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A. K. Misra and S. Cohen
Fig. 1 Schematic diagram of the space elevator (modified from: https://en.wikipedia.org/wiki/
Space_elevator)
Calculations show that the stress that will develop in a full space elevator is too
high for conventional engineering materials, although advanced new materials, such
as carbon nanotubes, are capable of handling such stress. Unfortunately, the current
technology is not yet advanced enough to build such a large structure using carbon
nanotubes. Hence, it is expected that a partial elevator will be constructed first using
conventional materials, providing only partial benefits of a space elevator. A full
space elevator will be built subsequently.
This article examines the mechanics of space elevators. To start with, a brief
discussion of the satellite placement capability of a full space elevator is discussed.
This is followed by the analysis of the statics and dynamics of a full space elevator.
2 Satellite Placement Using a Space Elevator
Figure 1 shows the main components of the space elevator. It consists of a ribbon,
a counterweight, and one or more climbers, all in the equatorial plane of the Earth.
The ribbon is in tension due to the gravity and centrifugal gradients, which act in
opposite directions. The climber, propelled by an electric motor, will ascend the
ribbon, transporting payloads to various altitudes.
Once a climber reaches a desired launch altitude, d 0 , the satellite it contains may
be released. If no additional velocity impulse is added to the satellite at its time of
launch, it will have used no fuel to arrive in orbit. These orbits are called free Earth
orbits.
A. K. Misra and S. Cohen
Fig. 1 Schematic diagram of the space elevator (modified from: https://en.wikipedia.org/wiki/
Space_elevator)
Calculations show that the stress that will develop in a full space elevator is too
high for conventional engineering materials, although advanced new materials, such
as carbon nanotubes, are capable of handling such stress. Unfortunately, the current
technology is not yet advanced enough to build such a large structure using carbon
nanotubes. Hence, it is expected that a partial elevator will be constructed first using
conventional materials, providing only partial benefits of a space elevator. A full
space elevator will be built subsequently.
This article examines the mechanics of space elevators. To start with, a brief
discussion of the satellite placement capability of a full space elevator is discussed.
This is followed by the analysis of the statics and dynamics of a full space elevator.
2 Satellite Placement Using a Space Elevator
Figure 1 shows the main components of the space elevator. It consists of a ribbon,
a counterweight, and one or more climbers, all in the equatorial plane of the Earth.
The ribbon is in tension due to the gravity and centrifugal gradients, which act in
opposite directions. The climber, propelled by an electric motor, will ascend the
ribbon, transporting payloads to various altitudes.
Once a climber reaches a desired launch altitude, d 0 , the satellite it contains may
be released. If no additional velocity impulse is added to the satellite at its time of
launch, it will have used no fuel to arrive in orbit. These orbits are called free Earth
orbits.