Accuracy in executing a motor task, i.e., in following a given trajectory under geometrical constraints, is of great interest in work operations as well as in biomechanics applications. In the framework of the Fitts’ law research on motor tasks, experimental studies usually refer to simple trajectories which are of low interest in practical applications. Furthermore, available models lack predicting accuracy in executing motor tasks since do not systematically investigate effects of both speed and task difficulty (index of difficulty (ID)). In this paper, the authors propose a ‘Speed-ID-Accuracy’ model aiming at overcoming abovementioned limits. The model is of general validity as is based on an information-based formulation of a trajectory ID; the model proposed put into relation accuracy in task execution with a general trajectory and with the speed of task execution. Modeling accuracy, defined as standard deviation of the endpoint position, is carried out by regressing data available in the literature. The model proposed proves to be more accurate than the classical ‘Speed-Accuracy’ model in fitting available data. Such a result has been found in both numerical cases relating to ‘tunnel’ and ‘circular’ traveling tasks. Limits of data from field experiments are stressed out and future research field of investigations in work environment and biomechanics are figured out.

中文翻译：

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具有空间约束的一般轨迹运动任务后的“速度-难度-准确性”模型：基于信息的模型

在工作操作以及生物力学应用中，执行运动任务的准确性，即在几何约束下遵循给定的轨迹，非常重要。在关于运动任务的菲茨定律研究的框架内，实验研究通常指的是在实际应用中不怎么感兴趣的简单轨迹。此外，可用的模型缺乏执行运动任务的预测准确性，因为没有系统地研究速度和任务难度（难度指数（ID））的影响。在本文中，作者提出了旨在克服上述限制的“速度ID准确性”模型。该模型具有通用性，因为它基于轨迹ID的基于信息的表述；所提出的模型考虑了一般轨迹和任务执行速度下任务执行的关系准确性。建模精度（定义为端点位置的标准偏差）是通过回归文献中的数据来实现的。提出的模型在拟合可用数据方面被证明比经典的“速度精度”模型更为准确。在涉及“隧道”和“圆形”行驶任务的两种数值情况下都发现了这种结果。强调了野外实验数据的局限性，并指出了工作环境和生物力学研究的未来研究领域。提出的模型在拟合可用数据方面被证明比经典的“速度精度”模型更为准确。在涉及“隧道”和“圆形”行驶任务的两种数值情况下都发现了这种结果。强调了野外实验数据的局限性，并指出了工作环境和生物力学研究的未来研究领域。提出的模型在拟合可用数据方面被证明比经典的“速度精度”模型更为准确。在涉及“隧道”和“圆形”行驶任务的两种数值情况下都发现了这种结果。强调了野外实验数据的局限性，并指出了工作环境和生物力学研究的未来研究领域。