Page tree
Skip to end of metadata
Go to start of metadata

1    Total mass calculation

Now that the whole ship itself is in place, you are ready for some analysis functionality.

In entity Mass calculation, the mass and the centre of gravity of the whole system will be calculated. These values will depend on the mass and centre of gravity of both light ship weight and cargo objects. The total mass is calculated by the summation of all mass components (entities) one level below entity Mass calculation. The centre of gravity of a system of components is defined as the average of their positions, weighted by their masses.

  • Include entities Light Ship Weight and Mass Cargoes as children of Mass calculation. Both are singular obligatory entities.
  • Create the following parameters in the Knowledge Browser:

Parameter name

Dimension

Determined by

Reference

In Class

Mass

[t]

USR: User or system/equation

Mass

Mass calculation

COGX

[m]

USR: User or system/equation

Centre of gravity in X direction

Dimensions

COGY

[m]

USR: User or system/equation

Centre of gravity in Y direction

Dimensions

COGZ

[m]

USR: User or system/equation

Centre of gravity in Z direction

Dimensions

MOMX

[t*m]

USR: User or system/equation

Moment around X-axis

Dimensions

MOMY

[t*m]

USR: User or system/equation

Moment around Y-axis

Dimensions

MOMZ

[t*m]

USR: User or system/equation

Moment around Z-axis

Dimensions

 

  • Include the following parameters in entity Mass calculation: Mass, COGX, COGY, COGZ, MOMX, MOMY, MOMZ and QEntityRef.
  • Create the following relations in the Knowledge Browser and connect them to the pertaining parameters in entity Mass calculation.

Mass = SUM(@QEntity, 1, @Mass) (The result will be the summation of all parameters Mass of the entities one level below.)

COGX = MOMX/Mass

COGY = MOMY/Mass

COGZ = MOMZ/Mass

MOMX = SUM(@QEntity, 1, @MOMX)

MOMY = SUM(@QEntity, 1, @MOMY)

MOMZ = SUM(@QEntity, 1, @MOMZ)

  • To show computed values set attribute @SHOW on QEntityData.
  • Assign the following text to QEntityRef: “Mass calculation: summation of light ship weight and total cargo weight”.

Please note, that you just created 'normal' relations and connected these to the parameters in the entity, because these are going to be used in several Mass entities.

2     Light Ship Weight

  • Include the entities: Mass Hull, Mass Decks and Mass Bulkheads as children of Light Ship Weight. All three are singular obligatory.
  • Include the following parameters in entity Light Ship Weight: Mass, COGX, COGY, COGZ, MOMX, MOMY, and MOMZ.
  • Connect the same relations as above from the Knowledge Browser to the pertaining parameters in entity Light Ship Weight.
  • To show computed values set attribute @SHOW on QEntityData.

Mass Hull

  • Create the following parameter in the Knowledge Browser:

Parameter name

Dimension

Determined by

Reference

In Class

Weight_volume_factor

[t/m^3]

USR: User or system/equation

Weight factor per volume

Mass calculation

 

  • Include the following parameters in entity Mass Hull: Mass, COGX, COGY, COGZ, MOMX, MOMY, MOMZ, Volume and Weight_volume_factor.
  • Create the following relations in entity Mass Hull (here, 12 is the entity ID of Main Dimensions, change this for your case):

Mass = Weight_volume_factor*Volume

COGX = (ENTITY#(12).Lpp)*0.5 (assume the centre of gravity of the hull in X direction half of the ship length)

COGY = 0 (amidships)

COGZ = (ENTITY#(12).Dm)*0.45 (assume the centre of gravity of the hull in Z direction at 45 % of the moulded depth)

MOMX = COGX*Mass

MOMY = COGY*Mass

MOMZ = COGZ*Mass

  • To show computed values set attribute @SHOW on QEntityData.
  • Make parameter Volume in entity Mass Hull use local properties ("Instantiate") and remove @MODIFY because you do not want to allow modification here.
  • Create the following relation in entity Mass Hull (here, 13 is the entity ID of Hydrostatics, change this for your case):

Volume = ENTITY#(13).Volume

Mass Decks

  • Include the singular obligatory entity Decks as child of entity Mass Decks.
  • Include the following parameters in entity Mass Decks: Mass, COGX, COGY, COGZ, MOMX, MOMY, and MOMZ.
  • Connect the following relations in the Knowledge Browser to the pertaining parameters in entity Mass Decks (This is again the same list as at the top of this page):

Mass = SUM(@QEntity, 1, @Mass)

COGX = MOMX/Mass

COGY = MOMY/Mass

COGZ = MOMZ/Mass

MOMX = SUM(@QEntity, 1, @MOMX)

MOMY = SUM(@QEntity, 1, @MOMY)

MOMZ = SUM(@QEntity, 1, @MOMZ)

  • To show computed values set attribute @SHOW on QEntityData.

In entity Decks, below entity Mass Decks, you can present a table that contains a copy of parameters (Name$ and Area) of all decks that are defined by the user in entity Decks below Lay out. In addition, the centre of gravity and mass of each deck can be calculated here.

  • Include the following parameters in entity Decks below Mass Decks: Name$, Nr, Area, Mass, COGX, COGY, COGZ, MOMX, MOMY, MOMZ and Weight_area_factor.
  • With exception of parameter Nr, put all parameters in the table view (localize (instantiate) parameter and provide attribute @MULTVAL in its Data Slot).

After the first parameter has been put in the table view with the attribute @MULTVAL, you can drag the other needed parameters directly to the table view from the Knowledge Browser.

The number of cases is equal to the number of defined decks by the user in the “Lay out” Entity. We are going to get this information.

  • Create the following relation in entity Mass Decks->Decks (here, 10 is the entity ID of Layout->Decks)

Nr = ENTITY#(10).Nr

The first column/case of the table should contain data (Name$ and Area) from the first defined Deck in entity DeckThe second column contains data from the second defined deck, etc.

  • This can be done by the following relations in entity Mass Decks->Decks (here, 16 is the entity ID of Layout->Decks->Deck)

Name$ = ENTITY#(16, ORCA(1)).Name$

Area = ENTITY#(16, ORCA(1)).Area

When you want refer to a multiple entity, you also have to indicate the QEntityIndex. Quaestor automatically provides an index value in the Quaestor parameter QEntityIndex for each multiple entity. So ENTITY#(xx, 3) refers to the third defined entity Deck. The function ORCA(1) returns the current case number which is now being executed. So for the second column/case in a table, the value of ORCA(1) = 2. When we combine the index with the ORCA() function, like in the Area relation above, the second column of the current table will refer to the area from the second defined deck, etc.

  • Add the following relations in entity Mass Decks->Decks (here, 16 is the entity ID of Layout->Decks->Deck):

COGX = ENTITY#(16, ORCA(1.X_front) + (ENTITY#(16, ORCA(1)).X_aft))/2

COGY = 0

COGZ = ENTITY#(16, ORCA(1)).Z

MOMX = COGX*Mass

MOMY = COGY*Mass

MOMZ = COGZ*Mass

Mass = Weight_area_factor*Area

  • To show computed values set attribute @SHOW on QEntityData.

As already discussed in the Deck entity, the Weight_area_factor is a bit special. What you want is, that this property is connected to the original value in Deck (of which the value is hidden) but, when modified by the user, the modified value should be used in both the present Mass Decks->Decks entity AND the original entity Decks->Deck. This is done by means of the @SAVEINSOURCE attribute.

  • Create the following relation:

Weight_area_factor = ENTITY#(16, ORCA(1)).Weight_area_factor

  • And add the following attributes to the localized Weight_area_factor parameter:

@MULTVAL
@MODIFY
@SAVEINSOURCE

 

When a user adds or removes a deck, or changes values of an existing defined deck, these adaptations will automatically propagated to the Mass Decks entity.

Mass Bulkheads

  • Include the singular obligatory entity Bulkheads as child of entity Mass Bulkheads.
  • Include the following parameters in entity Mass Bulkheads: Mass, COGX, COGY, COGZ, MOMX, MOMY, and MOMZ.
  • Connect the following relations in the Knowledge Browser to the pertaining parameters in entity Mass Bulkheads (This is again the same list as at the top of this page):

Mass = SUM(@QEntity, 1, @Mass)

COGX = MOMX/Mass

COGY = MOMY/Mass

COGZ = MOMZ/Mass

MOMX = SUM(@QEntity, 1, @MOMX)

MOMY = SUM(@QEntity, 1, @MOMY)

MOMZ = SUM(@QEntity, 1, @MOMZ)

  • To show computed values set attribute @SHOW on QEntityData.
  • Include the following parameters in entity Bulkheads below Mass Bulkheads: Name$, Nr, Area, Mass, COGX, COGY, COGZ, MOMX, MOMY, MOMZ and Weight_area_factor.
  • With exception of parameter Nr, put all parameters in the table view (localize (instantiate) parameter and provide attribute @MULTVAL in its Data Slot).
  • Make the same kind of relations in Mass Bulheads->Bulkheads as in Mass Decks->Decks above (here, 17 refers to Layout->Bulkheads->Bulkheads):

Nr = ENTITY#(17).Nr

Area = ENTITY#(17).Area.ORCA(1)

Name$ = ENTITY#(17).Name$.ORCA(1) TODO: dit levert een foutmelding in Quaestor

COGX = ENTITY#(17).X.ORCA(1)

COGY = 0

COGZ = (ENTITY#(17).Z_bottom.ORCA(1) + ENTITY#(17).Z_top.ORCA(1))/2

MOMX = COGX*Mass

MOMY = COGY*Mass

MOMZ = COGZ*Mass

Mass = Weight_area_factor*Area

Weight_area_factor = ENTITY#(17).Weight_area_factor.ORCA(1)

  • And add the following attributes to the localized Weight_area_factor parameter:

@MULTVAL
@MODIFY
@SAVEINSOURCE

  • To show computed values during a dialogue write “@SHOW” behind “QEntityData”

Please note the difference with the previous section, in which a table was created referring to values within multiple entities. For the bulkheads we have created one table and refer to values within the table of another singular Entity!


3    Mass Cargoes

  • Include the singular obligatory entity Cargoes as child of entity Mass Cargoes.
  • Include the following parameters in entity Mass Cargoes: Mass, COGX, COGY, COGZ, MOMX, MOMY, MOMZ and QEntityRef.
  • Connect the same relations as mentioned at the top of the page from the Knowledge Browser to the pertaining parameters in entity Mass Cargoes.
  • To show computed values set attribute @SHOW on QEntityData.
  • Assign the following value to QEntityRef: “Cargo mass calculation: summation of all cargo components”.
  • Include the following parameters in entity Cargoes below Mass Cargoes: Name$, Nr, Mass, COGX, COGY, COGZ, MOMX, MOMY, MOMZ, QEntityDoc and QEntityRef.
  • With exception of parameter Nr, put all parameters in the table view (localize (instantiate) parameter and provide attribute @MULTVAL in its Data Slot).

In entity Cargoes you will enable the user to create a table with a number of cargo objects. For each object, the user has to provide a name, COG and mass.

  • Create the following relations:

MOMX = COGX*Mass

MOMY = COGY*Mass

MOMZ = COGZ*Mass

  • To show computed values set attribute @SHOW on QEntityData.
  • Assign the following value to QEntityRef: “Define name, mass and COG of cargo objects”

As explanation to the user, you can include a schematic picture that depicts the used coordinate system within this configurator.

  • Right-click on QEntityDoc in entity Cargoes and select Taxonomy->Include Binary Data or press Ctrl+B. Now you can browse to the file you want to include: “coordinate_system.bmp”.

 


Back to content | << PreviousNext >>

  • No labels