The Technology of Curiosity

Saturday, September 01 2012 On April 14, 2004, NASA announced an opportunity for researchers to propose science investigations for the Mars Science Laboratory (MSL) mission. Eight months later, the agency announced selection of eight investigations. In addition, Spain and Russia would each provide an investigation through international agreements. The instruments for these ten investigations make up the science payload on the Curiosity rover.

Curiosity examines a rock on Mars with a set of tools at the end of its arm, which extends about 7 feet. Two instruments on the arm can study rocks up close. A drill can collect sample material from inside of rocks, and a scoop can pick up samples of soil. The arm can sieve the samples and deliver fine powder to instruments inside the rover for thorough analysis. (NASA/JPL-Caltech)

The ten instruments on Curiosity have a combined mass of 165 pounds. Curiosity carries the instruments plus multiple systems that enable the science payload to do its job and send home the results. Key systems include six-wheeled mobility, sample acquisition and handling with a robotic arm, navigation using stereo imaging, a radioisotope power source, avionics, software, telecommunications, and thermal control.

Curiosity is 10 feet long (not counting its arm), 9 feet wide, and 7 feet high at the top of its mast, with a mass of 1,982 pounds, including the science instruments. Curiositys mechanical structure provides the basis for integrating all of the other rover subsystems and payload instruments.

Mobility

Curiositys mobility subsystem is a scaled-up version of what was used on the three earlier Mars rovers: Sojourner, Spirit, and Opportunity. Six wheels all have driver motors, and the four corner wheels all have steering motors. Each front and rear wheel can be independently steered, allowing the vehicle to turn in place, as well as to drive in arcs. The suspension is a rocker-bogie system, enabling Curiosity to keep all its wheels in contact with the ground, even on uneven terrain. Curiositys wheels are aluminum and 20" in diameter. They have cleats for traction and structural support. Curving titanium spokes give springy support.

The rover has a top speed on flat, hard ground of about 1.5 inches per second. However, under autonomous control with hazard avoidance, the vehicle achieves an average speed of less than half that.

Arm and Turret

The Robot Arm (RA) is a five-degrees-of-freedom manipulator used to place and hold the turret-mounted devices and instruments on rock and soil targets, as well as manipulate the turretmounted sample processing hardware.

The science instruments on the arms turret are the Mars Hand Lens Imager (MAHLI) and the Alpha Particle X-ray Spectrometer (APXS). The other tools on the turret are components of the rovers Sample Acquisition/Sample Processing and Handling (SA/SPaH) subsystem: the Powder Acquisition Drill System (PADS), the Dust Removal Tool (DRT), and the Collection and Handling for In-situ Martian Rock Analysis (CHIMRA) device.

This drawing of Curiosity indicates the location of science instruments and some other tools. (NASA/JPL-Caltech)

The SA/SPaH subsystem is responsible for the acquisition of rock and soil samples from the Martian surface, and the processing of these samples into fine particles that are then distributed to the analytical science instruments SAM and CheMin. The SA/SPaH subsystem is also responsible for the placement of the two contact instruments, APXS and MAHLI, on rock and soil targets. SA/SPaH also includes drill bit boxes, the Organic Check Material (OCM), and an observation tray, which are all mounted on the front of the rover, and inlet cover mechanisms that are placed over the SAM and CheMin solid sample inlet tubes on the rover top deck.

The Powder Acquisition Drill System is a rotary percussive drill to acquire samples of rock material for analysis. It can collect a sample from up to 2" beneath a rocks surface. The drill penetrates the rock and powders the sample to the appropriate grain size for use in SAM and CheMin. If the drill bit becomes stuck in a rock, the drill can disengage from that bit and replace it with a spare. The Dust Removal Tool is a metal-bristle brushing device used to remove the dust layer from a rock surface or to clean the rovers observation tray.

A clamshell-shaped scoop collects soil samples from the Martian surface. The other turret-mounted portion of this device has chambers used for sorting, sieving, and portioning the samples collected by the drill and the scoop. An observation tray on the rover allows the MAHLI and the APXS a place to examine collected and processed samples of soil and powdered rock.

Power

Rover power is provided by a multi-mission radioisotope thermoelectric generator (MMRTG) supplied by the U.S. Department of Energy. This generator is essentially a nuclear battery that reliably converts heat into electricity. It consists of two major elements: a heat source that contains plutonium-238 dioxide, and a set of solid-state thermocouples that convert the plutoniums heat energy to electricity. It contains 10.6 pounds of plutonium dioxide as the source of the steady supply of heat used to produce the onboard electricity, and to warm the rovers systems during the Martian nights.

Computing

Curiositys mast features seven cameras: the Remote Micro Imager, part of the ChemCam suite; four black-and-white Navigation Cameras (two on the left and two on the right); and two color Mast Cameras (Mastcams). (NASA/JPL-Caltech)

Curiosity has redundant main computers, or rover compute elements. Of this A and B pair, it uses one at a time, with the spare held in cold backup. So, at a given time, the rover is operating from either its A side or its B side. Each computer contains a radiation-hardened central processor with PowerPC 750 architecture, a BAE RAD 750 processor operating at up to 200 MHz speed. Each of Curiositys redundant computers has 2 gigabytes of flash memory, 256 megabytes of DRAM, and 256 kilobytes of EEPROM. The MSL flight software monitors the status and health of the spacecraft during all phases of the mission, checks for the presence of commands to execute, performs communication functions, and controls spacecraft activities.

Navigation

Two sets of engineering cameras on the rover Navigation cameras (Navcams) up high, and Hazard-avoidance cameras (Hazcams) down low inform operational decisions both by Curiositys onboard autonomy software and by the rover team on Earth. Information from these cameras is used for autonomous navigation, engineers calculations for maneuvering the robotic arm, and scientists decisions about pointing the remote-sensing science instruments.

Each of the Navcams captures a square field of view 45 degrees wide and tall, comparable to the field of view of a 37-millimeter-focal-length lens on a 35- millimeter, single-lens-reflex camera. Curiosity has four pairs of Hazcams: two redundant pairs on the front of the chassis, and two at the rear. The rover can drive backwards as well as forward, so both the front and rear Hazcams can be used for detecting potential obstacles in the rovers driving direction. The Hazcams have one-time-removable lens covers to shield them from potential dust raised during the rovers landing.

Mast Camera (Mastcam)

This artists concept depicts Curiosity as it uses its ChemCam to investigate the composition of a rock surface. ChemCam fires laser pulses at a target and views the resulting spark with a telescope and spectrometers to identify chemical elements. The laser is in an invisible infrared wavelength, but is shown here as visible red light for purposes of illustration. (NASA/JPL-Caltech)

Two two-megapixel color cameras on Curiositys mast are the left and right eyes of the Mastcam. These cameras have complementary capabilities for showing the rovers surroundings in exquisite detail and in motion. The right-eye Mastcam looks through a telephoto lens with about three-fold better resolution than any previous landscape-viewing camera on the surface of Mars. The left-eye Mastcam provides broader context through a medium-angle lens. Each can acquire and store thousands of full-color images. Each is also capable of recording high-definition video.

The telephoto Mastcam is called Mastcam 100 for its 100-millimeter focal-length lens. The camera provides enough resolution to distinguish a basketball from a football at a distance of seven football fields. Its left-eye partner, called Mastcam 34 for its 34-millimeter lens, catches a scene three times wider on an identical detector.

Chemistry and Camera (ChemCam)

The ChemCam instrument consists of two remote sensing instruments: the first planetary science Laser-Induced Breakdown Spectrometer (LIBS), and a Remote Micro- Imager (RMI). The LIBS provides elemental compositions, while the RMI places the LIBS analyses in their geomorphologic context.

ChemCam uses a rock-zapping laser and a telescope mounted atop Curiositys mast. It also includes spectrometers and electronics inside the rover. The laser can hit rock or soil targets up to about 23 feet away with enough energy to excite a pinhead-size spot into a glowing, ionized gas called plasma. The instrument observes that spark with the telescope and analyzes the spectrum of light to identify the chemical elements in the target. The telescope doubles as the optics for the camera of ChemCam, which records monochrome images. The telescopic camera, called the remote micro-imager, will show context of the spots hit with the laser. It can also be used independently of the laser for observations of targets at any distance.

The spot hit by ChemCams infrared laser gets more than a million watts of power focused on it for five one-billionths of a second. Light from the resulting flash comes back to ChemCam through the telescope, then through about 20 feet of optical fiber down the mast to three spectrometers inside the rover. The spectrometers record intensity at 6,144 different wavelengths of ultraviolet, visible, and infrared light.

Alpha Particle X-Ray Spectrometer (APXS)The APXS on Curiositys robotic arm will identify chemical elements in rocks and soils. A pinch of radioactive material emits radiation that queries the target and an X-ray detector reads the answer. The instrument consists of a main electronics unit in the rovers body and a sensor head mounted on the robotic arm. Measurements are taken by deploying the sensor head towards a desired sample, placing the sensor head in contact or hovering, and measuring the emitted X-ray spectrum for 15 minutes to 3 hours without the need of further interaction by the rover.

Mars Hand Lens Imager (MAHLI)

MAHLI is a focusable color camera on Curiositys turret. Researchers will use it for magnified, close-up views of rocks and soils, and also for wider scenes of the ground, the landscape, or even the rover. Essentially, it is a handheld camera with a macro lens and autofocus.

The investigation takes its name from the type of hand lens magnifying tool that every field geologist carries for seeing details in rocks. MAHLI has two sets of white light-emitting diodes to enable imaging at night or in deep shadow. Two other LEDs on the instrument glow at the ultraviolet wavelength of 365 nanometers. These will make it possible to check for materials that fluoresce under this illumination.

This camera uses a red-green-blue filter grid like the one on commercial digital cameras for obtaining a full-color image with a single exposure. It stores images in an 8-Gb flash memory, and it can perform an onboard focus merge of eight images to reduce from eight to two the number of images returned to Earth in downlink-limited situations.

Chemistry and Mineralogy (CheMin)

CheMin is one of two investigations that will analyze powdered rock and soil samples delivered by Curiositys robotic arm. It will identify and quantify the minerals in the samples. CheMin uses X-ray diffraction, a first for a mission to Mars. It supplements the diffraction measurements with X-ray fluorescence capability to determine further details of composition by identifying ratios of specific elements present. X-ray diffraction works by directing an X-ray beam at a sample and recording how X-rays are scattered by the sample at the atomic level.

A sample processing tool on the robotic arm puts the powdered rock or soil through a sieve designed to remove any particles larger than 0.006 before delivering the material into the CheMin inlet funnel. Each sample analysis will use about as much material as in a baby aspirin.

Sample Analysis at Mars (SAM)

SAM is designed to explore molecular and elemental chemistry relevant to life. SAM addresses carbon chemistry through a search for organic compounds, the chemical state of light elements other than carbon, and isotopic tracers of planetary change. SAM is a suite of three instruments: a Quadrupole Mass Spectrometer (QMS), a Gas Chromatograph (GC), and a Tunable Laser Spectrometer (TLS). The QMS and the GC can operate together in a GCMS mode for separation (GC) and definitive identification (QMS) of organic compounds.

SAMs analytical tools fit into a microwave-oven-size box inside the front of the rover. While it is the biggest of the ten instruments on Curiosity, this tightly packed box holds instrumentation that would take up a good portion of a laboratory on Earth.

SAMs sample manipulation system maneuvers 74 sample cups, each about one-sixth of a teaspoon in volume. The chemical separation and processing laboratory includes pumps, tubing, carrier- gas reservoirs, pressure monitors, ovens, temperature monitors, and other components.

Rover Environmental Monitoring Station (REMS) REMS records six atmospheric parameters: wind speed/direction, pressure, relative humidity, air temperature, ground temperature, and ultraviolet radiation. All sensors are located around three elements: two booms attached to the rover Remote Sensing Mast (RSM), the Ultraviolet Sensor (UVS) assembly located on the rover top deck, and the Instrument Control Unit (ICU) inside the rover body.

Radiation Assessment Detector (RAD)

RAD will monitor high-energy atomic and subatomic particles reaching Mars from the Sun, distant supernovas, and other sources. These particles constitute naturally occurring radiation that could be harmful to any microbes near the surface of Mars or to astronauts on a future Mars mission. RAD is an energetic particle analyzer designed to characterize the full spectrum of energetic particle radiation at the surface of Mars. RADs measurements will help fulfill MSLs key goals of assessing whether Curiositys landing region has had conditions favorable for life and for preserving evidence about life.

Dynamic Albedo of Neutrons (DAN)

DAN is an active/passive neutron spectrometer that measures the abundance and depth distribution of H- and OHbearing materials in a shallow layer of Mars subsurface along the path of the rover. DAN can detect water bound into shallow underground minerals along Curiositys path. It shoots neutrons into the ground and measures how they are scattered, giving it a high sensitivity for finding any hydrogen to a depth of about 20" directly beneath the rover.

Mars Descent Imager (MARDI)

During the final few minutes of Curiositys flight to the surface of Mars, the Mars Descent Imager (MARDI) recorded a full-color video of the ground below. MARDI is a fixed-focus color camera mounted to the fore port side of the rover, even with the bottom of the rover chassis. The camera took images at 5 frames per second throughout the period of time between heat shield separation and touchdown. Throughout Curiositys mission on Mars, MARDI will offer the capability to obtain images of ground beneath the rover for tracking of its movements or for geologic mapping.

Learn more about Curiositys science instruments at http://mars.jpl.nasa.gov/msl/mission/science. View the latest videos of the Mars Science Laboratory and Curiosity rover on Tech Briefs TV at www.techbriefs.com/tv/mars. Get the latest news on the MSL mission at www.nasa.gov/mission_pages/msl/.

http://www.techbriefs.com/component/content/article/14715NASA Begins a New Journey of Exploration

Saturday, September 01 2012 Tonight, on the planet Mars, the United States of America made history. The successful landing of Curiosity the most sophisticated roving laboratory ever to land on another planet marks an unprecedented feat of technology that will stand as a point of national pride far into the future. It proves that even the longest of odds are no match for our unique blend of ingenuity and determination. Tonights success reminds us that our preeminence not just in space, but here on Earth depends on continuing to invest wisely in the innovation, technology, and basic research that has always made our economy the envy of the world. I congratulate and thank all the men and women of NASA who made this remarkable accomplishment a reality and I eagerly await what Curiosity has yet to discover.

- President Barack Obama, August 6, 2012 At 1:32 a.m. EDT on August 6, NASAs Mars Science Laboratory (MSL) touched down on the Red Planet, beginning a two-year mission of exploration and discovery. The Curiosity rover is a mobile laboratory equipped with 10 science investigations and a robotic arm that can drill into rocks, scoop up soil, and deliver samples to internal analytical instruments. (For detailed information on Curiositys instruments, see the feature beginning on page 28.)

The spacecrafts descent stage, while controlling its own rate of descent with four of its eight throttle-controllable rocket engines, begins lowering Curiosity on a bridle. The rover is connected to the descent stage by three nylon tethers and by an umbilical, providing a power and communication connection. The bridle extends to full length, about 25 feet, as the descent stage continues descending. Seconds later, when touchdown is detected, the bridle is cut at the rover end, and the descent stage flies off to stay clear of the landing site. (NASA/JPL-Caltech)

Following a harrowing seven minutes of terror in which Curiosity had to survive a dive that took it from 13,200 miles per hour to zero, the rover touched down and immediately began sending back images from its landing spot in Gale Crater.

Said MSL project scientist John Grotzinger, Curiosity is not a life-detection mission. Were not actually looking for life. We dont have the ability to detect life if it was there. What we are looking for are the ingredients of life.

MSL will study whether the Gale Crater area has evidence of past and present habitable environments. These studies will be part of a broader examination of past and present processes in the Martian atmosphere and on its surface.

Curiosity will rely on new technological innovations. For its landing, the spacecraft descended on a parachute and then, during the final seconds prior to landing, lowered the upright rover on a tether to the surface, much like a sky crane. Now on the surface, the rover will be able to roll over obstacles up to 29 inches high, and travel up to 295 feet per hour. On average, the rover is expected to travel about 98 feet per hour, based on power levels, slippage, steepness of the terrain, visibility, and other variables.

This full-resolution image shows part of the deck of Curiosity taken from one of the rovers Navigation cameras looking toward the back left of the rover. On the left, part of the rovers power supply is visible. To the right of the power supply is the pointy low-gain antenna and side of the paddle-shaped high-gain antenna for communications directly to Earth. (NASA/JPL-Caltech)

To make best use of the rovers science capabilities, a team of scientists and engineers will make daily decisions about the rovers activities for the following day. MSL is intended to be a discovery-driven mission, with the science operations team retaining flexibility in how and when the various capabilities of the rover and payload are used to accomplish the overall scientific objectives.

Curiosity landed in a region where a key item on the checklist of lifes requirements has already been determined: It was wet. Observations from Mars orbit during five years of assessing candidate landing sites have made these areas some of the most intensely studied places on Mars.

While the possibility that life might have existed on Mars provokes great interest, a finding that conditions did not favor life would also pay off with valuable insight about differences and similarities between early Mars and early Earth.

Learn more about Curiositys mission at http://mars.jpl.nasa.gov/msl.

http://www.techbriefs.com/component/content/article/14713Talking Mars

Saturday, September 01 2012 Page 1 of 3

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NASA Tech Briefs recently spoke with Doug McCuistion, Director of the Mars Exploration Program, and Michael Meyer, lead scientist for the Mars Exploration Program and Program Scientist for the Mars Science Laboratory (MSL). We talked about what NASA hopes to find, the technologies used onboard, and how the two-year mission is expected to progress. NASA Tech Briefs: What are the science objectives for the Mars Science Laboratory?

Michael Meyer: The overarching goal of the Mars Science Laboratory and rover Curiosity is to understand whether Mars has ever been, or is capable today, of supporting microbial life. So thats another way of saying we want to determine the habitability of Mars. There are other things that can be discovered by Curiosity as it roves about, but thats the overall goal and how it was designed.

NTB: Why was Gale Crater selected as the landing site?

Michael Meyer, lead scientist for the Mars Ex - ploration Program and Program Scientist for MSL.

Meyer: Over the past five years, the science team got together, people proposed what they considered were very interesting landing sites, and then there were discussions about how interesting it is to everybody else. As we narrowed it down, we also got into how safe it is, does the landing ellipse fit inside a good place, and are there rocks.

The science community had to be self-policing about what it could actually do and what it could reasonably speculate. This is one of the things we really benefit from the amount of information we got from having a Mars program. We ended up picking Gale Crater because it has Mount Sharp in the middle this huge mound that should have an extensive history of Mars starting from more than three billion years ago to whatever Mars is like at present.

NTB: This is the first time since the Viking landings in 1976 that NASA has used throttleable engines for landing a Mars spacecraft. Why was this method chosen for MSL?

Doug McCuistion: The engines are a new design based on a heritage unit. Because of the throttleable nature and the amount of thrust we can get from these, they make a great engine for orbiters for certain Mars orbit insertions as well. So, well use these again, maybe next time on an orbiter.

Doug McCuistion, Dir ec tor of the Mars Exp loration Program.

There were a lot of things chosen because of the additional mass of MSL. Airbags max out around 200 kg, so the airbag technology couldnt handle a rover of this mass. So we had to come up with a new technique. The concept was a larger parachute to get more drag, and obviously a larger entry shell that reduces our speed and also is volumetrically necessary. But once we got done with the parachute, the replacement for the airbags had to be something that could handle a 1,000-kg rover underneath it, to be able to take out both horizontal and vertical velocities. So instead of putting the engines underneath it like Viking, we decided to put the engines on top.

NTB: Curiosity is NASAs largest and most complex rover. Other than size, how does it differ from Opportunity and Spirit?

McCuistion: Its very different probably the two biggest differences are the payload capability and the power source. Essentially, the plutonium 238-powered radioisotope thermal generator is a constant power source, regardless of time of day. Were not dependent upon solar energy any longer. Weve got a constant feed of power, with a constant output of about 110 Watts. That gives us a great capability to charge batteries overnight, to be able to rove farther, and to be able to last longer on the surface by design. Thats a fantastic capability because of the power source. For the instruments, weve gone from less than 6 kg of instruments to over 80 kg of instruments, comparing the MER (Mars Exploration Rover) rovers to the MSL rover.

Meyer: The key difference is that Curiosity is a roving analytical laboratory. There are two instruments in the interior of the rover that are major instruments. For Spirit and Opportunity, all of the instrumentation was remote and contact instruments, while Curiosity has two analytical instruments inside.

On the interior, we have an instrument called CheMin (Chemistry and Mineralogy), which is an x-ray diffraction/x-ray fluorescence instrument that measures the distance between atoms. This is the same kind of instrument youd have in a laboratory. Mineralogy is important because it tells you the environment in which the rock was formed. The other instrument is SAM (Sample Analysis at Mars), and thats a gas chromatograph mass spectrometer. This gives you composition it tells you what things are made out of. Its not the elements, but also the smaller compounds. It also can do isotopes. In addition, SAM has whats called a tunable laser system (TLS), which is a spectrometer that can measure certain things to an extreme degree. It can measure carbon dioxide, water, and also methane, which is probably the one were most excited about.

The other instrument thats unique is the ChemCam (Chemistry and Camera suite), which is a laser-induced breakdown spectrometer. It fires a laser, creates a plasma, and then uses a spectrometer to look at the plasma and tell what the composition is. Its a remote sensing instrument, so you dont have to place the instrument against whatever youre interested in. You can do it within 7 meters of the rover.

NTB: Are there other minerals youre looking for besides carbon and methane?

McCuistion: This mission is highly unusual in that weve already targeted minerals that we see from orbit. We see sulfates and we see clays, both of which are minerals that form in water, and they also represent slightly different environments. Clays form in a neutral environment with a pH around 7, while sulfates tend to form in more acidic environments and you also find them, at least on Earth, in environments where the water is drying out. Those are good indicators that were going to go to a place where we have mineral deposits that were laid down when Mars was warmer and wetter, and mineral deposits that were laid down when Mars was drying out. As you go further up Mount Sharp, well find things that are indicative of modern Mars, which is cold and dry.

NTB: What are the first steps in Curiositys commissioning phase?

McCuistion: After it does its health check and everythings working, it recalibrates its thermal model to make sure it has the right energy budget for managing things. Its then going to move into a mode of first-time events. The team will move it a little bit and then say, OK, we told it to move a foot did it move a foot? But these things come much later. Things wont happen right away this is all within the first 30 days. For each instrument, the team will turn it on and see if its working, and put it through its own personal health check. Theyll make a measurement, see what the measurement says, and if it corresponds to whats expected. Pathfinder, Phoenix, and MER landed on the surface and they were expected to live 90 to 120 days. So it was, We better get on with it, because we dont have much time. MSL is designed as a two-year mission. Its a long-life mission and its going to take a couple of months to really get this thing fully commissioned before its fully operational.

NTB: What is Curiositys expected range of travel?

McCuistion: Spirit and Opportunity have proven to us that any predictions are completely useless. From an engineering perspective, its how long the mechanical systems last. Thats really the limiting factor. The power source will give us many, many years on the surface of nice, clean, consistent power. The rover is designed to be able to travel 20 kilometers. The reason for that is its designed to be able to get out of its landing ellipse. What that does is enable the mission to have a goal to go see something it cant land on. And in fact, thats Mount Sharp. It has to be able to travel a good distance to be able to get there.

NTB: Are the decisions of the science team as far as where Curiosity will go each day determined according to what findings were made the previous day?

McCuistion: Yes, this is actually unique and exciting at the same time. There is a Science Operations Working Group and essentially, every day, they find out what the rover did yesterday did it do what it was supposed to do, and did it find something particularly exciting. They analyze the data and have a debate about what to do tomorrow. So filtering into the tactical decision about what to do each day will be are we still headed in the right direction to meet our strategic objective?

NTB: Curiosity has a payload of 10 instruments. Can you briefly describe some of them?

Meyer: Well characterize the modern environment of Mars very well. We have whats basically a weather station contributed by the Spanish. Well also be measuring neutrons and return of neutrons from a neutron generator (Dynamic Albedo of Neutrons, DAN) that tells us how much water there is in about the upper meter of the regolith, and thats contributed by the Russians. We have an alpha particle x-ray spectrometer (APXS) that is similar to whats on the Mars Exploration Rovers that gives us elemental composition from contact. Its provided by the Canadians.

The Mars Hand Lens Imager, MAHLI, is different in that it has its own light source, so it has a better magnification field to see things down to about 14 microns. It can see at night so if there are any fluorescent minerals, it will be able to detect those.

The MastCam is interesting in that not only is it stereo, but also it has a filter wheel so it gives you different colors. Well finally resolve the debate about if youre on Mars, what color would the sky be? It has a huge amount of memory. It can take a high-resolution picture of everything and then send back thumbnails. The science team can say, We really like this rock, and instead of having to ask the camera to go look at that rock and take a picture, you just ask the system to send you back the highresolution picture of it. The pictures already taken its whether or not you request the data.

Curiosity also has a drill for sampling (PADS, Powder Acquisition Drill Sys tem). Well be able to get below the veneer thats on rocks and sample the interior of the rock. That will be particularly useful for the analytical laboratory thats in the rover. It will be able to take those, determine mineralogy, and also composition. Because we havent done that before, it may provide some real surprises.

NTB: Are there potential commercial applications for these types of instruments?

McCuistion: We already have one example, which is the CheMin. It already has a commercial version called Xterra. Its a suitcase you can carry into the field to measure metals. I would expect that, for instance, ChemCam (the laser-induced breakdown spectrometer) might be very useful. Some people might be worried about carrying around a laser in a suitcase, but I can imagine that being a useful tool here on Earth.

Other things like SAM there may be some commercial spinoffs just because of the efforts its gone through for miniaturization. It is taking a laboratory instrument that everybodys happy with, and shrinking it down so that it fits in a box.

One of the things thats unique about Curiosity is it will be able to measure organic compounds. One of the big surprises from Viking was not finding any organic compounds. You expect to find at least some because you get them from meteorites, if nothing else. So thats going to be a big issue for Curiosity.

NTB: The Navcams and Hazcams enable Curiosity to navigate and see where its going. What other types of hazard avoidance measures are in place?

McCuistion: MSL has gained a lot from the Spirit and Opportunity rovers, and thats in regard to autonomous software. It has a lot of software onboard that can actually navigate and recognize hazards autonomously and either navigate around them or decide its too complicated to do that, and just wait for Earth to help it. The rover driver and navigation teams use the cameras on a regular basis to understand the rovers surroundings and identify safe paths of traverse. The most important portion of that capability is the autonomous software aboard that helps us with navigation.

The rover also has accelerometers and inclinometers in the system, so it understands what its own tilt and roll angles are. So, as it climbs Mount Sharp, if it reaches limits of tilt and roll, the inclinometers tell the system its at its limits so it does not roll. The whole rocker-bogie system has a design that goes all the way back to the Sojourner rover, and is an extremely capable and flexible system.

Meyer: Just to add to what Doug said about software navigation, right now, you can take your images from a Mastcam or Navcam and plot out, safely, about 30 meters. And then after that, your imagery is too planar and you cant really decide what would be the best path to go. So the rover itself has to decide that. One of the things that has been developed from MER is navigation software that is able to take images as the rover goes along and say, OK, thats a big rock turn to the left. Thats why the Mars Exploration Rovers have been able to go up to 100 meters. Curiosity will benefit from that.

McCuistion: Thats the advantage of the longevity of Spirit and Opportunity. I think people dont realize the advancements in surface navigation that are only possible because Spirit and Opportunity survived for so long; that we could build new software tools, new concepts, new techniques, and then test them, upload them, and use them. Its been spectacular, not just scientifically, but from an engineering perspective, what Spirit and Opportunity were able to do and port into MSL.

NTB: The Radiation Assessment Detection (RAD) instrument was taking measurements during the trip to Mars. What has it found that you didnt know before?

McCuistion: The RAD is designed for a broad spectrum of high-energy radiation measurement, and it was turned on about a week after launch. It was turned off on July 13, getting ready for entry, descent, and landing. Whats interesting about RAD measuring in transit is that it sees what might be seen by an astronaut on his way to Mars. One of the concerns about high-energy radiation is what gets shielded by the spacecraft, and also what gets generated by the spacecraft. So, high-energy particles impinging on the cruise stage actually generate secondary particles that may be just as harmful, but of a different nature. RADs been able to measure those.

NTB: What have you already learned from MSL for future Mars missions?

McCuistion: Scientifically, weve already got a data set from RAD that weve never had before, which is the true radiation levels, dosages, etc., that astronauts might see in space in transit to Mars. From an engineering perspective, weve learned an enormous amount about how to build a system of this capacity and capability. The sky crane technique is a great technique for being able to put larger and larger masses on the surface, and frankly, as a feed-forward technology capability, you could foresee this putting all kinds of different scientific systems on the surface and potentially even re-supply for astronauts on the surface sometime in the future. We have learned to shrink instruments dramatically, changing their footprints significantly, which will always pay off in future scientific missions, whether they are on Mars or some other location.

Guided entry is another one the ability to shrink the landing ellipse so significantly that we can get into areas that we couldnt have imagined ten years ago. That opens up science portals that we cant even fathom at this point. There are pretty exciting opportunities.

Meyer: With MARDI, the Mars Descent Imager, one of the big debates was whether or not, because of thruster plume, youll get useful images. So who cares, other than the scientists who have to figure out where youre going? Well, one of the derived benefits of decent images would be for terrain recognition, which means in the future you could say, I want to land right over here next to that rock, and you can have the software look at the images and actually plan exactly where you want to go. And that will make a big difference when we do sample return or we send humans to Mars, when you want them to land next to where we put the foodstuffs.

McCuistion: The other thing is the heat shield material. The heat shield material is called PICA (Phenolic Impregnated Carbon Ablator) and we adopted it for use when we saw what kind of mass we were dealing with and what the heating rates were. PICA was a lot safer and gave us a lot more margin. This will be the first time its actually been used. This is a potential heat shield material for human exploration in the future.

http://www.techbriefs.com/component/content/article/14714