Yang Yu

Dr. Yang Yu

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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17 June 2020 in IEEE Access
Verified
Journal Article
Open access
YYYang Yu
Yang Yu
ZKZhang Kailiang
Zhang Kailiang
HLHui Liu
Hui Liu
LYLi Yang
Li Yang
DZDongxing Zhang
Dongxing Zhang
At present, the primary technical deterrent to the use of strawberry harvesting robots is the low harvest rate, and there is a need to improve the accuracy and real-time performance of the localization algorithms to detect the picking point on the strawberry stem. The pose estimation of the fruit target (the direction of the fruit axis) can improve the accuracy of the localization algorithm. This study proposes a novel harvesting robot for the ridge-planted strawberries as well as a fruit pose estimator called rotated YOLO (R-YOLO), which significantly improves the localization precision of the picking points. First, the lightweight network Mobilenet-V1 was used to replace the convolution neural network as the backbone network for feature extraction. The simplified network structure substantially increased the operating speed. Second, the rotation angle parameter $\alpha $ was used to label the training set and set the anchors; the rotation of the bounding boxes of the target fruits was predicted using logistic regression with the rotated anchors. The test results of a set of 100 strawberry images showed that the proposed model’s average recognition rate to be 94.43% and the recall rate to be 93.46%. Eighteen frames per second (FPS) were processed on the embedded controller of the robot, demonstrating good real-time performance. Compared with several other target detection methods used for the fruit harvesting robots, the proposed model exhibited better performance in terms of real-time detection and localization accuracy of the picking points. Field test results showed that the harvesting success rate reached 84.35% in modified situations. The results of this study provide technical support for improving the target detection of the embedded controller of harvesting robots.

1 December 2023 in Agriculture
Verified
Journal Article
Open access
PDF file
HHHu Jinpeng Hu
Hu Jinpeng Hu
Lizhang XuLizhang Xu
Lizhang Xu
YYYang Yu
Yang Yu
JLJin Lu
Jin Lu
DHDianlei Han
Dianlei Han
LZLinjun Zhu
Linjun Zhu
Aimed at addressing the problems of the existing straw choppers on combine harvesters, such as a large cutting resistance and poor cutting effect, combined with bionic engineering technology and biological characteristics, a bionic model was used to extract the characteristics of the cutting blades of locusta migratoria manilensis’s upper jaw. A 3D point cloud reconstruction and machine vision methods were used to fit the polynomial curve of the blade edge using Matlab 2016. A straw-cutting process was simulated using the discrete element method, and the cutting effect of the bionic blade was verified. Cutting experiments with rice straws were conducted using a physical property tester, and the cutting resistance of straw to bionic blades and general blades was compared. On the whole, the average cutting force of the bionic blades was lower than that of the general blades. The average cutting force of the bionic blade was 18.74~38.23% lower than that of a smooth blade and 1.63~25.23% lower than that of a serrated blade. Similarly, the maximum instantaneous cutting force of the bionic blade was reduced by 2.30~2.89% compared with the general blade, which had a significant drag reduction effect. By comparing the time–force curves of different blades’ cutting processes, it was determined that the drag-reducing effect of the bionic blade lies in shortening the straw rupture time. The larger the contact area between the blade and the straw, the more uniform the cutting morphology of the straw after cutting. Field experiment results indicate that the average power consumption of a straw chopper partially installed with bionic blades was 5.48% lower than one with smooth blades, measured using a wireless torque analysis module. In this research study, the structure of the straw chopper of an existing combine harvester was improved based on the bionic principle, which reduced resistance when cutting crop straw, thus reducing the power consumption required by the straw chopper and improving the effectiveness and stability of the blades.

23 November 2024 in Agriculture
Verified
Journal Article
Open access
PDF file
YYYang Yu
Yang Yu
HXHehe Xie
Hehe Xie
ZKZhang Kailiang
Zhang Kailiang
YWYujie Wang
Yujie Wang
YLYutong Li
Yutong Li
Lizhang XuLizhang Xu
Lizhang Xu
Due to the complex unstructured environmental factors in ridge-planting strawberry cultivation, automated harvesting remains a significant challenge. This paper presents an oriented-ridge double-arm cooperative harvesting robot designed for this cultivation. The robot is equipped with a novel non-destructive harvesting end-effector and two self-developed specialized manipulators, integrated with the strawberry picking point visual perception system based on the lightweight Mask R-CNN and a CAN bus-based machine control system. The greenhouse harvesting experiments show that the robot achieved an average harvesting success rate of 49.30% in natural environments after flower and fruit thinning, while only a 30.23% success rate was achieved in untrimmed natural environments. This indicates that the agronomic practice of flower and fruit thinning can significantly simplify the automated harvesting environment and improve harvesting performance. Automated harvesting efficiency test results show that the single-arm average harvesting speed is 7 s per fruit, while double-arm cooperative harvesting can achieve 4 s per fruit. Future expansion by increasing the number of robotic arms could significantly improve harvesting efficiency. However, the study conducted for this paper was poor for those strawberries whose body or stem was severely blocked, which should be further improved upon in follow-up studies.

23 December 2024 in Foods
Verified
Journal Article
Open access
PDF file
CFChenlong Fan
Chenlong Fan
YLYing Liu
Ying Liu
Tao CuiTao Cui
Tao Cui
MQMengmeng Qiao
Mengmeng Qiao
YYYang Yu
Yang Yu
Yuping HuangYuping Huang
Yuping Huang
Rapid and accurate detection of protein content is essential for ensuring the quality of maize. Near-infrared spectroscopy (NIR) technology faces limitations due to surface effects and sample homogeneity issues when measuring the protein content of whole maize grains. Focusing on maize grain powder can significantly improve the quality of data and the accuracy of model predictions. This study aims to explore a rapid detection method for protein content in maize grain powder based on near-infrared spectroscopy. A method for determining protein content in maize grain powder was established using near-infrared (NIR) reflectance spectra in the 940–1660 nm range. Various preprocessing techniques, including Savitzky−Golay (S−G), multiplicative scatter correction (MSC), standard normal variate (SNV), and the first derivative (1D), were employed to preprocess the raw spectral data. Near-infrared spectral data from different varieties of maize grain powder were collected, and quantitative analysis of protein content was conducted using Partial Least Squares Regression (PLSR), Support Vector Machine (SVM), and Extreme Learning Machine (ELM) models. Feature wavelengths were selected to enhance model accuracy further using the Successive Projections Algorithm (SPA) and Uninformative Variable Elimination (UVE). Experimental results indicated that the PLSR model, preprocessed with 1D + MSC, yielded the best performance, achieving a root mean square error of prediction (RMSEP) of 0.3 g/kg, a correlation coefficient (Rp) of 0.93, and a residual predictive deviation (RPD) of 3. The associated methods and theoretical foundation provide a scientific basis for the quality control and processing of maize.

28 October 2025 in Agriculture
Verified
Journal Article
Open access
PDF file
YYYang Yu
Yang Yu
ZLZengyao Li
Zengyao Li
BDBuwang Dai
Buwang Dai
JPJiahui Pan
Jiahui Pan
Lizhang XuLizhang Xu
Lizhang Xu
To address the issues of signal loss and insufficient accuracy of traditional GNSS (Global Navigation Satellite System) navigation in agricultural machinery sheds and farm access road environments, this paper proposes a high-precision mapping method for such complex environments and a real-time localization system for agricultural vehicles. First, an autonomous navigation system was developed by integrating multi-sensor data from LiDAR (Light Laser Detection and Ranging), GNSS, and IMU (Inertial Measurement Unit), with functional modules for mapping, localization, planning, and control implemented within the ROS (Robot Operating System) framework. Second, an improved LeGO-LOAM algorithm is introduced for constructing maps of machinery sheds and farm access roads. The mapping accuracy is enhanced through reflectivity filtering, ground constraint optimization, and ScanContext-based loop closure detection. Finally, a localization method combining NDT (Normal Distribution Transform), IMU, and a UKF (Unscented Kalman Filter) is proposed for tracked grain transport vehicles. The UKF and IMU measurements are used to predict the vehicle state, while the NDT algorithm provides pose estimates for state update, yielding a fused and more accurate pose estimate. Experimental results demonstrate that the proposed mapping method reduces APE (absolute pose error) by 79.99% and 49.04% in the machinery sheds and farm access roads environments, respectively, indicating a significant improvement over conventional methods. The real-time localization module achieves an average processing time of 26.49 ms with an average error of 3.97 cm, enhancing localization accuracy without compromising output frequency. This study provides technical support for fully autonomous operation of agricultural machinery.

27 March 2024 in Agriculture
Verified
Journal Article
Open access
PDF file
SXShuaifeng Xing
Shuaifeng Xing
YYYang Yu
Yang Yu
GCGuangqiao Cao
Guangqiao Cao
JHJinpeng Hu
Jinpeng Hu
LZLinjun Zhu
Linjun Zhu
Lizhang XuLizhang Xu
Lizhang Xu
To address the issue of reduced yield in the second season caused by damaged stubbles resulting from being compressed during the harvesting process of the first season’s ratoon rice, a device for rectifying the compressed stubbles was designed. Utilizing the DEM-MBD coupling simulation method, a simulation analysis was conducted to determine the range of key parameters and verify the feasibility of the solution. Using rotational speed, forward speed, and stubble entry angle as experimental factors and stubble rectification rate and second-season yield as evaluation metrics, a three-factor, three-level Box–Behnken response surface field trial was conducted. The theoretically optimal working parameter combination was found to be a forward speed of 1.4 m/s, device rotational speed of 75 rpm, and stubble entry angle of 39°. Under these conditions, three parallel experiments were performed, resulting in a rectification rate of 90.35% in the mechanically harvested and compressed area and a second-season yield of 2202.64 ± 35 kg/hm2. The deviation from the numerical simulation results of parameter optimization was less than 5%. These findings suggest that the designed stubble rectification device for ratoon rice can meet the requirements of stubble rectification during the first-season harvest of ratoon rice. Furthermore, it provides valuable insights for reducing harvest losses in the first season and further improving the level of mechanized harvesting for ratoon rice.