'discipline' in this context means "field of study" as Simon mentioned. The term "discipline" is often used in academic studies or higher education. Eg. "Mathematics is one of the disciplines (fields of study) you can take at my local university".

One will have to read more of the story but what I can understand is that since the robots are autonomous it will work hard and follow humand comands. When a human is disipline it means that person does what he had plan to do no matter if circumstances change. For exaple for a person that goes to gym everyday, one can say he or she is very disciplined. Could also be refering to the disciple of a marine archaeologist. The study of... depending of what the article is referring to. It's in the context.

You could substitute "profession" for discipline here but that is not quite what it means. Discipline in this context means a subject of training or study.