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

[djellison]

Boys - don't make me come in here!! Inappropriate politics removed.

I'm amazed you've not had a dig at something/someone about this one though Bruce - deployment of devices in space is something you've enjoyed lambasting in the past ( based on Galileo and MEX )

Doug

[The Messenger]

Boys - don't make me come in here!! Inappropriate politics removed.

I'm amazed you've not had a dig at something/someone about this one though Bruce - deployment of devices in space is something you've enjoyed lambasting in the past ( based on Galileo and MEX )

Doug

It is not inappropriate to complain about the untimeliness of this release. In a worse case scenario, the failure will be traced to widget xyz, and the same widget has a deployment function on New Horizions.

Failures of space-based hardware need to be known and understood by the space design communtity in a timely manner, so we can look under the bonnet of anything we are building and fix it, before it hits the street. This is a space health management issue...

[djellison]

It is not inappropriate to complain about the untimeliness of this release...

It IS inappropriate to bring Iraq into it, to use a rather crude phrasology when refering to the Italians and to have a post that saying nothing but "Grrrrrrrrr"

Doug

[Guest_BruceMoomaw_*]

It IS inappropriate to bring Iraq into it, to use a rather crude phrasology when refering to the Italians and to have a post that saying nothing but "Grrrrrrrrr"

Doug

Yeah, actually it was (although you'll note that I was actually sneering at US pretensions of superiority in that post, by doing a Merle Haggard imitation with a sarcastic snark at the end). My apologies. (Also, I thought Messenger was GRRRing at me, rather than at the damn PFS.)

I would imagine that solar cycling has as much chance of remedying this as anything, although it will be tricky to pull off.


If they can't correct this, it WILL be a pity to lose it -- PFS was the second most important instrument onboard. Yet again, moving parts prove to be the bane of space missions, and we have proof that it's better to err on the side of excess in designing the strength of actuators (whether motors or springs).

[djellison]

.... Yet again....

BINGO - Alex now owes me $1 - we had a book going on how long it'd be

He had 'increasingly obvious' for $2, and I had 'JAXA' for $3.

Good job you didnt mention the Discovery program, that would have emptied my wallet.

Doug

[The Messenger]

BINGO - Alex now owes me $1 - we had a book going on how long it'd be

He had 'increasingly obvious' for $2, and I had 'JAXA' for $3.

Good job you didnt mention the Discovery program, that would have emptied my wallet.

Doug

You blokes will take a wager on anything! I Guess Bruce's predictability is a safe bet

Most of the tasking in the building I work in is related to flight hardware predicability: We stress, we strain, we Eddy, ultrasound, Xray, thermal image for ply debonds and on and on. We do it in vacuum, at extreme temperatures. A chemist down-the-hall from me has even tested deployment in the 'vomit comet'. We do everything we can think of that will assure the hardware will perform the way we expect it to, where we expect it to.

What I am getting at, is I am sure they are doing these same things in Europe, and expecting the designs to work under any and all possible conditions. So why so many failures? We must not understand all the failure modes. I can't pull up the level of detail I think would be necessary for me to understand the deployment difficulties experienced by the Mars Express, and I cannot even begin to comment on whether or not the PFS problem is in any way related. But I get to wonder out-loud if the Venus Express engineers are completely on-top of the possible failure modes of the Mars probe, and if they addressed the issues.

We have a prospective of how tightly the different Huygens groups guard their data, not always sharing with each other. Did the Venus Express engineers have a detailed report on the Mar Express boom problem, and upon why Huygens channel A failed?