Post-Processing Drafts, Points, and Sensor Readings Post-Processing Drafts, Points, and Sensor Readings

One class of command is always available within the Process Post-Processing Menu - the ones which deal with Interest points, Draft Marks, and Sensors. There are four commands available: SENSOR, DRAFT, POINTS, REL_MOTION, and P_MIN_DISTANCE.

The options common to most commands here are:


     -EVENTS, EVE_BEGIN, EVE_END, EVE_INC

     -MAG_DEFINE, A(1), .. A(n)

The -EVENTS option selects the events which will be considered. Here EVE_BEGIN and EVE_END are the beginning and ending event numbers for which the results will be computed, and EVE_INC is the increment for computing results. After the results have been computed, MOSES places the user in the Disposition Menu so that he can dispose of the data. The corresponding form of the REPORT command is:

     REPORT, REP_NAMES(1), REP_NAME(2),  ... -OPTIONS

Here, REP_NAMES(i) is a set of report names which may be selected and will depend on the command issued. The only option available for reporting is again -EVENTS. The -MAG_DEFINE option defines how the "Magnitude" is computed. You can have one, two or three A(i) and each on must be either X, Y, or Z. If you specify all three (the default) then the magnitudes will be the length of the vectors. Alternatively, the magnitude will be the length of the vector projected on to either a line (if one is specified) or a plane. For example

     -MAG_DEFINE X Y

will give you the length of the vector projected onto the X-Y plane.

The command:


     SENSOR, :DNAME,  -OPTIONS

instructs MOSES to compute the sensor signals of all sensors who's names match :SNAME and there is no DATA for the report command.

MOSES is instructed to compute the draft readings along the draft marks selected by :DNAME with the command:


     DRAFT, :DNAME,  -OPTIONS

and there is no DATA for the report command.

The POINTS command instructs MOSES to compute the location, velocity, motion, and acceleration of the points selected by :PNT_NAME. Here, motion is the vector from the global location of a point the last time the command &DESCRIBE INTEREST was issued to the current position of the point. The form of this command is:


     POINTS, :PNT_NAME,  -OPTIONS

An additional option here is:


     -MAG_DEFINE, A(1), .. A(n)

This defines how the "Magnitude" is computed. You can have one, two or three A(i) and each on must be either X, Y, or Z. If you specify all three (the default) then the magnitudes will be the length of the vectors. Alternatively, the magnitude will be the length of the vector projected on two either a line (if one is specified) or a plane. For example

     -MAG_DEFINE X Y

will give you the length of the vector projected onto the X-Y plane. The available REP_NAMEs available here are: LOCATION, MOTION, HEIGHT, GS, or REL_VELOCITY. The first of these reports the location, velocity, and acceleration of the points. The second reports the location of the points, their motion, the wave elevation at the points, and the clearance between the point and the sea, while the third reports only the height of the points above the waterplane. With a report name of GS, the dynamic "G" loads for the selected points are reported. Finally, the last report gives the wave elevation, the wave clearance, and the wave particle velocity minus the point velocity in global coordinates. If no report name is specified, all reports are produced.

For certain situations, it is desirable to know the location, velocity and acceleration of one point relative to another point. The REL_MOTION command is provided for this, and instructs MOSES to compute the relative location, velocity and acceleration for a pair of points. The results are expressed in the body system of the first point. The form of this command is:


     REL_MOTION, PNT_NAME(1,1), PNT_NAME(2,1), ....  -OPTIONS

The additional option here is:


     -MAG_DEFINE, A(1), .. A(n)

and it has the same meaning as it they did for the POINTS command. There is no DATA for the report command.

The final command here:


     P_MIN_DISTANCE, PIECE, :PNT_SELE, -OPTIONS

reports the minimum distance of from the points selected by :PNT_SELE to the piece PIECE. Here the minimum distance is the smallest of the distance from the vertices of the piece to the points or the distance from the points to the panels perpendicular to the normal of the panel.

Normally one interested in finding whether of not a body "hits something". The reason for using a piece here instead of a body is that this computation can be quite lengthy (goes like the square of the number of panels in the piece). By using an arbitrary piece, you can define a piece that does nothing (zero permeability) and bounds the body for a quick check.