Development of a variable rate fertilizer applicator for precision farming | |
| Author | Supana Pugasap |
| Call Number | AIT Thesis no.AE-05-09 |
| Subject(s) | Precision farming Fertilizers--Application |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. AE-05-09 |
| Abstract | The traditional fertilizer application systems arc based on the resources management at uniform rate, which may not match with the actual nutrient variability across the field. The precision farming concept with the help of variable rate technology offers solution to this problem by treating with actual fertilizer rates for site-specific crop needs. The potential importance of this method is to create profitability by decreasing input costs and high crop yields while reducing the environmental and land degradation. Variable rate applicators have been available in the developed countries with high technology components at high cost. The necessity of user skill and high cost has created the infeasibility in adoption in developing countries. A low cost prototype applicator was developed, its performance was evaluated and the cost-benefit analysis was done in this study to overcome some of those constraints and to check the adoption feasibility. The prototype applicator was designed to simultaneously spray three types of liquid fertilizers at variable rates. It consisted of three 30 liter concentrate tanks (N-P-K), one 200 liter carrier tank (water), associated with positive displacement pumps, piping and other control accessories mounted on a cart which could be pulled by a small 4-wheeled tractor or a power tiller. The application rates were controlled through an operator interface with 3x3 switch control system. The operator could change the three concentrates independently at three rates across the field based on the information interpreted on a GIS nutrient application map. The three levels of N-P-K fertilizer rates that could be applied were 25, 40 and 60 kg/ha, respectively. Ground speed compensation was included using a speed sensory system connected to the control system. It was observed that the applicator performed satisfactorily at higher forward speeds of 4.2 and 6 km/h. The fabrication cost of the prototype applicator was amount to be $ 800. In comparison with manual fertilizer application, the break-even area for the developed applicator was 12 ha. In the simulation done for the case study with 42 ha of single season soybean crop, the pay back period was found to be 1 year. The net return gain by reduced fertilizer and improved yield was about 31 $/ha. It was recommended to have further refinements in the applicator design in order to reduce the lag-time error and to improve performance |
| Year | 2005 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. AE-05-09 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Jayasuriya, Hemantha P.W.; |
| Examination Committee(s) | Salokhe, Vilas M.;Kittinun Unnanon; |
| Scholarship Donor(s) | Asian Institute of Technology Fellowship; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2005 |