Gibaldi Agostino, Vanegas Mauricio, Bex Peter J, Maiello Guido
Department of Informatics, Bioengineering, Robotics and System Engineering, University of Genoa, Via All'Opera Pia, 13, Genoa, 16145, Italy.
Department of Psychology, Northeastern University, 360 Huntington Ave., Boston, MA, 02115, USA.
Behav Res Methods. 2017 Jun;49(3):923-946. doi: 10.3758/s13428-016-0762-9.
The Tobii Eyex Controller is a new low-cost binocular eye tracker marketed for integration in gaming and consumer applications. The manufacturers claim that the system was conceived for natural eye gaze interaction, does not require continuous recalibration, and allows moderate head movements. The Controller is provided with a SDK to foster the development of new eye tracking applications. We review the characteristics of the device for its possible use in scientific research. We develop and evaluate an open source Matlab Toolkit that can be employed to interface with the EyeX device for gaze recording in behavioral experiments. The Toolkit provides calibration procedures tailored to both binocular and monocular experiments, as well as procedures to evaluate other eye tracking devices. The observed performance of the EyeX (i.e. accuracy < 0.6°, precision < 0.25°, latency < 50 ms and sampling frequency ≈55 Hz), is sufficient for some classes of research application. The device can be successfully employed to measure fixation parameters, saccadic, smooth pursuit and vergence eye movements. However, the relatively low sampling rate and moderate precision limit the suitability of the EyeX for monitoring micro-saccadic eye movements or for real-time gaze-contingent stimulus control. For these applications, research grade, high-cost eye tracking technology may still be necessary. Therefore, despite its limitations with respect to high-end devices, the EyeX has the potential to further the dissemination of eye tracking technology to a broad audience, and could be a valuable asset in consumer and gaming applications as well as a subset of basic and clinical research settings.
托比艾眼控仪是一款新型低成本双目眼动追踪仪，面向游戏和消费应用领域进行推广。制造商宣称该系统旨在实现自然的眼动注视交互，无需持续重新校准，且允许适度的头部移动。该眼控仪配备了软件开发工具包（SDK），以促进新的眼动追踪应用程序的开发。我们考察了该设备在科学研究中的潜在用途。我们开发并评估了一个开源的Matlab工具包，可用于在行为实验中与艾眼控设备进行接口连接以记录注视情况。该工具包提供了针对双目和单目实验的校准程序，以及评估其他眼动追踪设备的程序。观察到的艾眼控仪的性能（即精度<0.6°，精确度<0.25°，延迟<50毫秒，采样频率≈55赫兹）对于某些类型的研究应用来说是足够的。该设备能够成功用于测量注视参数、扫视、平稳跟踪和双眼视轴辐合眼动。然而，相对较低的数据采样率和中等精确度限制了艾眼控仪在监测微小扫视眼动或实时注视相关刺激控制方面的适用性。对于这些应用，可能仍需要研究级的高成本眼动追踪技术。因此，尽管艾眼控仪相对于高端设备存在局限性，但它有潜力将眼动追踪技术推广给更广泛的受众，并且在消费和游戏应用以及部分基础和临床研究环境中可能是一项有价值的资产。
