In this study, a scissor jack was structurally analyzed and compared to a FEA model to study the structure of the jack. the system was simplified to a 2D system, and one of the truss members was analyzed for yielding, fatigue, and buckling.
The purpose of this project was to develop a system capable of launching projectiles at a curved trajectory. This system effectively imparts spin on projectiles, enabling controlled indirect fire for the intended use of military operations. Through this proof of concept, it was determined whether a scaled system would be a viable solution to the issue of controlled indirect fire in dense urban areas. Using a series of coaxial motors with independently controlled speeds, it was possible to alter the horizontal and vertical displacement of objects in flight.
The scope of this project is a combination of material science engineering and mechanical engineering. Overall, the main goal of this project is to develop a lightweight concrete that maintains its original strength profile. Initial research has shown that a plastic-concrete composite could create a more lightweight concrete than that made using the typical gravel aggregate for concrete, while still maintaining the physical strength that concrete is known for. This will be accomplished by varying the amount of plastic in the aggregate. If successful, this project would allow concrete to be used in applications it would typically not be suitable for.<br/>After testing the strength of the concrete specimens with varying fills of plastic aggregate it was determined that the control group experienced an average peak stress of 2089 psi, the 16.67% plastic group experienced an average peak stress of 2649 psi, the 33.3% plastic group experienced an average peak stress of 1852 psi, and the 50% plastic group experienced an average stress of 924.5 psi. The average time to reach the peak stress was found to be 12 minutes and 24 seconds in the control group, 15 minutes and 34 seconds in the 16.7% plastic group, 9 minutes and 45 seconds in the 33.3% plastic group, and 10 minutes and 58 seconds in the 50% plastic group. Taking the average of the normalized weights of the cylindrical samples it was determined that the control group weighed 14.773 oz/in, the 16.7% plastic group weighed 15 oz/in, the 33.3% plastic group weighed 14.573 oz/in, and the 50% plastic group weighed 12.959 oz/in. Based on these results it can be concluded that a small addition of plastic aggregate can be beneficial in creating a lighter, stronger concrete. The results show that a 16.7% fill ratio of plastic to rock aggregate can increase the failure time and the peak strength of a composite concrete. Overall, the experiment was successful in analyzing the effects of recycled plastic aggregate in composite concrete. <br/>Some possible future studies related to this subject material are adding aluminum to the concrete, having better molds, looking for the right consistency in each mixture, mixing for each mold individually, and performing other tests on the samples.
The scope of this project is a combination of material science engineering and<br/>mechanical engineering. Overall, the main goal of this project is to develop a lightweight<br/>concrete that maintains its original strength profile. Initial research has shown that a<br/>plastic-concrete composite could create a more lightweight concrete than that made using the<br/>typical gravel aggregate for concrete, while still maintaining the physical strength that concrete is<br/>known for. This will be accomplished by varying the amount of plastic in the aggregate. If<br/>successful, this project would allow concrete to be used in applications it would typically not be<br/>suitable for.<br/>After testing the strength of the concrete specimens with varying fills of plastic aggregate<br/>it was determined that the control group experienced an average peak stress of 2089 psi, the<br/>16.67% plastic group experienced an average peak stress of 2649 psi, the 33.3% plastic group<br/>experienced an average peak stress of 1852 psi, and the 50% plastic group experienced an<br/>average stress of 924.5 psi. The average time to reach the peak stress was found to be 12 minutes<br/>and 24 seconds in the control group, 15 minutes and 34 seconds in the 16.7% plastic group, 9<br/>minutes and 45 seconds in the 33.3% plastic group, and 10 minutes and 58 seconds in the 50%<br/>plastic group. Taking the average of the normalized weights of the cylindrical samples it was<br/>determined that the control group weighed 14.773 oz/in, the 16.7% plastic group weighed 15<br/>oz/in, the 33.3% plastic group weighed 14.573 oz/in, and the 50% plastic group weighed 12.959<br/>oz/in. Based on these results it can be concluded that a small addition of plastic aggregate can be<br/>beneficial in creating a lighter, stronger concrete. The results show that a 16.7% fill ratio of<br/>plastic to rock aggregate can increase the failure time and the peak strength of a composite<br/>concrete. Overall, the experiment was successful in analyzing the effects of recycled plastic<br/>aggregate in composite concrete.<br/>Some possible future studies related to this subject material are adding aluminum to the<br/>concrete, having better molds, looking for the right consistency in each mixture, mixing for each<br/>mold individually, and performing other tests on the samples.
The Micro-g NExT 2019 challenge set out to find a new device to replace the Apollo mission lunar contingency sampler in preparation for the 2024 Artemis mission. The 2019 challenge set a series of requirements that would enable compatibility with the new xEMU suit and enable astronauts to effectively collect and secure an initial sample upon landing. The final prototype developed by the team features a sliding plate design with each plate slightly shorter than the previous. The device utilizes the majority of the xEMU suit’s front pocket volume while still allowing space for the astronaut’s hand and the bag for the sample. Considering safety concerns, the device satisfies NASA’s requirements for manual handheld devices and poses no threat to the astronaut under standard operation. In operation, the final design experiences an acceptable level stress in the primary use direction, and an even less in the lateral direction. Using assumptions such as the depth and density of lunar soil to be sampled, the working factor of safety is about 2 for elastic deformation, but the tool can still be operated and even collapsed at roughly double that stress. Unfortunately, the scope of this thesis only covers the effectiveness of resin prototypes and simulations of aluminum models, but properly manufactured aluminum prototypes are the next step for validating this design as a successor to the design used on the Apollo missions.
The Micro-g NExT 2019 challenge set out to find a new device to replace the Apollo mission lunar contingency sampler in preparation for the 2024 Artemis mission. The 2019 challenge set a series of requirements that would enable compatibility with the new xEMU suit and enable astronauts to effectively collect and secure an initial sample upon landing. The final prototype developed by the team features a sliding plate design with each plate slightly shorter than the previous. The device utilizes the majority of the xEMU suit’s front pocket volume while still allowing space for the astronaut’s hand and the bag for the sample. Considering safety concerns, the device satisfies NASA’s requirements for manual handheld devices and poses no threat to the astronaut under standard operation. In operation, the final design experiences an acceptable level stress in the primary use direction, and an even less in the lateral direction. Using assumptions such as the depth and density of lunar soil to be sampled, the working factor of safety is about 2 for elastic deformation, but the tool can still be operated and even collapsed at roughly double that stress. Unfortunately, the scope of this thesis only covers the effectiveness of resin prototypes and simulations of aluminum models, but properly manufactured aluminum prototypes are the next step for validating this design as a successor to the design used on the Apollo missions.
The Micro-g NExT 2019 challenge set out to find a new device to replace the Apollo mission lunar contingency sampler in preparation for the 2024 Artemis mission. The 2019 challenge set a series of requirements that would enable compatibility with the new xEMU suit and enable astronauts to effectively collect and secure an initial sample upon landing. The final prototype developed by the team features a sliding plate design with each plate slightly shorter than the previous. The device utilizes the majority of the xEMU suit’s front pocket volume while still allowing space for the astronaut’s hand and the bag for the sample. Considering safety concerns, the device satisfies NASA’s requirements for manual handheld devices and poses no threat to the astronaut under standard operation. In operation, the final design experiences an acceptable level stress in the primary use direction, and an even less in the lateral direction. Using assumptions such as the depth and density of lunar soil to be sampled, the working factor of safety is about 2 for elastic deformation, but the tool can still be operated and even collapsed at roughly double that stress. Unfortunately, the scope of this thesis only covers the effectiveness of resin prototypes and simulations of aluminum models, but properly manufactured aluminum prototypes are the next step for validating this design as a successor to the design used on the Apollo missions.
The Micro-g NExT 2019 challenge set out to find a new device to replace the Apollo mission lunar contingency sampler in preparation for the 2024 Artemis mission. The 2019 challenge set a series of requirements that would enable compatibility with the new xEMU suit and enable astronauts to effectively collect and secure an initial sample upon landing. The final prototype developed by the team features a sliding plate design with each plate slightly shorter than the previous. The device utilizes the majority of the xEMU suit’s front pocket volume while still allowing space for the astronaut’s hand and the bag for the sample. Considering safety concerns, the device satisfies NASA’s requirements for manual handheld devices and poses no threat to the astronaut under standard operation. In operation, the final design experiences an acceptable level stress in the primary use direction, and an even less in the lateral direction. Using assumptions such as the depth and density of lunar soil to be sampled, the working factor of safety is about 2 for elastic deformation, but the tool can still be operated and even collapsed at roughly double that stress. Unfortunately, the scope of this thesis only covers the effectiveness of resin prototypes and simulations of aluminum models, but properly manufactured aluminum prototypes are the next step for validating this design as a successor to the design used on the Apollo missions.
Fatigue damage accumulation under multiaxial loading conditions is an important practical problem for which there is a need to collect additional experimental data to calibrate and validate models. In this work, a sample with a special geometry capable of producing biaxial stresses while undergoing uniaxial load was fabricated and tested successfully and used, along with standard dogbone samples, to monitor the evolution of surface roughness development under cyclic loading using optical microscopy. In addition, a Michelson interferometer was successfully designed, built and tested that can be used to monitor surface roughness for lower levels of load than those used in this work. Results of testing and characterization in 2024-T3 samples tested at a maximum stress slightly below their yield strength and load ratio ~ 0.1 indicate that most of the surface roughness development under cyclic loads occurs on the second half of the fatigue, with the bulk of it close to failure. However, samples with load axes perpendicular to the rolling direction showed earlier development of roughness, which correlated with shorter fatigue lives and the expected anisotropy of strength in the material.
Particle Image Velocimetry (PIV) has become a cornerstone of modern experimental fluid mechanics due to its unique ability to resolve the entire instantaneous two-dimensional velocity field of an experimental flow. However, this methodology has historically been omitted from undergraduate curricula due to the significant cost of research-grade PIV systems and safety considerations stemming from the high-power Nd-YAG lasers typically implemented by PIV systems. In the following undergraduate thesis, a low-cost model of a PIV system is designed to be used within the context of an undergraduate fluid mechanics lab. The proposed system consists of a Hele-Shaw water tunnel, a high-power LED lighting source, and a modern smartphone camera. Additionally, a standalone application was developed to perform the necessary image processing as well as to perform Particle Streak Velocimetry (PSV) and PIV image analysis. Ultimately, the proposed system costs $229.33 and can replicate modern PIV techniques albeit for simple flow scenarios.