@inproceedings{MRL_AFM_Flexure_Nanopositioning_Methodology,

title = {Integrated Design and Control of Flexure-Based Nanopositioning Systems — Part I: Methodology},

author = {Vijay Shilpiekandula and Kamal Youcef-Toumi},

url = {https://www.sciencedirect.com/science/article/pii/S1474667016451232},

doi = {https://doi.org/10.3182/20110828-6-IT-1002.03796},

issn = {1474-6670},

year  = {2011},

date = {2011-09-01},

journal = {IFAC Proceedings Volumes},

volume = {44},

number = {1},

pages = {9406-9412},

publisher = {IFAC},

abstract = {Abstract 

Flexure-based mechanisms, also referred to as flexures, are widely being used as motion-guidance, or bearing, elements in applications requiring multi-degree-of-freedom positioning and alignment. Unlike friction-bearings (such as sliding or rolling contact bearings), flexures can be designed to offer, to a large extent, reliable linear elastic motion with a high resolution (on the order of nanometers) over small ranges of motion (on order of micrometers). Example applications include positioning a probe or sample in atomic force microscopy, alignment of tool and sample in stamping processes, and fine-positioning of wafers and masks in semiconductor manufacturing. These applications are often required satisfy critical functional requirements, such as load-capacity, bandwidth, resolution, and range. A systematic approach is needed to simultaneously address the design and control challenges involved, starting from the initial design concept generation stage to the final control implementation and testing. In this paper, we present an integrated design and control method for implementing flexure-based nanopositioning systems. We discuss the need for varying design topology and order of a controller in design and control optimization. An automation engine generates a set of flexure-based design topologies and also controllers of varying order in the optimization. A simple 1-DOF example is worked out to illustrate the steps involved in using this methodology. The outcome of the exercise is a novel design topology, with it shape and size optimized, and a controller synthesized such that a desired control bandwidth and design requirements of strength and modal separation are met.},

note = {18th IFAC World Congress},

keywords = {Control Theory, Mechatronic Design, Nanotechnology, Physical System Modeling, Robot operated modular fixtures, Simulation},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{MRL_DDL_Actuator_Sizing_Pendulum,

title = {Actuator sizing of a quadruple pendulum for advanced gravitational wave detectors},

author = {Brett Shapiro and Nergis Mavalvala and Kamal Youcef-Toumi},

url = {https://ieeexplore.ieee.org/document/5991170},

doi = {10.1109/ACC.2011.5991170},

isbn = {978-1-4577-0081-1},

year  = {2011},

date = {2011-08-18},

booktitle = {Proceedings of the 2011 American Control Conference},

pages = {1358-1363},

publisher = {ACC},

organization = {ACC},

abstract = {The Laser Interferometer Gravitational-Wave Observatory (LIGO) has begun a major set of upgrades to reach a sensitivity better than 10-19 m/√(Hz) in the 10 Hz to 10 kHz frequency band. This advance is expected to bring gravitational wave observations of relativistic astrophysical events such as black hole mergers and supernovae into the realm of regular astronomy. These upgrades require complex vibration isolation systems to better decouple the test masses from ground disturbances. These high performance systems require correspondingly more complex and aggressive active control loops to meet the increased demand in instrument sensitivity. Appropriately sized actuators are essential to achieving the necessary control performance while limiting the cost, noise, and complexity associated with larger actuators. This paper applies the plant's pseudoinverse transfer function to analyze the least squares dynamic range required by the actuators to reject the stochastic disturbances exciting the Advanced LIGO quadruple pendulum isolation systems.},

keywords = {Control Theory, Data-driven learning for intelligent machine maintanence, Experimentation, Fabrication, intelligent systems, Physical System Modeling, Simulation},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{MRL_AFM_GAG_Depletion,

title = {The effect of GAG depletion on cartilage nanoscale hydraulic permeability},

author = {Tavakoli H Nia and L Han and Y Li and Soltani I Bozchalooi and H Hung and E Frank and K Youcef-Toumi and A Grodzinsky and C Orti},

url = {http://www.ors.org/Transactions/58/0282.pdf},

doi = {10.1109/ACC.2012.6315281},

isbn = {978-1-4577-1096-4},

year  = {2011},

date = {2011-01-01},

booktitle = {ORS 2012 Annual Meeting},

pages = {0282},

publisher = {ORS},

organization = {ORS},

abstract = {The advent of new time-dependent nanomechanical methods has recently enabled the quantification of cartilage tissue poroelasticity and hydraulic permeability, k, at the nanoscale [1-3] and holds great potential for early detection of pathological changes and diagnosis of osteoarthritis (OA). It is known that at the macroscale, tissue hydraulic permeability can undergo several order-of-magnitude changes due to OA [4] while the equilibrium stiffness may vary by only a factor of 2 [5]. This is because GAG chains are the main determinant of the pore size (consequently, hydraulic permeability) of cartilage while they contribute only partially to the compression stiffness of the tissue. Here, we extend the technique of atomic force microscope-based dynamic oscillatory nanoindentation to a larger frequency range (1-10,000 Hz) and compare these data to finite element analysis simulations to study the effect of GAG content, relevant to early stage OA.},

keywords = {Control Theory, Instrumentation, Nanoscale video imaging for dynamic process visualization, Nanotechnology, Physical System Modeling, Simulation},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{MRL_BRF_Multi_DOF_Stingray,

title = {A soft body under-actuated approach to multi degree of freedom biomimetic robots: A stingray example},

author = {Pablo Valdivia y Alvarado and Stephanie Chin and Winston Larson and Anirban Mazumdar and Kamal Youcef-Toumi},

url = {https://ieeexplore.ieee.org/document/5627803},

doi = {10.1109/BIOROB.2010.5627803},

isbn = {978-1-4244-7709-8},

year  = {2010},

date = {2010-11-11},

booktitle = {2010 3rd IEEE RAS EMBS International Conference on Biomedical Robotics and Biomechatronics},

pages = {473-478},

publisher = {IEEE},

organization = {IEEE},

abstract = {In this paper we present a new application of the methodology our group is developing to design and prototype under-actuated biomimetic robots by determining appropriate body material property distributions. When excited, flexible bodies with proper anisotropic material distributions display modes of vibration that mimic required locomotion kinematics and require minimal actuation. Our previous prototypes explored simple two dimensional applications for fish-like swimming. In this paper, the three dimensional vibrational kinematics of a stingray are explored. A simple design is explained, and corresponding prototypes are presented along with preliminary performance data. Our methodology shows great promise to develop simple, robust, and inexpensive mobile robots that can efficiently accomplish locomotion.},

keywords = {Biomimetic robotic fish for underwater monitoring, Experimentation, Mechatronic Design, Physical System Modeling, Robotics and Automation, Simulation, Visualization},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{MRL_WDP_Acoustic_Leak_Signals,

title = {In-pipe Acoustic Characterization of Leak Signals in Plastic Water-filled Pipes},

author = {Dimitris M Chatzigeorgiou and Sumeet Kumar and Atia E Khalifa and Ajay Deshpande and Kamal Youcef-Toumi and Sanjay Sarma and Rached Ben-Mansour},

url = {https://www.researchgate.net/publication/277303127_In-pipe_Acoustic_Characterization_of_Leak_Signals_in_Plastic_Water-filled_Pipes},

year  = {2010},

date = {2010-01-01},

booktitle = {AWWA Annual Conference and Exposition (ACE) 2010},

publisher = {AWWA},

organization = {AWWA},

abstract = {Acoustic emissions can be sensed to identify and localize leaks in water pipes. Leak noise correlators and listening devices have been reported in literature as successful approaches to leak detection but they have practical limitations in terms of cost, sensitivity, reliability and scalability. A possible efficient solution is the development of an in-pipe traveling leak detection system. It has been reported that in-pipe sensing is more accurate and efficient since the sensing element can be very close to the sound source. Currently in-pipe approaches are limited to large leaks and larger diameter pipes. Development of such a system requires clear understanding of acoustic signals generated from leaks and their variation with different pipe loading conditions, leak sizes and surrounding media. This paper discusses the acoustic characterization of leak signals in controlled environments. A lab experimental setup was designed and built in which measurements were taken from inside 4 inch PVC water pipes using a hydrophone. Signals were collected for a wide range of conditions: different pressures and leak flow rates to better understand the leak signal signatures. Experiments were conducted with different pipe connecting elements like valves and junctions, and different external conditions such as pipes placed in water, air and soil. Signals were collected at various distances from the leak location (upstream and downstream) to understand the opportunities of spatial cross-correlation techniques in localizing leaks and the effect of sensor position on the signal. Characterizations of different datasets are presented in frequency domain. The implications of acoustic characterization on the design of algorithms for leak detection are discussed and a simple algorithm to decide whether or not a leak is present near the sensor location is proposed, based on signal power calculations. The characterization gives insights, which will pave ways for the development of smart, autonomous pipe-traversing systems capable of detecting and localizing leaks on a city level water distribution network.},

keywords = {Algorithms, Computational Intelligence, Inspection; repair and intelligence for water distribution pipes, Physical System Modeling, Robotics & Automation, Simulation, Visualization},

pubstate = {published},

tppubtype = {inproceedings}

}