Multi-Objective Optimal Design and Development of a Four-Bar Mechanism for Weed Control

Abstract

Weeds compete with crops for water, nutrients, and light consequently, have adverse effects on the crop yield and overall productivity. Mechanical weeding is the most common non-chemical method for weed control, which is applied in organic farming, and the weed cultivator is the most common implement in mechanical weeding. This study aimed to design and develop an innovative active tool to optimize the cultivation depth, which can avoid damage to crop roots and improve the key performance indicators of an inter-row cultivator. A quasi-Newton optimization method and a hybrid of the non-dominated sorting genetic algorithm (NSGA-II) and goal attainment method were separately applied to synthesize and develop a four-bar mechanism for weeding requirements. The transmission angle of the mechanism and the desired path of the weeding blade were simultaneously optimized using these multi-objective optimization techniques. The performance of the developed four-bar cultivator based on the optimization techniques was compared with the ones developed based on the classic methods and also with several conventional tools evaluated in other studies. The results showed that applying the quasi-Newton optimization method and hybrid genetic algorithm can propose a more effective weed cultivator in terms of performance indicators, namely weeding performance, mechanical damage to crop plants and cultivation depth. In addition, the optimization of the transmission angle guaranteed the smooth rotations in the mechanism’s joints.

Crop detection technologies, mechanical weeding executive parts and working performance of intelligent mechanical weeding: a review

“…This means farms require more professional labors, particularly for larger farms ( Gazoulis et al., 2021 ; Schlinker, 2021 ), which increases the labor costs. Besides, intelligent mechanical weeding equipment is the integration of multiple technologies, and due to the compatibility among different equipment, more capital investment is also needed to address the issue of technology compatibility ( Alba et al., 2020 ; Machleb et al., 2021 ; Hosseini et al., 2022 ). During the research investigation, the authors learned that Red Star Farm in Beian City, Heilongjiang Province, China once spent ¥ 2.8 million to purchase an intelligent maize weeding machine based on image recognition in 2021 (As shown in Figure 6 ), and it also needs to be equipped with professional operators and maintenance technology, which further increases the application cost ( Bawden et al., 2017 ).…”

Role of Crop-Protection Technologies in Sustainable Agricultural Productivity and Management

“…If chemical control is used in accordance with established formulas and always within limitations, it might be regarded as biological. Manual weeding is time-consuming, costly, and labor-intensive, but it is undoubtedly biological [53][54][55][56]. Thus, farmers are forced to resort to other reliable methods, such as mechanical control using weed cultivators, which is also biological [56][57][58].…”

“…Manual weeding is time-consuming, costly, and labor-intensive, but it is undoubtedly biological [53][54][55][56]. Thus, farmers are forced to resort to other reliable methods, such as mechanical control using weed cultivators, which is also biological [56][57][58].…”

Study of Differential Evolution Variants in the Dimensional Synthesis of Four-Bar Grashof-Type Mechanisms

“…Among the most important kinematic chain mechanisms is the four-bar one. Many examples of the successful use of this mechanism in real-world applications can be found in the specialized literature [13][14][15][16]. The widespread use of the four-bar mechanism is due to its ability to follow highly nonlinear closed trajectories with only one degree of freedom, in contrast to open-chain alternatives that require at least two degrees of freedom to produce similar trajectories, or closed-mechanism alternatives with a larger number of loops or degrees of freedom, thus resulting in significant savings in the cost involved in actuators and their control.…”