Appropriate length setting for road landscape

In order to explore the maximum setting distance for landscape, the research was carried out in lab which could simulate the second-grade road in real world. Five experiment scenes were designed according to stimulation interval from 1 to 40 kilometers. Each subject was required to drive in a scene randomly at the same time in a day. The stimulation density and heart rate were used to measure road environment. The relationship between heart rate and stimulation density was established. The results show that the degree of fatigue increases during driving time, but the degree increases differently with road environment, which is in consistency with Hancock and Warm U model, and the best interval is 7 km, which means that the heart rate increases whenever interval is larger or smaller than 7 km. The best interval from this study can provide reference for road environment improvement and safe driving.