyperspectral imaging detection (Munera et al. 2021; Tan Phone Number List et al. 2018) are widely used to detect the bruise of fruits. Among these techniques, since hyperspectral imaging technology is based on very much narrow-band image .
Data technology, and it combines imaging technology and spectral technology to detect two-dimensional geometric space and one-dimensional Phone Number List spectral information of the target, and the continuous and narrow band image data of hyperspectral resolution is obtained, which makes it a hot technology for detecting fruit collision. For Phone Number List example, Luo et al. (2019) used hyperspectral imaging to obtain images of sound samples and bruised samples of green-skinned, intermediate-colored-skinned (green–red), and red-skinned (dark-red) apples. The images in the visible near infrared (Vis–NIR), visible (Vis) and near Phone Number List infrared (NIR) spectral regions were subjected to principal component analysis (PCA), and then three key wavelength images were obtained for subsequent analysis based on the Phone Number List weighting coefficients of the .
PC images. Finally, the improved watershed Phone Number List algorithm was used for collision detection, and the overall accuracy was 99.5%. Zhang et al. (2022) proposed a method for predicting mechanical parameters after impact damage to apples Phone Number List based on 900–1700 nm hyperspectral imaging. Firstly, the spectra were extracted Phone Number List based on the selected regions. Then, principal component analysis (PCA) and successive projections algorithm (SPA) were used to select the feature wavelengths.