brompton-computer-guard.scad

   1 // -*- C -*-
   2
   3 cover_ysz = 45;
   4 cover_len = 70;
   5
   6 tube_dia = 21;
   7
   8 attach_cx = -7;
   9 attach_cdy = 0;
  10 attach_w = 25;
  11
  12 attach_inrad = 29;
  13 attach_hole_dist = 5;
  14 attach_hole_dia = 4 + 0.5;
  15 attach_ang = 45;
  16
  17 attach_dz = 2;
  18
  19 comp_dx = 22;
  20 comp_xsz = 45;
  21 comp_zsz = 28;
  22
  23 comp_dy = 5;
  24
  25 comp_slope = 60;
  26
  27 leftend_zsz = 10;
  28 leftend_dz = comp_zsz * 0.6;
  29
  30 min_thick = 4;
  31
  32 rightend_thick = 10;
  33 bolthead_space = 4;
  34
  35 // calculated
  36
  37 cover_lcircle_r = cover_ysz / (1 + 1/sqrt(2));
  38
  39 base_len = cover_len - cover_lcircle_r;
  40
  41 attach_end_r = attach_w/2;
  42
  43 attach_straight_len =
  44   attach_inrad + tube_dia + attach_hole_dist + attach_hole_dia/2
  45   - attach_end_r + attach_hole_dist;
  46
  47 attach_down = tube_dia/2 + attach_dz;
  48
  49 attach_xmax = attach_cx +
  50   cos(attach_ang) * attach_straight_len + attach_end_r;
  51
  52 module RearSideTemplate(){
  53   polygon([[0.1,0],
  54            [-base_len,0],
  55            [-base_len,-cover_ysz],
  56            [0.1,      -cover_ysz]]);
  57   translate([-base_len, -cover_ysz + cover_lcircle_r])
  58     circle(r=cover_lcircle_r);
  59 }
  60
  61 module AttachTemplate(){
  62   hull(){
  63     polygon([[0,   0],
  64              [-0.1, 0],
  65              [-0.1, -cover_ysz],
  66              [0,    -cover_ysz]]);
  67     translate([attach_cx, -attach_cdy]) rotate([0,0,-attach_ang]) {
  68       polygon([[-attach_cx,          attach_w/2],
  69                [0,                   -attach_w/2],
  70                [attach_straight_len, -attach_w/2],
  71                [attach_straight_len, attach_w/2]]);
  72       translate([attach_straight_len, 0])
  73         circle(r=attach_end_r);
  74     }
  75   }
  76 }
  77
  78 module AttachElevation(anddown){
  79   hull(){
  80     translate([-cover_len - 0.5, leftend_dz - leftend_zsz/2])
  81       square([1, leftend_zsz]);
  82     translate([-comp_dx - comp_xsz/2, -0.1])
  83       square([comp_xsz, comp_zsz + min_thick]);
  84     translate([attach_xmax, 0])
  85       square([1, rightend_thick + bolthead_space]);
  86   }
  87   if (anddown)
  88     translate([-comp_dx, -attach_down-5])
  89       square([comp_dx + attach_xmax+2, attach_down+6]);
  90 }
  91
  92 module AttachElevationSelector(anddown) {
  93   translate([0,100,0]) rotate([90,0,0]) linear_extrude(height=200)
  94     AttachElevation(anddown);
  95 }
  96
  97 module BodyPositive(){
  98   intersection(){
  99     linear_extrude(height=60) RearSideTemplate();
 100     AttachElevationSelector(false);
 101   }
 102   intersection(){
 103     translate([0,0,-attach_down]) linear_extrude(height=100) AttachTemplate();
 104     AttachElevationSelector(true);
 105   }
 106 }
 107
 108 module Cutouts(){
 109   Tube();
 110   Bolts();
 111   Computer();
 112 }
 113
 114 module Body(){
 115   difference(){
 116     intersection(){
 117       BodyPositive();
 118       translate([-100,-200,-100]) cube([200,200,200]);
 119     }
 120     Cutouts();
 121   }
 122 }
 123
 124 module Computer(){
 125   multmatrix([[1,0,0,0],
 126               [0,1, tan(90-comp_slope), 0],
 127               [0,0,1,0],
 128               [0,0,0,1]])
 129   translate([-comp_dx - comp_xsz/2, -cover_ysz + comp_dy, -50])
 130     cube([comp_xsz, 100, comp_zsz + 50]);
 131 }
 132
 133 module Tube(){
 134   translate([attach_cx, -attach_cdy, -tube_dia/2 - 0.1 - attach_dz]) {
 135     rotate_extrude(convexity=10) {
 136       translate([attach_inrad + tube_dia/2, 0])
 137         circle(r=tube_dia/2);
 138     }
 139   }
 140 }
 141
 142 module Bolt(){
 143   translate([0,0,-50]) linear_extrude(height=80) {
 144     circle(r=attach_hole_dia/2, $fn=20);
 145   }
 146   translate([0,0,rightend_thick]) linear_extrude(height=80) {
 147     circle(r=attach_hole_dia/2 * 2, $fn=20);
 148   }
 149 }
 150
 151 module Bolts(){
 152   translate([attach_cx, -attach_cdy]) rotate([0,0,-attach_ang]) {
 153     translate([attach_inrad - attach_hole_dist - attach_hole_dia/2, 0])
 154       Bolt();
 155     translate([attach_inrad + tube_dia
 156                +attach_hole_dist + attach_hole_dia/2, 0])
 157       Bolt();
 158   }
 159 }
 160
 161 module Demo(){
 162   Cutouts();
 163   %BodyPositive();
 164 }
 165
 166 module Print(){
 167   rotate([-90,00])
 168     Body();
 169 }
 170
 171 //Demo();
 172 //Body();
 173 Print();