The Form Design And Kansei Evaluation Of Wheeled Tractors Based On The Front Face Characteristic

For a long time,the design of agricultural machinery products has considered more about how to realize the basic functions of the products,and has not paid enough attention to the form design,which has led to the traditional agricultural machinery products giving people the impression of rough work,heavy body,and lack of artistic beauty.This problem is particularly acute with Wheeled Tractors that work as the main agricultural power machine.With the improvement of the level of agricultural mechanization in China and the expansion of the global sales market,it has become an important development direction to improve the quality of wheeled tractors form design,enrich the surface connotation of the form,enhance the Kansei cognition of people on the machine,and enhance the brand,which puts forward higher requirements for wheeled tractors form design and evaluation methods.In terms of wheeled tractors form design,the surface of the form is complex,and is based on engineering design.Moreover,in the conceptual design stage,the repeated modification of the form design is insufficient,the research on the innovative design is less,the degree of user participation in the form design is low,the design requirements and concepts are difficult to integrate into the design process,and the lack of intelligence and interaction for the wheeled tractors shape design features Design software.In terms of evaluation,the evaluation form is monotonous,there is lack of evaluation of user Kansei information,quantitative research is insufficient,and the evaluation results sometimes have a large gap with the actual situation.Focusing on the morphological characteristics of wheeled tractors,this thesis puts forward a new method for wheeled tractors form design and evaluation,and initially constructs a corresponding design and evaluation system.The main research contents and conclusions of the thesis are as follows:(1)Aiming at the complex surface of wheeled tractors and the difficulty of user participation in conceptual design and innovative design,this study proposes to use the front face of the wheeled tractors as the research object to realize the form design and evaluation system,and proposes the method of extracting the front face form feature elements.Using questionnaire survey method,82 research sample sets,and 20 feature extraction sample setswere obtained;using the morphological analysis method,the combination of user participation and graphics processing,the morphological features of the front face of the wheeled tractors were extracted;using the combination of inductive analysis method,comparative analysis method,and structural analysis method,the morphological characteristics and line type of Wheeled Tractors were obtained.There are 4 types of hoods,11 types of headlights,2 types of cabs,5 types of hood ventilation grille,3 types of cab roofs,and 3 types of cab ceiling lights.The overall and morphological characteristics of representative samples are drawn in CAD environment as a basis for the development of form design and Kansei evaluation systems.(2)On account of the monotony of wheeled tractors form design and lack of evaluation of user Kansei information,this study proposes a multi-dimensional sensible semantic space establishment method for wheeled tractors form design,and establishes a Kansei semantic space.Using literature reading method,interview method,focus group,brainstorming,questionnaire survey,and group experiment,the sensuous semantic description was obtained and optimized,and the semantic vocabulary with unreasonable description or similar semantics was optimized from 310 Kansei evaluation words.The five categories of Kansei semantic vocabulary enrich types of Kansei evaluation establish a five-dimensional semantic space represented by streamlined-geometric,minimalistic-complex,modern-traditional,lightweight-heavy,and active-dull.(3)Regarding the problem that quantitative research on modeling is absent,which is mainly reflected in the lack of constructing model of form design elements and users' Kansei evaluation,the evaluation results sometimes have a large gap with the actual situation.Taking the tractor's front face characteristics as form design elements,this paper proposes six form design elements as input,and five groups of Kansei semantic evaluation results as output,Back Propagation Neural Network(BP-NN),Support Vector Machine(SVM),Back Propagation Neural Network optimized by Genetic Algorithm(GA-BP),and Support Vector Machine by Genetic Algorithm(GA-SVM)are proposed to construct the relational model.The mean square errors of four models predicting are 0.5299,0.2564,0.2936,and 0.1035,the average errors are 0.537,0.1859,0.2936,and 0.1018.The prediction root mean square and average error of GA-SVM are the smallest,and the predicted value is consistent with the actual Kansei semantic evaluation value,which can be used for the development of the Kansei evaluation system.(4)On account of the issue that the design of the wheeled tractors shape is mainly based on engineering design,the repeated modification of the pattern design of the conceptual design stage is insufficient,the research on the innovative design link is less,andthe problem of the user-oriented wheeled tractors form design method is low,this study proposes a method based on GA to realize form design and optimization based on wheeled tractors morphological features.Taking the morphological characteristics of the wheeled tractors as the gene,the fitness value is calculated by the satisfaction model,and the optimal gene group is obtained through continuous selection and optimization.The experimental results show that GA obtains the optimal combination of form design after 50 iterations.This model provides a new way to improve the automation of wheeled tractors form design.(5)In view of the fact that the degree of user participation in form design is low,its design requirements and concepts are difficult to integrate into the design process,and there is a lack of intelligent and interactive design and evaluation software for wheeled tractors shape design features,based on genetic algorithm to construct morphological design model and multi-algorithm to construct Kansei semantic evaluation model,Matlab software development tool is used to realize an interactive wheeled tractors form design and evaluation process system prototype,and the developed system can be participated by ordinary users to design and evaluate,enjoys good interactive performance and intelligent computing capabilities,as well as can better improve the automation of wheeled tractors form design and evaluation.Through case studies,the functions of the system were tested and demonstrated.