This paper deals with the problem of synthesis of stable grasp by multi-fingered hands. First, a mathematical description of the problem is formulated. The grasp to be synthesized should satisfy equilibrium conditions and unilateral frictional constraints. It should also be stable against disturbances applied to the object. Two types of stability conditions, contact stability and Lyapunov stabi...

The significance of the seismic rotational components have been overlooked in the seismic evaluation of structural behavior. As researchers have measured seismic components more accurately using sensitive rotational velocity sensor, it was observed that the magnitude of rotational components is considerable and could not be neglected. Hence, some parts of seismic damage or failure of structures...

In the Northridge and Kobe earthquakes, brittle failure of welded beam-to-column connections was observed in steel structures. So, bolted were considered as an alternative to these kinds connections. Extended end-plate con-nection is one most commonly used structure. this article, behavior sloped extended studied. Finite element method investigate connection by ABAQUS software. The main aim stu...

Although the principle of using x-rays for diagnostic imaging has been known for a long time, there is still a lot of research and improvements going on in the field. One recent addition to the neuro-vascular imaging system—used for visualizing blood vessels in the brain and guidance of interventions—is 3D rotational angiography (3D-RA). Using 3D-RA, it is possible to view the vessel tree in 3D...

A novel pure rotary actuator with a double-layer flexible mechanism (RA-DFM), which is driven by single piezoelectric ceramic in the lower and generates rotational motion upper mechanism, proposed this paper. The output of successively amplified using an enhanced double Scott–Russell two lever-type mechanisms to obtain large rotation range. static, kinematic dynamic properties RA-DFM are numeri...

optimization of structures for minimum weight has become important in the recent designs. in this study, a genetic optimization algorithm for weight minimization of steel frames has been used. the genetic algorithm is an optimization and search technique based on the principles of genetics and natural selection. constraints regarding material strength and serviceability are taken from “aisc cod...

the present study assesses the seismic performance of steel moment resisting frames (smfs) retrofitted with different bracing systems. two structural configurations were utilized: ordinary concentrically braces (ocbfs), buckling-restrained braces (brbfs). a 7-story and 18-story steel perimeter smfs were designed with insufficient lateral stiffness to satisfy code drift limitations in high seism...

in this study, friction stir spot welding (fssw) is applied to join the tial6v4 titanium alloy with 1.5 mm thickness and then the effect of rotational speed and tool dwell time on microstructure and mechanical properties is investigated. in this regard, the speed of the tool rotation was considered as 800, 1000, and 1200 rpm, as well as the tool dwell time was set at 7 and 12s. microstructural ...

it is well-known that the behavior of soil-structure systems can be well described using a limited number of non-dimensional parameters. this is the outcome of researches based on the premise that the foundation is bonded to the ground. here, it is shown the concept can be extended to systems with foundation uplift. a set of non-dimensional parameters are introduced which controls the main feat...