Has anyone any idea what kind of imaging system is being proposed for the MSL? Would it be the same or simiilar to the MER's, or as improved as the MER pancams are to those that were used on Pathfinder?
With a nuclear power source for the rover, and hopefully the mars telecoms orbiter in place the data rate and data volume could be phenomenal
Going on the recent news ( i LOVE looking at really old forum posts ) the answer involves any and all of the following words
Order of Magnitude
Can of Whoop Ass
Mike Malin
VIDEOS
Where did all my bandwidth go
Doug
The new bandwith that the MRO will transmit is between 1 to 30 MBits/sec depending upon to the Mars' atmosphere transparency between MRO and Earth. The improved transmission bandwith is based on new technology of utilizing the bandwith closer to the light.
Rodolfo
There was a lot on this at the recent LPSC:
http://www.lpi.usra.edu/meetings/lpsc2005/pdf/1214.pdf
http://www.lpi.usra.edu/meetings/lpsc2005/pdf/1170.pdf
http://www.lpi.usra.edu/meetings/lpsc2005/pdf/1580.pdf
Forgive me for opening up an old post, but I am a little confused on how Mastcam can aquire both multi-spectral, aswell as natural color imaging all in the same package. How would this all work out when there is bayer filter limited to the visible spectrum and IR filters that move into the infrared part of the spectrum?. How could any narrowband information passing through the filter wheel be salvaged when the light also passes through a broadband bayer filter?. I emailed the MSSS guys about this but have not got a response back .
Thanks
http://www.unmannedspaceflight.com/index.php?showtopic=4251&st=20&p=91486&hl=filters&#entry91486
Thanks Doug .
remarkable ChemCam: http://www.youtube.com/watch?v=fEZ5dEi4oPo&feature=related
It's also reassuring that this rover will be able to defend itself if attacked.
One issue that just popped into my head (not sure if it's been mentioned before): MSL will survive for a long time, so there will probably be significant dust buildup on MastCam (and on the other cameras), just like with MER. Phoenix showed that a magnetic ring around a surface will prevent that surface from being covered with dust. Has any effort been put into such a system on MSL's camera lenses? Would it even be possible?
The MER Navcam lenses (esp. Oppy's) have dust accumulations ranging from light to very heavy -- Oppy's are quite occluded on the right sides of the images. However, this isn't a result of general dust accumulation, it happened almost entirely during the global dust storm (which also deposited dust onto the "protected" optics of the mini-TES instruments on both MERs, enough that it might possibly render the devices useless).
I think there's a difference between designing optics to remain "as clean as possible" during normal accumulation cycles and designing dust-storm-proof optics. I'm positive that MSL's cameras are good for the former, but doubt they're designed to handle the latter.
-the other Doug
I wouldn't even know how to begin to implement a "wiper" that would work reliably under martian conditions...
I recall reading that Viking had two methods to avoid dusty optics, a physical barrier which covered the 'slit' when the camera was in its 'rest' position as well as compressed air which could be used to blow off the optics. I would think the latter could be adapted to a wide variety of camera designs.
Don
"I would think the latter could be adapted to a wide variety of camera designs."
I think we need it for Spirit's solar panels now...
Phil
the tank to contain the gas would weigh more than...
Perhaps, but I wonder what the Viking unit weighed? How much more compact cound a similar modern system be built? I imagine something like a soda charger cylinder filled with very clean compressed gas, perhaps giving puff(s) of gas upon demand. A magnetic 'ring' around the lens could also help. However this is dealt with, cameras for long term Mars surface missions will require more attention to the dust hazard as part of the design.
Don
What about holding the air in the bodywork itself?
Making the entire electronics box a pressurised body? Given that it has to travel thru a vaccum? How do you engineer in the insruments and their openings to the sample collection mechanisms. That's an epic engineering challenge right there.
For Mars the body wouldn't have to be at insane levels of pressure - just "enough" over the external ~1 kPa to provide a squirt of gas where and when you need it. I don't think the high pressure 20 MPa sort of structure you see on air tanks is at all necessary here.
Just to put this into perspective: the r/c model sub community regularly work with pressures up to ~50kPa and manage with commercial linkages/prop shafts, etc., penetrating the core electronics box without too many problems.
That said, http://www.amazon.co.uk/Giottos-GTAA-1901-Large-Rocket/dp/B000RGM762/ref=sr_1_4/275-9776193-6764349?ie=UTF8&s=electronics&qid=1226399472&sr=8-4. And it's even rocket-shaped!
Andy
You still have to render the entire box air tight. That means seals of every access panel, seals for every cable in, every cable out. That pressure is going to go up and down with thermal cycles. It might change the thermal properties of the box itself. Then you've got to have valves, flexible pipe work out the box, up the past and to the front of the lenses. Pipework that's going to bend with every camera movement. With all due respect, a $1.X billion dollar rover is just a tiny bit more complex than an R/C sub.
AND - at the end of all that - if you've got a CRT monitor or an old TV - go and blow on it. The dust doesn't move very much, if at all. I know - wind has cleared arrays etc before, but we don't know the mechanism by which that occurs, nor do we know the mechanism by which it sticks.
If we really really want to have dust-removal - the best way is with the thin-film technique I blogged about at Valencia '06. Tiny power, low mass, low complexity. Turn them on for a few seconds - dust gone. Gas tanks, wipers, rolls of film - they're all very heavy, complicated, and have their own failure modes.
DOug
I wonder about maybe some kind of electrostatic "wiper" - maybe something to move across the lens while holding a charge. Might the dust adhere to something like that, or perhaps be repelled by it? Either way, it could get rid of dust. Possibly maybe. I'm afraid I've not got much experience with electrostatics.
There is also the issue of having to make sure that whatever pressurized gas you used didn't cause a residue to build up on the lens. The cure could be worse than the disease.
The thin-film technique is described here:
http://science.nasa.gov/headlines/y2006/19apr_dustbuster.htm
Bingo. That's it. The wires are so fine, I bet for a future design, one could put something like that over the front of a Mastcam like Hood. The wires would be totally out of focus and not noticeable ( like the heating element in a heated front windscreen).
It certainly beats wipers, rollers, blowers etc.
Doug
Just noticed
http://mars.jpl.nasa.gov/msl/spotlight/images/20081119a/20081119_1.gif
It has four rear hazcams - two each side of the RTG. I wonder if it's the same at the front.
Perhaps, but isn't the reason because the RTG would block the view of 1 set of hazcams if mounted in the middle? Or maybe because the rover is just so big; hazards increase with size?
I think it's just that you can't put them where you would want to - because the RTG is there. Can't
What about a stationary brush placed somewhere reachable by the mastcam? The brush could be wiped by the back (or whatever) of the camera housing to brush off dust, and then the brush itself could be used to clean the lenses. We might be on Mars for 10 years (oh joy!), so some sort of cleaning mechanism would seem necessary...
On another subject, I was thinking to myself whether there is some sort of mastcam lens protection during landing. Caps or just turning the lenses towards an enclosed space? A lot of dust will swirl up.
Also, wouldn't it be great if the navcams were turned on during landing, taking a movie? Not just great, but helpful for analysing EDL. If they have caps on them during landing, maybe the caps could be made of transparent material, so some filming would still be possible despite the dust.
Does this MARDI have a microphone, Mike?
Nope, no microphone on the MSL MARDI. You should note that while it shares a name with the instrument on PHX, it's a completely different electronic design and doesn't use the cellphone processor that made adding a microphone to the PHX design fairly straightforward.
You can't simply plug one in through the spare USB port?
Interesting comment about the Mastcams from Mike Ravine of MSSS over at http://nasawatch.com/archives/2009/11/avatar-a-stunni.html#comments
Not entirely accurate is it? If the fixed focus stays - then one eye will be about 3.75x the res of Pancam, the other one, about 1.25x Pancam. But the more I think about it - the more the zoom descope hurts.
Doug, you're right about the resolution. What we are really losing with the zoom is the ability to capture the entire surroundings in color with a small number of frames. As is, we will have only hazcam/navcam monochrome images to do that. And of course there's the 10 fps capability, which is really not that interesting with a narrow FOV.
Damn - 10fps wide angle movies. Driving. DD's. It's enough to bring a grown space fan to tears.
Would it be possible in a future rover to use single shot color imagers for the nav and haz cams? They're not scientific instruments per se, so there wouldn't be much of a penalty.
The "penalty" is technical rather than scientific. Single shot color uses patterned filters on the sensor. The spatial content of the scene is undersampled, and later interpolated. Stereo processing for range maps and navigation would then look at the results of the interpolater. It is not obvious how much degradation there would be, especially if the green channel or maybe the sum of all 3 channels got used in the stereo/navigation processing. But it might be a tough sell without data. (As I recall, using a bayer pattern detector under mastcam's science filters was a tough sell to some of the camera team, and that's a less touchy operation.) For the record, I think it is do-able; but it's not the same to think it can be done reliably versus to show you'll never put the rover in jeopardy due to such a decision.
The balancing operation ugordon describes is something we've been playing with for Mastcam. But note that since Mastcam's Bayer filters are transparent in the near-IR, when we use narrowband filters in those wavelengths the images are effectively grayscale and there is no spatial penalty (we just turn the interpolator off in that case). Of course you wouldn't want to have a filter wheel on your engineering cameras.
If you can get a custom filter pattern applied, you could do RGB_clear_ quads across the chip instead of the RGBG Bayer.
Also, the hazcams on MER were the same die as the navcams and pancams, with the hazcams downsampled. In my idea, use an off-the-shelf single shot color die for navcams and hazcams, with the hazcam SW only looking at one downsampled color channel. The pancam could use the same die without the Bayer pattern, to reduce software complexity and allow full spectral range.
Would there be value to get color info from Navcams or Hazcams? Maybe, maybe not. It might be possible to see a difference in the surface colors that might not be as obvious or distinctive in B&W, ie there's a bluish patch over there, we should check it out vs that's just a typical grey patch, let's move on. The rear hazcams could provide their color data to another process that looks for outliers, ie the white silica that Spirit digs up.
Anyways, sounds like a good PhD project for someone someday.
The kind of ideas here are why I think it can be done. It just remains to be shown that in 99-th percentile cases, it still works well enough to do no harm. Each adds complexity to the data stream--a color camera can generate jpegs without the rover (or camera) cpu being involved. Multiple paths (color download vs. reprocessing the colors to retrieve monochrome) add complexity. Again, something that seems easy to deal with. The software would have to include data from all parts of the pattern through a standard interpolation scheme or through some sort of multiplicative balancing (which is sensitive to small errors in assumed color). Blurring the image could help--aliasing is much worse than oversampling for stereo processing. So, having RGB-Clear and just using the clear would be bad, but using RGBG or RGBC and summing them into a lower resolution product would be fine; slightly blurring the latter would be optimal.
Ultimately, I think this is a good way to go. But I see no urgency for the path, since the value of the color is undercut by the assumption that it works partly due to the lack of color variation... But as long as it still works in cases where the color is useful, and I think it can, then this will become the path. Mastcam is paving the way for this, even with the unfortunate descopes. Others will follow.
Using a Sigma FOVEON sensor, http://en.wikipedia.org/wiki/Foveon_X3_sensor, where each pixel records all colors simultaneously, would avoid the interpolation problem.
According to Emily's twitter account, James Cameron is teaming up with Malin Space Science Systems to try and bring back the original zoom feature to Mastcam.
http://twitter.com/elakdawalla/status/11058862622
I really really really really really really really really really really really really really really really really really really really really really really really really really really really hope they can pull this off. I was hoping Cameron might help out with some of his Smurf money to rescope Mastcam so he could then get a 3D HD film out of it
Wow... that would propel MSL into a whole new catergory of cool, wouldn't it? Imagine the impact it would have if people could travel to Mars, virtually, in 3D, not just at an IMAX theatre but in their own local cinema a la AVATAR, etc. It could be the greatest leap forwards for Outreach, and for increasing public awareness of the worth of space exploration, for a generation.
Pleeeeeeeeeeeeeeeeeeeeeeeeeeeeease let that happen.
Fixed focus Mastcam has been delivered. MSSS "just started" building the zoomed version.
http://marsprogram.jpl.nasa.gov/msl/news/whatsnew/index.cfm?FuseAction=ShowNews&NewsID=990
http://www.msss.com/press_releases/mast_delivery/
That's the camera's first image, correct? Or were there some from before?
There is a Mastcam mosaic http://www.lpi.usra.edu/meetings/lpsc2010/pdf/1123.pdf
That swiss army knife photobombs all the MSSS promo shots!
Any word of progress with zoom-cam? Likely to be completed in time?
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