This paper presents the mechanical-workings and gripping performance characteristics of a vacuum-based robotic gripper. The gripper uses multiple ports with attached commercial suction cups to grasp objects from a variety of directions using suction power. The valves remain closed until opened by a hinge-based mechanism, in order to eliminate vacuum leakage. The ability for the valves to be act...

In space application, it is of great interest the development of autonomous or semi-autonomous robotic devices that can substitute the astronauts in routine operations in order to free them from repetitive tasks and reduce mission costs. In this work, an experimental setup based on a 6 degrees of freedom (dof) manipulator with a 3 dof gripper designed for a possible application within PaT, the ...

Although image-based visual servoing provides superior performance in many vision-based robotic applications, it reveals fatal limitations when initial pose discrepancy is large. The feature points may leave the camera’s field of view, and also, the robot may not converge to the goal configuration. In this paper, a novel approach is proposed to resolve these limitations by planning trajectories...

In space applications, it is conceivable that part of the robotic activities could involve the grasp and/or manipulation of free-floating objects in absence of gravity. In this case, synchronous application of contacts seems to represent a basic feature in order to efficiently grasp the floating items. In this sense, an additional difficulty is that objects may have irregular shape and/or be no...

This paper proposes the development of an automatic fruit harvesting system by combining a low cost stereovision camera and a robotic arm placed in the gripper tool. The stereovision camera is used to estimate the size, distance and position of the fruits whereas the robotic arm is used to mechanically pickup the fruits. The low cost stereovision system has been tested in laboratory conditions ...

Dedicated fixtures are costly and inflexible. The goal of fixtureless assembly is to replace assembly fixtures with sensor-guided robots equipped with flexible grippers. This, in turn, requires the development of automated grasp planning strategies, and grippers with the flexibility to pick up and immobilize a wide range a object sizes and shapes. In this paper, an efficient grasp planning meth...

This article presents the design of a variable stiffness, soft, three-fingered dexterous gripper. The gripper uses two designs of McKibben muscles. Extensor muscles that increase in length when pressurized are used to form the fingers of the gripper. Contractor muscles that decrease in length when pressurized are then used to apply forces to the fingers through tendons, which cause flexion and ...

During robotic assembly of flexible payloads, gravity and inertial forces acting on these payloads may induce both static shape deformation and vibration of the thin-walled payloads. Static deformations, which arise from deformation of the part due to its own weight under the influence of gravity, lead to misalignment of mating points of the part. Unwanted vibrations, arising from inertial forc...

This paper discusses a fuzzy logic control system designed to determine, regulate and maintain the amount of suction needed by a robotic gripper system to perform reliable limp material manipulation. A neuro-fuzzy approach is followed to determine the amount of desired suction (depending on experimentally derived data and plant characteristics). A knowledge-based valve controller is then design...

This paper addresses the problem of grasping and manipulating three-dimensional objects with a reconngurable gripper equipped with two parallel plates whose distance can be adjusted by a computer-controlled actuator. The bottom plate is a bare plane, and the top one carries a rectangular grid of actuated pins that can translate in discrete increments under computer control. We propose to use th...