@inproceedings{peters_2025,

title = {Peak Delta Frequency Regulates the Timing of Decisions},

author = {Logan Peters and Gregory Bales and Vincent Tran and Ariana Moghbel and Zhaodan Kong and Karen Moxon},

doi = {1111},

year  = {2025},

date = {2025-10-01},

booktitle = {2025 59th Asilomar Conference on Signals, Systems, and Computers (IEEE)},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{balesCognitiveCorrelatesEEG2018,

title = {Cognitive Correlates of EEG Spectral Power Indicate Human-Swarm Task Performance},

author = {Gregory Bales and Zhaodan Kong},

doi = {10.1145/3277593.3277613},

isbn = {978-1-4503-6564-2},

year  = {2018},

date = {2018-10-01},

booktitle = {Proceedings of the 8th International Conference on the Internet of Things},

pages = {1–6},

publisher = {ACM},

address = {Santa Barbara California},

abstract = {In this paper, we examine whether the geometric complexity of a robotic group affects performance in a human-swarm target acquisition task, and if these changes are reflected in average neurophysiological and behavioral characteristics. This is one of the first studies to utilize both the distribution of EEG spectral power and external behaviors to paint a more complex interaction between cognitive processes, behaviors, and task performance. Our results show that increasing the geometric complexity of the robotic group reduced task performance by 48.5%. Furthermore, the decrease in performance is accompanied by an increase in neurological measures that indicate more internal processing and suppression of visual stimuli. Accompanying changes in gaze and control activity enforce these differences.},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{Gregory_Bales_149653420,

title = {The Impact of Dynamic Complexity on Human-Multi-Agent Performance: A Neuro-Behavioral Perspective},

author = {Gregory Bales and Zhaodan Kong},

year  = {2018},

date = {2018-01-01},

booktitle = {2nd IFAC Conference on Cyber-Physical & Human-Systems (CPHS’18), Miami, FL},

address = {Miami, FL},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{Bales_2017,

title = {Neurophysiological and behavioral studies of human-swarm interaction tasks},

author = {Gregory Bales and Zhaodan Kong},

url = {http://dx.doi.org/10.1109/smc.2017.8122684},

doi = {10.1109/smc.2017.8122684},

year  = {2017},

date = {2017-10-01},

booktitle = {2017 IEEE International Conference on Systems, Man, and Cybernetics (SMC)},

publisher = {IEEE},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{Glaese_2010,

title = {Reduction of Dynamic Response of a Wind Tunnel Sting Mount Using a Hub Damper Unit},

author = {Roger Glaese and Gregory Bales and Sean Hsu and Marat Mor and Bob Stirling},

url = {http://dx.doi.org/10.2514/6.2010-1307},

doi = {10.2514/6.2010-1307},

year  = {2010},

date = {2010-01-01},

booktitle = {48th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition},

publisher = {American Institute of Aeronautics and Astronautics},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{balesActiveDampingVibration2006,

title = {Active Damping and Vibration Control for Aircraft Fin and Appendage Structures},

author = {Gregory Bales and Eric Anderson and Roger Glaese and Leonard Shaw},

doi = {10.2514/6.2006-653},

isbn = {978-1-62410-039-0},

year  = {2006},

date = {2006-01-01},

booktitle = {44th AIAA Aerospace Sciences Meeting and Exhibit},

publisher = {American Institute of Aeronautics and Astronautics},

address = {Reno, Nevada},

abstract = {Numerous vibration control techniques, employing both passive and active methods, have been developed and tested over the last several decades. Some of these techniques are in widespread use, while others have rarely or never left the laboratory. This paper considers the value that vibration damping and control of aircraft fins and appendage structures can have in reducing loads and subsequent fatigue and possible failure. These structures often are subject to high loads resulting from wakes of upstre am external stores. The vibration control methods were considered as part of a larger study focused on active flow control. The options for passive or active vibration control on a class of fin -type structures are reviewed, and one approach – active and passive damping using piezoelectric materials – is covered in greater detail. Piezoelectric transducer sizing for expected pressure loading and modeling of piezoelectric -based active damping control systems are discussed. Motivation for another possible techniques coupling active flow and vibration control is presented using arguments from adaptive filtering and feedforward control. Results are presented for bench tests with simulated disturbances, for low speed wind tunnel tests, and for high speed wind tunnel tests},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{sneedDevelopmentSmartMaterialHydraulic2006,

title = {Development of Smart Material-Hydraulic Pumps and Actuators},

author = {Ryan C. Sneed and Roland R. Smith and Michael F. Cash and Gregory L. Bales and Eric H. Anderson},

doi = {10.1115/IMECE2006-15896},

isbn = {978-0-7918-4765-7},

year  = {2006},

date = {2006-01-01},

booktitle = {Aerospace},

pages = {435–443},

publisher = {ASMEDC},

address = {Chicago, Illinois, USA},

abstract = {Smart materials such as piezoelectrics and magnetostrictives produce mechanical power in a form that is improperly matched to many applications. When packaged in typical ways, these stiff materials have excess force but are deficient in displacement. Recent research has suggested that smart materials can be used for the pressurization and pump stage in electrohydrostatic actuators (EHAs). EHAs offer advantages over traditional centralized hydraulic systems by providing local pressurization in a closed fluid system and eliminating the need for distributed, high-pressure fluid lines. Given inherent material power densities, smart material-based EHAs could produce higher power output compared to electromagnetic actuators. High frequency, low displacement smart material actuation, typically operated in the range of 500 Hz, but in some cases much higher, is rectified via fluid flow to produce larger output displacements at lower frequencies. Valve limitations, mechanical compliances, and fluid compressibility account for significant losses in the pumps. Continuing previous research, this paper describes design approaches that address and attempt to minimize losses. Piezoelectric and magnetostrictive devices are compared, and the design and testing of magnetostrictive pumps is described in greater detail, with special considerations given to heat generation and improved efficiency.},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{glaeseDemonstrationDynamicTailoring2004,

title = {Demonstration of Dynamic Tailoring for Gossamer Structures},

author = {Roger Glaese and Greg Bales},

doi = {10.2514/6.2004-1824},

isbn = {978-1-62410-079-6},

year  = {2004},

date = {2004-04-01},

booktitle = {45th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics & Materials Conference},

publisher = {American Institute of Aeronautics and Astronautics},

address = {Palm Springs, California},

abstract = {A structure for demonstrating dynamic tailoring for gossamer structures is presented. This demonstration structure consists of a torus with stiffening ``dimples'' and an attached central membrane. As a performance metric for evaluating the tailoring approaches, three reaction mass actuators were used to drive the torus while the velocity of the central membrane was measured with a laser vibrometer. Four types of dynamic tailoring were demonstrated. Inert masses were attached to the torus at the disturbance input locations and random locations to increase the effective impedance of the structure. Lightweight tuned mass dampers were attached to the torus in an attempt to reduce the vibration in a narrowband region. Because the central membrane is only attached to the torus at a discrete number of points and all disturbance energy must pass through these junctions, piezoelectric polymer patches were attached to the membrane at these locations. Passive shunting of these piezoelectric patches with resistors was implemented to show broadband vibration attenuation of the membrane. Finally, along with nearly collocated piezoelectric strain sensors, these piezoelectric patches were used as actuators in an active feedback control system using three controllers of increasing complexity. A fourth controller was implemented using the laser vibrometer measurement of a single spot in the center of the membrane as the feedback sensor. Experimental data is presented for each of these dynamic tailoring approaches.},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{erich.andersonApplicationSmartMaterialhydraulic2003a,

title = {Application of Smart Material-Hydraulic Actuators},

author = {Eric H. Anderson and Gregory L. Bales and Edward V. White},

doi = {10.1117/12.483896},

year  = {2003},

date = {2003-08-01},

booktitle = {Proc.SPIE},

volume = {5054},

abstract = {The application of a new class of actuators is considered. The actuators under development combine a high energy density smart material, specifically a piezoelectric material, with internal servohydraulic components. Large displacement outputs are produced, while the high force capacity of the stiff smart material is retained, for a net high-energy output. The actuator is considered ``power-by-wire'' because only electrical power is provided from the vehicle or system controller. A primary motivating application is in unmanned combat air vehicles (UCAVs). The particular actuation needs of these vehicles, in flight control and other utility functions, are described and distilled to a set of relevant device requirements. Other potential applications, such as flight motion simulation, are also highlighted. The new actuation architecture offers specific advantages over centralized hydraulic systems and has capabilities not present in electromechanical actuators (EMAs). The main advantage over centralized hydraulic systems is the elimination of the need for hydraulic lines. Compared to motor-driven ball screw type EMAs, the new actuators offer higher frequency response, and a larger peak-to-average output. A laboratory test facility designed to represent the loading experienced by a UCAV control surface is described. Key steps necessary to flight qualify the actuator are introduced.},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{Bales_2003,

title = {Experimental Issues that Impact In-Vacuum Dynamic Characterization of Thin Film Membranes},

author = {Greg Bales and Jonathan Hall and Eric Flint and Roger Glaese},

url = {http://dx.doi.org/10.2514/6.2003-1743},

doi = {10.2514/6.2003-1743},

year  = {2003},

date = {2003-04-01},

booktitle = {44th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference},

publisher = {American Institute of Aeronautics and Astronautics},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{Flint_2003,

title = {Experimentally Characterizing the Dynamics of 0.5m+ Diameter Doubly Curved Shells made from Thin Films},

author = {Eric Flint and Greg Bales and Roger Glaese and Rodney Bradford},

url = {http://dx.doi.org/10.2514/6.2003-1831},

doi = {10.2514/6.2003-1831},

year  = {2003},

date = {2003-04-01},

booktitle = {44th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference},

publisher = {American Institute of Aeronautics and Astronautics},

keywords = {},

pubstate = {published},

tppubtype = {inproceedings}

}