To meet this increasing demand, there must be an increase in production as well. However, most farmers continue to use manual tools resulting in low productivity in addition to the associated drudgery. This has contributed to stagnation in maize production, raising concern over livelihood security for a considerable section of the population.While there are several factors contributing to the problem of low production of maize in Uganda, heavy reliance on human muscles as the main source of farm power is a major impediment . Agricultural production in Uganda is characterized by low levels of mechanization with only 10% of farmers using some form of mechanization. While the proportion of farmers in Uganda using Animal Draught Technology is relatively higher compared to use of engine power , its use is largely limited to ploughing operations .The lack of appropriate technologies for mechanized farming operations in Uganda continues to be a major challenge to the goal of increasing agricultural production. Majority of farmers are low-income smallholders, unable to afford tractor-powered equipment while most of the available draught animal powered equipments perform a single operation, making DAP and the associated tools relatively expensive as well.
Since modern agricultural equipment which is crucial to improved production is beyond the buying capacity of most smallholder farmers, there is need for low-cost equipment that can handle labor-intensive operations particularly ploughing, planting and weeding so as to increase maize production. A study conducted by concluded that in areas where farmers use DAP equipment,sawtooth greenhouse significant improvements in production can be obtained through the introduction of small-scale farm implements and machines. Similarly,argues that use of animal-drawn tools and equipment can increase yield of agricultural produce significantly and reduce labor demand in farming operations. In this paper,the process of developing and evaluating the performance of an integrated ox-drawn tool that combines a plough, planter and cultivator, for small-scalemaize farmers in Uganda is described. The cultivating unit was designed for inter-row weed control in maize fields with an inter-row spacing of 75 cm. The unit comprised of sweeps, shanks, crossbeam and beam end attachment. These components were designed using standard procedures for design of machine elements. For soil-engaging components,duck-foot sweeps were selected due to availability on the local market and their ability to manipulate soil owing to their large wing width. Arrangement of sweeps was chosen to achieve maximum weeding area between the rows without damaging the crop and was done in accordance with .
Shanks were sized basing on the maximum bending moment they are subjected to in operation which was obtained by considering the shank as a cantilevered beam carrying a point load at the end with sweeps and fixed on the plough beam. The load on sweeps was obtained as the total draft force on soil-engaging components which is the product of sweep cross-section area and unit draft for clay loam soil in friable moisture condition. The cross beam, on which shanks are attached, was designed based on maize inter-row spacingand the maximum shear force and bending moment to ensure strength and rigidity. The cultivator was tested in average plot sizes of 80 by 10 m having maize planted at an inter-row spacing of 75 cm and an intra-row spacing of 30 cm. The cultivator was adjusted to a working depth of 40 mm and hitched to the animals.During field tests, actual operating width and depth of cultivation were measured as well as the operation time and turning time. Two timers were used, one for time spent per each run along a row and the other one for total time taken to carry out the operation.This operation was replicated ten times and data collected was used for calculating the average field capacity and efficiencies.Weeding efficiency was calculated by counting weeds before and after weeding operation, measurements of weed cover, and total area of cultivation were measured. Crop damage was assessed by counting crop plant populations in each row before and after the passage of the cultivator.