LitioLAB Projects - Case studies

Check how you can draw complex engineering or architectural shapes in AutoCAD/GStarCAD with LitioLAB

LitioLAB Project Files (.LLP) are a type of file that LitioLAB uses to store, retrieve, and share LitioLAB project information.

It stores data like input variable data, parameter range and mathematical formula contents.

We are adding information permanently. Users are also invited to share projects!

How to draw airfoils
How to draw a catenary curve - a hanging-cable shape
How to draw a Wankel engine housing
How to draw a spur (involute) gear profile
Equation of time - How to draw a sundial correction curve;
it can be extrapolated to the design of machine CAMS
How to draw oblique throw trajectories
How to draw beam-deflection shapes with LitioLAB

How to draw NACA (and other) airfoils

An airfoil can be defined as a pair of parametric equations for X and Y, for the formula parameter varying from 0.0 to 2*PI. Check the RATIONALE here OR here.

We can rewrite these formulas into a calculator-like form, as follows.

X = f = 0.5+0.5*(abs(cos(r2d(u))))^c1/cos(r2d(u))

Y = g = 0.1277*0.5*(abs(sin(r2d(u))))^c1/sin(r2d(u))*(1-f ^j1) + j2*sin(r2d(pi*f ^c2)) + sin(r2d(f*2*pi))*0.0

Here, I have already replaced some of the formula coefficients and parameters, with the name of an auxiliary parameter, either constant or formula (that works as constant in this case), as shown on the video, and as follows:

It is clear, that there will be an issue due to the dividing cos(u) and sin(u), that turn into 0 within the range of use of the formula, creating a division by zero error.

This can be easily solved, if instead of u limits being 0.0 and 2*PI, we make them a little more than 0.0 and a little less than 2*PI, AND by skipping the u = PI value, by considering an odd number of divisions of this parameter u.

So, for our first example, the NACA5412 Arfoil, after inputting all the parameters, we get its drawing.

NACA5412

We repeat the process for some more examples, as follows:

Clark Y

Ag 24

flying wing profile