Transcript Re-entry Vehicles - Mount Holyoke College

Mission Mars
ENTRY, DESCENT AND
LANDING
What are we going to Talk about?
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What are we going to Talk about?
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History of Landers
What are we going to Talk about?
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History of Landers
How do these Landers work?
What are we going to Talk about?
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History of Landers
How do these Landers work?
Primary Lander Configuration
What are we going to Talk about?
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History of Landers
How Do these Landers work?
Primary Lander Configuration
Emphasis on the Aero shell design,
using MER.
History of Mars Landers
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SOVIET UNION
Lander
Aero shell Design
Aero braking to 600 m/s
Deployment of Parachutes
Descent with Retro
rockets
Failure
History of Mars Landers
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United States
Orbital Entry
Aero shell Design
Aero braking
Parachute Deployment
Retrorocket
Soft landing on Legs( On
Mission)
Science Behind the Landing
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Type of entry procedures
1.
Ballistic Entry
2.
Double Dip Entry
3.
Aero – braking
Ballistic Method
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Thick Heat Shield
Steep angle of flight, greater
deceleration with high accuracy.
The disadvantage
Double Dip Method
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Double Dip entry, takes advantage of
the lift of the vehicle to make two
decelerating dips into the
atmosphere
the heat transferred is more gradual,
allowing the use of a thinner heat
shield that relies on radiating the
heat
Aero Braking
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Multiple passes through the
atmosphere to gradually slow the
vehicle.
the dynamic nature of planetary
atmospheres, resulting in uncertainty
about the state of the atmosphere at
the time of entry.
Entry Vehicle
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Aeroshell
Aeroshell
The Aeroshell
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Heat Shield
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The Backshell
Heat Shield
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Protects the ship from intense heat
from entry.
Backshell
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a parachute (stowed at the top of the
backshell)
an Inertial Measurement Unit (IMU)
three large solid rocket motors called RAD
(Rocket Assisted Descent),
three small solid rockets called TIRS
Composition of Backshell
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the aeroshell is made out of an
aluminum honeycomb structure
sandwiched between graphite-epoxy
face sheets.
Outside covered with a layer of phenoic
compound.
Albator
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It is specially formulated to react
chemically with the Martian atmosphere
during entry and essentially take heat
away, leaving a hot wake of gas behind
the vehicle.
instead of being painted, the backshell will
be covered with a very thin aluminized
mylar blanket to protect it from the cold of
deep space.
I.M.U
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IMU Inertial Measurement Unit
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Northrop Grumman
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LN200S
Parachute
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Mission
Requirements
(Load)
System
Composition
System Operation
(Automatic
Deployment)
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Rocket Assisted Descent
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Pathfinder Manufacture:
Zirkol
MER Manufacturer
ATK.
1 ton thrust in 3 sec
30- 50 feet
atmospheric hover.
Transverse Impulse Rocket System
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Implementation:
Trajectory correction in
flight during descent.
ATK manufactured.
Airbags
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Robust Design
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Multi-bladder
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Material
Video
Questions
Pics: Nasa.gov