 
[musical tones]
[electronic sounds of data]
- WELCOME TO
THE 75TH ANNIVERSARY
OF NASA AMES RESEARCH CENTER
DIRECTOR'S COLLOQUIUM
SUMMER SERIES.
TODAY'S SEMINAR IS
BY DR. RAJ VENKATAPATHY
AND IS TITLED
"MARY POPPINS APPROACH
TO HUMAN MARS MISSION ENTRY,
DESCENT, AND LANDING."
EVERY NASA SPACECRAFT
THAT HAS ENTERED
ANOTHER PLANET'S ATMOSPHERE
OR RETURNED TO LAND ON EARTH
USES TECHNOLOGIES DEVELOPED
AT NASA AMES RESEARCH CENTER.
AS WE EXPAND OUR VISION
OF SPACE EXPLORATION,
A STOWABLE, COMPACT ENTRY SYSTEM
THAT IS SCALABLE,
IS ESSENTIAL FOR BOTH MANNED
AND UNMANNED MISSIONS.
TODAY'S TALK WILL DISCUSS
A NOVEL ENTRY, DESCENT,
AND LANDING SYSTEM
CALLED "ADEPT."
RAJ IS THE CHIEF TECHNOLOGIST
FOR THE ENTRY SYSTEM
AND TECHNOLOGY DIVISION
AT NASA AMES RESEARCH CENTER.
HE IS ALSO THE PROJECT MANAGER
FOR THE GAME-CHANGING
THERMAL PROTECTION SYSTEM
MATERIALS DEVELOPMENT PROJECT
AND THE CO-INVENTOR OF "ADEPT."
PRIOR TO JOINING
NASA AMES RESEARCH CENTER,
HE WAS THE PRESIDENT
AND DIRECTOR OF RESEARCH
FOR ELORET CORPORATION.
HE RECEIVED HIS DOCTORAL DEGREE
FROM IOWA STATE UNIVERSITY
ON THE DEVELOPMENT
AND APPLICATION
OF A COMPUTATIONAL
FLUID DYNAMICS SOLVERS
TO PREDICT HYPERSONIC FLOW
AROUND THE SHUTTLE ORBITER.
PLEASE JOIN ME IN
WELCOMING DR. VENKATAPATHY.
[audience applause]
- GOOD AFTERNOON, EVERYBODY.
[clears throat]
THANK YOU, DR. COHEN.
IT'S A GREAT HONOR TO BE PART
OF THE SUMMER SERIES,
ESPECIALLY
THE 75TH ANNIVERSARY
DIRECTOR'S COLLOQUIUM HERE.
THE SPEAKERS THAT ARE GOING
TO FOLLOW THE SUMMER,
THEY'RE VERY GREAT PEOPLE,
ACCOMPLISHED PEOPLE.
AND IT'S VERY--I'M VERY
HONORED TO BE HERE
AND TALKING TO ALL OF YOU,
ESPECIALLY MY COLLEAGUES
THAT ARE HERE,
THAT HAVE BEEN LIVING
THIS STORY
I'M GOING TO TELL YOU.
AND WITHOUT MUCH,
I'VE BEEN ASKED TO GIVE
A LITTLE BIT
ABOUT MYSELF FIRST.
SO I WAS BORN IN INDIA
IN A CITY CALLED MADRAS.
AND I DID
MY UNDERGRADUATE DEGREE
IN AERONAUTICAL ENGINEERING.
AND THEN I CAME TO U.S.
I DON'T KNOW HOW MANY
OF YOU KNOW
WHERE IOWA IS AND AMES IS.
SO I THOUGHT I'LL SHOW
A LITTLE VIDEO
OF WHERE MADRAS IS.
THAT'S WHERE I CAME.
DES MOINES IS
THE CAPITAL OF IOWA STATE.
AND IOWA STATE UNIVERSITY
IS VERY CLOSE TO DES MOINES.
AND AMES IOWA AND NASA AMES
HAD A TRADITIONAL CONNECTION
IN AN AREA CALLED
COMPUTATIONAL FLOW DYNAMICS.
THAT'S WHERE I SPECIALIZED.
AND I WORKED
AT LANGLEY RESEARCH CENTER
FOR A YEAR AFTER I GRADUATED.
AND I LOVE HIKING,
BACKPACKING, PHOTOGRAPHY,
AND ALSO EATING GOOD FOOD.
OVER THE YEARS,
I'VE GAINED SOME WEIGHT.
I'M TOLD THAT I NEED TO
THINK ABOUT--
SO I'LL GO BACK
TO HIKING AND BACKPACKING.
I LOVE PHOTOGRAPHY AND SOME OF
THESE ARE OF MY FAVORITE PLACES.
AND HAWAII IS
ANOTHER FAVORITE PLACE
TO BE ON THE BEACH WITH MY WIFE,
WHO IS HERE SOMEWHERE.
WE'VE BEEN MARRIED
FOR 29 YEARS.
AND THAT'S PRETTY MUCH
ABOUT MYSELF.
THE TITLE OF THE TALK,
"MARY POPPINS APPROACH--"
IF YOU ARE BORN
IN THE LAST CENTURY,
YOU WOULD KNOW MARY POPPINS.
AND I DON'T KNOW
HOW MANY OF YOU
THAT ARE HERE TODAY ARE BORN
IN THIS CENTURY.
AND IT'S A GREAT STORY
FOR CHILDREN, IMAGINATION.
AND IF YOU SEE HER,
AT THE END OF THE TALK,
YOU'LL KNOW WHY
I SELECTED THIS
AS THE TOPIC FOR
OUR CONVERSATION TODAY.
MARS--THAT'S ALSO
AN AMAZING PLACE,
AMAZING STORY
UNFOLDING FOR CENTURIES.
AND THAT'S A PICTURE
OF MARS THAT YOU SEE,
THE FROSTY WHITE CLOUDS--
ICE CLOUDS--
AND THE DUSTY STORM.
IT WAS TAKEN BY
HUBBLE TELESCOPE IN 2004.
AND WE HAVE LEARNED
A LOT FROM THE ROVERS
THAT ARE ROVING
AROUND MARS TODAY.
VERY QUICKLY, LAST CENTURY--
IT'S VERY INTERESTING
TO THINK OF MYSELF
AS I WAS BORN
IN LAST CENTURY,
AND I'M IN THIS CENTURY
NOW WORKING ON THINGS.
THE LAST CENTURY, HUMANS LEFT
THE SURFACE OF EARTH.
THE FIRST AIRPLANE
TO ALL THE WAY
TO GOING TO THE MOON
WERE ALL ACCOMPLISHED.
AND THEN WE BUILT
THE SPACE STATION.
HUMAN PRESENCE EXPANDED
INTO NEAR-EARTH ORBIT.
STILL, THE GRAVITY WELL
WAS KEEPING US
TOO CLOSE TO EARTH.
MARS.
[clears throat]
WE WERE SUCCESSFUL
AFTER MANY TRIALS AND ERRORS
TO PUT ORBITER ON MARS,
AND THEN WE PUT LANDERS.
BETWEEN 1976 AND '97,
THERE WAS A PERIOD
WHERE WE DIDN'T THINK
ABOUT MARS
BECAUSE WE WERE BUILDING
THE SPACE SHUTTLE
AND SPACE STATION,
AND ALL OUR FUNDING
WENT TOWARDS THOSE TWO.
AND STARTING
IN '97, '96 OR SO,
WE STARTED
EXPLORING MARS AGAIN.
AND THIS CENTURY,
WE LANDED MULTIPLE ROVERS--
THE M.E.R.,
THE TWO TWIN ROVERS,
"PHOENIX," AND "CURIOSITY."
I THINK MOST OF YOU
HAVE SEEN THE MOVIE,
THE "SEVEN MINUTES OF TERROR,"
ABOUT "CURIOSITY" LANDING
ON MARS.
I WILL COVER PART
OF THAT IN MY TALK.
BUT THAT WAS
A GREAT ACCOMPLISHMENT.
ALL OF THAT IS
IN PREPARATION
FOR HUMANS GOING TO MARS
IN THE LONGER TERM.
ON THE HUMAN SIDE,
SHUTTLE WAS RETIRED.
AND IT WAS--BECAUSE I WORKED
ON SHUTTLE
BEFORE SHUTTLE FLEW
ABOUT HYPERSONIC FLOW.
THAT WAS NOT A GREAT DAY
PERSONALLY FOR ME.
BUT HOPEFULLY OUR PRESENCE
IN SPACE WILL EXPAND
BEYOND LOW-EARTH ORBIT
IN THE NEAR FUTURE.
AND I AM VERY, VERY BLESSED
TO BE WORKING ON THOSE THINGS.
SO THAT'S WHAT THIS
TALK IS GOING TO BE.
SO I'M GOING TO DESCRIBE
ESSENTIALLY
WHAT ARE THE CHALLENGES
FOR HUMAN EXPLORATION
AND SPECIFICALLY
CONNECTED WITH MARS.
I'LL SHOW YOU
A COUPLE OF THE CONCEPTS
THAT NASA IS WORKING ON.
AND I'LL FOCUS MOSTLY
ON ONE CONCEPT
THAT WE ARE DEVELOPING HERE.
AMES IS TAKING THE LEADERSHIP
OF THAT CONCEPT DEVELOPMENT.
IT INVOLVES
OTHER NASA CENTERS AS WELL.
AND HUMAN EXPLORATION OF MARS
IS A LONG JOURNEY, REALLY.
NOT JUST PHYSICAL TIME,
BUT ALSO IN TERMS
OF FUNDING AND TECHNOLOGIES
AND SO ON.
SO THE CONCEPT
WILL ALSO BE--
IS BEING EXPLORED
FOR OTHER APPLICATIONS.
I'LL COVER THEM IN THE TALK.
OUR CENTER DIRECTOR--
THE MOTIVATION, REALLY,
THE VISION
FOR MARS EXPLORATION--
PERIODICALLY, WE VISIT THEM,
WE REAFFIRM THAT,
AND HERE IS
A COUPLE OF PEOPLE
THAT YOU ALL RECOGNIZE.
AND IF I CAN GET THIS--
I SHOULD HAVE PRACTICED BEFORE.
OKAY.
I THINK I'M FIGURING
THIS OUT NOW.
- FIGURE OUT WHETHER
THERE'S LIFE
OTHER PLACES
IN THE SOLAR SYSTEM.
BUT MORE FUNDAMENTALLY WHAT
WE'RE ALL ABOUT AT NASA
IS FIGURING OUT
HOW TO EXTEND
HUMAN PRESENCE
IN THE SOLAR SYSTEM.
- AND IF WE--
OUR ADMINISTRATOR.
- SPACECRAFT AND ROVERS ARE
ALREADY ON AND AROUND MARS,
DRAMATICALLY INCREASING
OUR KNOWLEDGE
ABOUT THE RED PLANET
AND PAVING THE WAY
FOR FUTURE HUMAN EXPLORERS.
FUTURE MISSIONS,
SEEKING SIGNS OF PAST LIFE,
WILL DEMONSTRATE
NEW TECHNOLOGIES
THAT COULD HELP ASTRONAUTS
SURVIVE ON MARS.
- I THINK SOME OF
THE MOST AMAZING THINGS
THAT WE'RE LEARNING
ARE ACTUALLY
HOW TO BE
REALLY GOOD DETECTIVES
ON ANOTHER PLANET, WHICH IS
A REALLY DIFFICULT JOB.
- ENGINEERS AND SCIENTISTS
AROUND THE COUNTRY
ARE WORKING HARD TO DEVELOP
THE TECHNOLOGIES
ASTRONAUTS WILL USE TO ONE DAY
LIVE AND WORK ON MARS
AND THEN SAFELY RETURN HOME
FROM THE NEXT GIANT LEAP
FOR HUMANITY.
- THROUGH ADVANCED AEROSPACE
TECHNOLOGIES
USED IN EVERYTHING
FROM MODERN AIRCRAFT
TO SUBORBITAL ROCKETS
AND THE COMMERCIAL VEHICLES
SERVICING LOW-EARTH ORBIT TODAY,
WE'RE BUILDING THE MACHINES
TO TAKE US FARTHER
INTO THE HIGH FRONTIER.
[rocket boosters whooshing]
NASA IS HERE TO RAISE
THE BAR FOR HUMAN ACHIEVEMENT.
WE'RE A COMMUNITY DEDICATED
TO RESEARCH AND DISCOVERY
IN SERVICE TO SOCIETY.
WE HAVE A RESPONSIBILITY
TO THE FUTURE GENERATIONS,
TO THE FUTURE GENERATIONS
OF ENGINEERS, SCIENTISTS,
TECHNOLOGISTS, EXPLORERS.
THAT'S OUR CHALLENGE.
- [laughs]
- WE'RE HAVING FUN!
- SO IN SOME SENSE,
THOSE MISSION STATEMENTS
ARE VERY IMPORTANT FOR US TO,
FIRST BELIEVE IN THEM,
AND THEN
HOW DO WE ACHIEVE THEM?
WHEN WE LOOK
AT REALIZING THE VISION
STATED BY LEADERSHIP,
WE SEE A LOT OF CHALLENGES.
WE HEAR ABOUT HUMAN MARS
MISSIONS IN THE NEWSPAPER,
PERIODICALLY ABOUT HOW
EXPENSIVE IT'S GOING TO BE,
WHETHER THERE'S
POLITICAL SUPPORT OR NOT.
BEYOND THOSE, THERE'S
ALSO TECHNICAL CHALLENGES.
THAT'S PRIMARILY
THE SENSE OF THIS TALK.
TECHNICAL CHALLENGES--IF YOU
LOOK AT IN THE BIG PICTURE,
INTERPLANETARY TRAVEL,
ESPECIALLY FOR HUMANS,
IT'S NOT VERY WELL UNDERSTOOD.
WE HAVE LIVED IN THE STATION
FOR EXTENDED PERIOD OF TIME.
STATION IS
SOMEWHAT PROTECTED
FROM THE DEEP SPACE RADIATION.
AND IF YOU LOOK AT ENTRY,
DESCENT, LANDING,
WHICH IS--I'M GOING
TO TALK ABOUT
AND SHOW YOU WHY
IT'S A BIG CHALLENGE,
THAT'S ANOTHER--AND SURVIVAL
AT THE SURFACE.
WHEN YOU GET THERE,
YOU REALLY HAVE TO
CARRY ALL THE RESOURCES.
THAT MEANS AN AMOUNT OF MASS
YOU HAVE TO CARRY WITH YOU
OR AHEAD OF THE HUMAN PERSON.
THOSE ARE ALL CHALLENGES.
AND THEN ANY EXPLORER--
IF THEY DON'T RETURN BACK
TO THE ORIGIN OF WHERE
THEY STARTED THEIR JOURNEY FROM,
THEY DON'T GET TO TELL
THE STORY.
SO WE'VE GOT TO BRING
THE ASTRONAUTS BACK SAFELY.
AND THAT'S ANOTHER CHALLENGE
AS WELL.
AND THE NASA VISION TODAY,
AS STATED BY
OUR ADMINISTRATOR BY NASA,
IS REALLY THAT NEAR EARTH--
OUR ABILITY TO BE IN SPACE
IS GOING TO BE DONE
BY COMMERCIAL CREW,
COMMERCIAL ENTITIES,
COTS PROGRAM.
BUT GOING BEYOND EARTH'S
VICINITY,
THE PLANS ARE TO MATURE.
AS YOU SEE, MISSIONS THAT ARE
BEING PLANNED
IS IN THE ORDER OF MONTHS
TO BE OUT THERE
AND COME BACK.
AND THEN WE HAVE
TO GET READY FOR MARS.
AND MARS MISSIONS WILL BE
TWO TO THREE YEARS LONG.
WE NEED TO DEMONSTRATE
TECHNOLOGIES
THAT ARE GOING TO CARRY US
TOWARDS MARS BY DOING
TECHNOLOGY DEMONSTRATION
AND SO ON AND SO FORTH.
SO THE CURRENT PLAN IS
EVOLVING.
IT'S CONSTRAINED BY BUDGET
AND SO ON AND SO FORTH.
BUT OUR JOB, I BELIEVE,
AS PART OF THIS CENTER,
PART OF NASA,
IS TO ADDRESS THOSE
TECHNICAL CHALLENGES.
SO, QUESTION--
WE HAVE DONE AMAZING THINGS.
WE BROUGHT BACK ASTRONAUTS
FROM THE MOON,
AND THAT WAS
ENTRY, DESCENT, LANDING.
YOU HAD TO COME THROUGH
THE PLANET EARTH ATMOSPHERE.
YOU HAD TO DESCEND,
SLOW DOWN,
AND THEN LAND SAFELY.
AND THEN WE BUILT SHUTTLE,
WHICH IS A LIFTING BODY,
LIKE AN AIRPLANE.
IT GENERATES LIFT.
AND WE FERRIED MILLIONS
OF POUNDS BACK AND FORTH
TO THE STATION WITH ASTRONAUTS
ON BOARD SAFELY.
SO WHAT'S THE CHALLENGE OF MARS?
WHY IS IT MARS?
SO I HAVE TWO GOOD FRIENDS
AND COLLEAGUES OF MINE
THAT ARE--THAT HAVE
EXPLAINED THIS CHALLENGE
OF WHY MARS IS SO DIFFICULT
IN THIS VIDEO.
- ONE OF THE GREATEST CHALLENGES
IS FIGURING OUT
HOW TO TAKE THE HUMANS
AND FLY THEM SAFELY
THROUGH THE ATMOSPHERE DOWN
TO THE SURFACE.
- THE AIR IS SO THIN ON MARS
THAT THE VEHICLES
DON'T SLOW DOWN
TO A POINT WHERE YOU CAN
SLIDE YOUR ENGINES
BELOW THE SPEED OF SOUND.
THAT'S A BIG PROBLEM,
AND HOW WE MIGHT SOLVE THAT
IS TO USE VERY LARGE,
POTENTIALLY
VERY LARGE HEAT SHIELDS
OR AEROSHELLS,
THINGS THAT ACTUALLY USE
THE AIR IT PUSHES ON
TO SLOW DOWN.
- WE'VE DONE THIS
FOR ROBOTIC MISSIONS,
BUT WE'VE DONE IT
AT A VERY SMALL SCALE.
AND IT'S VERY HARD
TO EXTRAPOLATE
THOSE TECHNICAL SOLUTIONS
TO THE LARGE SCALE
OF HUMAN EXPLORATION.
WELL, WE'RE BASICALLY TALKING
ABOUT LANDING
TWO-STORY HOUSES
ON THE SURFACE OF MARS,
ONE RIGHT NEXT TO EACH OTHER.
- THE OTHER CHALLENGE,
OF COURSE,
IS COMING BACK TO EARTH.
NOW YOU CAN IMAGINE
WE CAN PUT PEOPLE
IN A SPACE CAPSULE
AS THEY ARRIVE TO EARTH
AND DIRECTLY LAND ON EARTH
LIKE WE DO
COMING BACK FROM THE MOON.
WELL, THAT'S EXACTLY THE IDEA.
HOWEVER, YOU'RE COMING BACK
MUCH FASTER.
THE HEATING RATES
ARE MASSIVELY HIGH.
EVEN THOUGH THE VEHICLE IS
QUITE A BIT SMALLER
THAN LANDING ON MARS,
IT'S STILL A HUGE PROBLEM.
- AS YOU KNOW--MOST OF
YOU MAY KNOW
THAT AMES RESEARCH CENTER
SPECIALIZES
IN THERMAL PROTECTION SYSTEM.
WE INVENTED MOST
OF THE T.P.S. MATERIALS
THAT FLEW ON SHUTTLE.
"STARDUST" IS ANOTHER,
THE PICA MATERIAL.
AND THAT IS WHAT
HAS HELPED SPACEX
TO ACHIEVE
WHAT THEY HAVE SO FAR.
AND THOSE INVOLVEMENTS
ARE VERY WELL KNOWN.
BUT OUR INVOLVEMENT
IN ENTRY SYSTEM,
ENTIRE SYSTEM OF GETTING--
THAT'S NOT.
AND THAT'S GOING TO BE
A PART OF THIS TALK.
AS MENTIONED IN THESE,
THE CHALLENGE
OF MARS ENTRY, DESCENT,
LANDING IS PRIMARILY
BECAUSE THE ATMOSPHERE
OF MARS IS SO THIN.
SHOWN HERE IS THE ATMOSPHERIC
DENSITY PROFILE AS A FUNCTION
OF ALTITUDE, BUT THE DENSITY
IS PLOTTED IN LOG SCALE.
THE RED IS MARS'
ATMOSPHERIC DENSITY.
THE BLUE IS EARTH.
AND THEN VENUS IS IN THE
DARK BLACK DOTTED LINE.
YOU'LL SEE THAT THE MARS
DENSITY AT THE SURFACE OF MARS
COMPARED TO EARTH
IS 1% OF EARTH DENSITY.
SO THROUGHOUT ITS ATMOSPHERE
IF YOU'RE DESCENDING
WITH THE SAME SIZE VEHICLE,
YOU WON'T GET MUCH DRAG.
THAT MEANS YOU'RE
NOT SLOWING DOWN.
THAT MEANS MARS IS COMING
AT YOU VERY, VERY FAST.
SO WHAT DO WE DO ABOUT IT?
THAT'S THE CHALLENGE.
I'M GOING TO COME
BACK TO VENUS LATER ON.
VENUS'S SURFACE
DENSITY IS 100 BARS,
100 TIMES EARTH ATMOSPHERE.
AND THE SURFACE TEMPERATURE
IS 450 DEGREES OR HIGHER,
IN TERMS OF CENTIGRADE.
SO THE TWO PLANETS THAT ARE
SURROUNDING US HAVE SUCH
A VAST DIFFERENCE IN TERMS
OF ATMOSPHERIC COMPOSITION,
DENSITY, AND SO ON
AND SO FORTH.
THE CONCEPT I'M GOING TO
DESCRIBE LATER ON IN A FEW
MINUTES THAT ARE APPLICABLE
TO BOTH THESE PLANETS.
THAT'S THE BEAUTY OF
THIS CONCEPT AS WELL.
THE CHALLENGES FOR E.D.L.,
ENTRY, DESCENT, LANDING--
WE HAVE BEEN SUCCESSFUL.
THEY HELP US TO UNDERSTAND
WHAT DO WE DO NEXT
WHEN WE SCALE UP
TO HUMAN MISSIONS.
SO I'LL PLAY THOSE TWO ENTRY,
DESCENT, LANDING MOVIES.
ONE IS THE PATHFINDER,
THE SMALLEST ROVER.
IT'S A MICROROVER, 16 KG.
YOU KNOW, YOU CAN PICK IT UP
AND NOT NECESSARILY
PUT IT IN A BACKPACK, BUT IT'S
VERY BACKPACK-CARRYABLE SIZE.
THE OTHER ONE IS THE
MARS SCIENCE LABORATORY,
THE LANDER, THAT IS LIKE
A MINI COOPER,
ALMOST A METRIC TON.
THIS IS THE MARS PATHFINDER.
SO WHAT YOU SAW,
THE LANDING PART
WITH THE AIRBAG,
IF YOU PUT A HUMAN BEING
THERE AFTER NINE MONTHS
OF JOURNEY TO MARS, THAT WOULD
BE A PRETTY BIG CHALLENGE.
[audience laughs]
SO WE KNOW, IN TERMS OF MASS,
THIS PARTICULAR--
THIS IS AN EVENT DIAGRAM,
BASICALLY,
OF VARIOUS EVENTS THAT HAPPENED.
THAT'S THE ENTRY.
THAT'S HYPERSONIC.
AND WE ARE COMING
AT 17,000 MILES AN HOUR,
AROUND 150,000 FEET OR SO.
BETWEEN THAT AND THE PARACHUTE
OPENING HAPPENS IN TWO MINUTES.
WE'RE SLOWING DOWN
TO 1,000 MILES AN HOUR.
ALL OF THIS DONE WITH
THAT AEROSHELL, ESSENTIALLY,
2.65 METER DIAMETER
AEROSHELL.
THEN IN THE NEXT TWO MINUTES,
WE HAVE DONE ALL OF THESE
MANEUVERS AND LANDED,
ESSENTIALLY.
THE MICROROVER
WAS 16 KILOGRAMS,
AND THIS IS THE SPACECRAFT.
THE SPACECRAFT AT THIS POINT
WAS 890 KILOGRAMS, ESSENTIALLY.
I'M SORRY.
SPACECRAFT RIGHT HERE.
THIS IS 570 KILOGRAMS.
SO IN THE NEXT--I'M GOING TO
SHOW MARS SCIENCE LABORATORY.
I'LL SHOW YOU WHAT
THE TAKE-OFF MASS FOR MARS
SCIENCE LABORATORY
WAS FOR 1 METRIC TON.
THEN YOU'LL APPRECIATE WHY
A HUMAN MISSION
MAY HAVE TO INVENT NEW WAYS
OF GETTING TO MARS.
YOU SAW THIS AIRBAG TECHNIQUE
WOULD NOT WORK
FOR MARS SCIENCE LABORATORY.
AND SO, JPL REALLY HAD
TO COME UP WITH SOME VERY
CREATIVE WAYS
OF HOW DO WE LAND.
AND JUST LIKE THAT SLOGAN,
"YOUR THIGH BONE IS CONNECTED
TO THE HIP BONE," THE LANDING
ALL THE WAY TO ENTRY--
NOT ONLY THAT,
THE TAKE-OFF FROM EARTH,
THEY'RE ALL INTERCONNECTED.
YOU HAD TO PLAN EVERY ONE
OF THOSE THINGS TOGETHER
IN A SEQUENCE BECAUSE ONCE
YOU ENTER MARS SURFACE,
YOU HAVE NO CONTROL OVER
ANYTHING FOR THE PATHFINDER.
NOW, MARS SCIENCE LABORATORY
IS SLIGHTLY DIFFERENT,
AND IT HAS GREATER CONTROL,
BUT IT'S AUTONOMOUS.
WE DON'T--
WE CAN'T CONTROL IT.
SO YOU'LL SEE THAT
IN A MINUTE.
IMAGINE MARS
AS A VERY DOT IN THE SKY.
WHEN YOU LEAVE EARTH, YOU
HAVE TO POINT YOUR SPACECRAFT
VERY PRECISELY.
THE PRECISION,
IF YOU HAVE ANY ERROR,
THEN YOU'RE CARRYING A LOT
OF FUEL TO CORRECT THAT.
AND WE ARE THE ONLY NATION
TO BE ABLE TO LAND THINGS
ON MARS TO DATE.
WE HAVE PERFECTED THAT ART
AND THE ENGINEERING BEHIND IT.
SO WE JUST LEFT PLANET EARTH.
AND THAT JOURNEY
IS A LONELY 7 1/2--
8 1/2 MONTHS FOR M.S.L.
IT'S IN DEEP SPACE.
IT'S ALL SILENT.
YOU DON'T HEAR ANYTHING
IN SPACE.
YOU SEE THOSE
WEIGHTS DROPPING?
THOSE ARE DEAD WEIGHTS.
THEY'RE DROPPED TO GET
LIFT VECTOR ESSENTIALLY,
SO THAT THE CENTER OF GRAVITY
IS A LITTLE OFFSET.
AND YOU SEE THAT THE ACTION
CONTROL JETS ARE FIRING
TO ORIENT THE LIFT VECTOR.
IF YOU WANT TO
GO LEFT OR RIGHT,
ALL OF THAT IS CALLED GUIDANCE,
NAVIGATION, AND CONTROL.
IN APOLLO, WE DID THAT.
AND WE ARE DOING IT
AGAIN FOR M.S.L.
ALL THOSE SOUNDS YOU HEARD,
WE'RE DROPPING MORE DEAD WEIGHTS
TO ALIGN ITSELF SO THE PARACHUTE
CAN BE DEPLOYED.
THE ENTIRE SYSTEM IS DROPPED,
THE LANDER IS DROPPED
ON ESSENTIALLY
A LITTLE ROCKET.
IT HAS TO COME DOWN TO
A VERY STEADY STANDSTILL...
LIKE A HUMMINGBIRD,
ESSENTIALLY.
AND THEN IT'S GOING TO DROP
THE ROVER DOWN.
AND ALL OF THIS
IS DONE AUTONOMOUSLY
WITH ALL THE THINGS THAT COULD
GO WRONG TAKEN INTO ACCOUNT.
AND FINALLY,
THAT LAST MANEUVER,
THEY HAD TO TAKE THE
RETROPROPULSION SYSTEM AWAY
SO THAT IT DOESN'T LAND
ON TOP OF THE ROVER.
SO THE TIMELINE,
IF YOU LOOK AT--
WE ARE ENTERING MARS
VERY SIMILAR--IT'S A LITTLE
LESSER SPEED, ENTRY SPEED.
BUT THE AEROSHELL WAS
4 1/2 METER DIAMETER
AND VERY SIMILAR
TO THE PATHFINDER AEROSHELL.
BUT THE THING THAT HAPPENED
HERE WAS THAT DURING
THE HYPERSONIC PART, WE DID
A HYPERSONIC AEROMANEUVERING
BY TILTING THE GEOMETRY
IN A WAY BY C.G. OFFSET
SO IT'LL GENERATE
LIFT VECTOR.
IF YOU GENERATE LIFT
VECTOR LIKE AN AIRPLANE,
IN A WAY, YOU ARE TAKING
ADVANTAGE OF THE LIFT TO KEEP
THE AIRPLANE IN AIR
FOR A LONGER TIME.
LONGER TIME MEANS THAT MARS
IS NOT COMING AT YOU AS FAST.
YOU CAN DECELERATE.
AND WE WERE--THE LANDED ROVER
IS 900 KILOGRAMS.
AND THE LAUNCH MASS FOR THIS
IS 1/2 MILLION KILOGRAMS.
SO IMAGINE THE SCALE IF YOU
WANT TO DO HUMAN MISSIONS.
THEY WILL BE SOMEWHERE
BETWEEN 20 METRIC TONS
TO 40 METRIC TONS,
SOMEWHERE IN THAT BALLPARK.
NOT ONE METRIC TON.
THAT'S WHAT YOU HAVE TO LAND,
AND YOU CAN WORK BACKWARDS
TO START TO SEE THAT SOME
OF THEM ARE IMPOSSIBLE TODAY
WITH THE CURRENT TECHNOLOGY,
EVEN TO LIFT OFF
FROM THE GROUND.
THAT'S WHY WE ARE BUILDING
S.L.S. LAUNCH SYSTEMS,
THE HEAVY LIFT VEHICLES
AND SO ON THAT ONE DAY
WILL ALLOW US TO THROW THINGS
AT MARS
THAT ARE NEEDED
FOR HUMAN PRESENCE.
SO GETTING TO THE SURFACE
OF MARS REQUIRES
SOME SIGNIFICANT CHALLENGES.
WE SAW BETWEEN PATHFINDER
AND M.S.L.
HOW THINGS WERE VERY DIFFERENT.
THE LARGEST ROCKET TODAY
WE HAVE IS 5 METER DIAMETER.
THAT'S THE SIZE
THAT WE CAN LAUNCH.
SO MARS BEING SO RAREFIED
IN TERMS OF THE DENSITY,
HOW DO WE LAND
40 METRIC TONS?
GETTING BACK TO EARTH
IS ANOTHER THING.
AMES IS WORKING ON BOTH.
AND I'M LUCKY ENOUGH
TO BE WORKING WITH PEOPLE
THAT ARE HERE.
AND TOWARDS THE END,
I'LL ASK THEM TO STAND UP.
AND THEY ARE DOING ON BOTH
OF THESE ASPECTS.
GOING TO MARS WILL NOT
BE A SINGLE MISSION.
IT'LL BE A WHOLE CAMPAIGN.
WE HAVE TO HAVE RESOURCES
AT THE SURFACE.
AND THEN ONCE
HUMANS GET THERE,
THE ALIGNMENT OF EARTH AND MARS
HAS TO HAPPEN IN SUCH A WAY
THAT WE CAN GET THEM BACK
IN THE SHORTEST PERIOD OF TIME
OR WITH THE SHORTEST
AMOUNT OF ENERGY.
BECAUSE WE HAVE TO LEAVE
THE GRAVITY WELL OF MARS
TO COME BACK.
SO THESE THINGS
WOULD BE OVER A DECADE.
SO WE HAVE TO THINK,
IN TERMS OF TECHNOLOGY,
HOW ARE THESE TECHNOLOGIES GOING
TO BE UTILIZED
IN MULTIPLE MISSIONS?
SOME ARE CARRYING CARGO.
SOME ARE CARRYING CREW.
AND ALSO THE MASS THAT WE WILL
DELIVER AT THE SURFACE
OF MARS COULD BE SCALABLE,
IN THE SENSE YOU MAY BE DOING
SOME AT 10 METRIC TONS,
OTHERS, 40 METRIC TONS,
DEPENDING ON WHAT
ARCHITECTURE IS.
WE HAVEN'T YET DECIDED
HOW WE ARE GOING TO DO ALL THAT.
SO ANY TECHNOLOGY
WE INVENT TODAY,
IT HAS TO HAVE CERTAIN
CHARACTERISTICS.
NOT A REQUIREMENT BECAUSE
WE DON'T KNOW WHAT EXACTLY
MARS MISSIONS ARE GOING
TO LOOK LIKE.
SO I CALL THEM DESIREMENTS.
IT HAS TO BE MASS EFFICIENT.
I ALREADY SHOWED YOU WHY.
IT HAS TO HAVE A VERY LARGE
DRAG SURFACE BECAUSE MARS
DEMANDS VERY LARGE
DRAG SURFACE.
PINPOINT LANDING--IF YOU'RE
GOING TO HAVE A SET OF THINGS
AT MARS FOR HUMANS
TO UTILIZE RESOURCES,
YOU HAVE TO LAND
RIGHT NEXT TO IT
BETTER THAN M.S.L. LANDED.
THAT'S A BIG, TALL ORDER.
AND THEN OPERATIONAL
CONSIDERATIONS.
THERE'S A MANEUVER
CALLED AEROCAPTURE.
YOU DIDN'T SEE THAT.
I'M GOING TO SPEND A MINUTE
OR SO IN THE NEXT SLIDE.
AND THEN TRANSITIONS.
YOU SAW HOW AN AEROSHELL
HEAT SHIELD HAS TO BE DEPLOYED.
AND THEN YOU HAD TO TRANSITION
FROM HYPERSONIC
TO A SUPERSONIC PHASE
WITH A PARACHUTE,
AND THEN TO A LANDING PHASE.
THOSE TRANSITIONS ARE ALL
BIG CHALLENGES
WHEN YOU ESPECIALLY THINK ABOUT
VERY LARGE DIAMETER OBJECTS,
BASICALLY, AND HEAVY MASSES.
AND THEN RISK.
EVEN THOUGH I THINK OUR
CENTER DIRECTOR HAS SIGNED UP
TO GO TO MARS ONE-WAY TRIP,
I DON'T THINK TOO MANY OF US
WOULD AGREE FOR HIM TO GO.
MAYBE SOME--SOME MAY.
[audience laughs]
BUT THE WHOLE POINT IS,
WE AS A NATION,
I DON'T THINK WE WOULD VENTURE
INTO NOT BRINGING BACK
OUR ASTRONAUTS,
ESPECIALLY THE ONES
THAT TOUCH THE SURFACE OF MARS
THE FIRST TIME.
SO RETURNING IS ALSO
A BIG CHALLENGE.
RISK POSTURE FOR THOSE MISSIONS
IS A BIG CHALLENGE.
WE CAN'T AFFORD TO GO--
SOMETHING TO GO WRONG.
SO HOW DO YOU DESIGN
A VERY COMPLEX SET OF MISSIONS
YOU HAVE TO CHOREOGRAPH?
EXPENSIVE.
SO THOSE ARE ALL CONSIDERATIONS
WE HAVE TO THINK ABOUT.
AND THEN FINALLY,
SCALABILITY.
AEROCAPTURE IS NOT
VERY DIFFERENT.
IT'S SIMILAR TO ENTRY,
HYPERSONIC ENTRY.
WHEN WE CALL AEROCAPTURE,
THAT MEANS INSTEAD OF DOING
PROPULSIVE REDUCTION
AND VELOCITY,
WE USE THE ATMOSPHERE
TO SLOW DOWN.
BUT WE DON'T GO AND LAND.
BUT WE COME OUT AFTER WE LOSE
A CERTAIN AMOUNT
OF KINETIC ENERGY, AND THEN PUT
THIS WHOLE SPACESHIP
AROUND THE ORBIT OF MARS.
WHY DO WE WANT TO DO THAT
FOR HUMAN MARS MISSION?
BECAUSE WE WANT
TO HAVE ASTRONAUTS, OUR ASSETS,
IN THE SKY AS THE CREW
ON THE GROUND IS WORKING AWAY
IF THERE IS A REASON
FOR COMMUNICATION
OR FOR RISK POSTURE TO GET BACK
OUT OF THE MARS SURFACE SAFELY.
SO IT IS PART OF THE DESIGN
WE HAVE TO THINK ABOUT.
ANOTHER THING--
HOW GOOD DO WE KNOW
WHEN WE DESIGN THESE SYSTEMS?
THE HYPERSONIC AEROPHYSICS,
THE PHYSICS-BASED,
OUR ABILITY TO SIMULATE,
IS BASED ON OUR ABILITY TO TEST.
WE HAVE SOME GREAT FACILITIES
THAT ARE AVAILABLE TO US
TO UNDERSTAND THE PHYSICS.
AND ALSO, WE GET FLIGHT DATA.
ALL OF THOSE
THINGS ARE HELPING.
THE CHART THERE,
I'M NOT GOING TO GO INTO IT.
THAT'S PROBABLY FOR PEOPLE
TO UNDERSTAND THAT IT'S
A GOOD GRADUATE SCHOOL
SERIES OF LECTURES.
BUT IT KIND OF TELLS YOU
WHEN YOU HAVE TO SLOW DOWN
FROM 17,000, 20,000 MILES
AN HOUR IN 2 MINUTES
TO ALMOST 0,
LOTS OF THINGS HAPPEN.
HYPERSONICALLY, SHOCK LAYER,
THINGS RADIATE, THINGS HEAT UP.
YOU HAVE TO CARE
FOR ALL OF THOSE THINGS.
WE HAVE THOSE TOOLS
THAT WE HAVE A CERTAIN AMOUNT
OF CONFIDENCE IN THEM.
WE HAVE PREDICTED THE ENTRY
OF THE MARS SCIENCE LABORATORY.
WE INSTRUMENTED IT.
WE DID VERY WELL.
SO THOSE THINGS GIVE US
CONFIDENCE WHEN YOU GO
TO A LARGER AND LARGER SCALE.
NOW, WITH THAT,
I'LL TELL YOU,
THERE ARE WAYS IN WHICH
WE CAN GET TO MARS AND WHY SOME
OF THEM ARE IMPOSSIBLE
AND OTHERS MAY BE POSSIBLE.
NASA, IN 2010,
COMPLETED A STUDY.
THE STUDY WAS DONE
A YEAR AND A HALF OR SO.
AND THE STUDY LOOKED AT
WHAT WOULD IT TAKE TO LAND
40 METRIC TON
AT THE SURFACE OF MARS.
THE PHASES, DIFFERENT PHASES,
ARE SHOWN HERE.
THIS IS THE AEROCAPTURE,
HYPERSONIC,
SUPERSONIC, SUBSONIC,
AND THEN LANDED PHASE.
YOU CAN DO THE ENTIRE
THING WITH RETROPROPULSION.
IF YOU THINK YOU CAN DO IT,
WHAT WOULD BE THE AMOUNT
OF FUEL YOU WOULD NEED
TO SLOW DOWN
AND GET TO THE SURFACE
OF MARS?
AND THAT'S
WHAT IS THE VERY FIRST--
THIS ARCHITECTURE.
IF YOU ARE DOING
EVERYTHING PROPULSIVELY,
SLOWING DOWN, THAT WILL REQUIRE
265 METRIC TONS
WHEN YOU ENTER THE SURFACE.
THAT'S THE AMOUNT OF FUEL,
ESSENTIALLY,
YOU'RE CARRYING IN THE ENGINE
FOR SLOWING DOWN.
THAT'S IMPOSSIBLE
FOR US TO THEN LIFT
THAT MUCH MASS AND THROW IT
AT A VELOCITY ESCAPING
THE GRAVITY WELL OF EARTH
TOWARDS MARS AND DOING ALL THAT.
SO THE NEXT SCENARIO IS,
WHY DON'T WE USE SOMETHING
LIKE SHUTTLE?
YOU NEED A LARGE SURFACE.
YOU NEED A LIFT FOR GUIDING,
PRECISION CONTROL, FLIGHT.
SO WE DON'T HAVE
A KENNEDY SPACE CENTER ON MARS
SO YOU CAN LAND
SHUTTLE-LIKE OBJECTS.
BUT YOU CAN USE IT
FOR AEROCAPTURE.
YOU CAN USE IT
FOR HYPERSONIC.
THEN YOU NEED TO TRANSITION
OUT OF THAT
INTO A RETROPROPULSION MODE,
ESSENTIALLY.
SO THAT'S WHAT THIS
MIDDLE COLUMN IS.
THIS GUY.
SO SOMEWHERE AROUND
SUPERSONICALLY,
YOU TRANSITION INTO
RETRO AND GO LAND.
THAT'S AROUND
110 METRIC TONS.
THIS TECHNOLOGY WE KNOW HOW
TO DO BECAUSE WE HAVE BEEN
FLYING SHUTTLE
FOR ALL THESE 30 YEARS OR SO,
AND THAT'S DOABLE.
BUT IS THERE ANY BETTER SYSTEM?
SO THERE ARE, AND THE ONE
THAT THIS PARTICULAR STUDY
LOOKED AT IS CALLED
"INFLATABLE."
AND THE INFLATABLES
ESSENTIALLY--THE RUSSIANS
TRIED TO DOUBLE UP
INFLATABLE TECHNOLOGY.
AND THEN WE HAVE BEEN LOOKING
AT IT FOR MANY YEARS NOW.
AND THERE'S GOING TO BE
A TEST IN HAWAII
THAT WAS SUPPOSED TO HAPPEN LAST
WEEK CALLED L.D.S.D.,
AND IT'S A SUPERSONIC
DEPLOYABLE.
AND THAT DIDN'T HAPPEN.
IT'LL HAPPEN VERY SOON.
IT'S THE SAME THING.
YOU HYPERSONICALLY
INFLATE SOMETHING,
A BIG BALLOON ESSENTIALLY.
AND THAT GIVES YOU DRAG
DURING AEROCAPTURE.
YOU CAN'T REUSE IT, SO YOU
USE ANOTHER INFLATED DEVICE
FOR HYPERSONIC.
AND THEN SUPERSONICALLY,
YOU NEED MUCH LARGER SURFACE
WHEN YOU DO THAT.
SO IT'S A SERIES
OF INFLATION DEVICES.
THAT MAY GET US 81 METRIC TONS.
SORRY ABOUT THIS.
NOW I COME TO THE CONCEPT
THAT WE HAVE BEEN WORKING
SINCE 2011 OR SO,
WE STARTED OUT.
IT'S A VERY SIMPLE CONCEPT
FOR ONE TO THINK ABOUT.
ALL THE LAUNCH SYSTEMS HAVE
A LIMITATION OF HOW LARGE
A SHAPE THAT YOU CAN LAUNCH.
SO IF YOU CAN THINK OF IT,
THIS SITS IN A SHROUD.
THAT'S WHAT
THE STOWED CONFIGURATION IS.
AND THEN,
AFTER YOU'VE LEFT EARTH,
EITHER BEFORE DEPARTURE
TOWARDS THE PLANET
OR WHEN YOU COME
TO THE SURFACE OF THE PLANET,
CLOSE TO IT,
YOU CAN DEPLOY IT.
IT IS SIMPLY
AN UMBRELLA CONCEPT.
SO AN UMBRELLA PROTECTS US FROM
RAIN AND SUN AND ALL OF THAT.
THIS WILL ALLOW US
TO GENERATE DRAG.
AND ALSO, THE SKIN,
WHICH IS VERY SPECIALIZED--
I WILL TALK ABOUT IT
IN A MINUTE--
THAT ALSO PROTECTS THE REST
OF THE PAYLOAD FROM THE HEATING.
BECAUSE THE UMBRELLA IS OPEN
TO THE BACK AND THE FRONT,
A LOT OF THAT HEATING
IS RADIATED INTO SPACE.
THAT'S ANOTHER ADVANTAGE
OF THIS.
IT'S A VERY SIMPLE CONCEPT,
BUT WHEN YOU THINK ABOUT
23-METER DIAMETER OR 15-METER
DIAMETER AND THE AMOUNT
OF LOAD YOU HAVE TO WITHSTAND
AT VERY HIGH TEMPERATURES,
THEY BECOME VERY CHALLENGING
TO SOLVE THOSE PROBLEMS.
NOW THE SAME UMBRELLA,
WHAT I SHOWED EARLIER,
WAS A BALLISTIC ENTRY CONCEPT,
WHICH MEANS THAT YOU DEPLOY IT
AND YOU HOLD THE SHAPE,
IT CAN ENTER.
THIS IS LIKE PATHFINDER.
THEY DIDN'T DO
ANY MANEUVERING.
THE SAME CONCEPT
WHEN YOU DEPLOY IT.
THIS IS A VERY SIMPLIFIED MODEL.
YOU CAN MOVE THE FRONT SURFACE
WITH RESPECT TO A PAYLOAD.
THAT MEANS IF I WANT
TO GO LEFT OR RIGHT,
I CAN DO THAT
BY SIMPLY LEVERAGING THAT.
IT'S LIKE SAILBOATS,
ESSENTIALLY, HOW WE DO.
AND THAT'S HOW WE GET
LIFT MANEUVERING PART.
AND THEN THERE'S ANOTHER
INVENTION, PARTLY--
IS YOU THINK ABOUT UMBRELLA
FLIPPING IN THE WIND.
IF YOU DO A CONTROLLED FLIP,
YOU CAN USE THOSE
BEEFY STRUCTURES THAT WE HAVE
TO WITHSTAND THE ENTRY LOAD.
THEY CAN BE USED FOR LANDING.
SO YOU DON'T GET RID
OF THE UMBRELLA.
YOU MAKE USE OF THE UMBRELLA,
ESSENTIALLY, SURFACE.
SO THIS MOVIE
IS GOING TO SHOW YOU...
WHAT I TALKED ABOUT.
DEPLOYMENT.
MANEUVERING.
SO WE CAN DO THIS DESIGN,
AND WE HAVE BUILT MODELS.
AND I'M GOING TO HURRY UP.
I DON'T HAVE MUCH TIME LEFT.
AND MY APOLOGIES.
BUT WE HAVE BUILT A SERIES
OF MODELS HERE.
LATER ON, YOU CAN COME
AND LOOK AT THEM.
AND AN INDEPENDENT STUDY WAS
DONE LAST YEAR AT THE REQUEST
OF THE S.D.M.D. DIRECTOR,
ASSOCIATE ADMINISTRATOR.
AND THAT STUDY
LOOKED AT OUR CONCEPT,
AND THEY CONFIRMED
THAT THE CONCEPT IS VERY VIABLE
AND THE CHALLENGE REALLY IS
WE DON'T KNOW HOW ALL
OF THESE CONCEPTS ARE GOING
TO FIT INTO THIS ARCHITECTURE.
SO WE NEED TO GET
SOME REFINEMENT.
AND ALSO, WE NEED TO DIAL UP
THESE ARCHITECTURES.
BEFORE WE BUILD
23-METER DIAMETER,
WE HAVE TO BE BUILDING
SMALLER SCALE.
THAT WAS THE FINDING.
SO WE GET TO MARS
SOMEWHERE BEYOND 2035.
IT'S NOT CLEAR WHETHER THAT'S
A REALISTIC TIME PERIOD OR NOT.
BUT WE NEED TO BE WORKING ON
THE TECHNOLOGY DEVELOPMENT NOW.
AND IN A FEW YEARS,
A DECADE FROM NOW OR SO,
STATION WILL--ITS LIFE
EXPECTANCY IS NOT LAST.
SO FOR US, DOING THE TECHNOLOGY
DEVELOPMENT RIGHT NOW
IS A VERY IMPORTANT ASPECT
THAT NASA IS STRESSING.
SO WHEN WE LOOK AT--
BEFORE WE BUILD A 23-METER,
WHERE ELSE COULD
THIS CONCEPT BE USED?
VENUS IS A PLACE.
WE HAVE DONE VENUS
MANY TIMES BEFORE.
THE RUSSIANS HAVE,
AND WE HAVE PLANNED A VENUS.
BUT ENTRY INTO VENUS, BECAUSE
OF ITS ATMOSPHERE, AGAIN,
AND THE KIND OF TECHNOLOGY
WE HAVE,
IT REQUIRES--DURING ENTRY,
THE PROBE WILL ENCOUNTER
SOMETHING LIKE 200 TO 650 G,
DEPENDING ON HOW MASSIVE IT IS,
HOW HEAVY IT IS.
SO THIS CONCEPT CAN HELP.
AND WE HAVE BEEN LOOKING AT
THIS CONCEPT VERY SERIOUSLY
FOR THE LAST YEAR AND A HALF
OR SO.
AND THAT'S A CONCEPT
FOR VENUS.
AND THIS IS A MOVIE THAT SHOWS
THE VENUS CONCEPT.
SPACE TECHNOLOGY MISSION
DIRECTORATE MADE THIS MOVIE
FOR PUBLIC RELEASE.
[electronic music]
SO THAT'S ONLY
6-METER DIAMETER.
IT CAN LAND 1,000 KILOGRAMS.
[electronic music]
SO NOW THE HEAT SHIELD
IS DEPLOYED.
THE PAYLOAD IS NOW GOING
TOWARDS THE SURFACE OF VENUS
ON PARACHUTE FOR A WHILE
AND THEN JUST DROPPING.
THE SURFACE OF VENUS IS VERY
THICK AND GOOEY, SO TO SAY.
SO THE LOAD THAT THIS
CONFIGURATION WILL EXPERIENCE
REQUIRES SOME COMPLEX
MECHANICAL SYSTEM.
YOU HAVE TO DEPLOY AND YOU HAVE
TO HOLD THE FABRIC IN TENSION
AND ALL OF THAT.
AND THE "ADEPT" WORD IS
"ADAPTIVE DEPLOYABLE ENTRY
AND PLACEMENT TECHNOLOGY."
THAT'S WHAT ITS ACRONYM
STANDS FOR.
AND THIS IS A CARBON FABRIC.
I HAVE A SAMPLE HERE.
AND IF YOU WANT TO COME LATER,
YOU CAN TAKE A LOOK AT THEM.
AND THAT HAS UNDERGONE
AN EXTENSIVE TESTING.
SO 20 TIMES LOWER ENTRY
HEATING MEANS WE CAN TEST
THESE MATERIALS IN THE FACILITY
THAT'S AVAILABLE TODAY.
WE DON'T HAVE TO BUILD
A NEW FACILITY.
AND DRAG REDUCTION
ORDER OF MAGNITUDES.
THAT MEANS THAT YOU CAN USE
SCIENTIFIC INSTRUMENTS
THAT WE ARE USING TODAY
IN M.S.L. TO INVESTIGATE VENUS.
YOU DON'T HAVE
TO STANDARDIZE THEM
OR DO ANYTHING TO WITHSTAND
THOSE ENTRY LOADS.
SO WE START
WITH THIS CONCEPT STUDY.
WE BUILT A GROUND TEST ARTICLE.
AND I'LL SHOW ONE QUICK MOVIE.
THIS ARTICLE IS AVAILABLE,
IF YOU'RE INTERESTED
TO SEE THIS IN--
IT'S FUNCTIONING.
IT'S A VERY SIMPLE CONCEPT.
BUT YOU CAN SEE SOME OF MY
COLLEAGUES SITTING HERE.
LATER ON, I'LL ASK THEM
TO STAND UP.
THEY ARE DOING THE TESTING.
AND IT'S PAINTED WHITE
SO THAT WE CAN SEE
HOW THE FABRIC MOVES
DURING LOADING.
AND THEN WE DID ARC-JET TESTING
OF THE CARBON FABRIC.
THE CARBON FABRIC IS THE KEY
TO THE SUCCESS OF THIS CONCEPT.
AND I'M GOING TO RUN THIS
LITTLE--THAT'S AN ARTICLE
WHERE WE LOAD UP THE FABRIC
MECHANICALLY ON--
CALLED BIDIRECTIONAL,
BOTH DIRECTIONS.
AND THAT'S A MODEL.
AND WE HAVE TESTED THIS.
OOPS, SORRY.
LET ME--
AND WHAT YOU'LL SEE IN THIS
MOVIE, YOU SAW A BIT OF IT.
THE ARC JET IS A PLACE WHERE
WE CAN GENERATE
THE SAME HEAT--HOT ENVIRONMENT
OF AIR FLOWING OVER MODELS.
THAT'S A MODEL,
WEDGE MODEL.
AND THE SURFACE OF THE FABRIC--
IT'S A WOVEN FABRIC,
THREE-DIMENSIONALLY WOVEN
TO TAKE ALL THE HEAT
AND ALSO THE LOADS
AT THE TEMPERATURE.
AND YOU CAN SEE LITTLE SPOTS
GOING AWAY.
THIS TEST WENT UP TO
220 SECONDS OR SO.
AND THE CONDITION AT
WHICH THIS WAS TESTED,
FAR GREATER THAN WE WOULD
EVER NEED FOR MARS,
HUMAN MARS MISSIONS.
AND IT'S MORE
VENUS-RELEVANT CONDITION.
AND THE SUCCESS OF THIS TEST
COMBINED WITH THE ENTIRE SYSTEM
BEING MECHANICAL,
THAT'S WHAT MAKES OUR CONCEPT
VERY ATTRACTIVE TO A LOT MORE
THAN JUST HUMAN MARS MISSIONS.
CURRENTLY, WE ARE LOOKING
AT A NANO-ADEPT.
NANO REPRESENTS
A VERY SMALL ADEPT.
THIS IS THE SIZE.
THIS IS A FULL-SCALE MODEL.
AND IT CAN TAKE 2 CUBE SATS
INSIDE, ESSENTIALLY,
WE CAN BRING BACK.
OR WE CAN PUT SCIENCE SAMPLES
INTO MARS'
OR VENUS' ENVIRONMENT.
SO THIS IS WHAT WE ARE
CURRENTLY WORKING ON.
AND WE'RE GOING TO BE DOING
A FLIGHT TEST IN YEAR 15.
AND IF YOU LOOK
AT WHAT WE HAVE DONE,
WE HAVE GONE FROM
SUB-1-METER SCALE, A 2-FOOT,
ALL THE WAY TO 23 METERS,
25 METERS CONCEPTUALLY.
THEY ARE VERY, VERY SIMILAR
ARCHITECTURALLY.
THE PIECES ARE THE SAME.
THE PHYSICS IS THE SAME.
AND SO, BY TESTING AT MUCH
SMALLER SCALE AND APPLYING IT,
WE ARE GOING TO LEARN
A LOT AND MOVE FORWARD.
SO IN TERMS OF SUMMARY, MARS IS
BOTH EXCITING AND CHALLENGING,
ESPECIALLY FOR HUMANS,
IF YOU WANT TO DO THAT.
WE HAVE COME TO THE END
OF THE ENTRY, DESCENT, LANDING
TECHNOLOGY THAT TODAY WE HAVE.
AND SOME OF THE TECHNOLOGY
INVESTMENT HAPPENING TODAY
IN THIS CONCEPT AS WELL
AS THE INFLATABLE,
THEY'RE GOING TO ALLOW US
TO GO TO MARS SOMEDAY SOON.
AND THE MECHANICALLY DEPLOYABLE,
SPECIFICALLY HAS
THE SCALABILITY,
THE RUGGEDNESS THAT WE NEED,
AND ALL OF THOSE DESIREMENTS
I TALKED ABOUT.
THAT'S HOW
IT'S KEPT IN MIND.
WE HAVE BEEN DESIGNING
AND WORKING ON THAT.
WITH THAT, I THANK YOU
VERY MUCH FOR YOUR TIME
AND LISTENING TO ME.
AND I'M READY TO ANSWER
ANY QUESTIONS.
[audience applause]
- SO PLEASE RAISE YOUR HAND
IF YOU HAVE ANY QUESTIONS.
- WELL, THIS IS FASCINATING.
THE THOUGHT THAT OCCURS TO ME
IS YOU'RE MAKING
THIS CARBON FIBER FABRIC.
IT'S NOT WHETHER IT WILL
WITHSTAND ATMOSPHERIC PASSAGE
BUT WHETHER IT WILL STAND
BEING FOLDED UP AND OPENED.
IF YOU FOLD IT UP AND THEN
MOVE IT TO MARS FOR 11 MONTHS,
WILL THE CONDITIONS
THAT IT SUFFERS--
WILL IT FALL APART
WHEN YOU OPEN IT?
- VERY GOOD QUESTION.
THE GROUND TEST ARTICLE THAT
I SHOWED IN THAT ONE PICTURE,
WE HAVE DONE
THE DEPLOYMENT AND FOLDING
AND UNFOLDING OF IT
A MULTITUDE OF TIMES.
BRIAN, 70, 80 TIMES?
YEAH, SOMETHING LIKE THAT.
WE CAN DO THAT
WITH NO SEEABLE DAMAGE AT ALL.
BUT IN SPACE, YOU'RE GOING
TO ONLY OPEN IT ONCE.
AND WE NEVER CLOSE THEM
AND OPEN THEM.
SO WE FOLD IT,
LAUNCH IT, AND OPEN IT.
AND IT'S HELD IN TENSION.
- IT'S THOSE CONDITIONS
DURING THOSE 8 MONTHS.
YOU'VE GOT...
- IT IS COLD, YES.
- TEMPERATURE, RADIATION.
- YEAH, CARBON FIBER
AND COLD TEMPERATURES
AND HOT TEMPERATURES.
CARBON SEEMS TO BE MUCH MORE
STABLE THAN ANY OTHER MATERIAL,
BUT WE HAVEN'T DONE
THE TESTING YET.
BUT WE WILL BE, DEFINITELY.
WE USE CARBON IN A LOT
OF OUR T.P.S. MATERIALS
AS A BASIS FOR.
WHAT WE KNOW, CARBON SHOULD NOT
HAVE A PROBLEM.
BUT WE HAVE NEVER,
EVER USED A WOVEN FABRIC
IN THIS FORM EVER BEFORE.
AND THAT IS SOMETHING
THAT WE'LL BE DOING.
- THERE'S ONE, BACK UP THERE.
- FASCINATING STUFF.
SO I PRESUME THE ARC JETS
WERE SET TO TEST
THE MARS PEAK HEATING PORTIONS
OF THE TRAJECTORY.
WHAT ABOUT WHEN THE HEATING
IS LESS,
BUT THE DRAG AND BUFFETING
ARE STRONG?
HOW DOES IT HOLD--
WHERE IS THAT IN THE TRAJECTORY,
AND HOW IS IT GOING TO WORK?
HAVE YOU TRIED THAT?
OTHER WIND TUNNELS AND STUFF?
- RIGHT.
GREAT QUESTION, AGAIN.
ANY TIME YOU DEPLOY SOMETHING,
IF IT'S NOT A RIGID AEROSHELL,
YOU CAN IMAGINE BUFFETING,
INFLATABLES AND DEPLOYABLES.
SO WHAT WE DO IS
WE TENSION UP THE FABRIC.
WE PUT LOAD INTO THE FABRIC.
AND IF YOU DO HAVE TIME,
LET ME KNOW,
AND PAUL WERCINSKI,
WHO IS THE PROJECT MANAGER
SITTING SOMEWHERE HERE,
WILL ARRANGE FOR PEOPLE
TO COME AND VISIT.
ONCE YOU LOAD UP THE FABRIC,
IT GETS TO BE AS RIGID
AS A RIGID AEROSHELL.
CARBON IS A WONDERFUL MATERIAL.
IT DOESN'T STRAIN MUCH.
IT'S A VERY TOUGH MATERIAL.
YOU CAN PUT SOME LOAD.
THAT'S THE VERY DESIGN.
AND ALSO, HYPERSONICALLY,
OPEN CONFIGURATIONS LIKE THIS,
THEY SEEM TO BE MORE STABLE.
WE DID--THERE WAS A FLIGHT TEST
THAT WAS DONE
FOR THE HYPERSONIC INFLATABLE
PROJECT CALLED IRVE,
AND IT CAME THROUGH THE
HYPERSONIC/SUPERSONIC/SUBSONIC
REGIMES WITH NONE
OF THE PROBLEMS, REALLY.
AND THIS IS A MUCH MORE
TENSIONED SYSTEM
COMPARED TO THE INFLATABLES
AS WELL.
SO WE DON'T EXPECT ANYTHING,
BUT WE'LL BE DOING SOME TESTING
IN THE BIG WIND TUNNELS
THIS YEAR AND NEXT YEAR
TO UNDERSTAND.
AND THE SOUNDING ROCKET
FLIGHT TEST I BRIEFLY FLASHED,
THAT IS ANOTHER PROOF
OF THOSE QUESTIONS
WE CAN RETIRE VERY EASILY.
MAKE SENSE?
OKAY.
- HI.
HAVE YOU THOUGHT ABOUT USING
THIS SYSTEM IN CONJUNCTION
WITH AN INFLATABLE DRAG SYSTEM
FOR ENTRY?
- YEAH.
GOOD QUESTION.
THE CARBON FABRIC,
AS A SYSTEM--
THIS SYSTEM--
WOULD GET US THROUGH
THE HYPERSONIC PHASE VERY NICELY
FROM THE LARGE DEPLOYMENT
PERSPECTIVE.
THERE'S ALSO ANOTHER
ADVANTAGE TO THIS.
WHEN YOU USE CARBON,
YOU CAN USE THEM REPEATEDLY.
YOU CAN DO AEROCAPTURE,
AND THEN YOU COOL DOWN IN SPACE,
AND THEN COME BACK
AND DO ENTRY, DESCENT, LANDING,
UNLIKE INFLATABLES.
INFLATABLES, YOU HAVE TO THINK
ABOUT THAT PROBLEM
VERY SERIOUSLY.
BUT WHAT WE CAN DO--
WE HAVEN'T DONE IT--
THAT J.P.L. IS VERY INTERESTED
IN THIS,
IS TO USE THIS IN CONJUNCTION
WITH THE SUPERSONIC PARACHUTES
THEY ARE DEVELOPING THAT ARE
GOING TO BE FLYING IN HAWAII--
THEY WERE PLANNING TO FLY,
OR THE INFLATABLE--
THAT SUPERSONIC INFLATABLE.
THAT MAY PROVIDE
AN ADDITIONAL DRAG.
NOW WHAT WE HAVE THOUGHT OF
IS TO DO DOUBLE DEPLOYMENT,
ONE DURING AEROCAPTURE
AND THEN ONE
FOR ENTRY, DESCENT, LANDING.
THAT WOULD BE
A MUCH LARGER SURFACE,
UP TO 33-METER DIAMETER.
FOR US TO THINK ABOUT 23-METER--
IF YOU THINK ABOUT--
IF YOU OPEN YOUR EYES
AND LOOK ABOUT,
AT THIS CEILING HEIGHT,
23 METERS IS LARGER
THAN OUR EYE CAN SEE.
33 METERS IS EVEN LARGER.
SO THINKING ABOUT THOSE LARGE
SYSTEMS STARTS TO HURT
YOUR BRAIN,
UNTIL WE GO BUILD THINGS.
AND THEN IT MAKES IT EASIER.
OKAY.
THERE WAS--
- SO YOU MENTIONED TESTING
THIS MATERIAL
IN THE PEAK HEAT LOAD
FOR MARS AND VENUS E.D.L.
IT LOOKED, THOUGH, LIKE YOU HAD
THE MATERIAL PRESSED UP AGAINST
A COLD SOAK OF METAL
DURING THE TEST.
HAS IT BEEN TESTED IN
A SITUATION WHERE IT RECEIVES
NOT ONLY THE THERMAL LOAD
OF MARS E.D.L.,
BUT IN THIS SITUATION,
WHERE THERE'S NOTHING FOR IT
TO REJECT THE HEAT TO OTHER
THAN THE SPACE BEHIND IT?
- PERFECT OBSERVATION THERE.
THE MATERIAL--
THE TEST ARTICLE THAT YOU SAW,
IT WAS A FRAME,
LIKE A PICTURE FRAME,
WHERE ON THE EDGE,
YOU'RE HOLDING THE FABRIC
AROUND A PICTURE FRAME.
IN THE MIDDLE OF IT,
THERE'S NOTHING BEHIND.
THE FLOW CAN GO THROUGH IT.
SO EVEN THOUGH I DIDN'T
SHOW YOU THAT DETAIL,
WE HAVE DONE TESTING
AT J.S.E. ARC JET,
AT AMES ARC JET,
AT DIFFERENT CONDITIONS
WHERE THE FABRIC ALLOWS THE FLOW
TO GO THROUGH IF THE FLOW
PENETRATES THE FABRIC.
SO IT'S VERY SIMILAR
TO WHAT WE'D EXPERIENCE.
IT GETS HEATED UP
TO 2,300 DEGREES KELVIN,
2,200 TO 2,300 DEGREES.
AND THEN IT RADIATES
ON BOTH SIDES.
AND THE FRAME DEFINITELY
HAS AN EFFECT ON KEEPING
THE FABRIC
AROUND THE EDGE COOLER.
BUT THE AMOUNT OF HEAT WE ARE
PUTTING IN AT THE MIDDLE
OF THE FABRIC,
IT IS EXPERIENCING BOTH THERMAL
AND MECHANICAL LOADS.
SO IT IS A CHALLENGE FOR US TO
BUILD THOSE KINDS OF ARTICLES.
THIS IS THE FIRST TIME
WE HAVE DONE THAT IN THE AMES--
IN ANY ARC JET,
THOSE KINDS OF LOADS,
MECHANICAL AND THERMAL.
SO WE CALL THIS
A THERMOMECHANICAL TEST.
YES?
- SO PLEASE JOIN ME
IN THANKING RAJ AGAIN
FOR AN EXCELLENT PRESENTATION.
[audience applauds]
[musical tones]
[electronic sounds of data]
