Selvaprakash Ramalingam, Devanakonda Venkata Sai Chakradhar Reddy
This chapter details a practical deployment framework centered on an edge-centric architecture for real-time crop nutrient monitoring, integrating low-cost embedded edge processors with RGB and multispectral imaging platforms mounted on drones, ground rovers, and fixed stations. The system captures high-resolution imagery at frequent intervals, employing synchronized parallel preprocessing pipelines tailored to each sensor type, including radiometric calibration, geometric correction, and spectral band registration using state-of-the-art algorithms such as enhanced correlation coefficient (ECC) and recurrent all-pairs field transforms (RAFT). Automated detection and segmentation leverages cutting-edge deep learning models, including a foundational lightweight U-Net and YOLO (You Only Look Once) with channel-wise attention and transformer-based architectures like SegFormer, augmented by hyperspectral superpixel clustering and conditional random field refinement to accurately delineate crop canopies and leaves. Edge-based inference utilizes pruned and quantized convolutional neural networks derived from the foundational model for rapid estimation of critical nutritional indicators such as chlorophyll and nitrogen indices, achieving sub-two-second latency without reliance on cloud infrastructure. The deployment process is streamlined through automated .sh, .bat, and .py scripts, enabling containerized environments, reproducible installs, and secure over-the-cloud model updates across distributed edge devices. A dedicated graphical user interface (GUI) facilitates real-time multi-platform monitoring, anomaly alerts, customizable dashboards, and integrates with Internet of Things (IoT) telemetry for dynamic system health visualization. Postprocessing algorithms incorporate advanced spatiotemporal filtering, anomaly detection with Bayesian networks, adaptive vegetation index computations, and leverage geostatistical kriging to enhance nutrient pattern resolution. Georeferenced results are securely transmitted via MQTT/HTTP protocols, supporting data federation to centralized cloud servers hosting AI-powered analytics and decision-support tools. The system supports automated variable-rate prescription map generation and real-time deployment via low-latency telemetry links to autonomous unmanned aerial vehicle (UAV) spraying platforms, enabling precision agronomy with feedback control loops and adaptive input management. Extensive field and aerial validations demonstrate robust performance under heterogeneous environmental conditions, with low mean absolute errors less than 5% in chlorophyll and nitrogen indices, validated by spectroradiometer ground truthing and UAV LiDAR (light detection and ranging) integration. This modular, scalable framework enables seamless sensor fusion, including thermal and hyperspectral arrays and continuous model refinement through federated learning and over-the-air updates, delivering an energy-efficient, resilient edge-AI platform. This comprehensive case study underscores the transformative impact of integrated image processing, edge intelligence, and automated decision systems in sustainable, high-efficiency crop nutrient management.