Difference between revisions of "Mass Drivers"

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  == Circum Polar Mass Driver ==  
 
  == Circum Polar Mass Driver ==  
  
There have been many suggestions for mass drivers on Luna for the exportation of raw materials and other purposes, notably by Gerard K. O'Neill (God rest his soul) and the Space Studies Institute.  Plans can keep the power requirement low by calling for a low payload size.  Higher acceleration rates allow shorter track.   High firing rates keep the investment actively earning its return.   
+
  There have been many suggestions for mass drivers on Luna for the exportation of
 +
raw materials and other purposes, notably by Gerard K. O'Neill (God rest his soul)
 +
and the Space Studies Institute.  Plans can keep the power requirement low by
 +
calling for a low payload size.  Higher acceleration rates allow shorter track.
 +
High firing rates keep the investment actively earning its return.   
 
   
 
   
I consider here a circular mass driver or mass accelerator which would keep power requirements low by spreading the acceleration out over many laps of a circular track.  The payload could be about 200 kilograms.  If there are passengers or cargo available every 110 minutes for rendezvous with a catcher satelite, it can keep constantly busy.  Suitability for passenger service requires a low radial acceleration, I specify 30 meters per second squared (about 3 g's).  This in turn requires a large diameter (about 120 miles).  The shape of the device is like a very regular volcanic mountain peak with gently sloping sides and a circular crater on top.  The accelerator track would run along the vertical wall of the
+
  I consider here a circular mass driver or mass accelerator which would keep power
circular crater.  When the payload and carrier reach orbital velocity (1680 meters per second), the payload is dropped radially outward over the top of the wall.  A counter weight may be required on the carrier near the base of the wall to ballance the carrier.  Since the diameter of the track is 120 miles, there is
+
requirements low by spreading the acceleration out over many laps of a circular
about one and two thirds miles bulge of the curvature of Luna interfering with line of sight communication from one side of the track to the other.  The plane of the circular track makes a 3.2 degree angle with the surface of Luna.  Payloads launched tangentialy from the track, however, deviate from that plane by curving downward toward Luna in a orbital path.  This makes it more likely than otherwise that a payload would smash into a mountain peak.  So the accelerator track should be built up on fill as high as practical and care should be taken in choosing the exact dirrection of launch.  The circular accelerator should be centered at the North pole while the catcher satelite would orbit about once per 110 minutes at an inclination of about 86.8 degrees.  So it would pass over one or another spot on the circular track with every orbit as Luna rotates under the orbit.  It could catch a payload whenever a mountain peak did not interfere.  Troublesome peaks could be razed.   
+
track.  The payload could be about 200 kilograms.  If there are passengers or
 +
cargo available every 110 minutes for rendezvous with a catcher satelite, it can
 +
keep constantly busy.  Suitability for passenger service requires a low radial
 +
acceleration, I specify 30 meters per second squared (about 3 g's).  This in turn
 +
requires a large diameter (about 120 miles).  The shape of the device is like a
 +
very regular volcanic mountain peak with gently sloping sides and a circular
 +
crater on top.  The accelerator track would run along the vertical wall of the
 +
circular crater.  When the payload and carrier reach orbital velocity (1680 meters
 +
per second), the payload is dropped radially outward over the top of the wall.  A
 +
counter weight may be required on the carrier near the base of the wall to
 +
ballance the carrier.  Since the diameter of the track is 120 miles, there is
 +
about one and two thirds miles bulge of the curvature of Luna interfering with
 +
line of sight communication from one side of the track to the other.  The plane of
 +
the circular track makes a 3.2 degree angle with the surface of Luna.  Payloads
 +
launched tangentialy from the track, however, deviate from that plane by curving
 +
downward toward Luna in a orbital path.  This makes it more likely than otherwise
 +
that a payload would smash into a mountain peak.  So the accelerator track should
 +
be built up on fill as high as practical and care should be taken in choosing the
 +
exact dirrection of launch.  The circular accelerator should be centered at the
 +
North pole while the catcher satelite would orbit about once per 110 minutes at an
 +
inclination of about 86.8 degrees.  So it would pass over one or another spot on
 +
the circular track with every orbit as Luna rotates under the orbit.  It could
 +
catch a payload whenever a mountain peak did not interfere.  Troublesome peaks
 +
could be razed.   
  
  The above specifications would require 43 kilowatts average power put constantly into payloads plus power to accelerate the carrier and allow for the losses in magnetic levitation.  Unfortunately, the carrier can not constantly accelerate because it must come to a stop to be ready to pick up the next payload.  Two tracks, one of 10 meters less radius and 2 meters more altitude than the first would allow one track to accelerate while the other uses regenerative braking.  As long as we consider developments that must be many years in the future, there is a capability of adding carriers in a train as there is increased available power and  need for cargo tonnage.  The whole 370 mile circumference of the accelerator could be filled with one train of carriers.  The payloads could be connected by rope and the whole train of payloads launched from one point on the cicomference into one orbit as 5 minutes and 53 seconds go by.  
+
  The above specifications would require 43 kilowatts average power put constantly
 +
into payloads plus power to accelerate the carrier and allow for the losses in
 +
magnetic levitation.  Unfortunately, the carrier can not constantly accelerate
 +
because it must come to a stop to be ready to pick up the next payload.  Two
 +
tracks, one of 10 meters less radius and 2 meters more altitude than the first
 +
would allow one track to accelerate while the other uses regenerative braking.  As
 +
long as we consider developments that must be many years in the future, there is a
 +
capability of adding carriers in a train as there is increased available power
 +
and  need for cargo tonnage.  The whole 370 mile circumference of the accelerator
 +
could be filled with one train of carriers.  The payloads could be connected by
 +
rope and the whole train of payloads launched from one point on the cicomference
 +
into one orbit as 5 minutes and 53 seconds go by.  
  
 
----  --[[User:Farred|Farred]] 14:56, 1 May 2008 (UTC)
 
----  --[[User:Farred|Farred]] 14:56, 1 May 2008 (UTC)

Revision as of 07:03, 1 May 2008

== Circum Polar Mass Driver == 
 There have been many suggestions for mass drivers on Luna for the exportation of
raw materials and other purposes, notably by Gerard K. O'Neill (God rest his soul)
and the Space Studies Institute.  Plans can keep the power requirement low by
calling for a low payload size.  Higher acceleration rates allow shorter track.  
High firing rates keep the investment actively earning its return.  

 I consider here a circular mass driver or mass accelerator which would keep power
requirements low by spreading the acceleration out over many laps of a circular
track.  The payload could be about 200 kilograms.  If there are passengers or
cargo available every 110 minutes for rendezvous with a catcher satelite, it can
keep constantly busy.  Suitability for passenger service requires a low radial
acceleration, I specify 30 meters per second squared (about 3 g's).  This in turn
requires a large diameter (about 120 miles).  The shape of the device is like a
very regular volcanic mountain peak with gently sloping sides and a circular
crater on top.  The accelerator track would run along the vertical wall of the
circular crater.  When the payload and carrier reach orbital velocity (1680 meters
per second), the payload is dropped radially outward over the top of the wall.  A
counter weight may be required on the carrier near the base of the wall to
ballance the carrier.  Since the diameter of the track is 120 miles, there is
about one and two thirds miles bulge of the curvature of Luna interfering with
line of sight communication from one side of the track to the other.  The plane of
the circular track makes a 3.2 degree angle with the surface of Luna.  Payloads
launched tangentialy from the track, however, deviate from that plane by curving
downward toward Luna in a orbital path.  This makes it more likely than otherwise
that a payload would smash into a mountain peak.  So the accelerator track should
be built up on fill as high as practical and care should be taken in choosing the
exact dirrection of launch.  The circular accelerator should be centered at the
North pole while the catcher satelite would orbit about once per 110 minutes at an
inclination of about 86.8 degrees.  So it would pass over one or another spot on
the circular track with every orbit as Luna rotates under the orbit.  It could
catch a payload whenever a mountain peak did not interfere.  Troublesome peaks
could be razed.  
The above specifications would require 43 kilowatts average power put constantly
into payloads plus power to accelerate the carrier and allow for the losses in
magnetic levitation.  Unfortunately, the carrier can not constantly accelerate
because it must come to a stop to be ready to pick up the next payload.  Two
tracks, one of 10 meters less radius and 2 meters more altitude than the first
would allow one track to accelerate while the other uses regenerative braking.  As
long as we consider developments that must be many years in the future, there is a
capability of adding carriers in a train as there is increased available power
and  need for cargo tonnage.  The whole 370 mile circumference of the accelerator
could be filled with one train of carriers.  The payloads could be connected by
rope and the whole train of payloads launched from one point on the cicomference
into one orbit as 5 minutes and 53 seconds go by. 

--Farred 14:56, 1 May 2008 (UTC)