A robot’s life is hard, full of compromise. A robot that desires “independent living” and the unfettered ability to talk, sing, buzz and beep needs an always available audio system. Of course the humans are not going to be agreeable to hearing a shouting robot in the middle of the night, but a smart robot can be selective about when to talk - if the audio system is always on!
An audio system can draw 40-50 mA of power, and power is a prized commodity for a robot. Talk may be cheap, but power - a robot needs to manage the “juice” wisely. For my robot, Carl, 45ma of opportunity to “talk whenever” means the loss of one hour of play time (6+ hours instead of 7+ hours). Carl must spend 2-3 hours on the charger after every play time.
Previously, Carl had a rechargeable speaker that required a human remember to turn it on, turn it off, connect and disconnect a separate charging cable, but the speaker did not draw any power from the batteries. Now Carl has a USB powered speaker that is always on, but draws power from the batteries.)
A robot doesn’t need to talk very often, but it does need to be able to talk whenever it wants.
ps. Carl’s Python speak module has three levels of talking, whisper(), say(), and shout(). He is allowed to whisper anytime he wants, but say() and shout() check quietTime() before blurting out his wild thoughts.