Articulated mechanical systems with multiple joints possess multiple degrees-of-freedom which are often not required for performing typical low-dimensional manipulation tasks. These excessive degrees of freedom then need to be reduced by application of constraints, either actively by suitable control or passively in hardware, prior to performance of the task. Our interest is in creating articul...

The manipulation of objects held in a robotic hand or gripper is accompanied by events such as making and breaking contact and slippage, between the fingertips and the grasped object and between the grasped object and external surfaces. Humans can distinguish among such events, in part, because they excite the various mechanoreceptors in the hands differently. As part of an effort to provide ro...

A new method for mitigating unexpected impact of a redundant manipulator with an object in its environment is presented. Kinematic constraints are utilized with the recently developed method known as Full Space Parameterization (FSP). System performance criteria and constraints are changed at impact to return the end effector to the point of impact and halt the arm. Since large joint accelerati...

This paper presents the comparison between serial and parallel manipulators. Day by day, the applications of the parallel manipulator in various field is become apparent and with a rapid rate utilized in precise manufacturing, medical science and in space exploration equipments. A parallel manipulator can be defined as a closed loop kinematic chain mechanism whose end effector is linked to the ...

Firstly, model of a 6-DOF articulate manipulator was set up in MATLAB, then kinematic analysis and simulation of this manipulator was studied. Secondly, it was found to acquire the desired configuration within the given time limits with irregular motion pattern along the end-effector path. Simulation results showed that the manipulator was capable of light material handling and transfer in an a...

A s serial robots parallel manipulator may be in a singular configuration. In these configurations the inverse jacobian matrix is singular and the end-effector may move although the articular velocities are equal to zero. The determination of the loci of these singular configurations is an important problem because in such configuration the articular forces may go to infinity and yield importan...

We investigate robotic assistants for dressing that can anticipate the motion of the person who is being helped. To this end, we use reinforcement learning to create models of human behavior during assistance with dressing. To explore this kind of interaction, we assume that the robot presents an open sleeve of a hospital gown to a person, and that the person moves their arm into the sleeve. Th...

Vision feedback control loop techniques are efficient for a great class of applications but they come up against difficulties when the initial and desired positions of the camera are distant. In this paper we propose a new approach to resolve these difficulties by planning trajectories in the image. Constraints such that the object remains in the camera field of view can thus be taken into acco...

Deep reinforcement learning yields great results for a large array of problems, but models are generally retrained anew for each new problem to be solved. Prior learning and knowledge are difficult to incorporate when training new models, requiring increasingly longer training as problems become more complex. This is especially problematic for problems with sparse rewards. We provide a solution...

A hybrid control scheme based on adaptive visual servoing and direct force control is proposed for robot manipulators to perform interaction tasks on smooth surfaces. The camera parameters, as well as the constraint surface, are considered to be uncertain. A fixed camera with optical axis non-perpendicular to the robot workspace is used for position control, while a force sensor mounted on the ...