Study on effect of stem diameter, moisture content and age of henna plant on cutting force

Abstract

Henna (Lawsonia inermis), is cultivated in Western Rajasthan (Arid Zone). The cultivation of henna is very intensive in and around Sojat and Marwar Junction Tehsils of Pali district (average annual rainfall > 400 mm /yr.). The cultivation of henna is spread over about 32000 ha area, which fetches more than 400 million Indian Rupees of revenue every year. On maturity, the stem of henna is very woody and harvesting is performed with a sharp edge curved heavy sickle. This operation involves a lot of human drudgery with a poor efficiency. To design and develop a harvesting machine/device for henna, it is imperative to study the effect of different parameters, viz. stem diameter, age of henna plant and moisture content of the stem’s woody material on cutting force. The paper deals with interactive as well as component relationships between the cutting force, stem diameter, moisture content and age of the henna plant. The data could be fitted in a multi linear relationship between age, moisture content, stem diameter and cutting force. The model is validated well as the slope of the plot between the observed and predicted values of the cutting force is close to unity (i.e. 0.97).