In this experiment, we consider the nonlinear control of a robotic arm with joint flexibility. The specific mechanism under investigation is an attachment to rotary Quanser experimental setup. Flexibility is attained by attaching the link to the motor shaft using a pair of springs. There is some discretion in choosing the joint stiffness as there are different locations that the springs can be ...

Rats and other whiskered mammals are capable of making sophisticated sensory discriminations using tactile signals from their facial whiskers (vibrissae). As part of a programme of work to develop biomimetic technologies for vibrissal sensing, including whiskered robots, we are devising algorithms for the fast extraction of object parameters from whisker deflection data. Previous work has demon...

In a trochoidal-type machine, the rotor and chamber will be in direct contact when apex seals arc removed. The reliability and efficiency of the machine will depend on the magnitude of these contact forces. In this paper, a finite element model that simulates the planetary rotation of a rotor inside a chamber is developed. The model is then used to analyze contact forces between rotor and chamb...

objectives: the aim of this study was to assess and compare the characteristics of commonly used initial archwires by their load deflection graphs. materials and methods : this study tested three wire designs namely copper nickel titanium (cnt), nickel titanium (niti), and multi-strand niti (msnt) archwires engaged in passive self-ligating (psl) brackets, active self-ligating (asl) brackets or ...

Mechanoreceptors involved in the escape jumping evoked by hindwing stimulation have been investigated in the field cricket Gryllus bimaculatus. By partial ablation of the hindwing, we found that a mechanosensory system relevant to the escape behaviour was localized on specific veins of the hindwing tip. Scanning electron microscopy revealed three types of mechanoreceptive sensillae on the corre...

The paper investigates the use of compensating balancing sleeves positioned at shaft’s end for high-speed flexible shafts. sleeve is a new arrangement that creates pure moment with virtually zero radial reaction forces. For comparison purposes, experimental results from previous research are used to benchmark performance and demonstrate benefits newly proposed topology. configuration commensura...

The role of facial vibrissae (whiskers) in the behavior of terrestrial mammals is principally as a supplement or substitute for short-distance vision. Each whisker in the array functions as a mechanical transducer, conveying forces applied along the shaft to mechanoreceptors in the follicle at the whisker base. Subsequent processing of mechanoreceptor output in the trigeminal nucleus and somato...

The effect of the temperature variation on a unimorph piezoelectric cantilever is studied. Its influences on the thermal expansion, the piezoelectric constant, the transient part and the creep are experimentally analyzed. Afterwards, a H∞ controller is synthesized in order to reject the thermal disturbance and to reach performances required in micromanipulation. Finally, the closed-loop experim...

this article studied static deflection, natural frequency and nonlinear vibration of a clamped-clamped microbeam under discontinues electrostatic actuation. the electrostatic actuation was induced by applying ac-dc voltage between the microbeam and electrode plate. in contrast to previous works, it was assumed that length of the electrode plate was smaller than that of the microbeam. in additio...

background:   although intramedullary nailing (imn) is an established and accepted operative treatment for femoral shaft fracture in patients younger than 60, there is a lack of data on the results of this treatment on those over 60. the purpose of this study was to determine if the outcome of imn for femoral shaft fracture in elderly patients is also acceptable. particular challenges in this g...