The Curiosity On Mars Thread.

Mountainsandh

slade_x

Sintel wrote: »

Thanks for that, but what I guess im really asking was how did they design/test/know that the powered descent stage would work? Like I said I've seen the drop test but not a test on the powered descent, I imagine it would be impossible to test on earth with the different environments, so would it have been based entirely on simulations (and a bit of luck)?

Good question, although i cant really answer that with any certainty but what i woud imagine they have tested is a mock up rig of the powered descent skycrane on earth with enough fuel, thrust etc. for earth parameters like gravity, atmospheric density etc. for testing stability for example (making sure the rockets were placed adequately for a stable landing). The calculations involved woudnt really need much practical testing as rocket science is now a proven and reliable discipline. Simulations may well suffice.

Unfortunately the only way to test the deployment of parameters with mars in mind would be just simulations based on calculations that have proven to work on earth. which is basically where rocket science knowledge obviously originates.

They would have done the same thing for the apollo lunar lander descent and ascent stages. To make sure the descent stage/ lander didnt crash into the lunar ground (exactly like making sure curiosity didnt crash into martian ground) and that the ascent stage could get back up into orbit around the moon to redock with the command module for the return trip home.

jumpjack

Mountainsandh wrote: »

is this picture of first laser shot?

Rubecula

If you are interested the next month's Sky At Night is about Curiosity on Mars.

shedweller

jumpjack wrote: »

is this picture of first laser shot?

I believe it is. No results back yet.

In other news, it looks like wheels will be turning on tuesday or wednesday this week.
http://www.space.com/17174-mars-rover-curiosity-first-drive-soon.html

The Curiosity rover is set to make its first tracks on the Red Planet Tuesday or Wednesday (Aug. 21 or 22), mission team members said. The maiden drive will be something of a test, so the 1-ton robot won't be allowed to stretch its legs right off the bat.
"Basically, we want to drive the wheels more than one rev in both directions," said Jeff Biesiadecki of NASA's Jet Propulsion Laboratory in Pasadena, Calif., one of Curiosity's 16 drivers. "What we've got sketched out right now is about a 4-meter drive forward, and about a 90-degree turn in place, and a couple meters backwards."
Everything looks good so far, researchers have said. It's now time to test out Curiosity's driving system, a stepwise process that begins today (Aug. 20) — Curiosity's 15th full day on the Martian surface, or Sol 15 in mission lingo. URL="http://www.space.com/16987-mars-rover-curiosity-photos-week-2.html"]Photos: Curiosity's 2nd Week on Mars[/URL
"On Sol 15, we're going to check out the steering actuators," Biesiadecki told SPACE.com. "We're going to run all the steering actuators one at a time — not through their entire range of motion but through both directions — and end them straight. So we should have all our wheels straight at the end of Sol 15."
If all goes well, the first drive should occur on Sol 16 (which begins Tuesday afternoon), Biesiadecki added. Curiosity will then pause to commemorate her first tentative steps on Mars.
"At the end of that maneuver, we'll be taking images of our tracks," Biesiadecki said. "We'll see the very beginning of our tracks, which I think is going to be kind of a cool picture."
The photography isn't just for historical or gee-whiz purposes, though. The team wants to see how much Curiosity sinks into the ground when it's on the move, Biesiadecki said.

We'll also see how gently the descent stage lowered the rover. From what i have seen, it barely sunk in the wheels. Which means the wheels and undercarriage are in top condition. Before the landing I had visions of the rover limping around with a bent wheel!

Mountainsandh

jumpjack wrote: »

is this picture of first laser shot?

Yes Jumpjack, it's the pic that goes with Sheddweller's update from Nasa above.

8mm hole but they can tell so much with that ! hopefully the discoveries will be easy enough to understand for a non-scientific person like me... and this one's only a test. Actually the square is 8mm so the hole must be even tinier, I'm sure size is mentioned somewhere...

shedweller

Going by the pic above i would guess that the hole created by the laser is about 0.5mm wide. I must emphasise "about"!!
I don't think i'm too far off though. It's less than 1mm.

Jawgap

From the BBC -

Rover panorama: Begin exploring Mars

"This is an interactive impression of the Curiosity rover and its Gale Crater landing site. It is built from a range of image sources, including early black and white images sent back to Earth by the one-tonne robot. One of the key landmarks, Mount Sharp, was constructed using this image."

shedweller

Robotic arm has been extended!


Only have thumbnails for now.

shedweller

A little extra information for you info geeks:
http://www.nasa.gov/mission_pages/msl/multimedia/gallery/PIA13388.html

The titanium arm has two joints at the shoulder, one at the elbow and two at the wrist. Each joint moves with a cold-tolerant actuator custom-built for the mission.
That toolkit, MAHLI, with a mass of about 33 kilograms (73 pounds), will include a percussive drill; a magnifying-lens camera; an element-identifying spectrometer; a rock brush; and mechanisms for scooping, sieving and portioning samples.

It's a big lump of stuff at the end of a rather long robotic arm so i hope the actuators are up to the job.

jaykay74

Wiggle in the gravel

This set of images shows the movement of the front left wheel of NASA's Curiosity as rover drivers turned the wheels in place at the landing site on Mars. Engineers wiggled the wheels as a test of the rover's steering and anticipate embarking on Curiosity's first drive in the next couple of days. This image was taken by one of Curiosity's Navigation cameras on Aug. 21.

http://www.nasa.gov/mission_pages/msl/multimedia/pia16087.html

shedweller

shedweller

Hard to tell if the shadow movement is due to movement of the rover, movement of the sun or both. It's the back wheel too, isn't it?

shedweller

MAHLI extended. Not that anyone needs telling!

shedweller

Atmospheric pressure varies quite regularly overnight!

slade_x

Wind sensor sustained damage in current official news 21/08/2012:

http://www.nasa.gov/mission_pages/msl/news/msl20120821b.html

One of the two sets of REMS wind sensors is not providing data. "One possibility is that pebbles lofted during the landing hit the delicate circuit boards on one of the two REMS booms," said Curiosity Deputy Project Scientist Ashwin Vasavada of NASA's Jet Propulsion Laboratory, Pasadena, Calif. "We will have to be more clever about using the remaining wind sensor to get wind speed and direction."

First drive scheduled for tomorrow and neutron shooting begun, also from same page

"Curiosity has begun shooting neutrons into the ground," said Igor Mitrofanov of Space Research Institute, Moscow, principal investigator for this instrument, called the Dynamic Albedo of Neutrons, or DAN. "We measure the amount of hydrogen in the soil by observing how the neutrons are scattered, and hydrogen on Mars is an indicator of water."

"Late tonight, we plan to send Curiosity the commands for doing our first drive tomorrow," said Curiosity Mission Manager Michael Watkins of JPL.

Jawgap

Boffins zapped '2,000 bugs' from Curiosity's 2 MILLION lines of code

From the Register.....

With a $2.5bn price tag, a 350-million mile journey and 2 million lines of C and some C++ code, the only bugs NASA wants its Curiosity rover to find are those possibly beneath the Martian surface.

And it may not be a particularly glamorous job, but software analysis outfit Coverity was the company tasked with "ensuring that every software defect is found and fixed before launch".

Roughly 2,000 bugs were zapped in the rover's code, estimates Andy Chou, the chief technical officer of Coverity, although NASA is schtum on the exact figures.

"For typical software (which this clearly isn't), it's not unusual to find approximately 1 defect for every thousand lines of code," Chou said. "For a project with 2 million lines of code, it would therefore not be unusual for Coverity to be able to find about 2,000 defects."

follow the link above for more.

namloc1980

Another MARDI sequence, this time centered on the heatshield:

https://www.youtube.com/watch?v=MlQGMbulf1o

Jawgap

Landing site is now officially called 'Bradbury Landing' - seems appropriate.....

shedweller

NASA's Mars rover Curiosity has begun driving from its landing site, which scientists announced today they have named for the late author Ray Bradbury. Making its first movement on the Martian surface, Curiosity's drive combined forward, turn and reverse segments. This placed the rover roughly 20 feet (6 meters) from the spot where it landed 16 days ago.
NASA has approved the Curiosity science team's choice to name the landing ground for the influential author, who was born 92 years ago today and died this year. The location where Curiosity touched down is now called Bradbury Landing.
"This was not a difficult choice for the science team," said Michael Meyer, NASA program scientist for Curiosity. "Many of us and millions of other readers were inspired in our lives by stories Ray Bradbury wrote to dream of the possibility of life on Mars."
Today's drive confirmed the health of Curiosity's mobility system and produced the rover's first wheel tracks on Mars, documented in images taken after the drive. During a news conference today at NASA's Jet Propulsion Laboratory in Pasadena, Calif., the mission's lead rover driver, Matt Heverly, showed an animation derived from visualization software used for planning the first drive.
"We have a fully functioning mobility system with lots of amazing exploration ahead," Heverly said.
Curiosity will spend several more days of working beside Bradbury Landing, performing instrument checks and studying the surroundings, before embarking toward its first driving destination approximately 1,300 feet (400 meters) to the east-southeast.

http://www.nasa.gov/mission_pages/msl/news/msl20120822.html

shedweller

Coronation's Chemicals

This is the first laser spectrum from the Chemistry and Camera (ChemCam) instrument on NASA's Curiosity rover, sent back from Mars on August 19, 2012. The plot shows emission lines from different elements present in the target, a rock near the rover's landing site dubbed "Coronation" (see inset).

ChemCam's detectors observe light in the ultraviolet (UV), violet, visible and near-infrared ranges using three spectrometers, covering wavelengths from 240 to 850 nanometers. The light is produced when ChemCam’s laser pulse strikes a target, generating ionized gases in the form of plasma, which is then analyzed by the spectrometers and their detectors for the presence of specific elements. The detectors can collect up to 16,000 counts produced by the light in any of its 6,144 channels for each laser shot.

The plot is a composite of spectra taken over 30 laser shots at a single 0.016-inch (0.4-millimeter) diameter spot on the target. An inset on the left shows detail for the minor elements titanium and manganese in the 398-to-404-nanometer range. An inset at the right shows the hydrogen and carbon peaks. The carbon peak was from the carbon dioxide in Mars' air. The hydrogen peak was only present on the first laser shot, indicating that the element was only on the very surface of the rock. Magnesium was also slightly enriched on the surface. The heights of the peaks do not directly indicate the relative abundances of the elements in the rock, as some emission lines are more easily excited than others.

A preliminarily analysis indicates the spectrum is consistent with basalt, a type of volcanic rock, which is known from previous missions to be abundant on Mars. Coronation is about three inches (7.6 centimeters) across, and located about 5 feet (1.5 meters) from the rover and about nine feet (2.7 meters) from ChemCam on the mast.

Jawgap

Wonder if it beeps when it reverses:D

Jawgap

shedweller wrote: »

A little extra information for you info geeks:
http://www.nasa.gov/mission_pages/msl/multimedia/gallery/PIA13388.html



It's a big lump of stuff at the end of a rather long robotic arm so i hope the actuators are up to the job.

Mars gravity is less then half of earth's so the instruments on the end of the arm should exert correspondingly less force - if the thing worked here it should work there. Dust could be a bit of a problem!

Capt'n Midnight

Jawgap wrote: »

Mars gravity is less then half of earth's so the instruments on the end of the arm should exert correspondingly less force - if the thing worked here it should work there. Dust could be a bit of a problem!

899Kg rover , mission cost $2.5bn

$2,780 per gram $78,836 per ounce.

it's worth 47 times it's weight in gold so they probably didn't spec the motor for earth gravity

Oldtree

got this in the email this am, pictures from mars, really fab:

Jawgap

Capt'n Midnight wrote: »

899Kg rover , mission cost $2.5bn

$2,780 per gram $78,836 per ounce.

it's worth 47 times it's weight in gold so they probably didn't spec the motor for earth gravity

How did they test it here then? all the components were tested to 3 x life. also the second rover they kept here presumably has to operate in our gravity so it's unlikely they specc'ed one set of actuators for the Mars rover and one for its earthbound buddy?

shedweller

There was a video recently, showing the mast erection procedure being tested. It looked like it was on the flight rover and not the earth bound one. I assume from that that the actuators are capable of working in earth gravity.
Still though, remember Spirit and the case of the sticky wheel that gave up the ...er....ghost (see what i did there?!)
Things can break no matter what.
Did anyone notice the rocker bogie system flexing during the steering test the other day? I know they can pivot up and down but i did see some side flex on the leg. Was that a joint moving or flex in what i imagine to be titanium legs?

thecommander

Footage of the heat shield falling away but with the shield image stabilised to the centre.

http://www.youtube.com/watch?v=MlQGMbulf1o

Turtwig

So Beautiful.

https://www.youtube.com/watch?v=e1ebHThBdlY

shedweller

Very Very Beautiful!:)

In other news:

These nutters keep popping up don't they!
http://www.nasa.gov/redplanet/angrybirds.html

NASA is helping pigs and birds explore the Martian terrain and shed light on the agency's missions to the Red Planet in the latest update to the game Angry Birds Space. Rovio Entertainment's update to Angry Birds Space is complete with a cast of agency rovers and landers.

Earlier this year, millions of gamers were introduced to concepts of microgravity in Angry Birds Space, which was supported through a partnership with NASA and includes links to a variety of education information.

"Rovio is teaching huge new audiences about NASA's missions to Mars thanks to this collaboration," said David Weaver, associate administrator for communications at NASA Headquarters in Washington. "It's a great way to introduce both kids and adults to the wonders of the planet in a fun and entertaining way."

NASA participated with Rovio on Angry Birds Space under a Space Act Agreement to share the excitement of space with the Angry Birds community, educate players about agency projects and programs, and collaboratively create interactive informational experiences for the public.

The game will include links to NASA web content about Mars exploration and NASA missions that are represented in the game. The content can be found here.

"We're huge NASA fans, and we were all cheering the Mars Curiosity rover as it touched down," said Peter Vesterbacka, chief marketing officer of Rovio Entertainment. "So, working together on the Mars update was a perfect fit, especially since we got such an amazing response to our previous collaboration, the 'Angry Birds Space: NASA announcement' video, which quickly surged to the top of 2012's viral video charts. We're thrilled to continue working with NASA. Stay tuned for even more great fun and educational content coming up."