A lot more work on the Microcar design. I'm not yet at all satisfied with this.

microcar/microcar.scad

@@ -0,0 +1,20 @@
+/**
+ * microcar.scad
+ *
+ * First sketch of a microcar.
+ */
+
+include <BOSL2/std.scad>
+  
+include <suspension.scad>
+include <tub.scad>
+
+
+tub(fl=1100);
+
+translate([-900,0,130])
+    suspension();
+
+translate([1100,0,130])
+    suspension();
+

microcar/shockabsorber.scad

@@ -0,0 +1,40 @@
+/**
+ * shockabsorber.scad
+ *
+ * First sketch of a microcar spring/shock absorber unit. Ideally I
+ * would want to use linked hydropneumatic units, but that would be
+ * *absurdly* over expensive for a one off prototype. Air or conventional
+ * spring units would be far more pragmatic.
+ */
+
+include <BOSL2/std.scad>
+
+eye_inner_diameter = 25/3; // to make it the same as pivot_radius defined
+                            // in suspension.scad
+
+module eye( eid=eye_inner_diameter) {
+    rotate([0, 90, 0]) {
+        difference() {
+            cylinder( h=eid, r=eid, center=true);
+            cylinder( h=2*eid, d=eid, center=true);
+        }
+    }
+}
+
+module shockabsorber( length=150, eid=eye_inner_diameter, coil_over=true) {
+    short_length=length-(eid*4);
+    
+    translate([0,0,eid]) {
+        // cylinder
+        cylinder(h=short_length/2, r=short_length/16);
+        // rod
+        cylinder(h=short_length, r=short_length/32);
+        
+        translate([0,0,0-eid]) {
+            eye(eid);
+        }
+        translate([0,0, short_length+eid]) {
+            eye(eid);
+        }
+    }
+}

microcar/suspension.scad

@@ -5,49 +5,76 @@
  *
  * The purpose of the subframe is sumply to carry the inner ends of the
  * wishbones, so it is simply the minimum size required to do that.
+ *
+ * TODO: this does not yet consider caster, camber, anti-dive geometry,
+ * or other such niceties.
  */
+
+include <BOSL2/std.scad>
+include <shockabsorber.scad>
+include <wheel.scad>
  
- // assumes we're building out of square section aluminium tobe;
- // the section width of that tube.
- stock_section = 25;
+// assumes we're building out of square section aluminium tobe;
+// the section width of that tube.
+stock_section = 25;
  
- lug_thickness = stock_section/6;
+lug_thickness = stock_section/6;
  
- // radius of suspension pivots
- pivot_radius = stock_section/3; //for now
+// radius of suspension pivots
+pivot_radius = stock_section/3; //for now
  
- module lug() {
+module lug() {
     difference() {
-         union() {
-             translate([0, stock_section/2, 0]){
-                cube([ stock_section, stock_section, lug_thickness], center=true);
-             }
+        union() {
+            translate([0, stock_section/2, 0]){
+                cube([ stock_section, stock_section, lug_thickness],
+                    center=true);
+            }
              
-             cylinder( r=stock_section/2, h=stock_section/4, center=true);
-                 
+            cylinder( r=stock_section/2, h=stock_section/4, 
+                center=true);      
          }
          cylinder( r=pivot_radius, h=stock_section, center=true);
-     }
+    }
 }
  
- module wishbone(l, w) {
-     ssd2 = stock_section/2;
-     ssm2 = stock_section * 2;
-     ssm3 = stock_section * 3;
+module wishbone(l, w, is_upper = true) {
+    ssd2 = stock_section/2;
+    ssm2 = stock_section * 2;
+    ssm3 = stock_section * 3;
      
-     translate([ (l - lug_thickness)/2, stock_section, ssd2])
-         rotate([180,90,0])
+    // wishbone inboard pivot lugs
+    translate([ (l - lug_thickness)/2, stock_section, ssd2])
+        rotate([180,90,0])
             lug();
-     translate([ 0 - (l - lug_thickness)/2, stock_section, ssd2])
-         rotate([180,90,0])
+    translate([ 0 - (l - lug_thickness)/2, stock_section, ssd2])
+        rotate([180,90,0])
             lug();
      
-     color("silver")
-     union() {
-         intersection(){
-             linear_extrude(stock_section)
+    // shock absorber end lugs
+    if (is_upper) {
+        translate([ ssd2, ssm2, ssd2])
+            rotate([180,90,0])
+                lug();
+        translate([ -ssd2, ssm2, ssd2])
+            rotate([180,90,0])
+                lug();
+    } else {
+        translate([ ssd2, w-ssm3, ssd2])
+            rotate([180,90,180])
+                lug();
+        translate([ -ssd2, w-ssm3, ssd2])
+            rotate([180,90,180])
+                lug();
+    }
+     
+    color("silver")
+    union() {
+        intersection(){
+            linear_extrude(stock_section)
                 polygon( points=[[0-(l/2), ssd2], [l/2, ssd2],
-                        [3*ssd2, w-(3*ssd2)], [0-(3*ssd2), w-(3*ssd2)],
+                        [3*ssd2, w-(3*ssd2)], 
+                        [0-(3*ssd2), w-(3*ssd2)],
                         // hole in the middle
                         [0-(l/2 - 3*ssd2), 3*ssd2],
                         [l/2 - 3*ssd2, 3*ssd2],
@@ -55,10 +82,10 @@
                     paths=[[0, 1, 2, 3], [4, 5, 6, 7]]);
             translate([0 - (l - ssd2)/2, 0, 0 - stock_section])
                 cube([l-ssd2, w, ssm3]);
-         }
-         translate([-3*ssd2, w-3*ssd2, 0])
+        }
+        translate([-3*ssd2, w-3*ssd2, 0])
             cube( [stock_section, 3*ssd2, stock_section]);
-         translate([ssd2, w-3*ssd2, 0])
+        translate([ssd2, w-3*ssd2, 0])
             cube( [stock_section, 3*ssd2, stock_section]);
     };
     color("darkgray")
@@ -83,27 +110,45 @@
      }
  }
  
- module suspension( l = 300, w = 300, h = 300,
+module suspension( l = 300, w = 300, h = 300,
         track = 1400, hub_width = 135, wheel_diameter=600) {
-     subframe(l,w,h);
+    subframe(l,w,h);
+            
+    wishbone_length = 500; // TODO: calculate
      
-     // Upper wishbones
-     translate([0, w/2, (h/2) - stock_section])
-        wishbone( l, 500);
-     mirror([0,1, 0]) {
-         translate([0, w/2, (h/2) - stock_section])
-            wishbone( l, 500);
-     }
+    // Upper wishbones
+    translate([0, w/2, (h/2) - stock_section])
+        wishbone( l, wishbone_length);
+    mirror([0,1, 0]) {
+        translate([0, w/2, (h/2) - stock_section])
+            wishbone( l, wishbone_length);
+    }
 
-      // lower wishbones
-     translate([0, w/2, 0 -(h/2)])
-        wishbone( l, 500);
-     mirror([0,1, 0]) {
-         translate([0, w/2, 0 -(h/2)])
-            wishbone( l, 500);
-     }
- }
+    shock_extent = wishbone_length - (5.5 * stock_section);
+    shock_angle = atan(shock_extent/(h-stock_section));
+    shock_length = shock_extent * tan(shock_angle);
+
+    // lower wishbones
+    translate([0, w/2, 0 -(h/2)]) {
+        wishbone( l, wishbone_length, false);
+        translate([0, wishbone_length + 75, stock_section])
+            wheel();
+        translate([0, (stock_section*2), h-(stock_section/2)])
+            rotate([shock_angle +180, 0, 0])
+                shockabsorber(length=shock_length,eid=stock_section/2);
+    }
+    mirror([0,1, 0]) {
+        translate([0, w/2, 0 -(h/2)]) {
+            wishbone( l, wishbone_length, false);
+            translate([0, wishbone_length + 75, stock_section])
+                wheel();
+            translate([0, (stock_section*2), h-(stock_section/2)])
+                rotate([shock_angle +180, 0, 0])
+                    shockabsorber(length=shock_length,
+                    eid=stock_section/2);
+        }
+    }
+}
  
- lug();
- 
-suspension();
+  
+// suspension();

microcar/tub.scad

@@ -1,3 +1,11 @@
+/**
+ * tub.scad
+ *
+ * The tub of a microcar.
+ */
+
+include <BOSL2/std.scad>
+
 $fn = $preview ? 32 : 256;
 
 a_pillar_y = -400;  // y location of face of 'A' pillar
@@ -28,7 +36,7 @@ floor_width = 1500;
 // angle of the front bulkhead to vertical
 layback_angle_f = 30;
 // angle of the rear bulkhead to vertical
-layback_angle_r = 45;
+layback_angle_r = 50;
 
 sheet_thickness = 8;
 sill_max_height = bb_height;
@@ -84,7 +92,7 @@ module sill( floor_length = 1100) {
             }
         rotate([-3, 0, 0])
             translate([0, cr - (sill_width/2), 0])
-                cylinder( h = cowl_height, 
+                cylinder( h = cowl_height,
                 r = cr);
     }
 }
@@ -100,17 +108,23 @@ module front_bulkhead() {
 module rear_bulkhead() {
 }
     
+module tub(fl=floor_length, fw=floor_width, st=sheet_thickness,
+        sw=sill_width) {
+    cube([fl, fw, st],
+            center=true);
+    battery_box();
 
-cube([floor_length, floor_width, sheet_thickness],
-        center=true);
-battery_box();
-
-translate([0, ( floor_width/2) + (sill_width/2), 0])
-    sill();
-
-mirror([0, 1, 0])
-    translate([0, 
-        ( floor_width/2) + (sill_width/2), 0])
+    translate([0, ( fw/2) + (sw/2), 0])
         sill();
 
-front_bulkhead();
+    mirror([0, 1, 0])
+        translate([0, 
+            ( fw/2) + (sw/2), 0])
+            sill();
+
+    front_bulkhead();
+        
+    rear_bulkhead();
+}
+
+// tub();

microcar/wheel.scad

@@ -0,0 +1 @@
+../model/wheel.scad