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The authors measured the vibratory forces acting on an airfoil model by performing a ground vibration test (GVT). The airfoil model was manufactured using rapid prototyping. In the experiments, the airfoil model's structural response was also recorded and described. This paper detailedly introduces the entire experiment process and the obtained experimental data agreed well to the actual values.

A cost effective, portable particulate control system was developed, built, and evaluated at the University of Louisiana at Lafayette. Prototype of the presented system was developed for experimental assessment and its computational model was also created for CFD simulation. The experimental and computer simulation results showed that the developed system could efficiently and safely remove and dispose accumulated particulate matter (in the size range of 5 ∼ 1000 μm), and be tolerant to the abrasive properties that the particulate matter may have. The developed particulate control system as well as the applied technology can be further optimized and extended to be applied in aerospace and space engineering to remove suspended particles out from the closed cabinet of aircrafts or spacecrafts. The outcome of this project will also impact other commercial sectors and industries.

This paper validates a simplified finite element model of a light duty truck chassis which was previously developed. The simplified model is used for different computational crash simulations including full frontal impact, offset frontal impact, and oblique impact. The simulation results are compared with those obtained from a detailed chassis model. Through the comparisons, it is found that the present simplified model can be successfully used in the full frontal and offset frontal simulations. However, the current simplified model still needs to be innovated in order to correctly predict the detailed model’s crash behavior during the oblique impact. The present simplified model’s computational stability, reliability, accuracy, and efficiency are verified in this project.

This paper presented methods to determine the aerodynamic forces that act on an aircraft wing during flight. These methods are initially proposed for a simplified two degree-of-freedoms airfoil model and then are extensively applied for a multi-degree-of-freedom airfoil system. Different airspeed conditions are considered in establishing such methods. The accuracy of the presented methods is verified by comparing the estimated aerodynamic forces with the actual values. A good agreement is achieved through the comparisons and it is verified that the present methods can be used to correctly identify the aerodynamic forces acting on the aircraft wing models.

A dynamic modeling framework was established to predict status (position, displacement, velocity, acceleration, and shape) of a towed vehicle system with different driver inputs. This framework consists of three components: (1) a state space model to decide position and velocity for the vehicle system based on Newton’s second law; (2) an angular acceleration transferring model, which leads to a hypothesis that the each towed unit follows the same path as the towing vehicle; and (3) a polygon model to draw instantaneous polygons to envelop the entire system at any time point. Input parameters of this model include initial conditions of the system, real-time locations of a reference point (e.g. front center of the towing vehicle) that can be determined from a beacon and radar system, and instantaneous accelerations of this system, which come from driver maneuvers (accelerating, braking, steering, etc.) can be read from a data acquisition system installed on the towing vehicle.

Differential equations play a prominent role in aerospace engineering by modeling aerospace structures, describing important phenomena, and simulating mathematical behavior of aerospace dynamical systems. Presently, aerospace systems have become more complex, space vehicle missions require more hours of simulation time to complete a maneuver, and high-performance missiles require more logical decisions in there phases of flight. Because of these conditions, a computationally efficient algorithm for solving these differential equations is highly demanded to significantly reduce the computing time. This paper presents an efficient method for solving the differential equations by using variational iteration method, which can be implemented into software package to dramatically reduce the computing time for simulating the aerospace systems thereby significantly improving computer's performance in real-time design and simulation of aircrafts, spacecrafts, and other aerospace vehicles.

This paper presents a computational study to investigate effects of crystal orientations on plasticity and damage of copper crystal at atomic scale. In the present study, a single crystal copper model was created as a target, which was struck and penetrated by a single crystal nickel. Three orientations, single slip system [1 0 1, 1 2 -1, -1 1 1], double slip system [1 1 2, 1 1 0, 1 1 -1], and octal slip system [1 0 0, 0 1 0, 0 0 1], were applied to the copper crystal. Their effects on plasticity and damage behavior of the single crystal copper were studied and compared using molecular dynamics simulations. Modified Embedded Atom Method potentials were applied to determine the pair interactions between the copper and nickel atoms.

The autonomous collision avoidance problem for multi-trailer vehicle maneuvering is investigated in this paper. Different from conventional vehicle systems that contain one single moving part or multi-parts that can be considered as one rigid body, the interconnection between the tractor and each trailer, and interactions between trailers in the multi-trailer system introduce a high dimensional and highly complex dynamic system for the controller design. The external disturbance and parametric uncertainties further increase the difficulty in system identification and state space formulation. To implement a real time control system for various scenarios where the locations and states of the obstacles are not known beforehand, a supervisory algorithm is designed to convert the control problem to a discrete event system. The model predictive control (MPC) using limited lookahead policy is employed in the proposed algorithm.

Oven and flame tests were designed and conducted to evaluate the heat resistance of a ceramic coating material, Cerakote C-7700Q, and evaluate its viability to replace the intumescent coating as one painting material for helicopter engine cowlings. The test results showed that the currently used painting scheme of the engine cowlings failed the 220°C oven test while after replacing the epoxy seal coat with the Cerakote, the new painting system passed the 220°C test in regards to painting bubbling. This study explained why serious appearance defects occurred in the inner skin of the engine cowling when the aircraft is hovering and suggested that one most time- and cost-effective solution is to repaint the current engine cowlings with a new three coating system of Cerakote, surface protection HS7072-622, and intumescent paint as a fireproof lacquer.