This paper proposes a method to calculate the largest Regular Dextrous Workspace (RDW) of some types of threerevolute orthogonal manipulators that have at least one of their DH parameters equal to zero. Then a new performance index based on the RDW is introduced, the isocontours of this index are plotted in the parameter space of the interesting types of manipulators and finally an inspection o...

Two optimization studies on the design of a three degree of freedom translational parallel platform are conducted and the results are compared. The objective function of the rst study maximizes total volume of the manipulator workspace without regard to the quality of the workspace. The second study optimizes the total volume of well conditioned workspace by maximizing a global condition index....

Let S be a planar n-point set. Classically, one can find the Voronoi diagram VD(S) for S in O(n log n) time and O(n) space. We study the situation when the available workspace is limited: for s ∈ {1, . . . , n}, an s-workspace algorithm has read-only access to an input array with the points from S in arbitrary order, and it may use only O(s) additional words of Θ(log n) bits for reading and wri...

Quantitative measures of the space an individual can reach is essential for tracking the progression of a disease and the effects of therapeutic intervention. The reachable workspace can be used to track an individuals’ ability to perform activities of daily living, such as feeding and grooming. There are few methods for quantifying upper limb performance, none of which are able to generate a r...

Using an audio-only diagraming tool, sixteen pairs of sighted individuals collaborated in a workspace where they used sound as the only means to communicate with each other and to access and edit shared entity-relationship diagrams. We examined the effects of the means for delivering audio to such a workspace – using headphones or speakers – on pairs’ workspace awareness. Results showed that pa...

Bimanual manipulation of objects is receiving a lot of attention nowadays, but there is few literature addressing the design of the arms configuration. In this paper, we propose a way to analyze the relative positioning of two redundant arms, both equipped with spherical wrists, in order to obtain the best common workspace for grasping purposes. Considering the geometry of a robot with a spheri...

The apparent gravity force acting on the end-effector of an haptic device depends on its position inside the workspace. This thesis presents an offline recursive algorithm to automatically estimate the required gravity compensation terms to be applied to the end-effector at a given set of positions, corresponding to the vertices of a cubic grid contained into the device workspace. Online gravit...

We consider the estimation of the post-failure workspace of two two-link serial robots where the free-swinging failure of one robot’s last joint is handled by having the functional robot grasp the final link of the broken robot. We present an algorithm for finding the optimal placement of such synergistic robot arms and the optimal grasp point on the final link of the broken robot. To determine...

The workspace topologies of a family of 3-revolute (3R) positioning manipulators are enumerated. The workspace is characterized in a half-cross section by the singular curves. The workspace topology is defined by the number of cusps that appear on these singular curves. The design parameters space is shown to be divided into five domains where all manipulators have the same number of cusps. Eac...

In this paper, we introduce new performance indices to characterize the workspace of reconfigurable hyper-redundant robotic arms. These indices are then used to analyze the workspace of a type of hyper-redundant robotic arm using as modules lower mobility parallel platforms. The modules of the reconfigurable robotic arm are the three-legged translational universal–prismatic–universal (UPU) and ...