Fertilizer monitoring using micromachined cantilever

Venkatesh K.P. Rao


Department of Mechanical Engineering, Birla Institute of Technology and Science, Pilani, 333031-Rajasthan, India


(Manuscript received 16 June 2019; accepted for publication 1 August 2019)


Abstract. In this study, we will create a grid of micro electro-mechanical (MEMS) sensors, which will measure the contents of soil, especially urea. This will inform the farmers about the condition of soil in real time, and thus allowing them to know how much fertilizer they need to add. MEMS sensor is placed in the soil to measure the soil content by chemical reaction with the fertilizers; its accuracy can be improved if these sensors are placed on multiple points, i.e., they are placed in a grid. In the present study, we designed micro-cantilever based gas detectors, to detect ammonia present in the fertilizers. Several designs were proposed to find the best fit for this purpose. Numerical studies have been carried out on the proposed designs, to evaluate the displacement sensitivity and the voltage developed in the piezoelectric layer, and the triangular cantilever was found to be the most sensitive cantilever for that purpose.