Performance evaluation of disc ridging tractive force model in loamy sand soil using sensitivity measured parameters

Abstract: Disc ridging operations in a loamy sand soil, at tillage speeds of 1.94 m/s, 2.22 m/s and 2.5 m/s, using trace tractor techniques, were conducted.  The dependent and independent variables involved in the models were measured.  The sensitivity of measured parameters was used for evaluating performance of developed models which described the tractors tyre-soil- interactions parameters.  Results showed performance of the wheel-tractors tractive force models having sensitivity coefficients ranging from -0.00164 to 0.2505, -0.00698 to 0.0979 and -0.00258 to 0.2595 for Disc ridging, with all the independent variables at 1.94 m/s, 2.22 m/s and 2.50 m/s tillage speeds respectively.  The lowest sensitivity coefficient of -0.00698 to 0.0979 was obtained at speed of 2.22 m/s.  This indicates that tillage speed of 2.22 m/s is the best for disc ridging operation.  Results showed that performance efficiencies increase with decreasing sensitivity coefficient values.   Keywords: modelling, tractive force, disc ridging, performance, tillage, loamy, sand, soil, sensitivity measurement, soil moistur