Mechanical Design

Design of a slow cooker using design for manufacturability and assembly (DFMA) principles (Team)

  • Redesigned an already market available slow cooker based on user centered design process.

  • Generated BOM, QFD, and conducted market research, customer interviews, cost-worth analysis, DFM, DFA, and target costing.

  • Proposed design changes that could potentially increase sales by 250k units per year, and design efficiency by 3%.

The project involved choosing an existing market available product and try to find ways to redesign the product. Thorough market research involving analysis of competitive products, potential target market, market size and net revenue analysis was carried out.

Using the principles of DFM and DFA, design changes were proposed that could increase the market share and increase revenue for the product. Bill of materials (BOM) and quality function deployment (QFD) approach was incorporated to study the cost-worth of each individual component of the cooker. 3D CAD models of the propsed design changes were prepared and presented along with target costing, including all manufacturing, tooling, labor, distribution, and retail costs.

By incorporating the given changes, the product could compete in a higher tier market of the product, thus, increasing the sales by about 250k units per year. The said design changes also resulted in a 3% increase in design efficieny.

Product Design: Dr. Sous, Kitchen Countertop Extension (Team)

  • Designed a product by identifying a pressing customer need, conducting customer interviews and market research.

  • Manufactured product using industrial grade materials under design and cost constraints (max. 50$ retail price).

  • Presented product at a design fair to various students and faculty; estimated profits on sales were $106k.

The project dealt with designing a product catered around immediate needs of college students. A cost contraints of $50 retail price was placed on the product.

The core need of the availability of additional kitchen counter space was addressed. Final bill of materials (BOM) and design of the product was based on customer interviews, customer needs, and competition analysis. 3D CAD model of product was created. The design was reformed over successive iterations that were then presented and critiqued upon by students and faculty. Final target cost and retail price for product was decided depending on manufacturing costs and estimated profits.

Final prototype was presented at the Penn Design Fair 2017 which was judged by potential customers. Estimated profits based on results were about $106,000.

Design of an Axial Compressor for Use in the SpaceX Hyperloop System (Team)

  • Designed 20:1 compression ratio axial compressor for given Hyperloop operating conditions.

  • Studied velocity triangles for rotors and stators to model each compression stage.

  • Generated 3D CAD assembly for compressor.

The compressor is an integral part of the Hyperloop system, enabling the whole pod to reach its maximum attainable speed and provide enough power for the same. Over the course of this project, we have designed an axial compressor with a pressure ratio of 20:1 to achieve this purpose.

The design in based on the inlet and exit conditions mentioned in the SpaceX Hyperloop Alpha paper. The effective length, inlet and exit velocity of the air, the desired compressions required along with the manufacturing specifications have been incorporated to reach the final design for the axial compressor.

Velocity triangles at each compression stage are studied for the rotors and the stators. Based on these calculations, the optimum blade angle has been devised for each compression stage. The geometric modeling of the complete compressor is carried out using Solidworks.

Simulation and Analysis of Human Skeleton Joint (Team)

  • Simulated normal walking cycle and identified joint reaction forces at the hip, knee and ankle joints using OpenSIM.

  • Studied ankle-foot orthosis to develop basic design for foot orthotic to prevent ankle injury.

  • Explored reduction in metabolic costs in normal gait cycle.

Biological systems are much more complex than man-made systems. Hence, research in biomechanics is done in an iterative process of hypothesis and verification, including several steps of modeling, computer simulation and experimental measurements. This design project explores the power and relevance of numerical methods employed by state-of-the-art modeling and simulation tools (OpenSim in this case) in the context of research in biomechanics of the human musculoskeletal system.

It is divided into 3 independent sections – joint reaction estimation, simulation based design to reduce metabolic cost, and simulation based design to prevent ankle injury – each with a different type of computational analysis. The applications and merits of these methods are looked into in addition to acknowledging their limitations and simplifying assumptions. We realize that, given reliable experimental data, accurate and insightful results can be arrived at and hypotheses validated, using such methods. They also circumvent many of the cumbersome, expensive and often invasive experimental methods required to achieve the same results.

Apart from validating hypotheses, these results can be exploited to a great effect in the rapid, iterative evaluation and optimization of designs of assistive devices and training programs for rehabilitation, or enhancement of athletic performance.