Abstract:
Lack of man power has been identified as one of the major problems for the sustainability of
the Sri Lankan paddy industry. Hence transplanters and seeders were well developed as a step for
mechanization. However, weeding method is still not well developed up to mechanization. Therefore, our main
objective is to design and fabrication of a power weeder. Weeding ability will be optimized by weeding three
rows simultaneously. The machine is designed to use in the fields, cultivated by using mechanized seeder or
mechanized transplanter introduced by Farm Machinery Research Centre (FMRC), Sri Lanka.
The double-action weeding drums will be driven by a small 1.3 kW gasoline engine, that can enable removal of
weeds, while facilitating the forward motion of the machine. In addition, the conical shaped weeding drums will
be designed to loose-up soil without harming the paddy. Totally six drums will be used, in such a way that rear
three drums have high angular velocity with respect to the front drums.
A novel maneuvering method for row changing when the machine is in paddy fields also introduced in the
design. More than 5-fold improvement of weeding efficiency in terms of weeding time is expected in this
design. Further, a significant improvement of weeding quality is also expected in this design.
