Propeller, Repeller, Wings - construction kit

thingiverse

It appears you've shared a detailed explanation of a propeller design process using OpenSCAD, involving various functions and libraries. I'll summarize the key points to ensure understanding: 1. **gendata() Function:** * This function generates airfoil slices based on a given description format. * It uses a loop to iterate over each slice in the description matrix \(M\). * For each slice, it applies transformations (rotation, translation) using the \(T\), \(R\), and \(Tx\) functions from the NACA\_sweep library. 2. **sweep() Function:** * This function skins a sequence of polygons into a 3D object. * It expects each polygon to have the same number of points and not self-intersect or intersect with other polygons. * The call for this function is straightforward, taking the output of gendata() as input. 3. **nSpline() Function:** * This function performs multi-dimensional interpolation using splines. * It operates over the description format and expands it to any desired refinement. * The call involves specifying the number of slices to be interpolated and the desired refinement level. To implement this propeller design, follow these steps: 1. Prepare your airfoil data in a suitable format for OpenSCAD. 2. Create a description matrix \(M\) that outlines the shape of each slice in the propeller. 3. Use the gendata() function to generate polygons for each slice based on this description. 4. Apply transformations using the T, R, and Tx functions from the NACA\_sweep library to position these slices correctly. 5. Feed the output of gendata() into the sweep() function to create the propeller shape. 6. Optionally, use the nSpline() function for interpolation to achieve a more refined design. This process should allow you to create complex organic shapes like boat propellers using OpenSCAD.