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Frequency response characteristics of respiratory flow-meters

Description

Flow measurement has always been one of the most critical processes in many industrial and clinical applications. The dynamic behavior of flow helps to define the state of a process. An industrial example would be that in an aircraft, where the rate of airflow passing the aircraft is used to…

Flow measurement has always been one of the most critical processes in many industrial and clinical applications. The dynamic behavior of flow helps to define the state of a process. An industrial example would be that in an aircraft, where the rate of airflow passing the aircraft is used to determine the speed of the plane. A clinical example would be that the flow of a patient's breath which could help determine the state of the patient's lungs. This project is focused on the flow-meter that are used for airflow measurement in human lungs. In order to do these measurements, resistive-type flow-meters are commonly used in respiratory measurement systems. This method consists of passing the respiratory flow through a fluid resistive component, while measuring the resulting pressure drop, which is linearly related to volumetric flow rate. These types of flow-meters typically have a low frequency response but are adequate for most applications, including spirometry and respiration monitoring. In the case of lung parameter estimation methods, such as the Quick Obstruction Method, it becomes important to have a higher frequency response in the flow-meter so that the high frequency components in the flow are measurable. The following three types of flow-meters were: a. Capillary type b. Screen Pneumotach type c. Square Edge orifice type To measure the frequency response, a sinusoidal flow is generated with a small speaker and passed through the flow-meter that is connected to a large, rigid container. True flow is proportional to the derivative of the pressure inside the container. True flow is then compared with the measured flow, which is proportional to the pressure drop across the flow-meter. In order to do the characterization, two LabVIEW data acquisition programs have been developed, one for transducer calibration, and another one that records flow and pressure data for frequency response testing of the flow-meter. In addition, a model that explains the behavior exhibited by the flow-meter has been proposed and simulated. This model contains a fluid resistor and inductor in series. The final step in this project was to approximate the frequency response data to the developed model expressed as a transfer function.

ContributorsHu, Jianchen (Author) / Macia, Narciso (Thesis advisor) / Pollat, Scott (Committee member) / Rogers, Bradley (Committee member) / Arizona State University (Publisher)

Created2013

A Guide to Speech Recognition Algorithms

Description

Many tasks that humans do from day to day are taken for granted in term of appreciating their true complexity. Humans are the only species on the planet that have developed such an in-depth means of auditory communication. Recreating the mechanisms in the brain that recognize speech patterns is no…

Many tasks that humans do from day to day are taken for granted in term of appreciating their true complexity. Humans are the only species on the planet that have developed such an in-depth means of auditory communication. Recreating the mechanisms in the brain that recognize speech patterns is no easy task. This paper compares and contrasts various algorithms used in modern day ASR systems, and focuses primarily on ASR systems in resource constrained environments. The Green colored blocks in Figure 1 will be focused on in greater detail throughout this paper, they are the key to building an exceptional ASR system. Deep Neural Networks (DNNs) are the clear and current leader among ASR technologies; all research in this field is currently revolving around this method. Although DNNs are very effective, many older methods of ASR are used often due to the complexities involved with DNNs; these difficulties include the large amount of hardware resources as well as development resources, such as engineers and money, required for this method.

ContributorsPetersen, Casey Alexander (Author) / Csavina, Kristine (Thesis director) / Pollat, Scott (Committee member) / Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)

Created2015-12

Design of a Cable Driven Drone for Perching

Description

The researchers build a drone with a grasping mechanism to wrap around branches to perch. The design process and methodology are discussed along with the software and hardware configuration. The researchers explain the influences on the design and the possibilities for what it could inspire.

ContributorsDowney, Matthew Evan (Co-author) / Macias, Jose (Co-author) / Goldenberg, Edward (Co-author) / Zhang, Wenlong (Thesis director) / Aukes, Daniel (Committee member) / Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)

Created2021-05

Design of a Cable Driven Drone for Perching

Description

The researchers build a drone with a grasping mechanism to wrap around branches to perch. The design process and methodology are discussed along with the software and hardware configuration. The researchers explain the influences on the design and the possibilities for what it could inspire.

ContributorsGoldenberg, Edward Bradley (Co-author) / Macias, Jose Carlos (Co-author) / Downey, Matthew (Co-author) / Zhang, Wenlong (Thesis director) / Aukes, Daniel M. (Committee member) / Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)

Created2021-05

Design of a Cable Driven Drone for Perching

Description

The majority of drones are extremely simple, their functions include flight and sometimes recording video and audio. While drone technology has continued to improve these functions, particularly flight, additional functions have not been added to mainstream drones. Although these basic functions serve as a good framework for drone designs, it…

The majority of drones are extremely simple, their functions include flight and sometimes recording video and audio. While drone technology has continued to improve these functions, particularly flight, additional functions have not been added to mainstream drones. Although these basic functions serve as a good framework for drone designs, it is now time to extend off from this framework. With this Honors Thesis project, we introduce a new function intended to eventually become common to drones. This feature is a grasping mechanism that is capable of perching on branches and carrying loads within the weight limit. This concept stems from the natural behavior of many kinds of insects. It paves the way for drones to further imitate the natural design of flying creatures. Additionally, it serves to advocate for dynamic drone frames, or morphing drone frames, to become more common practice in drone designs.

ContributorsMacias, Jose Carlos (Co-author) / Goldenberg, Edward Bradley (Co-author) / Downey, Matthew (Co-author) / Zhang, Wenlong (Thesis director) / Aukes, Daniel (Committee member) / Human Systems Engineering (Contributor) / Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)

Created2021-05

Manna: An Autonomously Guided Parachute Delivery System

Description

Mission aviation groups operate aircraft in areas with limited infrastructure. Existing airdrop methods pose significant risk due to their lack of steerability. This thesis details the development of Manna, a system built to address these concerns. Manna provides an automated, low cost, safe steerable delivery platform, through a custom designed…

Mission aviation groups operate aircraft in areas with limited infrastructure. Existing airdrop methods pose significant risk due to their lack of steerability. This thesis details the development of Manna, a system built to address these concerns. Manna provides an automated, low cost, safe steerable delivery platform, through a custom designed parafoil and guidance unit. Flight tests and simulations show that Manna can provide a safer alternative for critical air deliveries.

ContributorsSchlichting, Audrey (Author) / Severinghaus, Lukas (Co-author) / Wende, Anthony (Thesis director) / Delp, Deana (Committee member) / Takahashi, Timothy (Committee member) / Barrett, The Honors College (Contributor) / Aviation Programs (Contributor) / Engineering Programs (Contributor)

Created2023-05

Manna: An Autonomously Guided Parachute Delivery System

Description

Mission aviation groups operate aircraft in areas with limited infrastructure. Existing airdrop methods pose significant risk due to their lack of steerability. This thesis details the development of Manna, a system built to address these concerns. Manna provides an automated, low cost, safe steerable delivery platform, through a custom designed…

Mission aviation groups operate aircraft in areas with limited infrastructure. Existing airdrop methods pose significant risk due to their lack of steerability. This thesis details the development of Manna, a system built to address these concerns. Manna provides an automated, low cost, safe steerable delivery platform, through a custom designed parafoil and guidance unit. Flight tests and simulations show that Manna can provide a safer alternative for critical air deliveries.

ContributorsSeveringhaus, Lukas (Author) / Schlichting, Audrey (Co-author) / Wende, Anthony (Thesis director) / Delp, Deana (Committee member) / Takahashi, Timothy (Committee member) / Barrett, The Honors College (Contributor) / Engineering Programs (Contributor)

Created2023-05

Social Insect-Inspired Behaviors for Collective Search Operations by Unmanned Aerial Vehicle (UAV) Swarms

Description

A swarm of unmanned aerial vehicles (UAVs) has many potential applications including disaster relief, search and rescue, and area surveillance. A critical factor to a UAV swarm’s success is its ability to collectively locate and pursue targets determined to be of high quality with minimal and decentralized communication. Prior work…

A swarm of unmanned aerial vehicles (UAVs) has many potential applications including disaster relief, search and rescue, and area surveillance. A critical factor to a UAV swarm’s success is its ability to collectively locate and pursue targets determined to be of high quality with minimal and decentralized communication. Prior work has investigated nature-based solutions to this problem, in particular the behavior of honeybees when making decisions on future nest sites. A UAV swarm may mimic this behavior for similar ends, taking advantage of widespread sensor coverage induced by a large population. To determine whether the proven success of honeybee strategies may still be found in UAV swarms in more complex and difficult conditions, a series of simulations were created in Python using a behavior modeled after the work of Cooke et al. UAV and environmental properties were varied to determine the importance of each to the success of the swarm and to find emergent behaviors caused by combinations of variables. From the simulation work done, it was found that agent population and lifespan were the two most important factors to swarm success, with preference towards small teams with long-lasting UAVs.

ContributorsGao, Max (Author) / Berman, Spring (Thesis director) / Pavlic, Theodore (Committee member) / Barrett, The Honors College (Contributor) / College of Integrative Sciences and Arts (Contributor) / Engineering Programs (Contributor)

Created2023-05

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