This article points out how a driver might misperceive the curvature of a road curve if the curve is combined with a slope change that the driver does not recognize. We investigated the relationship between the apparent curvature of a road and the change of the slope, and clarified the difference between the perceived curvature and the actual curvature when the driver mistakenly believes that the slope is constant. Curves are typical road structures on which traffic accidents occur frequently, and the main cause of these accidents is regarded as excessive speed due to driver carelessness. The results of this study suggest one possible reason why drivers travel too fast on curves. Other aspects of the optical illusion that cause misperception of the curvature are also touched upon.

本文指出，如果将弯道与驾驶员无法识别的坡度变化相结合，则驾驶员可能会错误地感知道路弯道的曲率。我们研究了道路的视在曲率与坡度变化之间的关系，并阐明了当驾驶员错误地认为坡度恒定时，感知曲率与实际曲率之间的差异。弯道是经常发生交通事故的典型道路结构，由于驾驶员的疏忽，这些事故的主要原因被认为是超速行驶。这项研究的结果表明了驾驶员在弯道上过快行驶的一个可能原因。还涉及导致错觉曲率的错觉的其他方面。