基于最大差异测量法的汽车座椅坐垫舒适性探讨

Discussion on Comfort of Vehicle Seat Cushion Based on Best-worst Scaling Method

为讨论硬度、厚度等坐垫物理性能参数对汽车座椅静态舒适性的影响,开展了静态舒适性主观评价试验和体压分布客观测试。引入最大差异测量方法进行了坐垫舒适性主观评价,以减小主观随意性带来的偏差,并结合体压分布客观测试结果进行了统计分析来探讨汽车座椅坐垫舒适性。参考汽车座椅参数,制作了4种硬度和4种厚度水平的16块方形聚氨酯泡沫坐垫,搭建了模拟汽车座椅乘坐环境的舒适性评价台。选取16名被试者,按照不完全平衡区组法设计了坐垫舒适性主观评价问卷,基于最大差异测量法得到16名受试者的坐垫B-W得分。最大差异测量法能够有效避免评分量表的使用偏差,同时也保证了效率。利用XSENSOR体压测试系统测量人体座椅界面的压力分布指标,获取了16名受试者的臀部平均压力、峰值压力和接触面积等体压分布指标。主观舒适性B-W得分和体压分布指标均表明:整体上降低坐垫硬度、增加厚度能改善舒适性,但硬度降低到一定范围、厚度增加到一定范围后改善不明显,改善坐垫舒适性需要合理地设计坐垫物理特性。主客观评价数据的相关性分析表明:平均压力与主观感受的相关性最大。差异性分析结果表明:臀部体压分布指标和B-W得分的变化存在一定程度的不一致性,体压分布指标与主观舒适性间的联系规律值得进一步探讨。

In order to discuss the influence of seat cushion foam parameters(thickness and hardness)on the static comfort of automobile seats,the subjective evaluation test of static comfort and the objective test of body pressure distribution are carried out.The best-worst scaling method is introduced into the subjective evaluation of automobile seat cushion comfort to reduce the subjective arbitrary deviation,and the statistical analysis is conducted by using objective test result of body pressure distribution to discuss the automobile seat cushion comfort.Referring to the parameters of automobile seats,16 square polyurethane foam cushions with 4 hardness and 4 thickness levels are produced,and a comfort evaluation platform simulating the riding environment of automobile seats is built.Selecting 16 subjects,the subjective evaluation questionnaire of cushion comfort is designed according to the incomplete balance block method,and the B-W scores of 16 subjects are obtained based on the best-worst scaling method,which could effectively avoid the deviation in the use of the scoring scale,and also ensure the efficiency.The pressure distribution indicators of the bodyseat interface of 16 subjects such as average hip pressure,peak pressure and contact area are obtained by using XSENSOR body pressure testing system.Both the B-W scores of subjective comfort and the body pressure distribution indicators show that reducing the hardness and increasing the thickness of the cushion can improve the comfort,but when the hardness decreases to a certain range and the thickness increases to a certain range,the improvement is not obvious.It is necessary to reasonably design the physical characteristics of the cushion to improve the of the cushion comfort.The correlation analysis of subjective and objective data shows that the correlation between average pressure and subjective feeling is the largest.The result of difference analysis shows that there is a certain degree of inconsistency between the hip body pressure distribution indicator and the B-W score,and the relationship between the body pressure distribution indicator and subjective comfort deserves further discussion.