.
Executive Summary
The Bicentennial Wheel serves as both a decorative and functional product, storing coins in baskets before depositing them into a drawer at its base. Inspired by the Ferris wheel (invented by an RPI alumnus), the project integrates diverse manufacturing techniques such as CNC milling, injection molding, laser cutting, waterjet cutting, and ultrasonic welding. Its structure features metal uprights and slats with riveted connections, while the mechanical motion is driven by a crank mechanism and plastic baskets to deliver coins to the base.
Product Engineering and Design
The engineering process began with brainstorming, benchmarking, and iterative refinement. Key design decisions prioritized durability, simplicity, and scalability for mass production. Subsystems include the coin slide, base and uprights, wheel plates, and baskets. The coin slide facilitates the coin’s journey into baskets, which rotate and release coins at a designated position into the drawer. Materials like aluminum, acrylic, and ABS plastic were selected for strength, cost-effectiveness, and ease of processing.
Manufacturing Methods
Detailed manufacturing methods were proposed for each component:
Metal parts (uprights, slats) are waterjet cut and bent into shape.
Plastic parts (baskets, coin slide) are injection molded for precision and efficiency.
Acrylic components (wheel plates) are laser cut and engraved for aesthetics.
Assembly processes include riveting, heat staking, and ultrasonic welding for robust connections. Robotic tools and manual methods are balanced to ensure speed and accuracy during assembly.
Assembly and Packaging
The assembly plan divides the process into subsystems, enabling efficient production. Fixtures and jigs simplify alignment and minimize errors during construction. Packaging is modeled after toy products, with custom laser-cut poster boards and labeled cardboard boxes, acknowledging sponsors and providing visual appeal.
Budget and Cost Analysis
The budget covers raw materials, manufacturing, tooling, and assembly costs, totaling $2,672.20 within the course constraints. A separate real-world budget estimate of $236,860.07 accounts for professional-level production, including labor and advanced machining.
Challenges and Solutions
The document outlines several manufacturing and assembly challenges, including achieving tight tolerances, minimizing assembly errors, and optimizing the tipping mechanism for coin release. Solutions involved prototyping, testing fit tolerances, and refining the design based on performance data.
Prototyping and Testing
Prototypes were built at each stage to validate the design. Tests confirmed the structural integrity, fit of moving parts, and smooth operation of the coin-handling mechanisms. Adjustments were made to improve alignment, reduce friction, and optimize coin flow.
Conclusion
The Bicentennial Wheel exemplifies a multidisciplinary approach to product development, combining mechanical design, material selection, and advanced manufacturing techniques. It highlights the team’s ability to manage costs, meet production goals, and deliver a functional and commemorative product, preparing them for real-world engineering challenges.
The Bicentennial Wheel
Take a minute to write an introduction that is short, sweet, and to the point. If you sell something, use this space to describe it in detail and tell us why we should make a purchase. Tap into your creativity. You’ve got this.
The video above is of our first functional prototype: