I want to turn a robot's head towards the direction of the speaker talking to the echo. How do I derive this information from the echo?
Sorry, this functionality is not currently supported by the Echo. To do this, you would need access to the energy levels from each microphone in the mic array (disc), or perhaps intercept the LED interactions. This would require some device level programming. A simpler (although still non-trivial) approach might be to just do some visual detection of the LED ring on the echo, as the brightest part of the edge identifies the direction of the incoming voice.