基于距离认知的虚拟现实指点交互行为研究

Interactive Behavior Research of Pointing Cursors in Virtual Reality Based on Distance Cognition

虚拟现实中自我中心距离的准确认知、指点光标的合理设计对用户的交互体验及任务执行效率起着至关重要的作用.结合费茨定律在三维指点任务中的拓展研究,以指点光标类型、自我中心距离、目标大小及方位角作为变量,展开虚拟空间指点交互实验研究.首先提出指点光标、自我中心距离、目标大小及方位角的不同对自我中心距离认知准确性及目标指点速度存在影响等6个假设.其次通过分析实验数据所得目标指点准确度及目标指点时间,讨论自我中心距离认知准确度与目标指点速度的变化规律.实验结果表明,在虚拟现实中,指点光标、目标大小对自我中心距离认知准确度、目标指点速度均有显著性影响,目标方位角、自我中心距离仅对目标指点速度有显著性影响;指点光标与自我中心距离对自我中心距离认知准确度及目标指点速度均有双向交互效应.两种指点光标的目标指点时间均与难度系数线性正相关,即符合费茨定律在三维指点任务中的扩展模型.该结论揭示了自我中心距离认知的影响因素,能够有效指导虚拟现实中交互方式及三维指点任务的设计.

In virtual reality, the accurate cognition of egocentric distance and the reasonable design of pointing cursors play crucial roles in the user’s interactive experience and task execution efficiency. Given the extended research of Fitts’ law in three-dimensional pointing tasks, the interactive experiment of pointing cursors in virtual space is carried out taking the types of pointing cursors, egocentric distance, target size, and azimuth angles as variables. First, six hypotheses are proposed. For example, the difference among pointing cursors, egocentric distance, target size, and azimuth angles could affect the cognitive accuracy of egocentric distance and target pointing speed. Second, the target pointing accuracy and target pointing time are obtained based on the experimental data, and the change law of the cognitive accuracy of egocentric distance and target pointing speed is discussed. Experimental results show that in virtual reality, the pointing cursor and target size all have a significant effect on the cognitive accuracy of egocentric distance and the target pointing speed, while the target azimuth angles and egocentric distance could only significantly affect the target pointing speed.The pointing cursor and egocentric distance has a two-way interactive effect on the cognitive accuracy of egocentric distance and the target pointing speed. The target pointing time of the two kinds of pointing cursors is linearly and positively correlated with the difficulty coefficient, which is consistent with the extended model of Fitts’ law in threedimensional pointing tasks. This conclusion reveals the influencing factors of egocentric distance cognition, which can effectively guide the design of interactive methods and three-dimensional pointing tasks in virtual reality.