Optic flow has been found to be a significant cue for static observers' perception of distance travelled. In previous research conducted in a large-scale immersive display (CAVE), adding viewpoint oscillations to a radial optic flow simulating forward self-motion was found to modulate this perception. In the present two experiments, we investigated (1) whether the improved distance travelled perceptions observed with an oscillating viewpoint in a CAVE were also obtained when the subjects were wearing a head mounted display (HMD, an Oculus Rift) and (2) whether the absence of viewpoint oscillations during treadmill walking was liable to affect the subjects' perception of self-motion. In Experiment 1, static observers performed a distance travelled estimation task while facing either a purely linear visual simulation of self-motion (in depth) or the same flow in addition to viewpoint oscillations based on the subjects' own head oscillations previously recorded during treadmill walking. Results show that the benefits of viewpoint oscillations observed in a CAVE persisted when the participants were wearing an HMD. In Experiment 2, participants had to carry out the same task while walking on a treadmill under two different visual conditions simulating self-motion in depth: the one with and the other without the visual consequences of their head translations. Results showed that viewpoint oscillations did not improve the accuracy of subjects' distance travelled estimations. A comparison between the two experiments showed that adding internal dynamic information about actual self-motion to visual information did not allow participants better estimates.

中文翻译：

---

视点振动改善了静态观察者对行进距离的感知，但在跑步机行走过程中却没有。

人们发现，光学流动是静态观察者感知行进距离的重要线索。在以前的大规模沉浸式显示器（CAVE）中进行的研究中，发现将视点振荡添加到模拟向前自我运动的径向光流中可以调节这种感觉。在目前的两个实验中，我们调查了（1）当受试者佩戴头戴式显示器（HMD，Oculus Rift）时，是否还获得了在CAVE中以振动视点观察到的距离旅行感知的改善；以及（2）是否在跑步机上行走时，视线不振动会影响受试者对自我运动的感知。在实验1中，静态观察者执行距离旅行估计任务时，除了要根据先前在跑步机行走过程中记录的受试者自身的头部振动来观察视点振动之外，还要面对自身运动（深度）的纯线性视觉模拟或相同的流动。结果表明，当参与者佩戴HMD时，在CAVE中观察到的视点震荡的好处持续存在。在实验2中，参与者必须在跑步机上行走时在两种不同的模拟深度自我运动的视觉条件下执行相同的任务：一个有，而另一个没有其头部平移的视觉后果。结果表明，视点震荡并没有提高被摄对象的距离旅行估计的准确性。