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...

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Thi s puper eztcn,ds the caging theory of R i m o n and Bluke [ill for. orre-parameter two-finger grippers t o orwparame tar three-finger grippers. T h e caging theory describes lroui the f ingers of a robot gripper can be placed uroumd u n object so tha t it cannot escape. A s the fiingers close f r o m such a configuration, the f reedom of the object t o move is gradually restricted, unti l ,...

We present a planner for a robot to keep an object stable under a sequence of external forces. We assume a robot with multiple manipulators, with a gripper at the end of each manipulator. We make two key contributions: First, given an external force, we propose a method to check the feasibility of gripper placements on the object to resist the force. This method takes into account both the mani...

ANALYSIS OF SPHERICAL FIVE-BAR HINGED MANIPULATOR WITH TWO DEGREES OF FREEDOM AND DWELLS OF OUTPUT LINK. N. Davitashvili. “Problems of Mechanics”. Tbilisi, 2015, No 1(58), pp. 5-11, (Engl.). Is stated the kinematic study of spherical five-bar manipulator with two degrees of freedom. Are determined the positions, velocities and accelerations of output links, their points and gripper. The manipul...

The paper presents an optimal synthesis of overconstrained linkages, based on the factorization of rational curves contained in Study’s quadric. The group of Euclidean displacements is embedded in a affine space where a metric between motions based on the homogeneous mass distribution of the end effector is used to evolve the curves such that they are fitted to a set of target poses. In the end...