3D Printer Design

3D Printer Design

3D Printer Design Designs are conceptualized to create a functional, budget-conscious 3D printer. In the spring of 2014, Nathan and a team of three colleagues at UofT were given the task of conceptualizing a relatively inexpensive 3D printer as part of a course project. The primary function of any hobbyist PLA or ABS plastic 3D printer is to extrude successive layers of molten material, beginning at the base and finishing at the top, to form the desired 3D-printed object. His team researched existing 3D printing technology, both currently on the market and hobbyist-created. As somewhat of a product benchmarking exercise, this allowed the team to get a gauge on the types of strategies that hobbyists and companies used to manufacture their components, as well as the types of features that the average printer might possess. Nathan began by selecting the materials to be used and each individual component’s dimensions such that they adhered to operational, cost and tolerancing constraints. Prior to any time spent on CAD, how individual components would interface and be assembled was fleshed out through the use of rough sketches. Nathan then modeled and assembled each of the design’s components using Solidworks software. Special consideration went towards material weight, speed & fluidity of movement, and every decision’s inevitable material and production costs. Nathan worked with his teammates to form tolerancing and functional calculations validating that the design would perform to the degree required, and a final conceptual product design was soon reached. The team collectively presented a final report, where the utilization of individual components, materials, processes, etc. were discussed and...
Client Design Proposal

Client Design Proposal

Client Design Proposal Leading a team of colleagues to create a preliminary design proposal for a client, who required a modern automobile safety system. In this project, Nathan and five colleagues were assigned Mehdi Saffarian as a client. Mehdi Saffarian is a researcher in the Human Factors and Applied Statistics Lab at the University of Toronto. Upon an initial meeting with Mehdi, he stated that he required a design that would aid in assisting elderly drivers by improving their abilities and senses required to operate a standard automotive vehicle. Nathan was elected team leader and was therefore responsible for managing the design team and arranging subsequent meetings with Mehdi. The team started by consulting factors and situations around the elderly and driving. First, they determined factors that negatively affect driving performance with age. This included loss of vision, hearing, cognitive ability, motor skills, height and bad posture. They also consulted research to determine the types and environment of the accidents that the elderly are typically in. The stakeholders involved in the creation of the design were carefully reviewed, as well as the design’s functions, team’s objectives, applicable constraints, the service environment, and of course, any and all ethics and values associated with the client and users of the new design. Nathan was responsible for outlining the problem statement, constructing an executive summary of the design process, identifying the key functions of the design, and providing a detailed description of the final design. The proposed design addressed age-related impairments of elderly drivers through a combination of blind spot sensors and a smart camera. The team borrowed several early-development concepts, as they did not have the...
Joint Stress Analysis

Joint Stress Analysis

Joint Stress Analysis Performing a structural analysis on a dovetail joint to determine both the locations of maximum stress and magnitude of the maximum tensile load. While completing a solid mechanics course, Nathan and a group of colleagues were tasked with analyzing the stress patterns over a dovetail joint as it was subjected to several increasing nominal loads. This dovetail joint was to be within a compressor of a turbine engine. Based on the material properties of the dovetail, as well as the stress and strain levels measured under each successive loading, they were able to calculate where and when the joint would fail. The dovetail joint was first fitted with strain gauges to record physical results based on the responses received under the set loadings. This data was then compared to the results obtained from using ANSYS Engineering Simulation Software. Next, material properties of the dovetail, such as the Poisson’s ratio and elastic modulus were recorded. Using ANSYS, Nathan performed a finite element analysis of the dovetail configuration. The image to the left shows a plotted von Mises stress contour, representing the levels of stress at various locations on the joint when subjected to a 1 kN nominal load.  The team also conducted a photo-elastic stress analysis, resulting in the isochromatic stress diagram and plot shown to the right. This allowed for further calculation of the maximum principal stress based on the highest fringe value, which was then compared to the maximum principal stress value calculated in the finite element analysis. Nathan and his team used the strain gauges to confirm the results obtained from the finite element and photoelasticity analysis. This determined the...