PFS issue on Venus Express, PFS scanner stuck in its closed position Options

[Rakhir]

Bad news for PFS. I hope they will be able to solve this issue.

The PFS scanner is stuck in its closed position.
Several attempts to move it were made at the time, but the instrument did not respond. Experts suspected a thermal problem by which low temperatures were blocking the rotation of the mechanism.
Another attempt to move the scanner was made on 16 March 2006, in warmer flight conditions. Unfortunately, the scanner remains stuck.

The next opportunity to perform another test on the spacecraft will be end of April, after the Venus Orbit Insertion.

From http://sci.esa.int/science-e/www/object/in...fobjectid=38964

[RNeuhaus]

Thanks much Rakhir for the pointing topic.

I was thinking that any probe, robot, rover or any spacecraft must carry along with him an useful and smart general purpose arm to solve for any problems that they might be stuckduring its exploration.

The robot arm plays the rol as an auxiliar for any mechanical problems such as to align correctly the motor troubled antenna; puff off the dirt from lens, unstuck the troubled panel solar; repair a panel solar; lift off from the surface the troubled wheel (the wheel must be designed to be able to lift off independently from the other, this is the MER's problem and MSL might have it); help to unstuck /stuck the IDD; push any interesing rock to see its bottom; help to tilt the rover to a right angle in anywhere when the battery is low; and many much useful auxiliar examples that a arm can help to rovers.

The good example was the ones from Shuttle. Its long arm has helped to simplify and solve the thermal problems by removing a small debris under the nose.... Why not any spacecraft bring an arm with itself! Spirit need a help from a smart arm to spin the injured wheel or knock softly it to see if the motor will turn on again

Of course, that carrying an extra weight of the arm, it would save millions dollars if the problem is arised. It is like a kind of space insurance. Now, the troubled PFS is the point of iceberg for this discussion.

Rodolfo

[djellison]

Of course, that carrying an extra weight of the arm, it would save millions dollars if the problem is arised. It is like a kind of space insurance

Unfortunately on the size, volume, mass, power, money, development budgets of anything short of a space shuttle, it just doesnt make a lot of sense, and is basically impossible.

For example - you'd have to ask "OK - do I want 6 instruments on VEX, or 2, plus an arm to make sure they deploy" or "an extra 50kg of hyrdazine for a great extended mission for 5 instruments, or a system that might or might not guarentee 6 instruments for 5 years less time"

Doug

[RNeuhaus]

Unfortunately on the size, volume, mass, power, money, development budgets of anything short of a space shuttle, it just doesnt make a lot of sense, and is basically impossible.

Interesting view. The weight of sense is the factor to decide if it worth or not to take an multi-purpose arm as an kind of space insurance (orbiters and rovers) and also for science purposes which would be most useful for rovers. The money is a balance decision factor for many things according to our monetary society. It is the product of our still young technology of propulsion system.

Rodolfo