Title: On The Need for Lunar Lander Simulations: A Human Factors Perspective
1- On The Need for Lunar Lander Simulations A Human
Factors Perspective - Robert S. McCann
- Human-Systems Integration Division
- NASA Ames Research Center
Go For Lunar Landing Conference March 5 2008
2Human Factors of Lunar Landing Simulations
- Apollo all landings near-side equatorial
- LEM operations concept heavily dependent on
real-time communications loop with the ground - Preliminary Altair Concept of Operations
- Anywhere, anytime landing capabilities
- Includes polar and far-side targets
- Strong possibility of autonomous descent and
landing operations requirement
3Lunar Lander Descent and Landing Operations
- What is the workload associated with the task?
- What are the task related crew-vehicle interfaces?
4Lessons Learned from Apollo 11 Operations
Workload
- Apollo Operational Workload Assessment
- The most difficult part of the entire mission
from my perspective, and the one that gave me the
most pause, was the final descent to landing - far and away the most complex part of the
flight - systems were very heavily loaded at that time
- the unknowns were rampant
- there were just a thousand things to worry
about It was hardest for the system and it was
hardest for the crews to complete that part of
the flight successfully - - Neil Armstrong, September 2001
5Apollo 11 LEM Descent and Landing Operations
- 1023826 Armstrong (With the slightest touch of
urgency) Program Alarm. - 1023830 Armstrong (To Houston) It's a 1202.
- 1023832 Aldrin 1202. (Pause)
- 1023842 Armstrong (on-board) (To Buzz) What is
it? - (To Houston) Give us a reading on the 1202
Program Alarm. - 1023853 Duke Roger. We got you...(With some
urgency in his voice) - We're Go on that alarm.
6Apollo 11 Operations
- I was very much in the dark when this came up.
- - Buzz Aldrin
- Our most knowledgeable NASA software engineer
advised Mission Control to inform the astronauts
to push on. It was a gutsy call. - - Fred H. Martin, M.I.T. Instrumentation
Laboratory
7Apollo LEM Operations
- Second Malfunction Descent and Landing Phase
Trajectory Management
Inner-loop Flight Control
Systems Health Management
8Lessons Learned from Apollo 11 Operations
- 1024445 Aldrin 100 feet, 3 1/2 down, 9
forward. Five percent (fuel remaining). Quantity
light. - Quantity light indicated that 5.6 of the
original propellant load remained -
- Started a 94-second countdown to a 'Bingo' fuel
call which meant land in 20 seconds or abort -
- If you're 50 feet up at 'bingo fuel' with all of
your horizontal rates nulled and are coming down
to a good spot, you could certainly continue to
land At anything over 100 feet, you'd punch the
abort button and say goodbye to the moon - Quantity light was based on erroneous sensor
reading
9Lessons Learned from Apollo 11 Operations
- As we got lower, the visibility continued to
decrease. - The thing that was confusing to me was that it
was hard to pick out what your lateral and
downrange velocities were, because you were
seeing a lot of moving dust that you had to look
through to pick up the stationary rocks and base
your translational velocity decisions on that. - I found that to be quite difficult.
- As we approached the ground, I still had a left
translational rate which made me reluctant to
shut the engine off while I still had that rate.
I was also reluctant to slow down my descent rate
anymore than it was, or stop (the descent),
because we were close to running out of fuel. We
were hitting our abort limit." - - Neil Armstrong
10Lessons Learned from Apollo 11 Operations
- Workload with Apollos (or even shuttles) level
of onboard decision-making and systems management
support could very likely have overloaded the
crew - Autonomous operational concept for
descent/landing requires the development of
various forms of onboard decision support tools - Systems health management tools (e.g. Advanced
Caution and Warning System) - Automated flight control tools
- Automated mission management support tools
11Lessons Learned from Apollo 11 Operations
- Infusing automated support tools for autonomous
descent and landing operations raises a host of
operational concept definition issues, such as - Determining the appropriate crew-machine
functional allocation (level of automation) from
the well-known levels of automation scales (e.g.,
Sheridan-Verplank) - Designing crew interfaces with automation to
- A) enable crew to maintain situation awareness
of automated actions and their causes - B) enable smooth reversion to manual control in
the event of automation failure - Promoting effective crew resource management
12Altair Ops Concepts Definition
- These operational concept development issues
create an urgent need to design, develop, test,
and validate - Decision support software
- Autonomous operational concepts that involve the
decision support software via human-in-the-loop
simulation - Failure to do so in a timely manner raises
considerable risk that autonomous descent and
landing operations will fail constellation
human-system integration requirements for
operational error and crew workload