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Full-Text Articles in Mechanical Engineering

Optimal Design And Control Of An Electromechanical Transfemoral Prosthesis With Energy Regeneration, Farbod Rohani, Hanz Richter, Antonie J. Van Den Bogert Nov 2017

Optimal Design And Control Of An Electromechanical Transfemoral Prosthesis With Energy Regeneration, Farbod Rohani, Hanz Richter, Antonie J. Van Den Bogert

Mechanical Engineering Faculty Publications

In this paper, we present the design of an electromechanical above-knee active prosthesis with energy storage and regeneration. The system consists of geared knee and ankle motors, parallel springs for each motor, an ultracapacitor, and controllable four-quadrant power converters. The goal is to maximize the performance of the system by finding optimal controls and design parameters. A model of the system dynamics was developed, and used to solve a combined trajectory and design optimization problem. The objectives of the optimization were to minimize tracking error relative to human joint motions, as well as energy use. The optimization problem was solved …


Transcutaneous Electrical Stimulation For The Production Of Functional Motion Of A Human Arm, Kyra Ruby Jan 2017

Transcutaneous Electrical Stimulation For The Production Of Functional Motion Of A Human Arm, Kyra Ruby

Undergraduate Research Posters 2017

Persons with tetraplegia experience little to no function in their arms and are therefore unable to perform reaching tasks without assistance. While functional electrical stimulation (FES) has shown promise for restoring motion to paralyzed limbs, it is limited by issues such as muscle fatigue and atrophy. A control strategy robust enough to overcome these issues has yet to be developed and some motions are not feasible even with the most sophisticated FES control strategy. In theory, a powered exoskeleton could be used in concert with an FES system to increase the accuracy of control and assist the arm when motions …


P2: Construction Of Weather Station For Measuring Wind Using A Hovering Drone Network, Adam Stead, Mark Travis, Rishi Maheshwari Jan 2017

P2: Construction Of Weather Station For Measuring Wind Using A Hovering Drone Network, Adam Stead, Mark Travis, Rishi Maheshwari

Undergraduate Research Posters 2017

Our research aims to build and test the effectiveness of the Sparkfun® Weather Station in its ability to record meaningful data while streaming to a remote device in real-time. This is motivated by our plans to utilize a hovering-drone system to collect meteorological data, such as wind speed, wind direction, humidity, pressure, and temperature. This data is essential to evaluate the wind profiles of a given area and assess available wind resource. The weather station was first calibrated by comparing measurements of the cup anemometer against a standard pitot tube in the lab. We found that the measured wind speed …


P1: Measuring Wind Using A Hovering Drone Network: Met-Masts On The Go, Mohamad Khattab, Hassan Jaroudi Jan 2017

P1: Measuring Wind Using A Hovering Drone Network: Met-Masts On The Go, Mohamad Khattab, Hassan Jaroudi

Undergraduate Research Posters 2017

Renewable energy has grown considerably over the past years, with a projected growth of $460 billion per year by 2030. One of these renewable energies is deploying wind turbines to harvest wind energy. Knowledge of wind speed and direction is critical to determine the appropriate site to place wind turbines. The current method of collecting wind data primarily by installing stationary meteorological towers is expensive and limited, because met masts are fixed once built. This research aims at using a network of hovering drones as a platform to measure wind speed, direction, temperature and humidity at multiple elevations, which could …


Development And Verification Of A Mechanical Loading Device For Microfluidics, Stefan Habean, Erin Tesny Jan 2017

Development And Verification Of A Mechanical Loading Device For Microfluidics, Stefan Habean, Erin Tesny

Undergraduate Research Posters 2017

Establishing the role that mechanics play in nerve cell (e.g. neurons) function requires experimental testing. Microfluidic based experiments are commonly used to study neuron growth and function, and studies have found mechanics to play an important role in neuron health. External loads can be applied to a microfluidic device using a motor, which presumably influences the mechanical environment of the cells. While a motor can easily apply known displacements, a “load cell” is necessary to measure corresponding forces. In an existing prototype microfluidic loading device, a load cell was integrated and verified. The manufacturer's calibration of the load cell was …


Design And Control Of A Powered Rowing Machine With Programmable Impedance, Jose Humberto De La Casas Zolezzi Jan 2017

Design And Control Of A Powered Rowing Machine With Programmable Impedance, Jose Humberto De La Casas Zolezzi

ETD Archive

Due to the rise of obesity, diabetes and cardiovascular disease, research in human performance and physical activity has received increased attention. Rowing machines are used for performance improvements through concentric exercises, however a combination of concentric and eccentric actions is known to improve the effectiveness of training. In this work, a conventional rowing machine was modified to include an electric motor and a robust impedance control system, enabling programmable impedance with concentric and eccentric capabilities. Eccentric exercises are known to contribute significantly to the efficacy of training and to diminish the detrimental effects of humans operating in microgravity for long …


Forming A Metal Matrix Nanocomposite (Mmnc) With Fully Dispersed And Deagglomerated Multiwalled Carbon Nanotubes (Mwcnts), Mahesh Kumar Pallikonda Jan 2017

Forming A Metal Matrix Nanocomposite (Mmnc) With Fully Dispersed And Deagglomerated Multiwalled Carbon Nanotubes (Mwcnts), Mahesh Kumar Pallikonda

ETD Archive

Carbon Nanotubes (CNTs) with their exceptional properties will facilitate the Metal matrix composites (MMC) to exhibit good mechanical properties, thermal and electrical conductivities, corrosion resistance, etc. The critical factor that holds the development of the Metal matrix Nanocomposites (MMNC) by using CNTs is the tendency of CNTs to form clusters (agglomerations) due to their high Van der Waals attractions. Due to this factor, low density and other properties of the CNTs, there has been a delay in harnessing their ultimate potential.
Existing literature in contemporary times from the works of few researches in Nanocomposites shows the prevalence of using surfactants …


Piv Analysis Of Wake Structure Of Real Elephant Seal Whiskers, Joseph Antun Bunjevac Jan 2017

Piv Analysis Of Wake Structure Of Real Elephant Seal Whiskers, Joseph Antun Bunjevac

ETD Archive

Seals are able to accurately detect minute disturbances in the ambient flow
environment using their whiskers, which is attributed to the exceptional capability of
their whiskers to suppress vortex-induced vibrations in the wake. To explore potential applications for designing smart flow devices, such as high-sensitivity underwater
flow sensors and drag reduction components, researchers have studied how the role
of some key parameters of whisker-like morphology affect the wake structure. Due to
the naturally presented variation in size and curvature along the length of whiskers,
it is not well understood how a real whisker changes the surrounding flow and the
vortex …


Investigation Of Extremum Seeking Control For Adaptive Exercise Machines, Brahm T. Powell Jan 2017

Investigation Of Extremum Seeking Control For Adaptive Exercise Machines, Brahm T. Powell

ETD Archive

Many muscle rehabilitation regimens are non-adaptive and recommended subjectively by physicians. While there are advantages to having the feedback of a qualified physician, utilizing real-time muscle performance feedback could be beneficial. An extremum seeking control design is proposed to fulfill the need for an automated, load-varying exercise machine that can optimize muscle performance.

Several steps are outlined to contribute to the realization of this goal. First, the extremum seeking control scheme is discussed. Second, the Hill muscle model will be described. Theoretical muscle effort extrema will be derived for selected optimization cases, namely maximizing average squared power by varying load …