Matching Items (27)
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- All Subjects: Mechanical Engineering
- Creators: Mechanical and Aerospace Engineering Program
- Member of: Theses and Dissertations
- Status: Published
Description
The goal of this honors thesis creative project was to design, manufacture and test a retrofitted E-bike kit that met certain stated design objections. To design a successful E-bike kit, the needs of the customer were researched and turned into measurable engineering requirements. For the biker, these requirements are speed, range, cost and simplicity. The approach is outlined similarly to the capstone program here at ASU. There is an introduction in sections 1 and 2 which gives the motivation and an overview of the project done. In section 3, the voice of the customer is discussed and converted into requirements. In sections 4, 5,6,7 and 8 the design process is described. Section 4 is the conceptual design where multiple concepts are narrowed down to one design. Section 5 is the preliminary design, where the design parts are specified and optimized to fit requirements. Section 6 is fabrication and assembly which gives details into how the product was manufactured and built. Sections 7 and 8 are the testing and validation sections where tests were carried out to verify that the requirements were met. Sections 9 and 10 were part of the conclusion in which recommendations and the project conclusions are depicted. In general, I produced a successful prototype. Each phase of the design came with its own issues and solutions but in the end a functioning bike was delivered. There were a few design options considered before selecting the final design. The rear-drive friction design was selected based on its price, simplicity and performance. The design was optimized in the preliminary design phase and items were purchased. The purchased items were either placed on the bike directly or had to be manufactured in some way. Once the assembly was completed, testing and validation took place to verify that the design met the requirements. Unfortunately, the prototype did not meet all the requirements. The E-bike had a maximum speed of 14.86 mph and a range of 12.75 miles which were below the performance requirements of 15 mph and 15 miles. The cost was $41.67 over the goal of $300 although the total costs remained under budget. At the end of the project, I delivered a functioning E-bike retrofitting kit on the day of the defense. While it did not meet the requirements fully, there was much room for improvement and optimization within the design.
ContributorsLangerman, Jonathon Henry (Author) / Phelan, Patrick (Thesis director) / Trimble, Steven (Committee member) / Mechanical and Aerospace Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Prosthetic sockets are a static interface for dynamic residual limbs. As the user's activity level increases, the volume of the residual limb decreases by up to 11% and increases by as much as 7% after activity. Currently, volume fluctuation is addressed by adding/removing prosthetic socks to change the profile of the residual limb. However, this is time consuming. These painful/functional issues demand a prosthetic socket with an adjustable interface that can adapt to the user's needs. This thesis presents a prototype design for a dynamic soft robotic interface which addresses this need. The actuators are adjustable depending on the user's activity level, and their structure provides targeted compression to the soft tissue which helps to limit movement of the bone relative to the socket. The engineering process was used to create this design by defining system level requirements, exploring the design space, selecting a design, and then using testing/analysis to optimize that design. The final design for the soft robotic interface meets the applicable requirements, while other requirements for the electronics/controls will be completed as future work. Testing of the prototype demonstrated promising potential for the design with further refinement. Work on this project should be continued in future research/thesis projects in order to create a viable consumer product which can improve lower limb amputee's quality of life.
ContributorsHolmes, Breanna Swift (Author) / Zhang, Wenlong (Thesis director) / Polygerinos, Panagiotis (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
This research report investigates the feasibility of using RFID in Traffic Sign Recognition (TSR) Systems for autonomous vehicles, specifically driver-less cars. Driver-less cars are becoming more prominent in society but must be designed to integrate with the current transportation infrastructure. Current research in TSR systems use image processing as well as LIDAR to identify traffic signs, yet these are highly dependent on lighting conditions, camera quality and sign visibility. The read rates of current TSR systems in literature are approximately 96 percent. The usage of RFID in TSR systems can improve the performance of traditional TSR systems. An RFID TSR was designed for the Autonomous Pheeno Test-bed at the Arizona State University (ASU) Autonomous Collective Systems (ACS) Laboratory. The system was tested with varying parameters to see the effect of the parameters on the read rate. It was found that high reader strength and low tag distance had a maximum read rate of 96.3 percent, which is comparable to existing literature. It was proven that an RFID TSR can perform as well as traditional TSR systems, and has the capacity to improve accuracy when used alongside RGB cameras and LIDAR.
ContributorsMendoza, Madilyn Kido (Author) / Berman, Spring (Thesis director) / Yu, Hongbin (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
The purpose of this project focuses on analyzing how a typically brittle material, such as PLA, can be manipulated to become deformable, through the development of an origami structure, in this case—the Yoshimuri pattern. The experimental methodology focused on creating a base Solidworks model, with varying hinge depths, and 3D printing these various models. A cylindrical shell was also developed with comparable dimensions to the Yoshimuri dimensions. These samples were then tested through compression testing, with the load-displacement, and thus the stress-strain curves are analyzed. From the results, it was found that generally, the Yoshimuri samples had a higher level of deformation compared to the cylindrical shell. Moreover, the cylindrical shell had a higher stiffness ratio, while the Yoshimuri patterns had strain rates as high as 16%. From this data, it can be concluded that by changing how the structure is created through origami patterns, it is possible to shift the characteristics of a structure even if the material properties are initially quite brittle.
ContributorsSundar, Vaasavi (Author) / Jiang, Hanqing (Thesis director) / Kingsbury, Dallas (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / School of Social Transformation (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
The traditional understanding of robotics includes mechanisms of rigid structures, which can manipulate surrounding objects, taking advantage of mechanical actuators such as motors and servomechanisms. Although these methods provide the underlying fundamental concepts behind much of modern technological infrastructure, in fields such as manufacturing, automation, and biomedical application, the robotic structures formed by rigid axels on mechanical actuators lack the delicate differential sensors and actuators associated with known biological systems. The rigid structures of traditional robotics also inhibit the use of simple mechanisms in congested and/or fragile environments. By observing a variety of biological systems, it is shown that nature models its structures over millions of years of evolution into a combination of soft structures and rigid skeletal interior supports. Through technological bio-inspired designs, researchers hope to mimic some of the complex behaviors of biological mechanisms using pneumatic actuators coupled with highly compliant materials that exhibit relatively large reversible elastic strain. This paper begins the brief history of soft robotics, the various classifications of pneumatic fluid systems, the associated difficulties that arise with the unpredictable nature of fluid reactions, the methods of pneumatic actuators in use today, the current industrial applications of soft robotics, and focuses in large on the construction of a universally adaptable soft robotic gripper and material application tool. The central objective of this experiment is to compatibly pair traditional rigid robotics with the emerging technologies of sort robotic actuators. This will be done by combining a traditional rigid robotic arm with a soft robotic manipulator bladder for the purposes of object manipulation and excavation of extreme environments.
ContributorsShuster, Eden S. (Author) / Thanga, Jekan (Thesis director) / Asphaug, Erik (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
The data and results presented in this paper are part of a continuing effort to innovate and pioneer the future of engineering. The purpose of the following is to demonstrate the mechanical buckling characteristics in stiff thin film and soft substrate systems, and the importance of controlling them. In today's engineering research, wrinkling in systems in beginning to be viewed as a means for engineering innovation rather than failure. This research is important to further progress the possible applications the technology proposes, such as flexible electronics and tunable adhesives. This work utilizes a cost efficient and relatively easy method for generating and analyzing buckled systems. Ultra violate oxidation at ambient temperatures is exploited to create a stiff thin surface on rubber like polydimethylsiloxane, and couple with strain induction wrinkles are generated. Wrinkle characteristics such as amplitude, wavelengths and wetting properties were investigated. In simple cases, trends were confirmed that increased oxidation relates to increased buckle wavelengths, and increase in strain corresponds to a decrease in wavelength. Hierarchical buckles were produced in one-dimensional systems treated with a multi-step method; these were the first to be generated in the ASU labs. Unique topographic changes were produced in two-dimensional systems treated with the same method. Honeycomb or dome like structures were noted to occur, important as they undergo a different energy-reliving configuration compared to traditional parallel buckles. The information provided characterizes many aspects of the buckle phenomena and will allow for further inquiry into specific functions utilizing the technology to continue advancements in engineering.
ContributorsValacich, Michael James (Author) / Jiang, Hanqing (Thesis director) / Yu, Hongyu (Committee member) / Teng, Ma (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2013-05
Description
In real world applications, materials undergo a simultaneous combination of tension, compression, and torsion as a result of high velocity impact. The split Hopkinson pressure bar (SHPB) is an effective tool for analyzing stress-strain response of materials at high strain rates but currently little can be done to produce a synchronized combination of these varying impacts. This research focuses on fabricating a flange which will be mounted on the incident bar of a SHPB and struck perpendicularly by a pneumatically driven striker thus allowing for torsion without interfering with the simultaneous compression or tension. Analytical calculations are done to determine size specifications of the flange to protect against yielding or failure. Based on these results and other design considerations, the flange and a complementary incident bar are created. Timing can then be established such that the waves impact the specimen at the same time causing simultaneous loading of a specimen. This thesis allows research at Arizona State University to individually incorporate all uniaxial deformation modes (tension, compression, and torsion) at high strain rates as well as combining either of the first two modes with torsion. Introduction of torsion will expand the testing capabilities of the SHPB at ASU and allow for more in depth analysis of the mechanical behavior of materials under impact loading. Combining torsion with tension or compression will promote analysis of a material's adherence to the Von Mises failure criterion. This greater understanding of material behavior can be implemented into models and simulations thereby improving the accuracy with which engineers can design new structures.
ContributorsVotroubek, Edward Daniel (Author) / Solanki, Kiran (Thesis director) / Oswald, Jay (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
The goal of this research is to compare the mechanical properties of CP-Ti and Ti-O and to understand the relationship between a material's microstructure and its response to fatigue. Titanium has been selected due to its desirable properties and applicability in several engineering fields. Both samples are polished and etched in order to visualize and characterize the microstructure and its features. The samples then undergo strain-controlled fatigue tests for several thousand cycles. Throughout testing, images of the samples are taken at zero and maximum load for DIC analysis. The DIC results can be used to study the local strains of the samples. The DIC analysis performed on the CP-Ti sample and presented in this study will be used to understand how the addition of oxygen in the Ti-O impacts fatigue response. The outcome of this research can be used to develop long-lasting, high strength materials.
ContributorsRiley, Erin Ashland (Author) / Solanki, Kiran (Thesis director) / Oswald, Jay (Committee member) / School of Art (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
This study experimentally investigated a selected methodology of mechanical torque testing of 3D printed gears. The motivation for pursuing this topic of research stemmed from a previous experience of one of the team members that propelled inspiration to quantify how different variables associated with 3D printing affect the structural integrity of the resulting piece. With this goal in mind, the team set forward with creating an experimental set-up and the construction of a test rig. However, due to restrictions in time and other unforeseen circumstances, this thesis underwent a change in scope. The new scope focused solely on determining if the selected methodology of mechanical torque testing was valid. Following the securement of parts and construction of a test rig, the team was able to conduct mechanical testing. This testing was done multiple times on an identically printed gear. The data collected showed results similar to a stress-strain curve when the torque was plotted against the angle of twist. In the resulting graph, the point of plastic deformation is clearly visible and the maximum torque the gear could withstand is clearly identifiable. Additionally, across the tests conducted, the results show high similarity in results. From this, it is possible to conclude that if the tests were repeated multiple times the maximum possible torque could be found. From that maximum possible torque, the mechanical strength of the tested gear could be identified.
ContributorsGarcia, Andres (Author) / Parekh, Mohan (Co-author) / Middleton, James (Thesis director) / Murthy, Raghavendra (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2023-05
Description
This study experimentally investigated a selected methodology of mechanical torque testing of 3D printed gears. The motivation for pursuing this topic of research stemmed from a previous experience of one of the team members that propelled inspiration to quantify how different variables associated with 3D printing affect the structural integrity of the resulting piece. With this goal in mind, the team set forward with creating an experimental set-up and the construction of a test rig. However, due to restrictions in time and other unforeseen circumstances, this thesis underwent a change in scope. The new scope focused solely on determining if the selected methodology of mechanical torque testing was valid. Following the securement of parts and construction of a test rig, the team was able to conduct mechanical testing. This testing was done multiple times on an identically printed gear. The data collected showed results similar to a stress-strain curve when the torque was plotted against the angle of twist. In the resulting graph, the point of plastic deformation is clearly visible and the maximum torque the gear could withstand is clearly identifiable. Additionally, across the tests conducted, the results show high similarity in results. From this, it is possible to conclude that if the tests were repeated multiple times the maximum possible torque could be found. From that maximum possible torque, the mechanical strength of the tested gear could be identified.
ContributorsParekh, Mohan (Author) / Garcia, Andres (Co-author) / Middleton, James (Thesis director) / Murthy, Raghavendra (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2023-05