Journal articles

@article{HeX_2024,

title = {Rotorcraft in-ground effect models in axial and forward flight},

author = {X. He and K. K. Leang},

year  = {2024},

date = {2024-11-16},

urldate = {2024-11-16},

journal = {Aerospace Science and Technology (in press)},

abstract = {This paper describes in-ground effect (IGE) models that incorporate the rotor advance ratio and vehicle's climbing velocity to predict the IGE thrust variation in axial (vertical) and forward flight for rotor-based aerial vehicles. Extensive experiments are conducted to validate each and every component of the new IGE models. Discrepancies between the analytical and experimental results in forward flight are found consistent with the two characteristic flow regimes of recirculation and ground vortex. In particular, an additional thrust increase at a low advance ratio (<0.04) in an extreme ground-effect regime (z/R<0.5) is observed. The results of this study can be leveraged to develop new vehicle motion control and path planning algorithms for flight near obstacles.},

keywords = {},

pubstate = {forthcoming},

tppubtype = {article}

}

@article{HoffmanKC_2025_LDSC,

title = {Rapid Airborne Gas-plume Mapping and Source Localization with Feedforward Gas-sensor Dynamics Compensation},

author = {K. C. Hoffman and J. M. Anderson and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/HoffmanKC_2024.pdf},

doi = {https://doi.org/10.1115/1.4066513},

year  = {2024},

date = {2024-09-30},

urldate = {2024-09-30},

journal = {ASME Letters in Dynamic Systems and Control},

volume = {4},

number = {4},

pages = {041002},

abstract = {This paper focuses on improving the speed, accuracy, and robustness of autonomous aerial-based chemical-sensing for plume mapping and source localization through characterizing, modeling, and feedforward compensation of gas sensor dynamics. First, the dynamics of three types of gas sensors are modeled. Second, the maximum chemical mapping speed is calculated and shown to be inversely proportional to sensor time constant. Third, an inversion-based approach is used to compensate for the sensor dynamics to improve mapping throughput. Results show that dynamics compensation enhances the chemical-mapping speed by over five times compared to the uncompensated case. Finally, to further demonstrate utility, the approach is applied to a particle swarm optimization example for plume-source localization. The improvement is observed by how well the agents converge to the true chemical-gas source location when gas-sensor dynamics are taken into account. Specifically, for a static Gaussian plume source, feedforward compensation leads to 64% average improvement in localization success; and for a dynamic Quick Urban and Industrial Complex (QUIC) dispersion plume source, a 39% average improvement is observed. These results underscore the importance of sensor-dynamics compensation for enhancing mapping and source localization throughput, accuracy, and robustness.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{SteinerJA_2024_JMR,

title = {Magnetically-actuated Endoluminal Soft Robot with Electroactive Polymer Actuation for Enhanced Gait Performance},

author = {J. A. Steiner and W. S. Nagel and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/SteinerJA_2024_JMR.pdf},

doi = {https://doi.org/10.1115/1.4066130},

year  = {2024},

date = {2024-08-22},

urldate = {2024-08-22},

journal = {ASME J. Mechanisms and Robotics (In press)},

volume = {16},

number = {10},

pages = {104503},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{OlsenNR_2024_JDSMC,

title = {Information-Theoretic Bayesian Inference for Multi-Agent Localization and Tracking of an RF Target with Unknown Waveform},

author = {N. R. Olsen and S. M. McKee and O. S. Haddadin and S. M. Lyon and J. E. Campbell and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/OlsenNR_2024_JDSMC.pdf},

doi = {10.1115/1.4065592},

year  = {2024},

date = {2024-08-22},

urldate = {2024-08-22},

journal = {ASME J. Dyn. Syst. Meas. and Cont., Special Issue on Data-Driven Modeling and Control of Dynamical Systems (https://doi.org/10.1115/1.4066453)},

volume = {146},

issue = {6},

pages = {061104},

abstract = {Information-theoretic motion planning and machine learning through Bayesian inference are exploited to localize and track a dynamic radio frequency (RF) emitter with unknown

waveform (uncooperative target). A target-state estimator handles non-Gaussian distributions, while mutual information is utilized to coordinate the motion control of a network of mobile sensors (agents) to minimize measurement uncertainty. The mutual information is computed for pairs of sensors through a four-permutation-with-replacement process. The information surfaces are combined to create a composite map, which is then used by agents to plan their motion for more efficient and effective target estimation and tracking. Simulations and physical experiments involving micro-aerial vehicles with time difference of arrival (TDOA) measurements are performed to evaluate the performance of the algorithm. Results show that when two or three agents are used, the algorithm outperforms state-of-the-art methods. Results also show that for four or more agents, the performance is as competitive as an idealized static sensor network.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{NagelWS_2024_SMS,

title = {Engineered IPMC Sensors: Modeling, Characterization, and Application towards Wearable Postural-tactile Measurement},

author = {W. S. Nagel, O. Fakharian, M. Aureli, K. K. Leang},

doi = {10.1088/1361-665X/ad142b},

year  = {2023},

date = {2023-12-22},

urldate = {2023-12-22},

journal = {Smart Materials and Structures},

volume = {33},

pages = {015035  (12 pages)},

abstract = {This paper focuses on the modeling and development of engineered ionic polymer-metal composite (eIPMC) sensors for applications such as postural and tactile measurement in mechatronics/robotics-assisted finger rehabilitation therapy. Specifically, to tailor the sensitivity of the device, eIPMCs, fabricated using a polymer-surface abrading technique, are utilized as the sensing element. An enhanced chemoelectromechanical model is developed that captures the effect of the abrading process on the multiphysics sensing behavior under different loading conditions. The fabricated sensors are characterized using scanning electron microscopy imaging and cyclic voltammetry and chronoamperometry. Results show significant improvement in the electrochemical properties, including charge storage, double layer capacitance, and surface conductance, compared to the control samples. Finally, prototype postural-tactile finger sensors composed of different eIPMC variants are created and their performance validated under postural and tactile experiments. The tailored eIPMC sensors show increased open-circuit voltage response compared to control IPMCs, with 7.7- and 4.7-times larger peak-to-peak bending response under postural changes, as well as a 3.2-times more sensitive response under compression during tactile loading, demonstrating the feasibility of eIPMC sensors.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{McKeeSM_2022_JAVS,

title = {Feedforward Mutual-Information Anomaly Detection: Application to Autonomous Vehicles},

author = {S. M. McKee, O. S. Haddadin and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/McKeeSM_2024_JAVS.pdf},

doi = {10.1115/1.4064519},

year  = {2022},

date = {2022-10-01},

urldate = {2024-02-13},

journal = {ASME Journal of Autonomous Vehicles and Systems},

volume = {2},

number = {041003 (7 pages)},

issue = {4},

abstract = {This paper describes a mutual-information (MI)-based approach that exploits a dynamics model to quantify and detect anomalies for applications such as autonomous vehicles. First, the MI is utilized to quantify the level of uncertainty associated with the driving behaviors of a vehicle. The MI approach handles novel anomalies without the need for data-intensive training; and the metric readily applies to multivariate datasets for improved robustness compared to, e.g., monitoring vehicle tracking error. Second, to further improve the response time of anomaly detection, current and past measurements are combined with a predictive component that utilizes the vehicle dynamics model. This approach compensates for the lag in the anomaly detection process compared to strictly using current and past measurements. Finally, three different MI-based strategies are described and compared experimentally: anomaly detection using MI with (1) current and past measurements (reaction), (2) current and future information (prediction), and (3) a combination of past and future information (reaction–prediction) with three different time windows. The experiments demonstrate quantification and detection of anomalies in three driving situations: (1) veering off the road, (2) driving on the wrong side of the road, and (3) swerving within a lane. Results show that by anticipating the movements of the vehicle, the quality and response time of the anomaly detection are more favorable for decision-making while not raising false alarms compared to just using current and past measurements.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{SteinerJS_2021_JMR,

title = {Modeling and Analysis of a Soft Endoluminal Inchworm Robot Propelled by Rotating Magnetic Dipole Fields},

author = {J. S. Steiner, L. Pham, J. J. Abbott and K. K. Leang},

year  = {2022},

date = {2022-10-01},

urldate = {2022-10-01},

journal = {ASME J. of Mechanisms and Robotics},

volume = {14},

issue = {5},

pages = {051002 (11 pages)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{NagelWS_2022_Tmech,

title = {Low-Coupling Hybrid Parallel-Serial-Kinematic Nanopositioner with Nonorthogonal Flexure: Nonlinear Design and Control},

author = {W. S. Nagel, S. Andersson, G. Clayton and K. K. Leang},

year  = {2022},

date = {2022-10-01},

urldate = {2021-11-18},

journal = {IEEE/ASME Transactions on Mechatronics},

volume = {27},

issue = {5},

pages = {3683-3693},

abstract = {This article focuses on the design and high-precision control of a new dual-stage, three-axis hybrid parallel-serial-kinematic nanopositioner developed specifically for feature-tracking applications with arbitrary scanning directions. Dual-actuation is achieved by integrating a three-axis shear piezoelectric actuator into the large-range planar stage. A novel nonorthogonal compliant motion-amplifying mechanism which reorients the lateral sample-platform displacement to align with the principal directions of the input piezoactuators is used to minimize parasitic (coupling) motion. A nonlinear rigid-link model and finite element analysis (FEA) are used to optimize over the orientation parameter during the design process. A prototype stage is manufactured and tested, and the lateral and vertical travel ranges are approximately 18 × 21 and 1 μ m, respectively, with secondary lateral actuation in the range of 1 × 1 μ m. Coupling in the long-range stage is below -31 dB for both axes, an estimated 51 to 86% reduction compared to a traditional perpendicular-mechanism design. The measured dominant resonances for the lateral directions of the long-range stage are approximately 1.4 kHz, while short-range positioner resonances are approximately 11 and 40 kHz for the lateral and vertical directions, respectively. The design of a new feedforward-feedback controller is described, and the controller is implemented with field-programmable gate array (FPGA) hardware, where individual actuator contributions are intuitively determined by shaping the frequency response of their relative and summed displacements. An inverse hysteresis operator is used to linearize the plant behavior for effective motion control. Experimental tracking and atomic force microscopy (AFM) imaging results are presented to demonstrate the performance of the new mechanical and control system designs.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{HistedR_2021_SMS,

title = {Ionic Polymer Metal Composite Compression Sensors with 3D-Structured Interfaces},

author = {R. Histed, J. Ngo, O. Hussain, C. K. Lapins, O. Fakharian, K. K. Leang, Y. Liao, M. Aureli},

year  = {2021},

date = {2021-11-01},

urldate = {2021-10-01},

journal = {Smart Materials and Structures},

volume = {30},

number = {12},

pages = {125027},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{RaeymaekersB_2021_AIS,

title = {Manufacturing for the masses: a novel concept for consumer 3D printer networks in the context of crisis relief},

author = {B. Raeymaekers, K. K. Leang, M. Porfiri and S. Xu},

url = {http://www.kam.k.leang.com/academics/pubs/RaeymaekersB_2021.pdf},

doi = {https://doi.org/10.1002/aisy.202100121},

year  = {2021},

date = {2021-09-29},

journal = {Advanced Intelligent Systems},

pages = {202100121},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{GunawardenaN_2021,

title = {Particle swarm optimization for source localization in realistic complex urban environments},

author = {N. Gunawardena, K. K. Leang and E. R. Pardyjak},

doi = {https://doi.org/10.1016/j.atmosenv.2021.118636},

year  = {2021},

date = {2021-07-30},

journal = {Atmospheric Environment},

volume = {262},

pages = {118636},

abstract = {In this work, we present a method to localize a source in complex urban environments using particle swarm optimization (PSO). Instead of using PSO to minimize the difference between a plume model and measurements as is often done, PSO is run such that each particle is modeled by an unmanned aerial vehicle (UAV) that measures and directly finds the global maximum of the concentration field. Several modifications were made to PSO to allow it to perform successfully in this application. The synthetic data used to test PSO were produced using the 3D building resolving Quick Urban & Industrial Complex Dispersion Modeling System (QUIC), and PSO was implemented in Python. Three different domains were tested: (1) a case with no obstacles, (2) a case with four large obstacles, and (3) a real-world case modeled after the Joint Urban 2003 experiment in Oklahoma City. We found that PSO works well in idealized and real cases. In the Oklahoma City simulation, approximately 90% of the PSO runs with 10 particles make it to within 1% of the maximum domain distance to the source, and approximately 98% of the PSO runs with 50 particles make it to within 1% of the maximum domain distance to the source. However, PSO is not completely immune to local maxima, and there is the possibility of convergence to the wrong point in the domain. The insight from this study can be used to inform first responders or create a tool that can be implemented on UAVs to locate a contaminant source.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{JensonNau_2021_TASE,

title = {Near-Optimal Area-Coverage Path Planning of Energy Constrained Aerial Robots with Application in Autonomous Environmental Monitoring},

author = {K. R. Jenson-Nau, T. Hermans and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/JensonNauK_2020.pdf},

doi = {10.1109/TASE.2020.3016276},

year  = {2021},

date = {2021-07-01},

urldate = {2020-08-31},

journal = {IEEE Trans. on Automation Science and Engineering},

volume = {18},

issue = {3},

pages = {1453-1668},

abstract = {This article describes a Voronoi-based path generation (VPG) algorithm for an energy-constrained mobile robot, such as an unmanned aerial vehicle (UAV). The algorithm solves a variation of the coverage path-planning problem where complete coverage of an area is not possible due to path-length limits caused by energy constraints on the robot. The algorithm works by modeling the path as a connected network of mass-spring-damper systems. The approach further leverages the properties of Voronoi diagrams to generate a potential field to move path waypoints to near-optimal configurations while maintaining path-length constraints. Simulation and physical experiments on an aerial vehicle are described. Simulated runtimes show linear-time complexity with respect to the number of path waypoints. Tests in variously shaped areas demonstrate that the method can generate paths in both convex and nonconvex areas. Comparison tests with other path generation methods demonstrate that the VPG algorithm strikes a good balance between runtime and optimality, with significantly better runtime than direct optimization, lower cost coverage paths than a lawnmower-style coverage path, and moderately better performance in both metrics than the most conceptually similar method. Physical experiments demonstrate the applicability of the VPG method to a physical UAV, and comparisons between real-world results and simulations show that the costs of the generated paths are within a few percent of each other, implying that analysis performed in simulation will hold for real-world application, assuming that the robot is capable of closely following the path and a good energy model is available.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{MitrovicA_2019_TmechSpecialIssue,

title = {Closed-loop Range-Based Control of Dual-Stage Nanopositioning Systems},

author = {A. Mitrovic, W. S. Nagel, K. K. Leang and G. M. Clayton },

doi = {10.1109/TMECH.2020.3020047},

year  = {2021},

date = {2021-06-01},

urldate = {2021-06-01},

journal = {IEEE/ASME Transactions on Mechatronics},

volume = {26},

issue = {3},

pages = {1412-1421},

abstract = {In this paper, a closed-loop control framework for dual-stage nanopositioning systems is presented that allows the user to allocate control efforts to the individual actuators based on their range capabilities. Recent work by the authors has focused on range-based control of dual-stage actuators implemented as a prefilter, which assumes that each individual actuator has sensor feedback enabling them to be controlled separately. This paper seeks to address the problem of range-based control of dual-stage systems when sensor measurements are only available from the total output of the system, a commonly encountered design. This is a significant departure from previous work since the range-based filter is included in the dual-stage system feedback loop and stability becomes a concern. In this work, the controller is presented, stability conditions are determined, and imaging experiments are performed on an atomic force microscope (AFM). Tracking results show that the root-mean-square (RMS) tracking error for various triangular reference trajectories is improved with the presented range-based control structure by up to 50% compared to frequency-based methods.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{DevasiaS_2021,

title = {The American Control Conference [Conference report]},

author = {S. Devasia, M. Grover and K. K. Leang},

year  = {2021},

date = {2021-02-01},

journal = {IEEE Control Systems Magazine},

volume = {41},

number = {1},

pages = {82-86},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{PhamL_2020_TMRB,

title = {Soft Endoluminal Robots Propelled by Rotating Magnetic Dipole Fields},

author = {L. Pham, J. A. Steiner, K. K. Leang and J. J. Abbott},

url = {http://www.kam.k.leang.com/academics/pubs/PhamL_2020.pdf},

doi = {10.1109/TMRB.2020.3027871},

year  = {2020},

date = {2020-11-01},

journal = { IEEE Transactions on Medical Robotics and Bionics},

volume = {2},

number = {4},

pages = {598-607},

abstract = {Medical procedures often involve a device moving through a natural lumen of the human body (e.g., intestines, blood vessels). However, with existing technology, it is difficult, impossible, or traumatic to reach certain locations. In this article, we present a magnetically actuated soft-robotic concept for use in endoluminal applications (e.g., capsule endoscopes and catheters). The soft endoluminal robot is a simple device comprising two or more permanent magnets, axially magnetized and embedded co-axially with alternating polarity in a compliant body, with an optional internal lumen, actuated by an external rotating magnetic dipole field. We use simulations to elucidate the actuation concept’s underlying physics and, combined with experiments, demonstrate how the proposed concept outperforms other potential variations. We experimentally demonstrate the robustness to misalignment between the soft robot and the applied field, enabling operation in different applications without precise knowledge of the robot’s orientation or precise control of the actuator dipole field. Experiments are then performed inside a synthetic bowel to compare capsule-endoscope-size robots and multi-component robots formed by connecting multiple capsule-endoscope-size robots axially. Finally, experiments in a synthetic stomach show how the concept lends itself to directed self-assembly in the stomach, thus creating robots that are larger than could be swallowed.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{HeX_2019_AIAA_Journal,

title = {Quasi-Steady In-Ground-Effect Model for Single and Multi-Rotor Aerial Vehicles},

author = {X. He and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/HeX_2020_AIAA.pdf},

doi = {10.2514/1.J059223},

year  = {2020},

date = {2020-11-01},

journal = {AIAA Journal},

volume = {58},

number = {2},

pages = {5318 - 5331},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{BourneJR_2020_IJRR,

title = {Decentralized Multi-Agent Information-Theoretic Control for Target Estimation and Localization: Finding Chemical Leaks},

author = {J. R. Bourne, M. Goodell, X. He, J. Steiner and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/BourneJR_2020_IJRR.pdf},

doi = {https://doi.org/10.1177/0278364920957090},

year  = {2020},

date = {2020-07-17},

urldate = {2020-07-17},

journal = {International Journal of Robotics Research},

volume = {39},

number = {13},

pages = {1525 - 1548},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{GuoD_2019_IJRR,

title = {Image-based Estimation, Planning, and Control for High-speed Flying through Multiple Openings},

author = {D. Guo and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/GuoD_2020_IJRR.pdf},

doi = {https://doi.org/10.1177/0278364920921943},

year  = {2020},

date = {2020-06-27},

journal = {International Journal of Robotics Research, Vol. 39, No. 9, pp. 122-1137, 2020},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{MitrovicA_2019_Mechatronics,

title = {Analysis and Experimental Comparison of Range-based Control for Dual-Stage Nanopositioners},

author = {A. Mitrovic, K. K. Leang and G. M. Clayton },

doi = {https://doi.org/10.1016/j.mechatronics.2020.102371},

year  = {2020},

date = {2020-04-27},

journal = {Mechatronics, Vol. 69, pp. 102371, 2020},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{GuoD_2020_Tmech,

title = {Spatial-Temporal Trajectory Redesign for Dual-Stage Nanopositioning Systems with Application in AFM},

author = {D. Guo, B. Nagel, G. M. Clayton and K. K. Leang},

doi = {10.1109/TMECH.2020.2971755},

year  = {2020},

date = {2020-02-25},

journal = {IEEE/ASME Trans. on Mechatronics},

volume = {25},

number = {2},

pages = {558 - 569},

abstract = {This article focuses on trajectory redesign for dual-stage nanopositioning systems, where speed, range, and resolution are considered. Dual-stage nanopositioning systems are becoming increasingly popular due to their unique ability to achieve long-range and high-speed operation. Conventional trajectory assignment methods for dual-stage systems commonly consider frequency characteristics of the actuators, a process that can inappropriately allocate short-range, low-frequency components of a reference signal. A new systematic range-and-temporal-based trajectory-redesign process is presented, where the desired trajectory is first split based on achievable positioning bandwidth, and then, split spatially based on the achievable range and positioning resolution. Inversion-based feedforward control techniques are then used to compensate for the dynamic and hysteretic behaviors of a piezo-based prototype dual-stage positioner; this control architecture is selected to emphasize improvements achieved through the new trajectory-redesign method, as well as allow for implementation onto platforms with minimal sensing capabilities. Simulations and atomic force microscope experiments are included to demonstrate the success of this redesign procedure compared to approaches that consider frequency or range alone.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{GuoD_2020_RAL,

title = {Image-Based Estimation, Planning, and Control of Cable-Suspended Payload for Package Delivery},

author = {D. Guo and K. K. Leang},

doi = {10.1109/LRA.2020.2972855 },

year  = {2020},

date = {2020-01-29},

journal = {IEEE Robotics and Automation Letters},

volume = {5},

number = {2},

pages = {2698-2705},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{CarricoJD_2019_SR,

title = {3D-Printing and Machine Learning Control of Soft Ionic Polymer-Metal Composite Actuators},

author = {J. D. Carrico, T. Hermans, K. J. Kim and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/CarricoJD_2019_SR.pdf},

year  = {2019},

date = {2019-11-12},

journal = {Nature Scientific Reports, Soft sensors and actuators Collection},

volume = {9},

pages = {17482 },

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{BourneJR_2018a,

title = {Coordinated Bayesian-based Bio-Inspired Plume Source Term Estimation and Source Seeking for Mobile Robots},

author = {J. R. Bourne, E. Pardyjak, K .K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/BourneJR_2019_TRO.pdf},

year  = {2019},

date = {2019-05-28},

urldate = {2019-05-28},

journal = {IEEE Transactions on Robotics (DOI: 10.1109/TRO.2019.2912520)},

volume = {35},

number = {4},

pages = {967-986},

abstract = {A new non-parametric Bayesian-based motion planning algorithm for autonomous plume source term estimation (STE) and source seeking (SS) is presented. The algorithm is designed for mobile robots equipped with gas concentration sensors. Specifically, robots coordinate and utilize a Gaussian-plume likelihood model in a Bayesian-based STE process, then simultaneously search for and navigate toward the source through model-based, bio-inspired SS methods such as biased-random walk and surge-casting. Compared to state-of-the-art Bayesian and sensor-based STE/SS motion planners, the strategy described takes advantage of coordination between multiple robots and the estimated plume model for faster and more robust SS, rather than relying on direct (or filtered) sensor measurements which can be highly sensitive to noise and unsteady atmospheric conditions. A set of Monte Carlo simulation studies are conducted to compare the performance between the uncoordinated and coordinated algorithms for different robot team sizes and starting conditions. Additionally, the algorithms are validated experimentally through a laboratory-safe, realistic humid-air plume that behaves similar to gas plumes, to test STE and SS using mobile ground robots equipped with low-cost humidity sensors.  Simulation and experimental results show consistently that the coordinated Bayesian-based STE and SS algorithm outperforms traditional bio-inspired SS algorithms and is approximately twice as fast as the uncoordinated case. Finally, the plume source is distorted to study the algorithm’s limitations and impact on STE and SS, where results show that even for distorted plumes, useful source localization information can be obtained.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{HeX_2018_ASMEJDSMC,

title = {Multi-rotor In-Ground-Effect Modeling and Adaptive Nonlinear Disturbance Observer for Closed-loop UAV Control},

author = {X. He, G. Kou, M. Calaf and K. K. Leang,},

year  = {2019},

date = {2019-02-11},

journal = {ASME J. Dyn. Syst. Meas. and Cont., Special Issue: "Autonomous Mobile Systems" in Memory of Professor J. Karl Hedrick},

volume = {141},

pages = {071013 (11 pages)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{HeX_2018_ISJ,

title = {Autonomous Chemical Sensing Aerial Robot for Urban/Suburban Environmental Monitoring},

author = {X. He, J. R. Bourne, J. A. Steiner, C. Mortensen, K. C. Hoffman, C. J. Dudley, B. Rogers, D. M. Cropek and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/HeX_2019_ISJ.pdf},

year  = {2019},

date = {2019-02-10},

journal = {IEEE Systems Journal, Vol. 13, No. 3, pp. 3524 - 3535},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{LeangKK_2019_Tmech,

title = {Guest Editorial Focused Section on Soft Actuators, Sensors, and Components (SASC)},

author = {K. K. Leang, F. Iida, J. Paik, Y.-L. Park and J. Ueda},

year  = {2019},

date = {2019-02-07},

journal = {IEEE/ASME Transactions on Mechatronics, Focused Section, Vol. },

volume = {24},

number = {1},

pages = {1-4},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{SteinerJ_2019_RA,

title = {Open-Sector Rapid Reactive Collision Avoidance: Application in Aerial Robot Navigation Through Outdoor Unstructured Environments},

author = {J. Steiner, X. He and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/SteinerJA_2019.pdf},

year  = {2019},

date = {2019-02-01},

journal = {Robotics and Autonomous Systems},

volume = {112},

pages = {211-220},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{AdibnazariI_2018_IJIRA,

title = {A 3D-Printed 3-DOF Tripedal Microrobotic Platform for Unconstrained and Omnidirectional Sample Positioning},

author = {I. Adibnazari, W. S. Nagel and K. K. Leang},

year  = {2018},

date = {2018-11-06},

journal = {International Journal of Intelligent Robotics and Applications},

volume = {2},

number = {4},

pages = {425-435},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{GuoD_2018_ASME_JMR,

title = {Nonlinear Vision-based Observer for Visual Servo Control of an Aerial Robot in GPS-denied Environments},

author = {D. Guo, H. Wang and K. K. Leang},

year  = {2018},

date = {2018-11-01},

journal = {ASME J. Mechanisms and Robotics},

volume = {10},

number = {6},

pages = {061018},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{LeeJ_2017_ASME_JMR,

title = {Modular design and control of a fully-actuated hexrotor for aerial manipulation applications},

author = {J. Lee, K. K. Leang, W. Yim},

year  = {2018},

date = {2018-03-01},

journal = {ASME J. Mechanisms and Robotics},

volume = {10},

number = {4},

pages = {041007},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{CarricoJD_2017_IJSNM,

title = {A Comprehensive Review of Select Smart Polymeric and Gel Actuators for Soft Mechatronics Applications: Fundamentals, Free-form Fabrication, and Motion Control},

author = {J. D. Carrico, T. Tyler and K. K. Leang. },

url = {http://www.kam.k.leang.com/academics/pubs/CarricoJD_2018_IJSNM.pdf},

year  = {2018},

date = {2018-02-07},

journal = {Invited article to the Special Issue on Active Materials and Soft Mechatronics, International Journal of Smart and Nano Materials},

volume = {8},

number = {4},

pages = {144-213},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{TanX_2017_IJIRA,

title = {Guest Editorial: Focused Section on Advances in Soft Robotics},

author = {X. Tan, K. K. Leang and Z. Yin},

year  = {2017},

date = {2017-04-08},

journal = {International Journal of Intelligent Robotics and Applications},

volume = {1},

number = {2},

pages = {121 - 123},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{WangH_2017,

title = {Adaptive Vision-Based Leader- Follower Formation Control of Mobile Robots},

author = {H. Wang, D. Guo, X. Liang, W. Chen, G. Hu and K.K. Leang},

url = {http://ieeexplore.ieee.org/document/7752961/},

year  = {2017},

date = {2017-03-23},

journal = { IEEE Transactions on Industrial Electronics},

volume = {64},

number = {4},

pages = {2893 - 2902},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{DejunG_2016a,

title = {Adaptive-Repetitive Visual-Servo Control of Low-Flying Aerial Robots via Uncalibrated High-Flying Cameras},

author = {D. Guo, J. Bourne, H. Wang, W. Yim and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/DejunG_2017a_JNS.pdf},

year  = {2017},

date = {2017-03-22},

journal = { Journal of Nonlinear Science, Special issue on robotics: mechanics and control of locomotion},

volume = {27},

number = {4},

pages = {1235-1256},

abstract = {This paper presents the design and implementation of an adaptive-repetitive visual-servo control system for a moving high-flying vehicle (HFV) with an uncalibrated camera to monitor, track, and precisely control the movements of a low-flying vehicle (LFV) or mobile ground robot. Applications of this control strategy include the use of high-flying unmanned aerial vehicles (UAVs) with computer vision for monitoring, controlling, and coordinating the movements of lower altitude agents in areas, for example, where GPS signals may be unreliable or nonexistent. When deployed, a remote operator of the HFV defines the desired trajectory for the LFV in the HFV’s camera frame.Due to the circular motion of the HFV, the resulting motion trajectory of the LFV in the image frame can be periodic in time, thus an adaptive-repetitive control system is exploited for regulation and/or trajectory tracking. The adaptive control law is able to handle uncertainties in the camera’s intrinsic and extrinsic parameters. The design and stability analysis of the closed-loop control system is presented, where Lyapunov stability is shown. Simulation and experimental results are presented to demonstrate the effectiveness of the method for controlling the movement of a low flying quadcopter, demonstrating the capabilities of the visual-servo control system for localization (i.e.,, motion capturing) and trajectory tracking control. In fact, results show that the LFV can be commanded to hover in place as well as track a user-defined flower-shaped closed trajectory, while the HFV and camera system circulates above with constant angular velocity. On average, the proposed adaptive-repetitive visual-servo control system reduces the average RMS tracking error by over 77% in the image plane and over 71% in the world frame compared to using just the adaptive visual-servo control law.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{wangH_2017b,

title = {Eye-in-Hand Tracking Control of a Free-Floating Space Manipulator},

author = {H. Wang, D. Guo, H. Xu, W. Chen, T. Liu and K. K. Leang,},

year  = {2017},

date = {2017-03-01},

journal = {IEEE Transactions on Aerospace and Electronic Systems},

volume = {53},

number = {4},

pages = {1855 - 1865},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{BareissD_2017a,

title = {On-Board Model-Based Automatic Collision Avoidance: Application in Remotely Piloted Unmanned Aerial Vehicles},

author = {D. Bareiss, J. Bourne, K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/BareissD_2017.pdf

http://www.kam.k.leang.com/academics/autonomous-robots-2017/},

year  = {2017},

date = {2017-02-01},

journal = {Autonomous robots},

volume = {41},

number = {7},

pages = {1539-1554},

abstract = {This paper focuses on real-world implementation and verification of a local, model-based stochastic automatic collision avoidance algorithm, with application in remotely-piloted (tele-operated) unmanned aerial vehicles (UAVs). Automatic collision detection and avoidance for tele-operated UAVs can reduce the workload of pilots to allow them to focus on the task at hand, such as searching for victims in a search and rescue scenario following a natural disaster. The proposed algorithm takes the pilot's input and exploits the robot's dynamics to predict the robot's trajectory for determining whether a collision will occur. Using on-board sensing for obstacle detection, if a collision is imminent, the algorithm modifies the pilot's input to avoid the collision while attempting to maintain the pilot's intent. The algorithm is implemented using a low-cost on-board computer, fight-control system, and a two-dimensional laser illuminated detection and ranging (LIDAR) sensor for obstacle detection along the trajectory of the robot. The sensor data is processed using a split-and-merge segmentation algorithm and an approximate Minkowski difference. Results from flight tests demonstrate the algorithm's capabilities for tele-operated collision-free control of an experimental UAV.  For videos related to this work, please look here: http://www.kam.k.leang.com/academics/autonomous-robots-2017/},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{SahuB_2015,

title = {Design and Analysis of Scanning Probe Microscopy Cantilevers with Microthermal Actuation},

author = { B. Sahu and R. Riddle and D. Ross and M. Sheplak and K. K. Leang and C. R. Taylor},

year  = {2015},

date = {2015-12-01},

journal = {IEEE Journal of Microelectromechanical Systems},

volume = {24},

number = {6},

pages = {1768 - 1781},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{CarricoJD_2015b,

title = {Fused filament 3D printing of ionic polymer-metal composites (IPMCs)},

author = {James D. Carrico, Nick W. Traeden, Matteo Aureli and Kam K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/CarricoJD_2015b.pdf},

doi = {doi:10.1088/0964-1726/24/12/125021},

year  = {2015},

date = {2015-11-08},

journal = {Smart Materials and Structures},

volume = {24},

pages = {125021 (11 pages)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{FlemingAJ_2015a,

title = {Low-order damping and tracking control for scanning probe systems},

author = {A. J. Fleming, Y. R. Teo and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/FlemingAJ_2015a.pdf},

doi = {10.3389/fmech.2015.00014},

year  = {2015},

date = {2015-10-24},

journal = {Mechatronics, Frontiers in Mechanical Engineering},

volume = {1},

pages = {Article 14},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{EielsenAA_2015,

title = {Low-order Continuous-time Robust Repetitive Control: Application in Nanopositioning},

author = { A. A. Eielsen and J. T. Gravdahla and K. K. Leang},

year  = {2015},

date = {2015-09-01},

journal = {Mechatronics},

volume = {30},

pages = {231–243},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{TsugawaMA_2015,

title = {Slender tube-shaped and square rod-shaped IPMC actuators with integrated sensing for soft mechatronics},

author = {M. A. Tsugawa, V. Palmre, J. D. Carrico, K. J. Kim and K. K. Leang},

year  = {2015},

date = {2015-06-16},

journal = {Meccanica},

volume = {50},

number = {11},

pages = {2781-2795},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{PalmreV_2014,

title = {Nanothorn electrodes for ionic polymer-metal composite artificial muscles},

author = { V. Palmre and D. Pugal and K. J. Kim and K. K. Leang and K. Asaka and A. Aabloo},

url = {http://www.kam.k.leang.com/academics/pubs/PalmreV_2014.pdf},

year  = {2014},

date = {2014-09-17},

journal = {Scientific Reports},

volume = {4},

number = {6176},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{HubbardJJ_2013,

title = {Monolithic IPMC fins for propulsion and maneuvering in bio-inspired underwater robotics},

author = { J. J. Hubbard and M. Fleming and V. Palmre and D. Pugal and K. J. Kim and K. K. Leang},

url = {http://kam.k.leang.com/academics/pubs/HubbardJJ_2014.pdf},

year  = {2014},

date = {2014-07-10},

journal = {IEEE Journal of Oceanic Engineering},

volume = {39},

number = {3},

pages = {540 - 551},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ClaytonGC_2014a,

title = {Range-based control of dual-stage nanopositioning systems},

author = { G. C. Clayton and C. J. Dudley and K. K. Leang},

url = {http://kam.k.leang.com/academics/pubs/ClaytonGM_2014a.pdf},

year  = {2014},

date = {2014-04-01},

journal = {Review of Scientific Instruments},

volume = {85},

number = {4},

pages = {045003 (6 pages)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ShanY_2013a,

title = {Mechanical design and control for high-speed nanopositioning: serial-kinematic nanopositioners and repetitive control for nanofabrication},

author = { Y. Shan and K. K. Leang},

url = {http://kam.k.leang.com/academics/pubs/ShanY_2013a.pdf},

year  = {2013},

date = {2013-01-01},

journal = {IEEE Control Systems Magazine (In press), Special Issue on Dynamics and Control of Micro and Naoscale Systems},

volume = {33},

number = {6},

pages = {86 -- 105},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{PalmreV_2013,

title = {An IPMC-enabled bio-inspired bending/twisting fin for underwater applications},

author = { V. Palmre and M. Fleming and J. J. Hubbard and D. Pugal and S. Kim and K. J. Kim and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/PalmreV_2013.pdf},

year  = {2013},

date = {2013-01-01},

journal = {Smart Mater. Struct.},

volume = {22},

pages = {014003},

abstract = {This paper discusses the design, fabrication, and characterization of an ionic polymer–metal composite (IPMC) actuator-based bio-inspired active fin capable of bending and twisting motion. It is pointed out that IPMC strip actuators are used in the simple cantilever configuration to create simple bending (flapping-like) motion for propulsion in underwater autonomous systems. However, the resulting motion is a simple 1D bending and performance is rather limited. To enable more complex deformation, such as the flapping (pitch and heaving) motion of real pectoral and caudal fish fins, a new approach which involves molding or integrating IPMC actuators into a soft boot material to create an active control surface (called a ‘fin’) is presented. The fin can be used to realize complex deformation depending on the orientation and placement of the actuators. In contrast to previously created IPMCs with patterned electrodes for the same purpose, the proposed design avoids (1) the

more expensive process of electroless plating platinum all throughout the surface of the actuator and (2) the need for specially patterning the electrodes. Therefore, standard shaped IPMC actuators such as those with rectangular dimensions with varying thicknesses can be used. One unique advantage of the proposed structural design is that custom shaped fins and control surfaces can be easily created without special materials processing. The molding process is cost effective and does not require functionalizing or ‘activating’ the boot material similar to creating IPMCs. For a prototype fin (90-mm wide x 60-mm long x 1.5-mm thick), the measured maximum tip displacement was approximately 44 mm and the twist angle of the fin exceeded 10. Lift and drag measurements in water where the prototype fin with an airfoil profile was dragged through water at a velocity of 21 cm/s showed that the lift and drag forces can be affected by controlling the IPMCs embedded into the fin structure.  These results suggest that such IPMC-enabled fin designs can be used for developing active propeller blades or control surfaces on underwater vehicles.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{LeangKK_2013b,

title = {Matlab tricks and tips},

author = { K. K. Leang},

year  = {2013},

date = {2013-01-01},

journal = {IEEE Cont. Syst. Mag.},

volume = {33},

number = {4},

pages = {39 -- 40},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{LeangKK_2012c,

title = {Integrated sensing for IPMC actuators using strain gages for underwater applications},

author = { K. K. Leang and Y. Shan and S. Song and K. J. Kim},

year  = {2012},

date = {2012-01-01},

journal = {IEEE/ASME Trans. Mechatronics},

volume = {17},

number = {2},

pages = {345 -- 355},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ShanY_2012a,

title = {Dual-stage repetitive control with Prandtl-Ishlinskii hysteresis inversion for piezo-based nanopositioning},

author = { Y. Shan and K. K. Leang},

url = {http://kam.k.leang.com/academics/pubs/ShanY_2012a.pdf},

year  = {2012},

date = {2012-01-01},

journal = {Mechatronics},

volume = {22},

pages = {271 -- 281},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{YongY_2012,

title = {Invited Review: High-speed flexure-guided nanopositioning: mechanical design and control Issues},

author = { Y. Yong and S. O. R. Moheimani and B. J. Kenton and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/YongYK_2012.pdf},

year  = {2012},

date = {2012-01-01},

journal = {Review of Scientific Instruments},

volume = {83},

number = {12},

pages = {121101},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ShanY_2012b,

title = {Accounting for hysteresis in repetitive control design: nanopositioning example},

author = { Y. Shan and K. K. Leang},

url = {http://kam.k.leang.com/academics/pubs/ShanY_2012b.pdf},

year  = {2012},

date = {2012-01-01},

journal = {Automatica},

volume = {48},

number = {8},

pages = {1751 -- 1758},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{KentonBJ_2012,

title = {Design and control of a three-axis serial-kinematic high-bandwidth nanopositioner},

author = { B. J. Kenton and K. K. Leang},

url = {http://kam.k.leang.com/academics/pubs/KentonBJ_2012a.pdf},

year  = {2012},

date = {2012-01-01},

journal = {IEEE/ASME Trans. Mechatronics},

volume = {17},

number = {2},

pages = {356 -- 369},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{FuH_2012a,

title = {Teaching the difference between stiffness and damping},

author = { H. Fu and K. K. Leang},

year  = {2012},

date = {2012-01-01},

journal = {IEEE Cont. Syst. Mag.},

volume = {32},

number = {4},

pages = {95 -- 97},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{KimKJ_2012h,

title = {Introduction to part 2 of the themed articles on ionic polymer-metal composites},

author = { K. J. Kim and K. K. Leang},

year  = {2012},

date = {2012-01-01},

journal = {International Journal of Smart and Nano Materials},

volume = {3},

number = {4},

pages = {243},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{KimKJ_2012a,

title = {Introduction to the themed articles on ionic polymer-metal composites},

author = { K. J. Kim and K. K. Leang},

year  = {2012},

date = {2012-01-01},

journal = {International Journal of Smart and Nano Materials},

volume = {3},

number = {3},

pages = {183 -- 187},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{LeangKK_2012b,

title = {Short online videos to excite and engage students about control},

author = { K. K. Leang},

year  = {2012},

date = {2012-01-01},

journal = {IEEE Cont. Syst. Mag.},

volume = {32},

number = {2},

pages = {70 -- 71},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{FlemingMJ_2012c,

title = {Mitigating IPMC back relaxation through feedforward and feedback control of patterned electrodes},

author = { M. J. Fleming and K. J. Kim and K. K. Leang},

year  = {2012},

date = {2012-01-01},

journal = {Smart Mater. Struct.},

volume = {21},

pages = {085002 (12 pages)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{LeangKK_2012a,

title = {An experiment for teaching students about control at the nanoscale},

author = { K. K. Leang},

year  = {2012},

date = {2012-01-01},

journal = {IEEE Cont. Syst. Mag.},

volume = {32},

number = {1},

pages = {66--68},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{KimKJ_2011b,

title = {A twistable ionic polymer-metal composite artificial muscle for marine applications},

author = { K. J. Kim and D. Pugal and K. K. Leang},

year  = {2011},

date = {2011-01-01},

journal = {Marine Technology Society Journal},

volume = {45},

number = {4},

pages = {83 -- 98},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ManeP_2011,

title = {Cyclic Energy harvesting from pyroelectric materials},

author = { P. Mane and J. Xie and K. Mossi and K. K. Leang},

year  = {2011},

date = {2011-01-01},

journal = {IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control},

volume = {58},

number = {1},

pages = {10--17},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{KentonBJ_2011b,

title = {A compact ultra-fast vertical nanopositioner for improving SPM scan speed},

author = { B. J. Kenton and A. J. Fleming and K. K. Leang},

year  = {2011},

date = {2011-01-01},

journal = {Rev. Sci. Instr.},

volume = {82},

pages = {123703},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{SahuB_2010,

title = {Emerging challenges of microactuators for nanoscale positioning, assembly, and manipulation},

author = { B. Sahu and C. R. Taylor and K. K. Leang},

year  = {2010},

date = {2010-01-01},

journal = {ASME Journal of Manufacturing Science and Engineering, Special Issue on Nanomanufacturing},

volume = {132},

number = {3},

pages = {030917 (16 pages)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{XieJ_2010,

title = {Performance of thin piezoelectric materials for pyroelectric energy harvesting},

author = { J. Xie and X. P. Mane and C. W. Green and K. M. Mossi and K. K. Leang},

year  = {2010},

date = {2010-01-01},

journal = {Journal of Intelligent Material Systems and Structures, Special issue of a selection of papers from the first ASME Smart Materials, Adaptive Structures and Intelligent Systems (SMASIS 2008) Symposium },

volume = {21},

pages = {243 -- 249},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{FlemingAJ_2010b,

title = {Integrated strain and force feedback for high performance control of piezoelectric actuators},

author = { A. J. Fleming and K. K. Leang},

year  = {2010},

date = {2010-01-01},

journal = {Sensors and Actuators: A. Physical},

volume = {161},

number = {1-2},

pages = {256 -- 265},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{LeangKK_2010,

title = {Teaching modules on modeling and control of piezoactuators for undergraduate dynamics and control and mechatronics courses},

author = { K. K. Leang and Q. Zou and G. Pannozzo},

year  = {2010},

date = {2010-01-01},

journal = {IEEE Trans. Education},

volume = {53},

number = {3},

pages = {372 -- 383},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{FlemingAJ_2010e,

title = {Bridging the gap between conventional and video-speed scanning probe microscopes},

author = { A. J. Fleming and B. J. Kenton and K. K. Leang},

year  = {2010},

date = {2010-01-01},

journal = {Ultramicroscopy},

volume = {110},

number = {9},

pages = {1205 -- 1214},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{LeangKK_2009a,

title = {Iterative and feedback control for hysteresis compensation in SMA},

author = { K. K. Leang and S. C. Ashley and G. Tchoupo},

year  = {2009},

date = {2009-01-01},

journal = {ASME J. Dyn. Syst. Meas. and Cont.},

volume = {131},

pages = {014502 (6 pages)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{LeangKK_2009d,

title = {High-speed serial-kinematic AFM scanner: design and drive considerations},

author = { K. K. Leang and A. J. Fleming},

year  = {2009},

date = {2009-01-01},

journal = {Asian Journal of Control, Special issue on Advanced Control Methods for Scanning Probe Microscopy Research and Techniques},

volume = {11},

number = {2},

pages = {144 -- 153},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ShanY_2009b,

title = {Frequency-weighted feedforward control for dynamic compensation in ionic polymer-metal composite actuators},

author = { Y. Shan and K. K. Leang},

year  = {2009},

date = {2009-01-01},

journal = {Smart Materials and Structures},

volume = {18},

number = {12},

pages = {125016 (11 pages)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{AridoganU_2009,

title = {Design and analysis of discrete-time repetitive control for scanning probe microscopes},

author = { U. Aridogan and Y. Shan and K. K. Leang},

url = {http://www.kam.k.leang.com/academics/pubs/AridoganU_2009.pdf},

year  = {2009},

date = {2009-01-01},

journal = {ASME J. Dyn. Syst. Meas. and Cont.},

volume = {131},

pages = {061103 (12 pages)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{LeangKK_2009b,

title = {Feedforward control of piezoactuators in atomic force microscope systems: inversion-based compensation for dynamics and hysteresis},

author = { K. K. Leang and Q. Zou and S. Devasia},

year  = {2009},

date = {2009-01-01},

journal = {IEEE Cont. Syst. Mag., Special Issue on Hysteresis},

volume = {29},

number = {1},

pages = {70 -- 82},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ClaytonGM_2009,

title = {A review of feedforward control approaches in nanopositioning for high speed SPM},

author = { G. M. Clayton and S. Tien and K. K. Leang and Q. Zou and S. Devasia},

year  = {2009},

date = {2009-01-01},

journal = {ASME J. Dyn. Syst. Meas. and Cont.},

volume = {131},

number = {6},

pages = {061101 (19 pages)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{FlemingAJ_2008b,

title = {Charge drives for scanning probe microscope positioning stages},

author = { A. J. Fleming and K. K. Leang},

year  = {2008},

date = {2008-01-01},

journal = {Ultramicroscopy},

volume = {108},

pages = {1551--1557},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{IamratanakulD_2008,

title = {Optimal seek-trajectory design for dual-stage systems},

author = { D. Iamratanakul and B. Jordan and K. K. Leang and S. Devasia},

year  = {2008},

date = {2008-01-01},

journal = {IEEE Trans. Cont. Sys. Tech.},

volume = {16},

number = {5},

pages = {869 -- 881},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ShanY_2008b,

title = {Low-cost noncontact infrared sensors for sub-micro-level position measurement and control},

author = { Y. Shan and J. E. Speich and K. K. Leang},

year  = {2008},

date = {2008-01-01},

journal = {IEEE/ASME Trans. on Mechatronics},

volume = {13},

number = {6},

pages = {700 -- 709},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{LeangKK_2007,

title = {Feedback-linearized inverse feedforward for creep, hysteresis, and vibration compensation in AFM piezoactuators},

author = {K. K. Leang and S. Devasia},

url = {http://www.kam.k.leang.com/academics/pubs/LeangKK_2007.pdf},

year  = {2007},

date = {2007-01-01},

journal = {IEEE Trans. Cont. Syst. Tech.},

volume = {15},

number = {5},

pages = {927 -- 935},

abstract = {In this brief, we study the design of a feedback and feedforward controller to compensate for creep, hysteresis, and vibration effects in an experimental piezoactuator system. First, we linearize the nonlinear dynamics of the piezoactuator by accounting for the hysteresis (as well as creep) using high-gain feedback control. Next, we model the linear vibrational dynamics and then invert the model to find a feedforward input to account vibration -- this process is significantly easier than considering the complete nonlinear dynamics (which combines hysteresis and vibration effects). Afterwards, the feedforward input is augmented to the feedback-linearized system to achieve high-precision high-speed positioning. We apply the method to a piezoscanner used in an experimental atomic force microscope to demonstrate the method’s effectiveness and we show significant reduction of both the maximum and root-mean-square tracking error. For example, high-gain feedback control compensates for hysteresis and creep effects, and in our case, it reduces the maximum error (compared to the uncompensated case) by over 90%. Then, at relatively high scan rates, the performance of the feedback controlled system can be improved by over 75% (i.e., reduction of maximum error) when the inversion-based feedforward input is integrated with the high-gain feedback controlled system.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{LeangKK_2006,

title = {Design of hysteresis-compensating iterative learning control for piezo positioners: application to atomic force microscopes},

author = { K. K. Leang and S. Devasia},

year  = {2006},

date = {2006-01-01},

journal = {Mechatronics},

volume = {16},

number = {3--4},

pages = {141 -- 158},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ZouQ_2004,

title = {Control issues in high-speed AFM for biological applications: collagen imaging example},

author = { Q. Zou and K. K. Leang and E. Sadoun and M. J. Reed and S. Devasia},

year  = {2004},

date = {2004-01-01},

journal = {Asian Journal of Control, Special issue on Advances in Nanotechnology Control},

volume = {6},

number = {2},

pages = {164-178},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{DeweyJS_1998,

title = {Experimental and theoretical results in output-trajectory redesign for flexible structures},

author = { J. S. Dewey and K. K. Leang and S. Devasia},

url = {http://www.kam.k.leang.com/academics/pubs/DeweyJS_1998.pdf},

year  = {1998},

date = {1998-01-01},

journal = {ASME J. Dyn. Syst., Meas., and Control},

volume = {120},

number = {4},

pages = {456-461},

keywords = {},

pubstate = {published},

tppubtype = {article}

}