Robotic devices, such as rovers and autonomous spacecraft, have been successfully controlled by plan execution systems that use plans with temporal flexibility to dynamically adapt to temporal disturbances. To date these execution systems apply to discrete systems that abstract away the detailed dynamic constraints of the controlled device. To control dynamic, under-actuated devices, such as ag...

This paper presents the first prototype of a magnetic resonance imaging (MRI) compatible piezoelectric actuated robot integrated with a high-resolution fiber optic sensor for prostate brachytherapy with real-time in situ needle steering capability in 3T MRI. The 6-degrees-of-freedom (DOF) robot consists of a modular 3-DOF needle driver with fiducial tracking frame and a 3-DOF actuated Cartesian...

A capacitive micromachined ultrasonic transducer (CMUT) due to many benefits is being considered as an imaging and therapeutic technology recently. The critical challenge stabilize the system beyond pull-in voltage considering imposed perturbations. CMUT system, on other hand, has a low range of movement it intrinsically unstable, which can result in phenomenon. Consequently, order use systems ...

SemiQuad is walking robot prototype with a platform and two two-link legs. Thus, it is five-link mechanism. Front leg models identical motions of two quadruped’s front legs, rear leg models identical motions of two quadruped’s rear legs. We call this robot also as “virtual” quadruped. The mechanism is driven by four DC motors. Its control system comprises a computer, hardware servo-systems and ...

BACKGROUND Image-guided endovascular interventions have gained increasing popularity in clinical practice, and magnetic resonance imaging (MRI) is emerging as an attractive alternative to X-ray fluoroscopy for guiding such interventions. Steering catheters by remote control under MRI guidance offers unique challenges and opportunities. METHODS In this review, the benefits and limitations of M...

background: over the past several years, mammals have been successfully cloned by either the splitting of an early stage embryo or nuclear transfer of adult somatic cells (nt) into oocytes. although it has been 15 years since the generation of the first cloned mammals from somatic cells by nt, the success rate for producing live offspring by this technique is low regardless of the cell type and...

friction is a nonlinear phenomenon which has destructive effects on performance of control systems. to obviate these effects, friction compensation is an effectual solution. in this paper, an adaptive technique is proposed in order to eliminate limit cycles as one of the undesired behaviors due to presence of friction in control systems which happen frequently. the proposed approach works for n...