A few days ago, the Mars-rover Curiosity suffered from a glitch, as a result of which the robot was unable to orient itself and could no longer move. It has since become clear that the rover has been ‘patched up’ again and is ready to carry out the planned scientific studies.
NASA scientist Scott Guzewich writes that a plan to give Curiosity enough knowledge about its orientation has been successful. He states that the rover has in the meantime again received a comprehensive plan with investigations, which should have been carried out earlier, prior to the occurrence of the problems. For example, the rover must do research with his Alpha Particle X-Ray Spectrometer to determine the chemical composition of samples. According to the plan, this spectrometer must also be used for a rare measurement of the amount of argon in the atmosphere.
It is unclear what exactly caused the problems. In any case, it is certain that some of the data about the orientation of the rover was not entirely correct, which meant that the robot was unable to perform the essential safety assessments that are crucial for its functioning. Thus the robber stopped moving, although he continued to send information to the earth. On that basis, NASA came up with a plan to inform Curiosity about its environment and orientation.
Robbers like Curiosity, just like people, have to be aware of where their ‘bodies’ are exactly in relation to the environment. Curiosity stores this data in its memory, including the orientation and angle of each ‘joint’, which instrument at the end of the robot arm points downwards and how close an instrument, such as the said spectrometer, is to the ground. Curiosity also stores data such as how steep a slope is and where there are large boulders. All that information is evaluated before an engine is activated. If the rover judges that a movement cannot be performed safely, the relevant motor is not activated. According to NASA, this conservative attitude helps keep the robot safe and operational. In this way Curiosity is prevented from hitting a boulder with his arm, driving over something dangerous, or pointing an unprotected camera towards the sun.
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