Week 2: computer-aided design

Consistently with what I mentionned here, I like OpenSCAD.

My first creation was obviously a molecule (before I learned VMD could directly output STL files...).

 
$fs=0.05;
for ( i = [0:5] ) {
  rotate( i*360/6, [1, 0, 0])
   {
   color("royalblue") { 
   translate( [0, 10, 0] ) sphere(r = 4);
   rotate (30, [1, 0, 0]) translate( [0, 9, 0] ) cylinder (r=2,h=5,center=true);
   translate( [0, 15, 0] ) rotate(90, [1,0,0]) cylinder(r=2,h=10,center=true);
   }
   color("white")  translate( [0, 20, 0] ) sphere(r = 3);
   } 
}	
	

A more complex example.

/*
Parametres de l'aerorefrigerant
*/
z0=40;
a=0.005;
re=12;
e=0.6;
ri=re-e;	

/*
Fond
*/
color("forestgreen") cube([100,100,1]);

/*
batiment reacteur 
*/
translate([70,80,1])
{
color("lightgray") 
union() {
	cylinder(r=10.2,h=13);
	translate([0,0,2])
	difference() {
		sphere(r=15);
		translate([0,0,-5])
		cube([32,32,32],center=true);
	}
}
translate([7,-7.5,0])
color("lightgray") cube([20,15,10]);

}
translate([21,21,1.1]) color("lightgray") {
union() {
	for(i=[0:50]) {
	    translate([0,0,i])
	/*    rotate_extrude(convexity = 10)
	    translate([8+0.015*(i-34)*(i-34), 0, 0])
	    circle(r = 1);
	*/
		difference() {
	    		cylinder(r1=re+a*(i-z0)*(i-z0),r2=re+a*(i+1-z0)*(i+1-z0),1);
			translate([0,0,-0.2])
			cylinder(r1=ri+a*(i-z0)*(i-z0),r2=ri+a*(i+1-z0)*(i+1-z0),1.4);
		}
	}
}
/*
	difference() {
		cylinder(r=10,25);
		cylinder(r=8,30);
	}
*/
}
	

Even more complex, to illustrate further OpenSCAD strenghts, here is a very impressive and very funny project: the digital sundial by Mojoptix. It's great !

I also tried SolidWorks. I'll give a try to OneShape.

For kids, I would recommend 3DSlash: it is a Minecraft-style CAD software, developped for the younger makers. It's really easy to use, and has many nice features like picture superposition to draw an object directly from a silhouette. It also works on tablets.