Abstract:
Agricultural machinery autonomous navigation technology stands as a fundamental and core pillar enabling the advancement of precision agriculture. Its significance lies in its profound impact on enhancing agricultural production efficiency and product quality, while simultaneously reducing resource consumption and environmental footprint. This comprehensive review paper systematically examines and synthesizes the research progress in autonomous navigation technology for agricultural machinery, encompassing both domestic and international developments. The analysis places particular emphasis on dissecting the current state-of-the-art and emerging trends within two critical technological domains: navigation positioning and navigation control.Within the realm of navigation positioning, significant strides have been made. High-precision Global Navigation Satellite System (GNSS) technologies, notably Real-Time Kinematic (RTK) and Precise Point Positioning (PPP), deliver centimeter-level absolute positioning accuracy. Concurrently, machine vision approaches, leveraging both sophisticated traditional algorithms and increasingly powerful deep learning techniques for feature extraction and scene understanding, along with Light Detection and Ranging (LiDAR) systems, provide robust solutions for centimeter-level relative positioning. Recognizing the limitations of single-sensor systems in complex, dynamic agricultural environments, multi-sensor fusion strategies integrating GNSS, Inertial Navigation Systems (INS), vision, and LiDAR data have unequivocally emerged as the dominant and most effective paradigm. This convergence of data streams is essential for enhancing system resilience, reliability, and adaptability across diverse and challenging field conditions. Regarding navigation control technologies, tailored solutions cater to different machinery classes. Hydraulic steering systems remain the preferred choice for heavy-duty agricultural equipment due to their high force capabilities, while electric steering systems offer distinct advantages in terms of precision, responsiveness, and integration ease, making them increasingly suitable for medium and small-sized machinery. Substantial progress has been achieved in path-tracking algorithms. Techniques such as Model Predictive Control (MPC) excel in anticipating future states and optimizing control actions, Adaptive Pure Pursuit methods dynamically adjust look-ahead distances for smoother tracking, and intelligent optimization algorithms further enhance the accuracy and, critically, the robustness of path following. These advanced control strategies demonstrate superior performance, particularly under demanding operating scenarios like steep slopes, uneven terrain, and conditions prone to wheel slip or side-slip.Practical implementation and commercialization reflect this technological evolution. Leading international agricultural machinery manufacturers, including John Deere and CLAAS, have successfully transitioned high-precision autonomous navigation solutions into large-scale, commercially viable products widely adopted in modern farming. In China, domestic enterprises such as Huace Navigation and Shanghai Lianshi are making significant strides, actively developing and deploying navigation systems. Their progress is notably accelerated by leveraging the capabilities of the indigenous BeiDou Navigation Satellite System (BDS) across various agricultural scenarios.Looking ahead, future research and development efforts should strategically focus on several key directions: advancing intelligent, context-aware fusion methodologies for multi-modal sensor data streams; optimizing navigation algorithms specifically for highly specialized agricultural tasks and unique environmental conditions; and achieving deeper, more seamless integration of autonomous navigation with precision agricultural implements and operations. Pursuing these avenues will be instrumental in propelling agricultural machinery autonomous navigation technology towards higher levels of intelligence, broader applicability, and ultimately, greater practical utility. This trajectory is vital for accelerating the modernization and sustainable transformation of global agriculture.