The nonholonomy exhibited by kinematic systems consisting of bodies rolling on top of each other can be used to the purpose of building dexterous mechanisms with a minimum hardware complication. Such desirable an engineering feature can be fully exploited, however, only if the capability of planning and controlling rolling motions of arbitrary objects is achieved. In this paper we present recen...

This paper describes a method to solve the direct kinematics of a generic Stewart-Gough manipulators. The method is formulated in terms of a search in the space of rigid body transformations. The underlying idea is that the solutions of the direct kinematics can be obtained by moving the end-effector body according rotations and translations and accounting for the rigidity conditions. The paper...

Contact state information is indispensable for performing skillful tasks in which an end-effector should be in contact with the environment. In previous work, the authors introduced the concept of a pseudo contact point that is useful for tasks involving contact as one expression of the contact state. In this paper, an extended definition of the pseudo contact point is proposed. The pseudo cont...

This paper describes guidelines for the design of grippers for use in modular manufacturing workcells. Gripper design is an important and often overlooked aspect of the design of a complete assembly system. Here we present guidelines which can be applied to a wide variety of grippers and are divided into two major categories: Those that improve system throughput and those that increase system r...

Rehabilitation robot positively improves walking ability of patients with gait disorders. In this paper, our discussion focuses on exoskeleton robot and end-effector robot. The purpose of this study was to compare the training methods and gait biomechanics on subjects when training on rehabilitation robots.

A small-scale flexure-based gripper was designed for manipulation tasks requiring precision position and force control. The gripper is actuated by a piezoelectric ceramic stack actuator and utilizes strain gages to measure both the gripping force and displacement. The position and force bandwidths were designed for ten Hertz and one hundred Hertz, respectively, in order to afford human-based te...

Parallel manipulators have a specific mechanical architecture where all the links are connected both at the base and at the gripper of the robot. By changing the lengths of these links we are able to control the position 1 of the gripper. In general for a given set of links lengths there is only one position for the gripper. But it may be suspected that in some In this paper position means posi...

In thzs paper, we focus on the problem of controllang a manzpulator so as to track a desired object trajectory, whzle guaranteeang that contact forces comply wath contact constraants (frzctzon bounds, etc ). When dealing wath kznematzcally defectawe systems, zt as not possable an general to asszgn arbatmry trajectoraes of ob.fect motaons and contact forces. To understand what restrzctaons poszt...

Abst-ract constraint. A static grasp occurs, for example, if a cube is grasped in a frictional parallel-jaw gripper, since the frictional forces must be included to verify stability. A quasi-static grasp might correspond to pushing a sofa across the floor-the sofa retains contact with the effector to balance the forces of sliding This paper' describes some preliminary work on dynamic manipulati...