In this paper, we survey the work in robotic grasping related areas that has been done over the last two decades, with a bias toward the development of the theoretical framework and analytical results in this area. In addition we assess the state of the art in this area and outline some of the important open problems.

Robotic hands are very flexible mechanisms. Because of this flexibility, it has been difficult to automate the process of acquiring objects using these robotic hands. Each new grasping problem is too complex to analyze without the use of good heuristics. Constraints due to target object geometry, environment geometry, hand kinematics and geometry, and a task description must all be considered when forming a solution. One tempting

In this paper we consider the detection of small surface features, such as ridges and bumps, on the surface of an object during dextrous manipulation. First we review the representation of object surface geometry and present de#nitions of surfacefeatures basedon local curvature. These de#nitions depend both on the curvature of the robot #ngertips and the object being explored. We also show that the trajectory tracedbya round #ngertip rolling or sliding over the object surface has some intrinsic properties that facilitate feature detection. Next, several algorithms based on the feature de#nitions are presented and compared. Finally, we present simulated and experimental results for feature detection using a hemispherical #ngertip equipped with an optical tactile sensor. 1 Introduction Haptic exploration is an important mechanism by whichhumans learn about the properties of unknown objects. Through the sense of touch, we are able to learn about characteristics such as object shape, s...

Most of the algorithms used in grasp planning, force optimization and control of multi- ngered hands need information about the points of contact with a grasped object as well as the normal of the surface in the contact point. With no image processing, this information is gained from tactile sensor arrays, multidimensional force/torque sensors or a priori knowledge. This paper presents a method for those cases, when no good quality sensors are present or measurements are to be improved by sensor fusion. An algorithm is developed to determine the contact points and inherently the surface normal from only joint angle sensors and a geometric description of the ngertip in the 3D case. This is done by observing the constrained motion of fingers securely grasping an object.

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A novel two-degree-of-freedom tactile display reproduces the sensations of sliding contact and incipient slip through the rotation of a ball positioned under the user’s fingertip. A pair of motor-driven wheels actuates the ball via contact friction. Mechanical performance requirements are used to define the dimensions and construction method of the device. Kinematic analysis shows that the drive wheel angles and their contact locations with the ball must be carefully selected in order to accurately control the axis of rotation and speed of the ball. However, psychophysical experiments indicate that some kinematic error is tolerable; errors of up to 20 ◦ in slip angle and 30 % of a nominal velocity may be applied without detection from an average user. The lightweight, modular tactile display was attached to a multi-degree-of-freedom kinesthetic interface and used to display virtual environments with slip. Experimental results demonstrate that users complete a virtual paper manipulation task with lower applied forces using combined slip and force feedback in comparison with conventional force feedback alone. Categories and Subject Descriptors: H.1.2 [Models and Principles]: User/Machine Systems—Human information processing;