Mars Exploration Rovers Update
7 Nov 2002
(Source: Cornell University)
http://athena.cornell.edu/news/index.html
Week Ending November 1, 2002
Well, we're hunting our problems down and killing them off one by one. But some are easier to deal with than others. Last week we found and fixed the Mini-TES step-and-settle bug. This week, the focus has been on fixing the Moessbauer Spectrometer problem that turned up a couple of weeks ago. Hunting down a problem like this can be tedious, and you have to be very methodical about it. You might start off with half a dozen different theories about what it could be. Then you have to come up with a test for each theory, and run through all the tests... knocking theories off one by one until you find the culprit. In this case, the culprit seems to be some rather innocent-looking wires. They're the wires that run up the rover's arm, connecting the Moessbauer's sensor head (which is out on the end of the arm) to the part of the instrument that's inside the rover. This thing isn't a normal bundle of wires, though. A normal wire bundle would be too stiff for the arm to bend. Instead, it's a very special kind of flexible cable. If the flexible cable is in place, the arm bends just fine, but the instrument doesn't work right. Replace the flexible cable with a normal bundle of wires and the instrument works fine. But we can't fly it that way, because if we did the arm wouldn't bend! So we have to figure out what's wrong with this flexible cable, and fix it. At least we know where the problem is now.