Georges,
If this is to be an explicit Pro/E,CreoElementsPro,Creo exercise you will need to back into the solution somewhat. The basics will be as follows:
Model the entire assembly and floats with all material properties correctly specified.
Caluculate the weight and volume of the entire assembly using Mass Props. This will give you a baseline of volumetric displacement of the entire assembly. I.E. if you entire assembly was submerged. This gives you the constant for your math later on.
Create an closed internal surface within each float.
Create a parametric"feature" that simulates the volume you wish to add. I.E. the water level.
Create an assembly with features that you can drive height dimensions of each float relative the water's surface. I.E. your assembly floating on the water.
You know the weight of water or what ever material you are going to fill the floats with. Use the volume of each float's enclosed quilt and create relations to calculate the displacement (bouyancy) each float and their individual impacts on the assembly itself. For example, if you have four floats and you fill three with 40 gallons of water and the fourth with 10 gallons then the structure will tip away from the 10 gallon floatand equalize against (list toward)the bouyancy of the three with 40 gallons.
Create relations/calculations that will give the net effect of the bouyancy vs. the weight of the assembly and apply those results to the height dimensions in the assembly that will simulate the structure floating on the water given the volume of water added to the floats.
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That's the basic idea. You have a bit of math to do. Make sure that you do not create circular references within Pro as the values will not result in a correct solution. You may have to use Excel to pass values back and forth to create the resultsand effects thenimport the valuesand regen the assembly.
have fun.
