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- Electrowetting (2)
- Heat transfer (2)
- Active load alleviation (1)
- Actuation (1)
- Air vehicle (1)
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- Atomic force microscopy (1)
- C-wings (1)
- Cooperative control (1)
- Coordination (1)
- Electrochemical diode (1)
- Energy harvesting (1)
- Force-displacement ramp (1)
- Ground vehicle (1)
- Mission planning (1)
- Numerical modeling (1)
- Polarity dependence (1)
- Tailless aircraft design (1)
- Target tracking (1)
- Thermal diffusion (1)
- Thermal resistance (1)
- Thin film (1)
- Tip extensions (1)
- UAV (1)
- Unmanned aircraft (1)
- Wing design optimization (1)
- Winglets (1)
- Young-Lippmann equation (1)
Articles 1 - 7 of 7
Full-Text Articles in Engineering
Moving Ground Target Tracking In Urban Terrain Using Air/Ground Vehicles, Timothy Mclain, Randal W. Beard, Mark Owen, Huili Yu
Moving Ground Target Tracking In Urban Terrain Using Air/Ground Vehicles, Timothy Mclain, Randal W. Beard, Mark Owen, Huili Yu
Faculty Publications
In this paper, we present a framework for tracking a moving target in urban environments using UAVs in cooperation with UGVs. The framework takes into account occlusions between the sensor and the target. The target state is modeled using the dynamic occupancy grid and the target motion model is built using a second-order Markov chain. Based on the target occupancy grid, we design the path planning algorithm to maneuver the UAV and the UGV to configurations where they can detect the target with high probability. Simulation results show the framework is successful in solving the target tracking problem in urban …
Energy Harvesting And Mission Effectiveness For Small Unmanned Air Vehicles, Mark J. Cutler, Timothy W. Mclain, Randal W. Beard, Brian Capozzi
Energy Harvesting And Mission Effectiveness For Small Unmanned Air Vehicles, Mark J. Cutler, Timothy W. Mclain, Randal W. Beard, Brian Capozzi
Faculty Publications
This paper explores the feasibility of improving unmanned air vehicle (UAV) mission effectiveness by extracting energy from the atmosphere. Specifically, we consider an aerial surveillance mission in the vicinity of a geographic ridge. Cross winds owing over the ridge produce regions of lift on the windward side that can be exploited to increase mission duration. Mission effectiveness is quantified using the seeability metric. Simulation results are presented for several observation target placements. Results indicate that seeability and imaging persistence can be improved by exploiting ridge lift. Simulations demonstrated that targets at ranges less than four times the ridge height were …
Note: Thermal Analog To Atomic Force Microscopy Force-Displacement Measurements For Nanoscale Interfacial Contact Resistance, Brian D. Iverson, John E. Blendell, Suresh V. Garimella
Note: Thermal Analog To Atomic Force Microscopy Force-Displacement Measurements For Nanoscale Interfacial Contact Resistance, Brian D. Iverson, John E. Blendell, Suresh V. Garimella
Faculty Publications
Thermal diffusion measurements on polymethylmethacrylate-coated Si substrates using heated atomic force microscopy tips were performed to determine the contact resistance between an organic thin film and Si. The measurement methodology presented demonstrates how the thermal contrast signal obtained during a force-displacement ramp is used to quantify the resistance to heat transfer through an internal interface. The results also delineate the interrogation thickness beyond which thermal diffusion in the organic thin film is not affected appreciably by the underlying substrate.
Bidirectional Electrowetting Actuation With Voltage Polarity Dependence, Nathan B. Crane, Alex A. Volinsky, Pradeep Mishra, Ajay Rajgadkar, Mehdi Khodayari
Bidirectional Electrowetting Actuation With Voltage Polarity Dependence, Nathan B. Crane, Alex A. Volinsky, Pradeep Mishra, Ajay Rajgadkar, Mehdi Khodayari
Faculty Publications
This work presents an electrowetting system in which the actuation direction depends on the polarity of the applied voltage. Since electrowetting response depends on the voltage squared, it is typically independent of voltage sign to first order. However, the introduction of an electrochemicaal diode into the equivalent electrical circuit permits polarity-dependent behavior. Electrochemical diodes were created by making holes in the dielectric. The aluminum electrodes passivate and prevent current flow in one direction, creating diode-like behavior with high breakdown voltage. The resulting actuation forces were directly measured and are of comparable magnitude for both actuation directions.
Multidisciplinary Considerations In The Design Of Wings And Wing Tip Devices, Andrew Ning, Ilan Kroo
Multidisciplinary Considerations In The Design Of Wings And Wing Tip Devices, Andrew Ning, Ilan Kroo
Faculty Publications
Conceptual wing design analysis methods are combined with numerical optimization to find minimum drag wings subject to constraints on lift, weight, pitching moment, and stall speed. Tip extensions and winglets designed for minimum drag achieve similar performance, with the optimal solution depending on the ratio of the maneuver lift coecient to the cruise lift coecient. The results highlight the importance of accounting for the depth of the wing structural box in the weight model, and including constraints on stall speed. For tailless aircraft, C-wings show a slight performance advantage over wings with winglets when longitudinal trim and stability constraints are …
Characterization Of Electrowetting Processes Through Force Measurements, Nathan B. Crane, Pradeep Mishra, Alex A. Volinsky
Characterization Of Electrowetting Processes Through Force Measurements, Nathan B. Crane, Pradeep Mishra, Alex A. Volinsky
Faculty Publications
A new method of characterizing electrowetting is presented in which the forces applied to a modified nanoindenter tip by a test water droplet are measured. A droplet is trapped between the flat nanoindenter tip and the test substrate containing the necessary electrodes. When voltage is applied to the electrodes in the substrate, lateral and normal forces are exerted on the tip and measured by the nanoindenter transducer. Proper selection of the tip geometry permits direct prediction of the resulting in-plane lateral forces using analytical formulas derived from the Young-Lippmann equation. Experimental results show good agreement with both analytical and numerical …
Thermal Analog To Afm Force-Displacement Measurements For Nanoscale Interfacial Contact Resistance, Brian D. Iverson, John E. Blendell, Suresh V. Garimella
Thermal Analog To Afm Force-Displacement Measurements For Nanoscale Interfacial Contact Resistance, Brian D. Iverson, John E. Blendell, Suresh V. Garimella
Faculty Publications
Thermal diffusion measurements on PMMA-coated Si substrates using heated AFM tips were performed to determine the contact resistance between an organic thin film and Si. The measurement methodology presented demonstrates how the thermal contrast signal obtained during a force-displacement ramp is used to quantify the resistance to heat transfer through an internal interface. The results also delineate the interrogation thickness beyond which thermal diffusion in the organic thin film is not affected appreciably by the underlying substrate.