"In the loop" has a few different meanings. The most common person means someone who is involved in or has knowledge of a particular event occurrence. For example, if your boss says "Please keep me in the loop on this project", it means that he wants you to keep him informed and up-to-date about what is happening. The opposite phrase, "out of the loop", means someone who is uninformed about something, or doesn't know anything about a particular matter. For example, if someone says "I am completely out of the loop on this", it means that they don't know anything about the current subject of conversation. However, in *this* particular case, it sounds like the person speaking is an engineer talking about a self-driving car. From an engineering perspective, he is probably talking about the "control loop" of the car - the driver sees what's happening, they make inputs to the car's controls, the car changes direction, the driver sees what's happening, the make inputs to the car's controls... etc. In this case, the driver has been removed completely from that loop and been replaced by a computer. Hope that helps.

People use 'in the loop' to mean being aware of something. For example, if I were hosting a party and I changed the time it started I would tell other people to keep them 'in the loop.' Not knowing something means you are 'out of the loop.'