Haptic Perceptual Instruments

触觉是指一个人通过身体对自己的身体以及对身体的依附的感知。这个术语包含了通常所说的“触摸”，以及更多的东西。例如，没有视觉的好处，一个人可以明显地意识到他四肢的方向，一个人可以意识到被挥舞和举起的物体的空间特性。这些感知能力是一种被称为动态触摸的触觉形式的表达。它之所以被称为肌腱，是因为它的基础是肌肉和肌腱的变形，以及随后在力的作用下激活它们的受体。力量要么来自肌肉，要么来自环境，或者两者兼而有之。由于四肢在关节周围运动的方式，力在很大程度上是旋转的。本研究将讨论动态触摸的知觉成就及其与肢体运动的旋转动力学的关系。重点将放在这些成就与机械量和转动量的关系上，特别是惯性张量和姿态旋量。张量表示物体对旋转的抵抗力。旋量以与组合三维旋转的特殊物理规则一致的方式量化对象相对于某个参考系(例如，手)的方向。一个主要的论点是，在通过挥舞或举起对物体空间尺寸的不可见感知中，与手相关的触觉子系统发挥着智能仪器的作用。它巧妙地利用了物理定律和物理量，这些物理量在物体被挥舞和举起时不会改变。在一些基本的方法中，参与者将挥舞一个看不见的物体来感知它的重量、长度、宽度或形状。参与者将通过分配相对于标准对象的数字或通过调整(可见的)可移动表面或指针来量化所感知的属性来回应。通常，看不见的物体将是一组杆，可以通过精确放置连接的金属环来操纵这些杆，以产生任何所需的惯性张量。在其他基本方法中，参与者将尝试将不可见的上肢或肢体段定向到另一条不可见的肢体。此外，大多数方法将涉及获取所用物体的运动数据和肢体运动，并通过非线性相空间重建过程进行分析。主要目标将是确定(1)支配重量知觉的动态变量；(2)无视觉的形状知觉的成就和局限；(3)通过特定经验公开和隐蔽地调整动态触摸；以及(4)感知姿势稳定性的基础。理解控制动态触摸的原理应该会丰富我们对物理约束的理解，这些约束必须在感知系统的计算和神经建模中得到尊重。它将提供关于躯体感觉障碍以及假肢和机器人肢体设计的新假说的来源。这样的理解可能还会促使人们更深入地研究生物感知-行为系统形成的物理原理，以及利用它们的认知和神经限制。

Haptic perception refers to the perception one has of one's body, and of attachments to it, by means of the body. The term incorporates what is commonly meant by "touch," and more besides. For example, without benefit of vision, one is obviously aware of the directions of one's limbs and one can be aware of the spatial properties of objects that are wielded and hefted. These perceptual abilities are expressions of a form of haptic perception referred to as dynamic touch. It is so called because of its basis in the deformation of muscles and tendons, and the consequent activation of their receptors, by forces. The forces arise from either the muscles or the environment or both. Because of the ways in which limbs move around joints, the forces are largely rotational.This research will address the perceptual achievements of dynamic touch and their relation to the rotational dynamics of limb movements. The focus will be on the relation of these achievements to mechanical and rotational quantities, in particular the inertia tensor and attitude spinor. The tensor quantifies an object's resistance to being rotated. The spinor quantifies an object's orientation relative to some reference frame (for example, the hand) in a manner consistent with the special physical rules for combining three-dimensional rotations. A major thesis is that, in the nonvisible perception of an object's spatial dimensions by wielding or hefting, the hand-related haptic subsystem behaves as a smart instrument. It cleverly capitalizes on physical laws and on physical quantities that do not change as an object is wielded and hefted. In some of the basic methodologies, the participants will wield an unseen object to perceive its weight, length, width, or shape. Participants will respond by assigning numbers relative to a standard object or by adjusting (visible) movable surfaces or pointers to quantify the perceived properties. Often, the unseen object will be a configuration of rods that can be manipulated through the precise placement of attached metal rings to produce any desired inertia tensor. In other basic methodologies, the participants will attempt to orient a nonvisible upper limb or limb segment to another nonvisible limb. Most methodologies will involve, additionally, the acquisition of motion data on the wielded objects and limb movements and analysis by nonlinear phase-space reconstruction procedures. The major objectives will be the determination of (1) the dynamical variables governing the perception of heaviness; (2) the achievements and limits of shape perception without vision; (3) the tuning of dynamic touch, overtly and covertly, by specific experience; and (4) the basis for perceived constancy of postures. Understanding the principles governing dynamic touch should enrich our appreciation of the physical constraints that must be respected in computational and neural modeling of perceptual systems. It will provide a source of new hypotheses about somatosensory disorders and about designs for prosthetic and robot limbs. Such understanding might also be expected to motivate more intensive study of the physical principles formative of biological perception-action systems and of the cognitive and neural constraints that exploit them.