Groundnut Digger cum Inverter: A Concept

Lakhani AL¹*, Vala VS², Parmar NB³, Kathiria RK⁴ and Vadher AL⁵

¹Department of Farm Machinery and Power Engineering, Junagadh Agricultural University, India ²Agricultural Mechanization Division, India ³Department of Farm Engineering, Junagadh Agricultural University, India ⁴Directorate of research, Junagadh Agricultural University, India ⁵Department of Farm Machinery and Power Engineering, Junagadh Agricultural University, India effect of aflatoxin in pods due to the saturated moisture.

Keywords: Groundnut Digger; Digging Unit; Conveying Unit; Inverting Mechanism

Introduction

Groundnut (Arachis hypogaea), a key oilseed and cash crop, is cultivated primarily for its high content of edible oil, proteins, and carbohydrates Lakhani AL, et al. [1]. It serves as a significant source of essential nutrients and remains an economically accessible commodity. Groundnut seeds contain 22-30% protein and 44-56% oil on a dry weight basis, making them a rich source of macronutrients. Additionally, they are abundant in minerals such as phosphorus (P), calcium (Ca), magnesium (Mg), and potassium (K), along with vitamins E, K, and various B-complex vitamins. Groundnut harvesting is typically performed when a majority of the plant’s leaves turn yellow, and the pods reach full maturity, becoming firm and hardened. Groundnut develops its fruit below the soil surface, necessitating excavation for pod retrieval. Typically the groundnut pods are situated at a depth of 7 to 10 cm beneath the soil, in a region referred to as the “pod zone” Lakhani AL, et al. [2]. This zone requires precise mechanical or manual digging operations to bring the pods to the surface for harvesting.

In many regions, groundnut harvesting is predominantly carried out using traditional methods, where the plants are manually uprooted using labor, then bundled and left to dry to facilitate the manual stripping of pods from the plants. This manual process, including harvesting and threshing, typically requires 84 man-hours per hectare. A significant issue associated with this method is labor scarcity during the harvesting period, which can lead to delays. These delays, caused by the non-availability of labor at peak harvest times, can result in substantial yield losses for farmers Padmanathan, et al. [3].

Mechanical harvesting of groundnut involves the use of equipment such as blade-type harvesters and digger- shakers. The digger-shaker performs three operations simultaneously: it penetrates the soil to uproot the groundnut crop, shakes the plants to remove soil from the pods, and arranges the uprooted plants into windrows. The operational capacity of the digger-shaker ranges between 0.6 and 0.8 hectares per hour, depending on field conditions.

While traditional groundnut harvesting methods are labor-intensive, time-consuming, and physically demanding—requiring workers to uproot plants in a bent posture—the blade-type and digger-shaker harvesters reduce labor and time by mechanizing the uprooting process. However, manual labor is still required for subsequent operations, such as collecting the plants and inverting them for drying. The inverting process is critical in preventing aflatoxin contamination in the pods after digging.

To optimize groundnut harvesting, complete mechanization is proposed as a solution. This would involve the development of a groundnut harvester capable of not only uprooting the plants but also conveying and inverting them efficiently, thereby reducing labor costs and improving both productivity and profitability. Factors influencing the design of groundnut harvester are as follows.

Result and Discussion

The conceptual groundnut digger is designed to perform digging, conveying, and inverting of the plants simultaneously, thereby reducing both time and labor costs associated with groundnut harvesting. Initial evaluations of the conceptual design have demonstrated its effectiveness. To further assess the machine’s productivity in groundnut harvesting, it must advance through the subsequent phases of design, including preliminary design, detailed design, prototype development, testing, and performance evaluation.