# Optimization of Design Parameters Using SQP for an Agricultural Pipe Extraction Device
## 1 Introduction  
When a crop grows and produces fruit, it cannot bear its weight and falls down. The fruit touches the soil and becomes soft or rotten. In particular, during the summer and rainy seasons, crops are frequently exposed to typhoons or rain and wind, which increases the probability of crop damage. Therefore, agricultural pipes are widely used for the healthy growth of crops. The use of pipes in agriculture is a major way to prevent crops from being bent or overturned in the wind and rain and is directly related to improving yields. However, in winter, when farming is over, the agricultural pipe must be removed from the hardened bottom of the farmland. It is difficult to remove the pipe without using a tool because a large force is continuously required. Therefore, methods of removing agricultural pipes using various tools have been proposed. Representative examples include a crop-holder recovery device and a pepper-support extraction device. These existing devices allow the removal of an agricultural pipe by pulling the lever or applying force by hand. In this study, an agricultural pipe extraction device (hereafter referred to as an extraction device) was proposed and optimized. This extraction device is operated by foot, unlike conventional hand-operated instruments. Compared to existing devices that require pulling the lever by hand, the stepping method has the advantage that the agricultural pipe can be easily removed with a small force using an appropriate link. In particular, considering that the work is performed continuously, the effect of reducing the workload experienced by users is expected to be significant, as compared to the existing method. Optimization of the agricultural pipe extraction device was performed in the direction of minimizing theforce required during operation. To this end, ergonomic design variable constraints were applied to prevent using excessive force when operating the extraction device. Various studies have been conducted on parameter optimization to minimize the force targeting the link structure. [PERSON] and [PERSON] (2010) [1] conducted a study on the optimal design of a tractor clutch-link system to minimize the pedal force generated when the clutch pedal was depressed. The link system was formulated, and a feasible direction method was used as an optimization algorithm. The operating force was reduced by 14% by optimizing the clutch system of commercial tractors. [PERSON] et al. (2013) [2] performed a link structure optimization study for a four-section link manipulator for starfish collection and presented a mechanism that improved the collection distance set as an objective function by 56%. [PERSON] et al. (2011) [3] optimized a link structure with a maximum walking stride for a walking robot. The four-section link theory and the Janssen mechanism were applied for optimization, and through this, it was possible to propose the position and length of each link with a 214% improved walking stride, as compared with the existing model. [PERSON] et al. (2022) [4] conducted a DEM simulation to simulate the draft force, and it was concluded that the draft force increased with an increase in working depth and forward speed. [PERSON] et al. (2022) [5] conducted research to optimize the bucket size of a metering device for each group of garlic cloves investigated was determined using MBD simulation. Using the developed garlic clove 3D models, a simulation was performed by increasing the angle of the bucket size control guide, and the angle immediately before the descent of the garlic clove was regarded as the optimal angle. [PERSON] et al. (2014) [6] set and optimized the position and length of latches as design variables to shorten the opening time of circuit breakers. For optimal design, an interlocking model of ADAMS (Automated Dynamic Analysis of Mechanical Systems) and VisualDOC was constructed, and optimization was performed using GA as a nonlinear optimization algorithm.