Finger design automation for industrial robot grippers: A review <s> Virtual Experiment <s> Grasp and manipulation planning of slippery objects often relies on the 'lform'closure" grasp, which can he maintained regardless of the external force applied to the object. Despite its importance, a quantita- tive test ,for form closure valid for any number of contact points is not availuhle. The primary contribution of this paper is the introduction of such a test formulated as a lineor program, of which the optimal objective value provides a measure of how far a grasp is from losing ,form closure. While the test is formulated for frictionless grasps, we discuss how it can be modified to identify grasps with 'yrictional fortn closure." I. IX'l'IiODUClTOX <s> BIB001 </s> Finger design automation for industrial robot grippers: A review <s> Virtual Experiment <s> We develop a geometric framework for the stability analysis of multifingered grasps and propose a measure of grasp stability for arbitrary perturbations and loading conditions. The measure requires a choice of metric on the group of rigid body displacements. We show that although the stability of a grasp itself does not depend on the choice of metric, comparison of the stability of different grasps depends on the metric. Finally, we provide some insight into the choice of metrics for stability analysis. <s> BIB002 </s> Finger design automation for industrial robot grippers: A review <s> Virtual Experiment <s> An algorithm for automatically generating a common jaw design and planning grasps for a given set of polyhedral objects is presented. The algorithm is suitable for a parallel-jaw gripper equipped with three cylindrical fingers. The common jaw design eliminates the need for custom made grippers and tool changing. The proposed jaw configuration and planning approach reduces the search associated with locating the finger contacts from six degrees-of-freedom to one degree-of-freedom. Closed-form algorithms for checking force closure and for predicting jamming are developed. Three quality metrics are introduced to improve the quality of the planned grasps. The first is a measure of the sensitivity of the grasp to errors between the actual and planned finger locations. The second is a measure of the efficiency of the grasp in terms of the contact forces. The third is a measure of the dependence of force closure on friction. These quality metrics are not restricted to cylindrical fingers and can be applied to n finger grasps. Running on a standard PC, the algorithm generated a solution in less than five minutes for a set of five objects with a total of 456 triangular facets. © 2003 Wiley Periodicals, Inc. <s> BIB003 </s> Finger design automation for industrial robot grippers: A review <s> Virtual Experiment <s> This paper presents an iterative procedure to find locally optimum force-closure grasps on 3D objects, with or without friction and with any number of fingers. The object surface is discretized in a cloud of points, so the approach is applicable to objects with any arbitrary shape. The approach finds an initial force-closure grasp that is then iteratively improved through an oriented search procedure. The grasp quality is measured considering the largest perturbation wrench that the grasp can resist with independence of the direction of perturbation. The efficiency of the algorithm is illustrated through numerical examples. <s> BIB004 </s> Finger design automation for industrial robot grippers: A review <s> Virtual Experiment <s> This paper presents a new method for solving the grasp optimization problem by a multi-finger robotic hand; this method allows gripping an object using three articulated fingers, in order to manipulate it later. Because of the large number of operations and the high computation time, online grasp has not yet been reported. In this study, we propose a method that is able to provide an optimized initial grasp in a short time before online manipulation. <s> BIB005 </s> Finger design automation for industrial robot grippers: A review <s> Virtual Experiment <s> This paper presents an analysis of object grasping with a multifingered robot hand. Uncertainties on the contact orientation and location are investigated and taken into account to find a new grasp quality measure. This new metric allows to evaluate the controllability of the system and find the Reachable Wrench Space under Uncertainties, a new set introduced in this paper. It includes all the wrenches a grasp can apply whatever the uncertainty is, and gives information about the robustness of the grasp relative to disturbances. Two algorithms are proposed to estimate this new set. Several study cases are presented and tested in simulation to illustrate the new quality metric. <s> BIB006 </s> Finger design automation for industrial robot grippers: A review <s> Virtual Experiment <s> In this paper, we suggest gripper quality metrics that indicate the performance of a gripper given an object CAD model and a task description. Those, we argue, can be used in the design and selection of an appropriate gripper when the task is known. We present three different gripper metrics that to some degree build on existing grasp quality metrics and demonstrate these on a selection of parallel jaw grippers. We furthermore demonstrate the performance of the metrics in three different industrial task contexts. <s> BIB007 </s> Finger design automation for industrial robot grippers: A review <s> Virtual Experiment <s> This paper proposes a task-oriented grasp quality metric based on distribution of task disturbance, which could be used to search for a grasp that covers the most significant part of the disturbance distribution. Rather than using a uniformly distributed task wrench space, this paper models a manipulation task with a non-parametric statistical distribution model built from the disturbance data captured during the task demonstrations. The grasp resulting from maximizing the proposed grasp quality criterion is prone to increasing the coverage of most frequent disturbances. To reduce the computational complexity of the search in a high-dimensional robotic hand configuration space, as well as to avoid the correspondence problem, the candidate grasps are computed from a reduced configuration space that is confined by a set of given thumb placements and thumb directions. The proposed approach has been tested both in simulation and on a real robotic system. In simulation, the approach was validated with a Barrett hand and a Shadow hand in several manipulation tasks. Experiments on a physical robotic platform verified the consistency between the proposed grasp metric and the success rate. <s> BIB008
Virtual experiments are done using virtual workpiece models instead of physical ones. This type of experiment is very popular in literature due to its simplicity and low cost. Using publicly available grasp simulators have helped many researchers to verify their approach virtually BIB005 BIB008 . Studies using virtual experiments usually verified their methods on examples BIB001 BIB002 BIB003 BIB004 BIB006 BIB007 and only a few research compared their proposed approach with others  Carpin, 2015a, 2015b) . As mentioned in section 3.1.1, the main reason of limited comparison in literature is the reluctance of the authors to publish the implemented methods. Publicly available grasp simulators have enhanced the finger design research area so the user can fully simulate and control the workcell environment and its attributes. The users have the capability of performing a large number of experiments without having access to costly robotic hardware. While the currently available virtual experiments are easy to carry out, studies have shown that the results of virtual experiments noticeably differ from physical experiments. As a result these experiments should only be used for preliminary and conceptual checks on the feasibility of the designed fingers.