Reliability-based optimization design of the agricultural machinery parts based on key quality characteristics

Quality is an important factor in market competitiveness of the agricultural equipment. This paper quantifies the fuzzy concept of customer requirements and incorporates it into reliability design of the agricultural machinery parts, and presents a reliability-optimization method based on key quality characteristic. Firstly, the integration model of quality function deployment (QFD) and axiomatic design theory can be optimized by using fuzzy regression theory, and the key quality characteristics of each design phase of the agricultural machinery can be extracted. Secondly, guided by the reliability-optimization theory and stress-strength interference model, a mathematical model of the reliabilityoptimization design can be built based on key quality characteristics of agricultural machinery parts. Finally, the adaptive particle swarm optimization (APSO) algorithm with constraints is employed in the optimization analysis of the mathematical model. This paper analyzed the design process of key quality characteristics of rice transplanting machine's dial shaft, and respectively calculated the optimal design parameters when the reliability was 0.995 and 0.999. Compare to the Monte-Carlo test, the relative error of the dial shaft optimal cross-sectional area is 2.53% and 2.40%. The efficiency and effectiveness of the proposed analysis of the key quality characteristics are illustrated in the reliabilitybased optimization design of the agricultural machinery parts.