I have heard the terms tether and umbilical used interchangeably, and I wondered if there was any difference. In my mind a tether is for communication, and an umbilical supplies power as well as information. Is this right?
I worked with a professional ROV manufactuer in the late 1970’s in El Cajon, Ca (Ametek, Straza). Our vehicles used an umbilical, yellow rubber covered umbilical, with many wires for video, multiplexed communication, and power. We considered the umbilical was used to teather the vehicle. I wrote the technical manuals for Scorpi and Scorpio models. I am building a 2.8.