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To aid this research a library of feature fitting algorithms is developed in parallel. The library consists of least squares, Chebyshev and one sided fits applied on the features of line, plane, circle and cylinder. The proposed normative procedures are useful for evaluating tolerances in CMMs. The results evaluated will be in accordance to the standard. The ambiguity in choosing the algorithms is prevented. The software developed can be used in quality control for inspection purposes.
represents a configuration similar to the Airbus A320, to perform trade studies to understand the weight and configuration effects of “out-of-trim” flight during takeoff, cruise, initial approach, and balked landing. It is found that flying an aircraft slightly above the angle of attack or pitch angle required for a trimmed, stabilized flight will cause the aircraft to lose speed rapidly. This effect is most noticeable for lighter aircraft and when one engine is rendered inoperative. In the event of an engine failure, if the pilot does not pitch the nose of the aircraft down quickly, speed losses are significant and potentially lead to stalling the aircraft. Even when the risk of stalling the aircraft is small, the implications on aircraft climb performance, obstacle clearance, and acceleration distances can still become problematic if the aircraft is not flown properly. When the aircraft is slightly above the trimmed angle of attack, the response is shown to closely follow the classical phugoid response where the aircraft will trade speed and altitude in an oscillatory manner. However, when the pitch angle is slightly above the trimmed condition, the aircraft does not show this phugoid pattern but instead just loses speed until it reaches a new stabilized trajectory, never having speed and altitude oscillate. In this event, the way a pilot should respond to both events is different and may cause confusion in the cockpit.
The blunt leading-edge wings have less drag because the normal vector of the surface in the front section of the airfoil develops forces at opposed skin friction. The shape of the leading edge, in conjunction with the effect of viscosity, slightly alter the span load; both the magnitude of the lift and the transverse distribution. Another goal in this study is to verify the veracity of wake survey theory; the two different leading-edge shapes reveals the shortcoming of Mclean’s equation which is only applicable to blunt leading-edge wings.
This work addresses this issue with a tool used to predict and calculate the Minimum Control Speed on the Ground (VMCG) as well as the Minimum Control Airspeed (VMCA) of any existing or design-stage airplane. With simple line art of an airplane, a program called VORLAX is used to generate an aerodynamic database used to calculate the stability derivatives of an airplane. Using another program called Numerical Propulsion System Simulation (NPSS), a propulsion database is generated to use with the aerodynamic database to calculate both VMCG and VMCA.
This tool was tested using two airplanes, the Airbus A320 and the Lockheed Martin C130J-30 Super Hercules. The A320 does not use an Automatic Thrust Control System (ATCS), whereas the C130J-30 does use an ATCS. The tool was able to properly calculate and match known values of VMCG and VMCA for both of the airplanes. The fact that this tool was able to calculate the known values of VMCG and VMCA for both airplanes means that this tool would be able to predict the VMCG and VMCA of an airplane in the preliminary stages of design. This would allow design engineers the ability to use an Automatic Thrust Control System (ATCS) as part of the design of an airplane and still have the ability to predict the VMCG and VMCA of the airplane.
Mission aviation groups operate aircraft in areas with limited infrastructure. Existing airdrop methods pose significant risk due to their lack of steerability. This thesis details the development of Manna, a system built to address these concerns. Manna provides an automated, low cost, safe steerable delivery platform, through a custom designed parafoil and guidance unit. Flight tests and simulations show that Manna can provide a safer alternative for critical air deliveries.
Mission aviation groups operate aircraft in areas with limited infrastructure. Existing airdrop methods pose significant risk due to their lack of steerability. This thesis details the development of Manna, a system built to address these concerns. Manna provides an automated, low cost, safe steerable delivery platform, through a custom designed parafoil and guidance unit. Flight tests and simulations show that Manna can provide a safer alternative for critical air deliveries.
This report describes the findings of an experiment designed to explore the nature of human hearing using binaural sound. The experiment also set out to determine a way to accurately find positional data from sound. Binaural recordings were made of high frequency sounds at various angles and the data was postprocessed to find the group delay and difference of intensity between the two channels. To do this, two methods were used. The first relied on manually analyzing the data by visually looking for the points of interest. The second method used a MATLAB program to scan the data for the points of interest by using a Fourier analysis. It was determined that while the first method has the potential to provide better results it is impractical and not representative of how human hearing works. The second method was far more efficient and demonstrated the reliance of human hearing on the difference of intensities. It was determined that through the use of the second method accurate positional data could be obtained by comparing the differences with experimental data.
A robust autopilot control system for a ground vehicle was designed, fabricated, and implemented on a remote control car. The autopilot system consists of navigation, guidance, and three controller subsystems. The autopilot’s hardware subsystems are an Arduino processor, GPS receiver, 9 DOF inertial measurement system, and an SD card data logger. A complete system simulation was developed and used to verify the integrated design and algorithms, prior to field testing. The simulation results indicated the system performs as designed, with no anomalous behaviors observed. Simulations were also used to assess and verify each of the three controllers’ robustness qualities. The complete hardware system was field tested and verified fully functional against complex mission scenarios. The system performed as designed, with no anomalous behaviors observed. The system performed successfully in the presence of external disturbances (e.g., rocks, holes, dirt piles in the vehicle’s path), which demonstrated and verified the design is robust. Additional robustness testing consisted of doubling the vehicle’s polar moment of inertia and verifying this did not have any adverse effects on system performance. All the planned tasks were completed and the project’s objectives were met.