Open Access. Powered by Scholars. Published by Universities.®

Aerospace Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Faculty Publications

Discipline
Institution
Keyword
Publication Year

Articles 121 - 125 of 125

Full-Text Articles in Aerospace Engineering

Portfolio Assessment In Aerodynamics, Nikos J. Mourtos Apr 1999

Portfolio Assessment In Aerodynamics, Nikos J. Mourtos

Faculty Publications

A new way of assessing student learning in an aerodynamics course through the use of portfolios is presented. The approach is portable to any engineering course, with a few modifications depending on content. The main idea is to allow students more responsibility for their own learning. Instead of having everyone in the class perform identical activities (homework, experiments, projects, tests, etc.), a cadre of assignments is made available to them. Students choose and perform (within reason) the ones that suit them better in terms of their own strengths and learning styles. The ultimate goal is for each student to demonstrate …


Development And Experimental Validation Of An Underwater Manipulator Hydrodynamic Model, Timothy W. Mclain, Stephen M. Rock Jul 1998

Development And Experimental Validation Of An Underwater Manipulator Hydrodynamic Model, Timothy W. Mclain, Stephen M. Rock

Faculty Publications

Hydrodynamic forces can be large and hence have a significant effect on the dynamic performance of underwater manipulation systems. this paper investigates these forces for a cylindrical single-link arm undergoing motions that are characteristics of a robotic manipulator. Based on flow visualization, theoretical analysis, and experimental measurements, a new model is developed that describes these forces. This model differs from previous models in that the drag and added-mass coefficients are state-dependent functions that depend on the distance traveled by the arm. A factor of four improvement in accuracy is demonstrated over standard constant-coefficient models.


The Nuts & Bolts Of Cooperative Learning In Engineering, Nikos J. Mourtos Nov 1994

The Nuts & Bolts Of Cooperative Learning In Engineering, Nikos J. Mourtos

Faculty Publications

A great number of engineering students work alone. But in industry, teamwork is required most of the time. Incorporating Cooperative Learning (CL) into an engineering program gives students an opportunity to practice problem solving and communication skills in a "simulated" professional environment. The paper briefly discusses the motivation behind using CL in engineering courses. Then, the essential elements to make CL successful in the classroom are examined and examples of how these elements have been incorporated into engineering courses taught by the author are given. Problems that have been encountered along with possible fixes are also mentioned.


Control Of Vortical Separation On A Circular Cone, Nikos J. Mourtos Jul 1990

Control Of Vortical Separation On A Circular Cone, Nikos J. Mourtos

Faculty Publications

For conical bodies, at moderate angles of attack, the flow separates from the lee side, forming two vortices. Although the vortex lift contrihution is highly desirable, as the angle of attack increases, the vortex system becomes asymmetric, and eventually the vortices breakdown. Thus, some control of the separation process is necessary if the vortex lift is to be exploited at higher angles of attack. The theoretical model which is used in this analysis has three parts. First, the 'single line-vortex' model is used within the framework of 'slender-body theory' to compute the outer inviscid field for specified separation lines. Second, …


Modal Control Of An Unstable Periodic Orbit, William Wiesel, William Shelton Jan 1983

Modal Control Of An Unstable Periodic Orbit, William Wiesel, William Shelton

Faculty Publications

We apply Floquet theory to the problem of designing a control system for a satellite in an unstable periodic orbit. Expansion about a periodic orbit produces a time periodic linear system, which is augmented by a time periodic control term. We show that this can be done such that a) the application of control produces only inertial accelerations, b) positive real Poincare exponents are shifted into the left half-plane, and c) the shift of the exponent is linear with control gain. We apply these developments to an unstable orbit near the Earth-Moon L3 point perturbed by the Sun. Finally, …