As fun as it may be, many people are aware of the risks and dangers associated with trampolines. Falling off, landing on the springs, landing on somebody else; these are all possible dangers many kids face when bouncing around with friends. Now, we have nets to keep kids from flying off and mats to cover those springs. However, even with the safety equipment on and installed properly injuries can still occur.
Therefore, there must be some way in which kids can still have fun on trampolines, but in a much safer manner. That is the work Dr. Keith Alexander has been working toward. As an associate professor of engineering from Canterbury University in New Zealand, Alexander wanted to create a safer trampoline for his daughter. He began his work by making prototypes in his free time at his home. As time passed he then decided to get the university involved within the project.
With the help of his students, lots of research was conducted to come to the conclusion that there are three critical areas of safety concern. These include, the springs of the trampoline, the metal frame, and the ground all around the trampoline. These three areas have been associated with the largest percentage of trampoline related injuries. As a result, Alexander came up with a new design that will address these three areas of concern and overall, create a newly designed trampoline.
To take care of the springs and metal frame area, the design has been changed from horizontal springs attached to the mat to vertically slanted bars. Each of these bars, usually at least 60 or more depending upon the size of the trampoline, are created from fiberglass. Due to the properties of fiberglass, each of these support rods are extremely durable, lightweight, and robust. Each of these support rods then connects to the bottom of the top mat and then to the top of the metal frame at the bottom.
Using a ball and socket type of approach, each rod fits into theses T-shaped cleats and supports the forces of the mat moving up and down. In fact, these cleats were such a complicated piece of the design that they had to get help from a consulting group, Matrix Applied Computing, for the most optimal product.
As a result, Matrix was able to apply their experience with Abaqus finite element analysis (FEA) from SIMULIA to the project. Using the models and simulations, they were able to create a stronger cleat that would increase the overall load capabilities of the trampoline. The final cleat design they came up with uses a little less material and has two ribs for added support in the areas of high stress.