scripts/TP1 05.15 Comet.AESL

   1 IDENTIFICATION DIVISION
   2 PROGRAM-ID Comet
   3 VERSION 20240205
   4 COMMENT A comet moves on a parabolic orbit in the gravitational field of the stationary sun.
   5 COMMENT Its orbital plane coincides with the plane of the Earth's orbit, which is assumed to be circular.
   6 COMMENT The perihelion distance is one third of the Earth's orbital radius R.E.
   7 COMMENT How long does the comet move within the Earth's orbit?
   8 COMMENT t(r)=root(2/(gamma*m(sun))*integral from 1/3RE to RE (r/root(r-1/3 RE)) dr
   9
  10 ENVIRONMENT DIVISION
  11 ENGINE Anabrid-THAT
  12 TIMEBASE 100ms # use SLOW on both integrators
  13 REQUIRES COEFFICIENT 3, INTEGRATOR 2, COMPARATOR 1, SUMMER 1, OPEN-AMP 2, MULTIPLIER 2, INVERTER 1
  14
  15 DATA DIVISION
  16 OUTPUT OUTPUT.X -xlimited
  17 OUTPUT OUTPUT.Y result
  18 COEFFICIENT.1 Factor # root(2/(gamma*m)), scaled to 0,142 10kd/Tm^3/2
  19 COEFFICIENT.2 RE # Earth's orbital radius, scaled to 0,150 Tm
  20 COEFFICIENT.3 1/3RE # note: dependent on RE, scaled to 0,05 Tm
  21
  22 PROGRAM DIVISION
  23 +1 -> COEFFICIENT.RE -> RE
  24 +1 -> COEFFICIENT.1/3RE -> 1/3RE
  25
  26 # obtaining x through integration of 1, starting at 1/3RE
  27 +1, IC:1/3RE -> INTEGRATOR -> -x
  28
  29 # limiting x to the upper limit of the integral RE and set x=0 if beyond
  30 A:-x, B:RE, GT0:-x -> COMPARATOR -> -xlimited
  31
  32 -xlimited, 1/3RE -> SUMMER -> -(-x+1/3RE)=x-1/3RE
  33
  34 # root of x-1/3RE
  35 ## first invert because the input of a root has to be negative
  36 x-1/3RE -> INVERTER -> -(x-1/3RE)
  37 ## now make sure the input is never >0 (which causes the circuit to error)
  38 A:-(x-1/3RE), LT0:-(x-1/3RE) -> COMPARATOR -> -(x-1/3RE)limited
  39 ## now calculate the root
  40 -(x-1/3RE)limited, OA1 -> OPEN-AMP -> root
  41 root, root -> MULTIPLIER -> OA1
  42
  43 # x/root
  44 -xlimited, OA2 -> OPEN-AMP -> x/root
  45 x/root, root -> MULTIPLIER -> OA2
  46
  47 # integral
  48 x/root -> INTEGRATOR -> integral
  49 integral -> COEFFICIENT.Factor -> result
  50
  51 OPERATION DIVISION
  52 MODE REPEAT
  53 OP-TIME 111ms