THE POGO PROJECT
The Pogo Project bridges the gap between children’s pogo sticks and the expensive & extreme adult pogos currently on the market. TPP employs a carbon fiber spring that bends like an archers bow to provide a fun and safe experience that is missing from the traditional pogo stick. Riders of this pogo will experience a new level of comfort, jump ability, and overall exercise value.
Contact kpelton@stanford.edu to view the full PDF report.
Final Design
By replacing the steel compression spring used in conventional pogos with our high-performance carbon fiber composite, TPP provides more effective energy storage and return. In addition to its ability to absorb more force, the carbon fiber composite bypasses sliding friction and lateral buckling of traditional sticks to provide a superior jump experience.
Carbon Fiber Extended
Carbon Fiber With Deflection for Bounce
Design Decisions
After picking the pogo stick as our product to re-imagine, we first examined current models on the market. We decided that the three re-design directions we could take were to focus on comfort of the user, extra features, or performance of the pogo. We used PUGH and MAUT matrices to help make our decision to focus on improving the performance of the pogo stick. As a group we did a series of mind mapping and 6-3-5 concept generation activities to help each of us think outside of the box to re-imagine the pogo stick. ​​
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As shown in our concept generation, we looked at several different performance ideas such as collapsible handle bars, a multi-surface landing tip, redesigned foot petals, and a new spring mechanism. Ultimately, we decided to continue with the re-designing the spring mechanism because it seemed the most exciting and innovative of the performance ideas. Our original ideas for the spring mechanism was a type of carbon fiber spring similar to the prosthetic legs disabled runners use and a rubber band powered pogo. Through team voting, along with more PUGH and MAUT matrices, we decided to attempt to power our pogo with a carbon fiber spring. We wanted a max potential jump height of 2 meters and we were interested in looking into the spring shock absorption to increase comfort while jumping. Our original ideas for the carbon fiber spring included a prosthetic jumping spring and a sliding spring.
Sliding Spring
Prosthetic Jumping Spring
Functional Protoype
To test our carbon fiber spring, we created a simple functional, testable prototype of the carbon fiber leaf spring. By epoxying thin strips of carbon fiber together, we were able to create a prototype we could test. We hand cut the carbon fiber to precise dimensions, glued them together, let them try, drilled holes into the carbon fiber, then attached it to a steel clamp for testing.
With the help of the Mechanical Engineering Professor, Scott Crawford, we inserted our carbon fiber spring we constructed into the MTS testing machine. The MTS machine applied a force to our spring and measured the deflection of the carbon fiber as a result. This testing proved extremely important, as it allowed us to create more exact dimensions of our spring such that it would be able to reach our desired max jump height of 2 meters.
Modeled in SolidWorks
MTS Testing
Models
Engineering Model
To understand how our pogo stick in greater detail, we created a series of models in Excel. First, we constructed an engineering model to see how the pogo stick leaf spring would function. Consulting with several Mechanical Engineering Professors at Stanford, we were able to model our sliding carbon fiber spring as a leaf spring. We used the deflection of the dimensioned carbon to determine the potential energy it would provide to our pogo user. Then, using the function Solver, we created an optimal ratio of user weight and jump height to get our desired max potential jump height of 2 meters. Later, when we constructed our functional prototype, we used the data from the MTS testing we preformed to update our model with the width and thickness of our prototype.
Manufacturing Model
After creating our engineering model and functional prototype, we were able to form the idea of how our pogo should be constructed. In our manufacturing model, we listed out all the parts of our pogo, and determined the cost of the components was $96.59. When including sales rep commissions, warrantee take backs (1 in 500), shipping from Asia, distribution, and warehousing, the cost of our product increased to $101.28. However, we also had to include the price of salaries of our employees, 3rd party online vendors, legal patents, advertising, cost of injection models for our handlebars, and research and development, our price increased to $115.54. This cost includes the above costs distributed over the number of projected units sold per year (this number is based on our marketing model). Ultimately, to make a profit, we sold our pogo stick for $131.54.
Marketing Model
Our market model was constructed based on the market for pogo sticks in the United States and how desirable our pogo stick is based on the feedback from our user survey. We determined that the pogo market was roughly 270,000 pogos sold per year in the US. We were able to use the CBC survey data to analyze how our pogo stick would fair on the market. Through Excel, we were able to calculate the utility of our product. To make our model more realistic, we also calculated the utility of an existing pogo on the market. Without a competitor, our pogo is projected to capture 22% of the market, and with the competitor in the model, 13%. When connected with our profit model, this market share equates to about $ 5,359,560 in the first 5 years.
Linked Models Summary Table
User Survey/Feedback
To effectively create a marketing model, we needed to understand what consumers wanted in a pogo stick. We constructed our user survey to understand the background (age, weight, experience with pogo sticks) of our users and what attributes they calued most in a pogo stick. Through the use of both CBC (choice based conjoint) and non-CBC questions were were able to better understand how our pogo stick would fair on the existing market for pogos. The CBC questions were particularly helpful as they were able to help us determine the most important aspects of a pogo. In our survey, we found that they cost of the product was most important, and the least important as the lifetime/durability of the product. Other important attributes included jump height and impact on the body. As the pogo market in the United States is not very large, we were not incredibly surprised with the results we received from CBC data results. Because of this small market, it makes sense that the price is the most important as most of the public are not actively looking to buy a pogo stick to begin with.
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CBC Takeaways
Viability
We expect to make a modest profit over the first five years. Targeted advertising, social media marketing, and word of mouth will help expose our product to more people and increase our market share. As we grow, we will continue to invest money into R&D to continue to innovate and improve our product.
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Moving Forward
Going forward, we plan to explore how we can improve design features beyond the carbon fiber spring and ultimately construct a final functional product.
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