The slides give a glimpse of the new upcoming technology that is ready to change the definition of space travel. More economically efficient and less risky approach that does not put space travellers life at stake........

1. LEAVING THE PLANET BY
SPACE ELEVATOR
PRESENTED BY: PANKAJ SHARMA, 3RD YEAR, MECHANICAL ENGG DEPTT.

2. A BRIEF HISTORY
19th CENTURY:
The key concept of the space elevator appeared in 1895
when Russian scientist Konstantin Tsiolkovsky was inspired by the Eiffel
Tower in Paris. He considered a similar tower that reached all the way into
space and was built from the ground up to the altitude of 35,790
kilometers.
20th CENTURY:
In 1929, Authur Clarke, the famous science fiction writer and futurist, in his
novel Fountains of Paradise describes the concept of the space elevator

3. NEED FOR AN ALTERNATE SPACE
TRANSPORT SYSTEM
The present day space
transportation systems based
on rocket launches are:
1. Economically inefficient.
2. Involve huge risk factors.

4. WHAT IS A SPACE ELEVATOR?
Space elevators are
incredibly tall
theoretical structures
that stretch beyond
the earth’s
atmosphere to
transport satellites
and shuttles into outer
space without the cost
and environmental
impact of rocket
fueled launches

5. How could it be done?
• A space elevator made of
ribbon anchored to an offshore
sea platform
• Ribbon would stretch to a small
counterweight approximately
62,000 miles (100,000 km) into
space due to rotation of earth
about its own axis
• Mechanical lifters attached to the
ribbon would then climb the
ribbon, carrying cargo and humans
into space using different
mechanisms.

6. WORKING PRINCIPLE
The centrifugal force of
earth’s rotation is the
basic principle behind the
working of elevator. Due
to the earth’s rotation, the
centrifugal force acting
radially outwards help to
keep the elevator cable
taught.

7. MAIN COMPONENTS
 The Ribbon
 The Anchors
 The Climbers
 The Power

8. THE RIBBON (TETHER)
 The cable in a space elevator must be
strong enough to carry its own weight
as well as the weight of the climber.
 The cable should be very light and
flexible.
 The required properties of the cable
material are satisfied by a recently
synthesized material known as
CARBON NANOTUBES.

9. WHAT IS A CARBON NANOTUBE?
A Carbon Nanotube can be
thought of as a sheet of
hexagonal lattice of carbon
rolled in the form of a
cylindrical tube with
exceptionally useful
properties.
They are also referred as
THE WONDER MATERIAL

10. WHY CARBON NANOTUBES?
Property Single Walled
Nanotubes
Metal wires
Tensile Strength 45 billion pascals High strength
steel alloys break
at about 2 billon
pascal
Resilience Can be bent at
large angles and
restraightened
without damage
Metals and carbon
fibers fracture at
grain boundaries
Temperature
stability
Stable upto 2800
degrees in
vacuum, 750
degrees in air
Metal wire in
microchips melt at
600 to 1000
degrees C

11. FABRICATION OF NANOTUBES
Techniques have been developed to produce nanotubes in sizable quantities, including
arc discharge, laser ablation, high-pressure carbon monoxide disproportionation,
and chemical vapor deposition (CVD).

12. Anchor
 Anchor station is a mobile, ocean-going platform
identical to ones used in oil drilling.
 Anchor is located in eastern equatorial pacific
(GALAPAGOS ISLANDS )
 Weather and mobility are primary factors in
positioning of the anchor

13. Climbers
 Initial ~200 climbers used to build
nano-ribbon.
 Later used as launch vehicles for
payloads from 20,000- 1,000,000
kg, at velocities up to 200km/hr
 Climbers powered by electron
laser & photovoltaic cells, with
power requirements of 1.4-
120MW

14. Power Beaming Propulsion
 Free-electron lasers used to
deliver power
 Adaptive Optics on Hobby-Eberly
telescope used to focus Earth-
based beams, (25cm spot @
1,000km altitude)
 Reduced power delivered at high
altitudes compensated by reduced
gravitational force on climber,
(~0.1g)

15. Continued…
 The laser will beam 2.4
megawatts of energy to
photovoltaic cells, perhaps made
of Gallium Arsenide (GaAs)
attached to the lifter,
 It will then convert that energy
to electricity to be used by
conventional, niobium-magnet
DC electric motors
 In 2009, NASA awarded
$900,000 to Laser Motive for
their successful demonstration of
"wireless power transmission" for
space elevator

16. SPACE ELEVATOR – THE FUTURE
While rockets will undoubtedly improve greatly in efficiency there is a limit to how
efficient they can become.
CURRENT
Cost of a launch $10,000 per
pound ($22,000 per kg)
Huge vibrations produced and
rocket fuel and hardware required
which can’t be reused .
Riding on a continuous and
giant explosion is
extraordinarily dangerous
ELEVATOR
Cost of launch $250 per
pound ($660 per kg).
Less vibrations produced and
less hardware required and
can be used almost every day
for space travel.
Safe access to space - no
explosive propellants or
dangerous launch.

17. Applications
 Solar power satellites - economical, clean power for use on
Earth
 Solar System Exploration - colonization and full development
of the moon, Mars and Earth orbit
 Telecommunications - enables extremely high performance
systems

18. Next Steps…
 Material development efforts are
underway by private industry
 Engineering development centers in
the U.S., Spain and Netherlands are
under development
 Japanese construction giant
OBOYASHI CORPORATION has
undertaken the project to build a fully
functional space elevator by the year
2050.

19. MAJOR HURDLES
 Ribbon Construction
 Atmospheric:
Lightning
High Winds
Atomic Oxygen
Orbital:
Meteors
Low orbit object

20. CONCLUSION
Space elevator can be very well understood as the future of
space travel and a technology that will help to spread the human
civilization beyond earth…..

21. THANK YOU