The weighted maximal planar graph (WMPG) problem seeks to find a subgraph from a given weighted complete graph such that the subgraph is planar—it can be embedded on the plane without any arcs intersecting. The subgraph is maximal—no additional arc can be added to the subgraph without destroying its planarity and it also has the maximal sum of arc weights. In this paper, the main objective is t...

Accurate dynamic models of human hands grasping haptic devices can help to inform stability analyses, control algorithms, device design, and technology development efforts. The current study develops and tests a lumped second-order dynamic model for nine subjects holding a haptic knob in a simple pinch grasp. Results include steadily increasing damping and stiffness parameters with increasing g...

This paper focuses on the problem of force-feedback for the human-operator hand when manipulating virtual objects. We propose a method for the computation of feedback-forces that have to be applied on each individual phalanx and nger of the human hand in order to display pertinent, kinesthetic information about static or dynamic characteristics of objects present in the virtual scene. External ...

Reaching and grasping in primates depend on the coordination of neural activity in large frontoparietal ensembles. Here we demonstrate that primates can learn to reach and grasp virtual objects by controlling a robot arm through a closed-loop brain-machine interface (BMIc) that uses multiple mathematical models to extract several motor parameters (i.e., hand position, velocity, gripping force, ...

Grasping and manipulation skills are key aspects for service robots. We present our initial work on the dynamic grasp acquisition (DGA) problem, which is characterized by a large relative velocity between the palm of the hand and the object at the time the fingers begin closing to form the grasp. These kinds of problems are particularly demanding for the hardware and software systems, and so we...

It is proposed an optimization-based controller that reactively adapt the position of the end effectors in cooperative robot systems or fingers, in case of robotic hands. The proposed optimization-based controller uses the force tracking error for each robot, allowing to reactively correct the applied force, thus guaranteeing a stable grasp. Force information is used to determine the modificati...

A stable grasp can only be achieved with multi-fingered grippers. The required task for the robots has become more complicated such as handling of objects with various properties e.g. material, size, mass etc. and the physical interaction between the finger and an object has also become complicated e.g. grasping with slippage, finger gait ..... etc. This paper focuses on enhancing the grasping ...

Skilled grasp is a sensorimotor process requiring the brain to extract sensory cues from the environment to shape a motor command. Although a large body of literature has focused on which brain areas either integrate the visual object's properties or control the motor output, it is still unclear how grasp-related information is transferred from one area to another. Understanding interactions be...