r.traj

NAME

r.traj - Ballistic trajectory modeling program.
(GRASS Raster Program)

SYNOPSIS

r.traj
r.traj help
r.traj input=name output=name weapon=name coordinate=x,y elevation=value ammunition=name left.azimuth=name right.azimuth=name

DESCRIPTION

r.traj generates a raster map layer showing cells that can be hit from a firing point by shells from a user-specified weapon. Cells are marked with integer values that represent the muzzle firing angles required to hit them.

COMMAND LINE OPTIONS

Parameters:

input=name

Name of the elevation raster map.

output=name

Name of new raster map containing results.

weapon=name

Type of weapon used for firing. A list of weapon types and their associated attributes are kept in the file $GISBASE/weapon_data/weapons.

coordinate=x,y

The coordinates of the firing point (east, north).

elevation=value

Maximum weapon muzzle elevation.

ammunition=name

Type of ammunition. A list of ammunition types and their associated attributes are kept in the file $GISBASE/weapon_data/ammunition.

left.azimuth=name

Far left edge of allowable firing azimuth. The angle will be in the form of:

[NS]0-90[EW]

For example, S60E indicates the angle is 60 degrees East of true South.

right.azimuth=name

Far right edge of allowable firing azimuth, stated in same form as left.azimuth.

Category values in the output raster map layer will program results. Category values between -89 and 89 indicate the gun elevation angle in degrees needed to hit that cell. A category value of 90 is assigned to the weapon's firing point. A category value of -90 is assigned to those points unhittable by the weapon.

EXAMPLE

r.traj input=elevation output=name weapon=M1 coordinate=600000.0,4920000.0
elevation=2.5 ammunition=M392 left.azimuth=S30E right.azimuth=S25W

WEAPON AND AMMUNITION TYPES

Weapon types and their attribute types are listed below. These can be listed by running the program r.traj.data.

                       +----------------------+
                       |Weapon Type           |
                       +----------------------+
                       |M48        19   -9    |
                       |M1         20   -9    |
                       |M101       66   -5    |
                       |M102       75   -5    |
                       +----------------------+

Ammunition types and their attributes are listed below. These can be displayed by running the program r.traj.data.

                  +--------------------------------+
                  |Ammo Type                       |
                  +--------------------------------+
                  |M392        105   18.60   1458  |
                  |M392A2      105   18.60   1458  |
                  |M728        105   18.95   1426  |
                  |M735        105   23.05   1501  |
                  |M735A1      105   17.24   1508  |
                  |M774        105   17.23   1508  |
                  |M494        105   24.9     821  |
                  |M456        105   21.78   1173  |
                  |M416        105   20.68    737  |
                  |M467        105   20.42    730  |
                  |M490        105   20.41   1170  |
                  |M724        105   14.51   1507  |
                  |M724A1      105   14.51   1539  |
                  |M737        105    9.44   1539  |
                  |M393        105   20.41    732  |
                  +--------------------------------+

AUTHORS

Chuck Ehlschlaeger, U.S. Army Construction Engineering Research Laboratory
Kewan Q. Khawaja, Intelligent Engineering Systems Laboratory, M.I.T.