It’s Science Week at school and the boys were given an optional science project to work on: make a ping pong launcher. Seizing the opportunity for a bit of father-son bonding, I handed the task over to Dad to guide the boys through their design process and construction of the launcher.
Create a Ping Pong Launcher
https://www.youtube.com/watch?v=LtP7SNutT7M&feature=youtu.be
The Task: Design and build a device to launch a ping pong ball as far as possible with the following considerations:
- The device must be free standing, although you are allowed to stabilise it.
- There must be an elastic component to the device.
- The distance travelled by the ball will be measured up to the point of first bounce.
Things to think about:
- What research could I do before I begin?
- How will I test my ideas?
- Can I record my results?
- What changes could I make?
Ideas to get started with:
The Scientific Process
The goal was to encourage the children to drive the design and construction of the launcher with parents functioning as guides only. In other words, parents, don’t make it for them! The suggestion was to follow the four-step process of:
- Plan
- Do
- Review
- Amend
The Work in Progress
G1 came up with the following basic ideas:
- Trebuchet – like the one he made for Art class
- Slingshot – like the one from Angry Birds
- Gun
We trawled the Internet to “borrow” some working ideas.
Prototypes and Rough Ideas
We tried to keep it simple and minimise – no pins or glue, just elastic connectors. G1 and Dad came up with a couple of prototypes for the gun/slingshot which could have worked if they had refined the ideas further.
There was some discussion about ballistics involving launch angles and ping pong trajectory. They were trying to figure out optimal launch angles to extend the horizontal distance covered by the ping pong ball before its first bounce.
One of the requirements for the competition was that the ping pong launcher had to be able to stand on its own. That meant that if we made the slingshot or the gun, we would have to mount it on a stand-alone frame. At this point G1 decided it would be less work to use the trebuchet idea since trebuchets by default have a stand alone frame.
The Final Ping Pong Launcher
This was the final device that eventually went to school (yes, it looks uncannily similar to the trebuchet for his art project). Ah well, if an idea works well, why not use it again.
Extensions
This has nothing to do with the Science Week competition but if you want to take the Ping Pong Launcher to the next level and explore the physics in greater detail, check out the videos on Khan Academy.
Kevin James says
Lee I can’t thank you enough. I shamelessly copied the design for my sons class project. And guess what he got third in the competition. My young one is so happy, thanks to you.
More power to you.
Shen-Li Lee says
Thanks Kevin! I’m glad it worked out for your son’s project!