The biggest obstacle to repair of the rovers is the timing. The time that has past, four years of work on Mars, is a vast length of time for rechargeable batteries to last. The time left in the batteries is short, as they are recharging at a lesser total capacity, and declining as time passes.
We are watching the rovers 'get old', and they have done so gracefully, finding samples and new photos to send back all along the way. It has been a great time for us in receiving more information about a planets surface than has been accomplished in any past landing, on all prior missions.
The suggestion of a landing with a rover, to replace battery packs is a great idea, and it could be a very smart way to explore a planets geology. The rovers could resupply each other with additional batteries while still in good operating condition, or, even replace a robotic arm. possibly.
The process of replacing a robotic arm is very difficult, however, and currently we can't perform that type of repair. These rovers were assembled with no removable parts once on Mars.
I believe your suggestion of a renewed mission by additional robot rovers is a good one for future missions.
Even a simple battery pack drop-off as a fixed package which a rover could use to renew it's power system is a possibility.
One rover, two power packs, and perhaps more. The process could allow us to travel thousands of miles, without giving up on good rovers in fine working condition.
Currently the rovers are having some slight general upkeep problems, but they are still working to send back much needed information about Mars geology and weather.
Detachable and resealable power system battery packs for future rovers. Arms that can be detached and re-attached by other rovers or by the rover itself. Both might aid in solving future problems of long missions.
Perhaps Cathy's ideas will help in future work, although it isn't possible with the current design of the rovers as they are.
Other good ideas, anyone?
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