Angular maneuvering scheme along with standard flight operations such as taking-off, landing and hovering is proposed for a quadcopter with indoor or outdoor flying capabilities. This is achieved by simultaneously controlling the speed of the four rotors in order for the quadcopter to attain the correct orientation. The total thrust is determined using the inputs of altitude, pitch and roll ang...

Speed and position control systems for marine vehicles have been subject to an increased focus with respect to performance and safety. An example is represented by drilling operations performed with semi submersible rigs where the control of position and heading requires high accuracy. Drifting from the well position could cause severe damage to equipment and environment. Also, the use of under...

During the past decade, polymer nanocomposites have emerged relatively as a new and rapidly developing class of composite materials and attracted considerable investment in research and development worldwide.Direct machining of polymers can be an option for personalized products and for manufacturing product samples. To obtain high quality products and reduce machining costs, it is very importa...

b number of arc segments within curve CF thrust coefficient CF;w weighted thrust coefficient Cx nozzle length-weight coefficient E numerical error k turbulent kinetic energy, m s−2 L total contour axial length, m Ma Mach number P static pressure, Pa r radius, m TW thrust-to-weight ratio x horizontal distance, m y vertical distance, m ε turbulent dissipation rate, m s−3 θ angle, deg ω specific d...

A torsional-type thrust stand has been designed and built to test Pulsed Plasma Thrusters (PPTs) in both single shot and repetitive operatingmodes. Using this stand, momentum per pulse was determined strictly as a function of thrust stand deflection, spring stiffness, and natural frequency. No empirical corrections were required. The accuracy of the method was verified using a swinging impact p...

engine and airframe manufacturers for decades have cited the direct relationship between engine wear and high exhaust gas temperature (EGT) in recommending that operators use less than maximum takeoff thrust whenever possible. While the cost benefits of reduced-thrust takeoffs are thoroughly documented, the safety benefits are not as well understood. Thus, there is a common perception that usin...

A literature review, a datasheet review, and in-house experimental data were used to obtain a real-world comparison between bio-mimetic pectoral fins and traditional propeller-based thrusters. Only power consumption, forward thrust, and propulsive efficiency are compared. Scaling trends for both propulsion forms are discussed. Traditional thrusters are determined to be more efficient than curre...

In Sepioteuthis lessoniana, the oval squid, ontogenetic changes in the kinematics of the mantle during escape-jet locomotion imply a decline in the relative mass flux of the escape jet and may affect the peak weight-specific thrust of the escape jet. To examine the relationship between ontogenetic changes in the kinematics of the mantle and the thrust generated during the escape jet, we simulta...

[1] High-resolution topography generated from stereo HiRISE (High-Resolution Imaging Science Experiment) imagery reveals the meter-scale structure of interior layered deposits (ILD) in southwest Candor Chasma. This study seeks to determine the age of the local ILD relative to any normal faults that can be attributed to chasma formation. The study area is located near the contact of these ILD an...

It is well known that each thruster on the SPHERE produces slightly different thrust and behaves differently (see [Chen] and [Berkovitz]). Some methods were developed by [Chen] to compensate for the difference in thrust between thrusters and improve the open-loop performance of the SPHERE, but they were yet to be demonstrated. An experiment was performed onboard NASA’s KC-135, during microgravi...