Faculté des Sciences du Sport, Université de la Méditerranée, Marseille, France.
Exp Brain Res. 2010 Apr;201(4):763-80. doi: 10.1007/s00221-009-2092-y. Epub 2009 Dec 1.
The coordination of direction and speed of self-motion when intercepting a target moving parallel to the ground plane was examined. Subjects viewed a computer-generated environment comprised of a textured ground plane and a moving target. Turning rate was controlled using a steering wheel and speed was controlled using a foot pedal. It was hypothesized that these two degrees of freedom would be coordinated such that the speed required to intercept the target (i.e., the ideal speed) would be maintained below the subject's maximum possible speed. As predicted, subjects turned toward the target when ideal speed was less than maximum speed and ahead of the target when ideal speed was greater than maximum speed. When behavior was compared across groups with different maximum speed capabilities, it was found that the ratio of ideal to maximum speed was invariant across groups at critical points of both steering and speed adjustments. Finally, subjects rapidly recalibrated to a sudden increase or decrease in maximum speed. The results suggest that actors coordinate steering and speed during interception in a way that takes into account the limits on their action capabilities. Discussion focuses on the role of calibration and the implications of the present findings for existing models of visually guided interception.
当拦截与地面平行运动的目标时，对自我运动的方向和速度的协调进行了研究。被试者观看了一个由纹理地面和运动目标组成的计算机生成环境。通过方向盘控制转弯率，通过脚蹬控制速度。研究假设这两个自由度将协调一致，以保持拦截目标所需的速度（即理想速度）低于被试者的最大可能速度。正如预测的那样，当理想速度低于最大速度时，被试者会转向目标，而当理想速度大于最大速度时，被试者会领先于目标。当将具有不同最大速度能力的组之间的行为进行比较时，发现在转向和速度调整的关键点处，理想速度与最大速度的比值在各组之间是不变的。最后，被试者迅速重新校准到最大速度的突然增加或减少。结果表明，参与者在拦截过程中以一种考虑到其行动能力限制的方式协调转向和速度。讨论集中在校准的作用以及本研究结果对现有视觉引导拦截模型的意义。
