Optimizing the working performance of a boat-type tractor using central composite rotatable design and response surface method

Abstract Optimization of the structural and working parameters for a boat-type tractor is essential to improve the working performance and reduce the energy consumption of the agricultural machinery. To apply the central composite rotatable design and response surface method, the individual and interactive impacts of grounding pressure (X1), sliding speed (X2), depth of surface water (X3), curvature radius of the bow (X4), and grounding angle (X5) on the sliding resistance and subsidence depth of a self-designed boat-type tractor were assessed. An analysis of variance test indicated that the sliding resistance and subsidence depth were significantly sensitive to all independent variables except X4, and the contribution rates of a single factor on the sliding resistance and subsidence depth were ordered as X1 > X5 > X2 > X3 > X4. The terms X4X5 and X1X5 were the only significant factors (p