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Analysis of Design

In this section, we will use the analysis toold presented in the main Math-Magik project at https://rblack42/github.io/math-magik to get an estimate of the model weight and center of gravity location.

Material Densities

OpenSCAD will generate a STL file for each part we need to construct to build an actual model. Typically, builders select wood with properties appropriate fpr that part. We need to record the material density for each part so we can calculate the weight and balance data.

Model Weight

THis calculation is simple. A Python program will run OpenSCAD and automatically generate the part STL file. It will then run a mass properties assessment to determine the volume and center of mass for each part. The total weight of the model can be determined by multiplying the part volume by the material density, then summing up the weights of all parts.

Center of Gravity

Locating the center of gravity is more difficult. The mass properties analysis will give us the center of mass for each part. We need to follow the alignment transformations made on that part as it is located in the final model to determine the center of gravity. These alignments are sequential. A rib it aligned within a wing, and the wing is aligned within the model. By placing all positioning data in a separate name_pos.scad file, we can use Python to calculate the final position of the center of mass for a part in the model. The center of gravity calculation can be made using this information.