Add first prototype

This is just the basic shape without modularity (yet).

diff --git a/skeleton_cell.scad b/skeleton_cell.scad
new file mode 100644 (file)
index 0000000..0aaa82a
--- /dev/null
+++ b/skeleton_cell.scad
@@ -0,0 +1,80 @@
+fit_clearance = 0.5;
+
+width = 50;
+height = 50;
+depth = 100;
+
+thickness = 2;
+
+ring_height = thickness;
+ring_pos = thickness;
+
+ring_clearance = ring_height + ring_pos;
+ring_thickness = thickness / 2;
+
+module face(width, height, thickness, ring_clearance)
+{
+       linear_extrude(thickness)
+               difference()
+               {
+                       square([width, height], center = true);
+                       square([width - 2 * thickness, height - 2 * thickness], center = true);
+                       translate([0, - (height / 2 - ring_clearance / 2)])
+                               square([width, ring_clearance], center = true);
+               };
+       translate([0, - (height / 2 - (ring_clearance + thickness) / 2), ring_thickness])
+               linear_extrude(thickness - ring_thickness)
+                       difference()
+                       {
+                               square([width - 2 * ring_thickness, ring_clearance + thickness], center = true);
+                               translate([0, thickness / 2])
+                                       square([width - 2 * thickness, ring_clearance], center = true);
+                       };
+}
+
+module ring(width, depth, ring_thickness, ring_height)
+{
+       linear_extrude(ring_height)
+               difference()
+               {
+                       square([width, depth], center=true);
+                       square([width - 2 * ring_thickness, depth - 2 * ring_thickness], center = true);
+               };
+}
+
+module rail(depth, thickness)
+{
+       linear_extrude(depth)
+               polygon([[0, 0], [0, thickness], [thickness, 0]]);
+}
+
+module rails(dims, thickness, fit_clearance)
+{
+       translate([dims.x / 2, dims.y / 2])
+               mirror([1, 1, 0])
+               rail(dims.z - thickness, thickness - fit_clearance);
+       translate([- (dims.x / 2 - thickness), - (dims.y / 2 - thickness)])
+               mirror([1, 1, 0])
+               rail(dims.z - thickness, thickness - fit_clearance);
+       translate([dims.x / 2, - dims.y / 2])
+               mirror([1, 0, 0])
+               rail(dims.z - thickness, thickness - fit_clearance);
+       translate([- (dims.x / 2 - thickness), dims.y / 2 - thickness])
+               mirror([1, 0, 0])
+               rail(dims.z - thickness, thickness - fit_clearance);
+}
+
+module half_cage()
+{
+       face(width, height, thickness, ring_clearance);
+       translate([0, ring_clearance / 2, thickness])
+               rails([width, height - ring_clearance, depth - thickness], thickness, fit_clearance);
+}
+
+half_cage();
+translate([0, 0, depth])
+       rotate(180, [0, 1, 0])
+               half_cage();
+translate([0, - (height / 2 - ring_clearance + fit_clearance / 2), depth / 2])
+       rotate(90, [1, 0, 0])
+               ring(width, depth, ring_thickness - fit_clearance, ring_height - fit_clearance);