I was recently watching two wasps communicate with vibrations. These are inch sized black wasps that inspect holes. One of the wasps was half way inside a hole while the other wasp was flying at 5 inches behind looking directly at the first one. The flying wasp emitted quick buzzing sounds that I could hear across the garage. It seemed to use a kind of Morse code.

This made me curious about what mechanism the wasps could use to generate these sounds. Since I'm building a wearable computer, I'm looking for skin/bone communication methods. Wondering whether high freq vibrations could be used for this, and how low power and miniaturized it can be.