Abstract. Goal.The stability of elastic elements in a deformed state with initial imperfections the structural form for truss rigid and nodes was studied. Method. The operation compressed trusses welded joints is most accurately described by model which one support other has resistance conditions. According to methodology parameters, analytical method from solution differential equation rod sta...

Many animals use catapult mechanisms to produce extremely rapid movements for escape or prey capture, resulting in power outputs far beyond the limits of muscle. In these catapults, muscle contraction loads elastic structures, which then recoil to release the stored energy extremely rapidly. Many arthropods employ anatomical 'catch mechanisms' to lock the joint in place during the loading perio...

Metal-composite joints connecting conventional steel to an advanced fiber composite are an attractive structural system for hybrid ship hulls as well as aircraft frames. The objective of this study is to analyze the size effect on the strength of hybrid joints numerically, theoretically and experimentally. In the numerical analysis, linear elastic continuum elements are used for the composite a...

We present some feedback control techniques recently developed for the exact solution of t rajectory tracking problems for manipulators with flexible elements. Two classes are considered: i) robots with rigid links but with elastic transmissions, in which flexibility is concentrated at the joints, and ii) robots with lightweight and/or long arms, where flexibility is distributed along the links...

A proportional-derivative (PD) control with on-line gravity compensation is proposed for regulation tasks of robot manipulators with elastic joints. The work extends a previous PD control with constant gravity compensation at the desired configuration. The control law requires measuring only position and velocity on the motor side of the elastic joints, while the on-line gravity compensation to...

We consider some theoretical aspects of the control problem for rigid link robots having some joints rigid and some with non-negligible elasticity. We start from the reduced model of robots with all joints elastic introduced by Spong, which is linearizable by static feedback. For the mixed rigid/elastic joint case, we give structural necessary and sufficient conditions for input—output decoupli...

background and objectives : examination of cartilage repair in animal work is dependent upon the thickness and radius of the induced impalement.  full-thickness defects with a radius of 3 mm have been commonly used in animal studies to evaluate new procedures designed to improve the quality of articular cartilage repair. the aim of the present study was to define the biomechanical characteristi...