digispark-with-cable.scad

   1 // -*- C -*-
   2
   3 include <utils.scad>
   4
   5 //tongue_w = 11.92 + 0.4;
   6
   7 usb_w = 12.01 + 0.19;
   8 usb_wall_w = 0.51;
   9 usb_tongue_d = 8.97 - 0.2;
  10 usb_tongue_w_slop = +0.5;
  11 usb_wall_h = 4.54 - 2.04;
  12 usb_ceil_th = 0.425;
  13
  14 side_wall_th = 1.5; // XXXX rename wall_th
  15
  16 board_l = 17.56 + 0.2;
  17 board_w = 19.14 + 0.2;
  18 board_th = 1.92 + 0.1;
  19
  20 sw_to_edge = board_w/2 + 0.1;
  21
  22 front_wall_th = 0.75;
  23 // egress_w = 8.0;
  24
  25 wall_y_min = -board_l - side_wall_th; // XXXX remove
  26 ceil_y_min = wall_y_min - 5;;
  27
  28 small_walls = [
  29                [ [0, 0], [-sw_to_edge, -1.0] ],
  30                [ [sw_to_edge-4.5, -4.5], [sw_to_edge, -5.7] ],
  31 //             [ [3.0, -11.72],              [sw_to_edge, -13.38] ],
  32                [ [-sw_to_edge+3.85, -14.90], [sw_to_edge, -13.38] ],
  33                ];
  34 chip_cutout = [[ -sw_to_edge + 4.20,    -3.75 ],
  35                [ -sw_to_edge + 11.95,  -11.90 ]];
  36
  37 strain_w = 2.0 + 0.5;
  38 strain_t = 1.0 + 0.5;
  39 strain_pitch_across = 5;
  40 strain_pitch_along = 10;
  41 strain_groove_d = 2;
  42 strain_groove_w = 3;
  43
  44 cover_strap_c_d_y = 5.5; // from front of board
  45 cover_registration_sz_y = 2;
  46 cover_registration_sz_z = 3;
  47
  48 cable_space_z = 6;
  49 cable_dia = 5;
  50 bottom_floor_th = 1.5;
  51
  52 fit_gap_z = 0.5;
  53 fit_gap_y = 0.25;
  54 side_x_gap = 0.5;
  55
  56 cover_ceil_th = 0.9;
  57
  58 // calculated
  59
  60 strap_w = strain_w;
  61 strap_cutout_x = side_wall_th * 2;
  62 strap_cutout_z = side_wall_th;
  63
  64 top_top_z = usb_wall_h;
  65 top_base_z = -board_th;
  66 bottom_base_z = top_base_z - cable_space_z - bottom_floor_th;;
  67
  68 front_y_max = front_wall_th;
  69 main_y_min = -board_l - side_wall_th;
  70
  71 strain_0_y_c = main_y_min - strain_w/2;
  72 strain_1_y_c = strain_0_y_c - strain_pitch_along;
  73 total_y_min = strain_1_y_c - strain_w/2 - side_wall_th;
  74
  75 bottom_wall_top_z = (top_top_z + top_base_z) * 0.5 - fit_gap_z/2;
  76 cover_wall_bot_z  = (top_top_z + top_base_z) * 0.5 + fit_gap_z/2;
  77 cover_top_z  = top_top_z + cover_ceil_th;
  78
  79 top_side_wall_x = +board_w/2 + side_wall_th;
  80 total_side_wall_x = top_side_wall_x + side_wall_th + side_x_gap;
  81
  82 cover_registration_c_dy = -cover_strap_c_d_y - strap_w/2
  83   - side_wall_th - cover_registration_sz_y/2;
  84
  85 module BothSides(){
  86   for (m=[0,1]) {
  87     mirror([m,0,0]) {
  88       children();
  89     }
  90   }
  91 }
  92 module StrapCutouts(y_c, z_top){
  93   for (z = [ bottom_base_z, z_top ]) {
  94     BothSides(){
  95       translate([ -total_side_wall_x, y_c, z_top ]) {
  96         cube([ strap_cutout_x*2,
  97                strap_w,
  98                strap_cutout_z*2 ],
  99              center=true);
 100       }
 101     }
 102   }
 103 }
 104
 105 module CoverStrapCutouts(){
 106   StrapCutouts( -cover_strap_c_d_y, cover_top_z );
 107 }
 108
 109 module FrontWallsPlan(slop) {
 110   BothSides(){
 111     rectfromto([ -board_w/2 - side_wall_th,    0             ],
 112                [ -usb_w/2 - slop,              front_wall_th ]);
 113   }
 114 }
 115 module TopSmallWallsPlan() {
 116   for (m=[0,1]) {
 117     mirror([m,0]) {
 118       rectfromto([ -usb_w/2,              -0.01        ],
 119                  [ -usb_w/2 + usb_wall_w, usb_tongue_d ]);
 120     }
 121   }
 122   FrontWallsPlan(0);
 123   for (w=small_walls) {
 124     rectfromto(w[0], w[1]);
 125   }
 126 }
 127 module TopCeilPlan() {
 128   difference(){
 129     BothSides(){
 130       rectfromto([ -usb_w/2,              -0.01        ],
 131                  [ 0.1,                   usb_tongue_d ]);
 132       rectfromto([ -board_w/2 - side_wall_th, 0            ],
 133                  [ 0.1,                       ceil_y_min   ]);
 134     }
 135     rectfromto(chip_cutout[0], chip_cutout[1]);
 136   }
 137 }
 138 module TopMainWallsPlan() {
 139   BothSides(){
 140     rectfromto([ -board_w/2 - side_wall_th, 0          ],
 141                [ -board_w/2,                wall_y_min ]);
 142   }
 143   FrontWallsPlan(usb_tongue_w_slop);
 144   rectfromto([ -board_w/2 - side_wall_th + 0, -      board_l   ],
 145              [ +board_w/2 + side_wall_th,            total_y_min ]);
 146 }
 147
 148 module CoverRegistrations(){
 149   linextr_y_xz(cover_registration_c_dy - strap_w/2,
 150                cover_registration_c_dy + strap_w/2) {
 151     difference(){
 152       rectfromto([ -total_side_wall_x,
 153                           cover_wall_bot_z - cover_registration_sz_z  ],
 154                  [ +total_side_wall_x, cover_top_z ]);
 155       hull(){
 156         TopElevationForCutout();
 157         translate([0, -20]) TopElevationForCutout();
 158       }
 159     }
 160   }
 161 }
 162
 163 module Top(){ ////toplevel
 164   difference(){
 165     union(){
 166       linextr(0, usb_wall_h)
 167         TopSmallWallsPlan();
 168       linextr(usb_wall_h - usb_ceil_th, usb_wall_h)
 169         TopCeilPlan();
 170       linextr(-board_th, usb_wall_h)
 171         TopMainWallsPlan();
 172       BothSides()
 173         linextr(cover_wall_bot_z, top_top_z)
 174         rectfromto([ -(board_w/2 + 0.1),  total_y_min             ],
 175                    [ -total_side_wall_x,  main_y_min - fit_gap_y  ]);
 176     }
 177
 178     for (y_c = [strain_0_y_c, strain_1_y_c]) {
 179       for (x_c = [-1,+1] * strain_pitch_across/2) {
 180         translate([x_c, y_c, 0])
 181           linextr(-20, 20)
 182           square([ strain_t, strain_w ], center=true);
 183       }
 184     }
 185     linextr_y_xz(total_y_min-1, main_y_min)
 186       translate([0, top_base_z])
 187       scale([1, strain_groove_d/strain_groove_w])
 188       circle(strain_groove_w/2, $fn = 8);
 189   }
 190 }
 191
 192 module TopElevationForCutout(){
 193     rectfromto([ -(top_side_wall_x + side_x_gap), top_base_z ],
 194                [ +(top_side_wall_x + side_x_gap), top_top_z  ]);
 195 }
 196 module BottomMainElevation(){
 197   difference(){
 198     rectfromto([ -total_side_wall_x, bottom_base_z        ],
 199                [ +total_side_wall_x, bottom_wall_top_z    ]);
 200
 201     TopElevationForCutout();
 202   }
 203 }
 204 module Bottom(){ ////toplevel
 205   difference(){
 206     union(){
 207       linextr_y_xz(total_y_min, front_y_max)
 208         BottomMainElevation();
 209     }
 210
 211     linextr_y_xz(total_y_min + side_wall_th,
 212                  front_y_max - side_wall_th)
 213       rectfromto([ -board_w/2, bottom_base_z + bottom_floor_th ],
 214                  [ +board_w/2, 20         ]);
 215
 216     linextr_y_xz(total_y_min - 1,
 217                  total_y_min + side_wall_th + 1){
 218       translate([ 0, top_base_z ]){
 219         hull(){
 220           translate([ 0, -cable_dia/2 ])
 221             circle(r = cable_dia/2, $fa = 10, $fs = 1);
 222           square([ cable_dia, 0.1 ], center=true);
 223         }
 224       }
 225     }
 226     minkowski(){
 227       CoverRegistrations();
 228       cube([ 1, fit_gap_y*2, fit_gap_z*2 ], center=true);
 229     }
 230   }
 231 }
 232
 233 module CoverMainElevation(){
 234   difference(){
 235     rectfromto([ -total_side_wall_x, cover_wall_bot_z        ],
 236                [ +total_side_wall_x, cover_top_z    ]);
 237
 238     TopElevationForCutout();
 239   }
 240 }
 241 module Cover(){ ////toplevel
 242   difference(){
 243     union(){
 244       linextr_y_xz(main_y_min, front_y_max)
 245         CoverMainElevation();
 246       CoverRegistrations();
 247     }
 248     CoverStrapCutouts();
 249   }
 250 }
 251
 252 module BottomDemo(){ ////toplevel
 253   translate([0, 0, -0.25]) Bottom();
 254   %Top();
 255   translate([0, 0, +0.25]) Cover();
 256 }