Stability and control of rotors at high advance ratio are considered. Stability of teetering, articulated, and gimbaled hub types is considered with a simple flapping blade analysis. Rotor control in autorotation for teetering and articulated hub types is examined in more detail for a compound helicopter (rotor and fixed wing) using the comprehensive analysis CAMRAD II. Autorotation is found to...

Challenges for the controlled flight of a robotic insect are due to the inherent instability of the system, complex fluid-structure interactions, and the general lack of a complete system model. In this paper, we propose theoretical models of the system based on the limited information available from previous work and a comprehensive flight controller. The modular flight controller is derived f...

Flow visualisations are essential to better understand the unsteady aerodynamics of flapping wing flight. The issues inherent to animal experiments, such as poor controllability and unnatural flapping when tethered, can be avoided by using robotic flyers. Such an approach holds a promise for a more systematic and repeatable methodology for flow visualisation, through a better controlled flight....

While the biological flyers often showcase high deformed wing structures, the effects of flexibility on the flapping wing aerodynamics remain inadequately understood. A major challenge in the study of flexible flapping wings is that the resulting wing motion is an outcome of a dynamic balance between the structural dynamics of the wing and the unsteady aerodynamics. Since the effective angle of...

Flapping flight is ubiquitous in Nature, yet cilia and flagella, not wings, prevail in the world of micro-organisms. This paper addresses this dichotomy. We investigate experimentally the dynamics of a wing, flapped up and down and free to move horizontally. The wing begins to move forward spontaneously as a critical frequency is exceeded, indicating that ‘flapping flight’ occurs as a symmetry-...

The inherent stability of two-dimensional motion when hovering using beating wings that have a passive feathering is compared with rotary flapping motion. the determined by bending elasticity, which expressed spring at wing root. torsional damper and values were minimizing necessary power in present analysis. Unlike motion, do not pitch/roll damping. A flying robot requires quicker flight contr...

We examine the fluid-mechanical interactions that occur between arrays of flapping wings when operating in close proximity at a moderate Reynolds number (Re≈100-1000). Pairs of flapping wings are oscillated sinusoidally at frequency f, amplitude θ_{M}, phase offset ϕ, and wing separation distance D^{*}, and outflow speed v^{*} is measured. At a fixed separation distance, v^{*} is sensitive to b...

A flight-dynamics oriented simulation model of a flapping-wing Micro Air Vehicle (MAV) has been developed. This concept is based on flapping flight performed in nature by insects or hummingbirds. An optimization of the flapping kinematics of the wing has been led, in order to maximize the mean lift and thus the payload. A neural network has been designed to reproduce the function shape of the w...

the aim of this study was to investigate the effects of preslaughter shackling durations on some blood parameters, breast and thigh meat quality traits, and muscle metabolites in broilers. the effects of shackling were determined in a group of ross 308 broilers (240 birds) aged 42 days. four shackling treatments were used in experimental tests: shackling of broilers for 10 (group g10; as contro...

Flapping wing vehicles, or ornithopters, have proven difficult to control due to the unsteady flow generated by the high-speed flapping surfaces. To-date, research has focused on computational models from which fixed flapping strokes are optimized. These strokes are then fixed and executed open-loop in practice with flapping speed as the primary control output for climb and descent. This paper ...