In another world

Wed, 08 Aug 2012 16:28:00 +1000

By Dr Mick Fielding

It was barely seven weeks after Geelong won the 2011 AFL grand final that the long journey began.

For those involved, it marked the end of one chapter and the beginning of the next, ever more exciting step.

It has taken the commitment of many hundreds of workers contributing 100's of thousands of hours of effort to solve myriad engineering and software issues.

Simply, it is their baby.  Powered by a radioisotope thermoelectric generator, full of sensors and computers, its name is Curiosity.  And there it sits, 58 metres off the ground, cradled helplessly in the payload bay of an Atlas V rocket waiting for the programmed launch sequence to command its main solid fuel engine and four solid rocket boosters (SRBs) to erupt in a spectacular display of fire and exhaust, collectively producing a mind-blowing thrust equal to the force it would take to hold 210 Ford Territories stacked on each other.

"T minus 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, main engines started.  Zero, and we have lift off of the Altas V with Curiosity, seeking clues to the planetary puzzle about life on Mars.”

Amazing words and an indelible experience for all who witnessed it either in person or, as I did, via NASA’s video stream.  

Skip forward to the morning of August 6, 2012.  For the past 254 days the cruise stage payload of the Atlas V has been hurtling towards its rendezvous with Mars.  A reasonably quick trip, but not surprising given its rather brisk pace of 21,200kmh, the equivalent of running an Olympic 100m in about 1/60th of a second or driving from Geelong to Sydney in about 2.5 minutes.

What is to be attempted next will make being kicked off this Earth by a 330 tonne solid fuel launch pole look like a walk in the park.  

The flight control team monitors the telemetry data being received from Curiosity.

As the craft prepares for the seven minute descent through the Martian atmosphere, nicknamed the “Seven Seconds of Terror” it is flying fully autonomously, as it has done for the majority of its journey.  Even if the scientists back at mission control wanted to make a change, it is too late!

Curiosity is on her own. It is now all up to the 500,000 lines of code programmed into the on-board control systems.  

As the craft enters the thin Martian atmosphere its heat-shield climbs to a temperature of 2100℃, enough to easily melt steel. The friction against the new generation heat shield causes the craft to slow and at about 1600kmh the one-of-a-kind super-sonic parachute is deployed.

The 30,000kg of drag from this 50kg parachute slows Curiosity to 320kmh.

The heat shield is jettisoned exposing the final decent stage - the six-wheeled rover and the rocket propelled sky crane.

As the final stage drops away from the parachute a series of small rockets are used to slow and stabilise the vertical and horizontal velocity of the lander.

On-board sensors steer the craft until it is hovering above the designated landing zone.

NASA engineers knew that as thrust from the rockets, it would stir up lots of dust and debris that could damage the rover, so they came up with the ingenious solution of lowering the rover  via a 6.5 meter tether using the 'sky crane manoeuvre'. 

Twenty meters above the surface and with the rover now hanging 6.5 meters below, the rocket stage slowly descends until the wheels of the rover give the signal that they have touched down safely on the surface of Mars.  

At this exact moment the tether is severed from the rover and the rocket stage blasts off into the distance.  

Barely a couple of minutes after the 'successful landing' messages arrive at NASA the first images start showing up.  Low resolution to begin with, nevertheless they confirm this insanely ambitious landing has been achieved.

I am part of the Centre for Intelligent Systems Research (CISR) at Deakin University's Waurn Ponds campus.  

We work on advanced motion simulators for training combat pilots and race-car drivers, bomb-disposal robots and delicate medical training devices for doctors and nurses.  

Every day of the week I sit alongside some of the coolest and most interesting people and technology on our planet.

But I will never forget how 30 of my colleagues were drawn away from their work to the live video feed from NASA on our big presentation screen.  

Or the jubilation and relief on their faces.  

Like the men and women of NASA, we all felt connected by this brilliant success of mankind and machine that turned the seemingly impossible into just another day in the office.


Dr Mick Fielding
Dr Mick Fielding with some of his favourite toys.
Deakin Research Commercial
Showcase facts
  • Like the men and women of NASA, CISR staff all felt connected by this brilliant success of mankind and machine that turned the seemingly impossible into just another day in the office.
Facebook

Deakin University acknowledges the traditional land owners of present campus sites.

20th August 2012