视线交互中两类扫视运动的人机工效评估研究

Evaluation of Effects of Centripetal and Centrifugal Saccades on Human Performance in Gaze-based Interactions

Fitts法则是人机交互领域预测人机工效的一个有效模型,在许多交互方式中都得到了验证,是传统人机工效研究的理论基础。然而在视线交互中,由于眼动肌肉神经控制机制与肢体运动不同,Fitts法则并不适用。近两年的相关研究提出了一个新的专门针对视线点击任务的难度指数IDeye,它比经典的Fitts指数更能准确预测视线交互的工效。然而,在新模型的有效性验证实验中并没有考虑两种典型的扫视运动(向心和离心运动)的差异。为此,在前期研究的基础上设计组织实验,验证了视线交互中离心和向心这两种眼球运动所带来的人机工效和稳定性的差异,并证实新的IDeye模型仍然能有效预测单纯的离心或向心扫视条件下的人机工效,是对视线交互工效研究的重要补充。

Fitts＇ law is an effective model to predict human performance in the field of human-computer interaction （HCI）. Its effectiveness has been confirmed in many situations, and it is the theoretical basis to study the human performance in HCI. However,due to the different muscle controlling mechanisms of eyes and limbs,Fitts＇ law cannot be applied to the pointing task in gaze-based interactions. Recently, Zhang etc proposed a new index of difficulty （IDeye） that can effectively model the human performance in dwell-based eye pointing. However, their model dose not specifically take account of the differences of the two kinds of saccades （i. e. centripetal and centrifugal saccades） involved in eye pointing. This paper aimed to investigate the different performance under the different conditions of the two typical saceadic eye movements： saecades toward the primary position （centripetal） and away from the primary position （centrifugal）. Carrying out an experiment, we confirmed that there is significant difference in moving time between these two eye movements, and that the IDeye model can still accurately model the performance even in the situation of pure centripetal or centrifugal saccades. This work is necessary to complete the study of modeling dwell-based eye pointing, and it further confirms the suitability and effectiveness of the IDle model for gaze-based interactions.