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:
“The inability to control our childrens behavior feels the same as not being able to control it in ourselves. And the fact is that primitive behavior in children does unleash primitive behavior in mothers. Thats what frightens mothers most. For young children, even when out of control, do not have the power to destroy their mothers, but mothers who are out of control feel that they may destroy their children.”
—Elaine Heffner (20th century)
“The poets were not alone in sanctioning myths, for long before the poets the states and the lawmakers had sanctioned them as a useful expedient.... They needed to control the people by superstitious fears, and these cannot be aroused without myths and marvels.”
—Strabo (c. 58 B.C.c. 24 A.D., Greek geographer. Geographia, bk. 1, sct. 2, subsct. 8.
“For the mother who has opted to stay home, the question remains: Having perfected her role as a caretaker, can she abdicate control to less practiced individuals? Having put all her identity eggs in one basket, can she hand over the basket freely? Having put aside her own ambitions, can she resist imposing them on her children? And having set one example, can she teach another?”
—Melinda M. Marshall (20th century)