Control
Robotic spacecraft use telemetry to radio back to Earth acquired data and vehicle status information. Although generally referred to as "remotely-controlled" or "telerobotic", the earliest orbital spacecraft – such as Sputnik 1 and Explorer 1 – did not receive control signals from Earth. Soon after these first spacecraft, command systems were developed to allow remote control from the ground. Increased autonomy is important for distant probes where the light travel time prevents rapid decision and control from Earth. Newer probes such as Cassini–Huygens and the Mars Exploration Rovers are highly autonomous and use on-board computers to operate independently for extended periods of time.
Read more about this topic: Robotic Spacecraft
Famous quotes containing the word control:
“America is neither free nor brave, but a land of tight, iron- clanking little wills, everybody trying to put it over everybody else, and a land of men absolutely devoid of the real courage of trust, trust in life’s sacred spontaneity. They can’t trust life until they can control it.”
—D.H. (David Herbert)
“If someone does something we disapprove of, we regard him as bad if we believe we can deter him from persisting in his conduct, but we regard him as mad if we believe we cannot. In either case, the crucial issue is our control of the other: the more we lose control over him, and the more he assumes control over himself, the more, in case of conflict, we are likely to consider him mad rather than just bad.”
—Thomas Szasz (b. 1920)
“I have not ceased being fearful, but I have ceased to let fear control me. I have accepted fear as a part of life, specifically the fear of change, the fear of the unknown, and I have gone ahead despite the pounding in the heart that says: turn back, turn back, you’ll die if you venture too far.”
—Erica Jong, U.S. author. In an essay in The Writer on Her Work, ch. 13 (1980)