Design of a Spring-Finger Potato Picker and an Experimental Study of Its Picking Performance

Abstract

To address the problems of low pickup rates and high rates of wounds in the mechanised harvesting of potatoes under sectional harvesting conditions, a spring-finger potato picker was designed and its overall structure and working principles were described. The kinematic principle of the spring-finger was analysed based on the picking constraints, and the kinematic parameters of the picker were determined. A response surface Box–Behnken Design test design was used to carry out a quadratic orthogonal rotational test, with the speed of the spring-finger, the forward speed of the machine, and the embedded depth as test factors, and the loss rate and the wounded potato rate as evaluation indicators. The test results were optimised and analysed. When the spring-finger speed was 19.57 r/min, the forward speed was 0.61 m/s and the embedded depth was 71.31 mm, the loss rate was 1.18%, and the wounded potato rate was 5.71%. The optimised data were verified, and the results showed that the loss rate of the spring-finger potato picker was 1.48% and the wounded potato rate was 4.98%, meeting the potato picking and harvesting requirements. The research can provide a theoretical basis and design reference for the development and application of sectional potato harvesting machinery.

Design and Experiment of Toggle Lever-Type Potato Picker

“…As shown in Figure 14c, the potato damage rate decreases with an increase in the shovel angle. According to Wang's research [18], the angle of the shovel directly affects the operational efficiency of the potato harvester. A larger shovel angle increases the amount of material fed into the shovel per unit time, thickening the soil layer on the picker, thereby enhancing the protective effect of the soil on the potatoes and reducing the potato damage rate.…”

“…Consequently, the BMP-80 SA1P1Y5 hydraulic motor is selected. The shovel angle is a crucial parameter [17,18] that influences both the depth of soil penetration during picking and the resistance encountered by the machine during operation. A suitable shovel angle ensures an optimal amount of soil-potato mixture enters the picker, thereby minimizing potato damage while enhancing picking efficiency.…”

“…Potato damage rate: The mass of the damaged potatoes is divided by the total mass of potatoes in the experimental area to calculate the percentage of damaged potatoes in total, according to Equation (18).…”

“…Soil particles were generated in the area above the box, with a delay of 1 s to allow for soil stabilization. The soil parameters can be collated from the literature [18] as shown in Table 5. In this experiment, 20 potato models were added, allowing them to freely fall onto the soil surface to create a potato-soil mixture of particles.…”

“…As the shovel angle increases, the peak force on the potatoes decreases linearly (Figure 17c). According to Li's research [18], under constant conditions, increasing the shovel angle increases the amount of soil fed into the picker per unit time, leading to an increase in soil thickness. Soil can provide a buffering and protective effect on the potatoes [31].…”