There are also currently no mainstream self driving cars. I believe the context is brainstorming ideas for things obtainable in the (near) future, not limiting

There are also currently no mainstream self driving cars. I believe the context is brainstorming ideas for things obtainable in the (near) future, not limiting ourselves to current tech. Although I feel a $50 motion sensor from the JC Penney dressing room may cover (or come close) to what you mentioned. We’ve been to the moon! Let’s not be so bleak.