The Talking Drums of 2016

Using Sound as a Semaphore System

Posted by Patrick Sheldon Wee on October 9, 2016

Semaphores! When I first heard about semaphores, the first thing that came to mind were mushrooms of some sort. Maybe, it reminded me of spores! But for Communication and Technology, we were supposed to build a semaphore, or "a system of sending messages by holding the arms or two flags or poles in certain positions according to an alphabetic code." We wanted to think out of the box though, and use sound as a semaphore system. Hence, we devised the "Talking Drums of 2016!"


We had a couple of ideas in mind when we started with this competition. In particular, we had two ideas, using sound or using visuals."

While we considered simply drawing out letters on a piece of paper, and then showing it to my partner in this competition, Mark, we thought that using sound is probably going to be cooler, and something more novel, and so we went ahead and decided to use sound as our semaphore!


In order to build out the protocols, we needed to decide which sounds symbolized what. To do that, we initially thought of using binary, 0's and 1's of base 2 that then give us a number, that then we can map onto the alphabet. We realized that this took time, so we needed another system.

We decided that we could use each drum beat to symbolize a denomination, much like money. Hence, a beat of the bass drum could mean 5, another drum, 1, which would make transmission way faster. We also initially thought that we would symbolize numbers differently by adding another drum to alert the receiver that a number was about to come up.

We optimized this even further by just using the numbers 1-26 to symbolize the letters, and 27-37 to symbolize the numbers 0-9.


With this design in mind, we decided to start selecting drums for the job. At the end, we used three drums, the bass, the hi-hat and the snare drum. We used the bass as the signaler, it was used to space out different letters. It was also used to start and end messages. We then used the hi-hat to symbolize 5's and used the snare drum to symbolize 1's.

So, for example, to transmit the word, "HELLO", you would need to first translate it into numbers, "8,5,12,12,15", and transmit it through the drum as "hi-hat snare snare snare BASS hi-hat BASS hi-hat hi-hat hi-hat snare snare BASS hi-hat hi-hat hi-hat snare snare BASS hi-hat hi-hat hi-hat."


During our practice, we started to realize that it actually might take a while to move our message. (Or at least not as fast as just a visual system!) It was a fun try though, because it allowed us to explore new ways of using familiar types of communication.

On competition day, we realized that we actually took longer than we anticipated. Our message was something to the lines of "Bridge flooded. Avoid north for 2 days," but we were only able to come up with barely the first word.

While we weren't successful with our endeavor, it was a good try though, because it allowed us to really see the pros and cons of our desired technology, and make us think about it in a whole new way. It allowed us to innovate, and explore. And hey, this is like when Edison tried to invent a light bulb and failed, and realized that that failed trial was just one way not to build a light bulb!

Next Steps

We realized that some of the next steps we can do is to not include the vowels in the system, and to maybe have a phrase book with the most common words in the english dictionary so we can just drum those instead of individual letters.

Overall, it was a great experience. I really learned a lot, and I enjoyed the process as documented above. Yay! I'm ready to see the Third Annual Semapore Competition!