Sustainable and Energy-Efficient Automation in Mechanical Weeding: A Review of Manual Implements to Smart Robots

The increasing problems of labor shortages and environmental concerns, and a rising demand for sustainable food production have catalysed the development of automated mechanical weeding solutions. This paper is a systematic Review of technological evolution toward energy efficiency automatic wheel hoes, a very significant area in agricultural robotics. This review analyzes the spectrum of weeding technologies through the unifying lens of energy efficiency Operational viability and sustainability rely on this as a key metric. The review synthesizes findings to demonstrate that a system-level approach encompassing prime mover selection, mechatronic design, traction optimization, and advanced energy management is essential. Key findings indicate that battery-electric systems can achieve high weeding efficiency of 97 percentage with a far lower specific energy consumption than engine-powered counterparts. Furthermore, the integration of Battery Management Systems, high-efficiency wireless power transfer (WPT), and solar Recharging provides a feasible avenue to achieve operational feasibility. The review identifies unresolved challenges such as the influence of soil conditions on tractive efficiency and the energy cost of precision guidance. We conclude by delineating future research imperatives: adaptive control systems, standardized energy metrics, and hybrid human-robot workflows to optimize the energy budget of modern farming.