OBJECTIVES The aim of the current study was to analyse the effects of posterior cruciate ligament (PCL) deficiency on forces of the posterolateral corner structure and on tibiofemoral (TF) and patellofemoral (PF) contact force under dynamic-loading conditions. METHODS A subject-specific knee model was validated using a passive flexion experiment, electromyography data, muscle activation, and ...

The successful execution of any contact task fundamentally requires the application of wrenches (forces and moments) consistent with the task. We develop an algorithm for computing the entire set of wrenches consistent with achieving a given augmented contact mode (e.g., sliding at contact 1, rolling at contact 2, and approaching potential contact 3) for one fixed and one moving part in the plane.

The work described in this paper addresses the problem of determination of the appropriate distribution of forces between the fingers of a multifingered gripper grasping an object. The system is statically indeterminate and an optimal solution for this problem is desired for force control. A fast and efficient sub-optimal method for computing the grasping forces is presented. This method is bas...

The efficiency of the automatic execution of complex assembly tasks can be enhanced by the identification of the contact state. In this paper we derive a new method for testing a hypothesized contact state using force sensing in the presence of sensing and control uncertainty. The hypothesized contact state is represented as a collection of elementary contacts. The feasibility of the elementary...

To be successful at manipulating objects one needs to apply simultaneously well controlled movements and contact forces. We present a computational theory of how the brain may successfully generate a vast spectrum of interactive behaviors by combining two independent processes. One process is competent to control movements in free space and the other is competent to control contact forces again...

“We are without allies amongst the Iraqi populace, including those who have benefited from the ouster of Saddam. . . . Across Baghdad, Latifiyah, Mahmudiyah, Salman Pak, Baqubah, Balad, Taji, Baiji, Ramadi, and just about everywhere else you can name, the people absolutely hate us. . . . The Iraqi people have not bought into what the Americans are selling, and no amount of military activity is ...

The theory of contact mechanics deals with stresses and deformations which arise when the surfaces of two solid bodies are brought into contact. In elastic deformation contact occurs over a finite area. A regular method for determining the dimensions of this area is Hertz Contact Model. Appearance of atomic force microscope results in introduction of Contact ...

The development of legged robots for complex environments requires controllers that guarantee both high tracking performance and compliance with the environment. More specifically the control of the contact interaction with the environment is of crucial importance to ensure stable, robust and safe motions. In this contribution we develop an inverse-dynamics controller for floating-base robots u...

The paper considers the behavior of redundant manipulators which collide with an obstacle and the obstacle avoidance after the collision. Without changing the motion of the end-effector, the reconfiguration of the manipulator into a collision-free configuration can be done only by utilizing the self-motion of the manipulator. In the paper some motion controllers are analyzed which minimize the ...