challenge-bot.com Git - challenge-bot/blob - 3d-printables/sonar-table-top-holder.scad

   1 // challenge-bot
   2 // GNU AGPLv3 (or later at your option)
   3 // project available at these locations:
   4 // https://gitorious.org/ozzloy/challenge-bot
   5 // https://github.com/waynegramlich/challenge-bot
   6
   7 /*
   8   this holds an hc-sr04 sonar sensor to a 3/16 inch deck.
   9   http://fritzing.org/projects/hc-sr04-project
  10   it can hold the sonar sensor either facing down, or forwards.
  11   when facing down, it can detect if it passes over the edge of a table.
  12   when facing forwards, it can detect and follow something in front of it.
  13  */
  14
  15 $fn = 60;
  16
  17 use <oshw.scad>
  18 oshw_dy = 120.366;
  19 oshw_dx = 133.888;
  20
  21 // 3/16 inch in mm deck_depth = 4.7625;
  22 // 1/4 inch in mm = 6.35
  23 // subtract a little to be a squeeze fit
  24 deck_depth = 4.7625 - 0.4;
  25 // sonar sensor measurements taken with calipers:
  26 //  10.82 in between, 42.33 outside, 15.82 diameter
  27 // measured diameter of 15.82 with calipers,
  28 //  but when printed ends up being too small, so add some
  29 sonar_diameter = 15.82 + 0.4;
  30 sonar_radius = sonar_diameter / 2;
  31 sonar_height = 13.8;
  32 between_sonar_centers = sonar_diameter + 10.82;
  33 // the sonar cylinders are placed on the pcb at slightly different positions
  34 //  from one sensor to the next, so this allows for that variance.
  35 between_sonar_centers_variance = 2;
  36 // keep at least this much plastic surrounding the sonar cylinder on all sides
  37 buffer = 3;
  38 sonar_holder_length = buffer + between_sonar_centers + sonar_diameter + buffer;
  39 sonar_holder_width = buffer + sonar_diameter + buffer;
  40 // sonar_holder_depth is deck_depth minus a little bit to make arm fit
  41 //  into deck holder
  42 sonar_holder_depth = deck_depth - 0.7875;
  43
  44 deck_holder_length = sonar_holder_depth * 2 + deck_depth + 15;
  45
  46 module sonars(){
  47   translate([between_sonar_centers / 2, 0, 0]){
  48     cylinder(r = sonar_radius, h = sonar_height);}
  49   // for the variance with which the physical sonar cylinders are placed
  50   translate([between_sonar_centers / 2 - between_sonar_centers_variance, 0, 0]){
  51     cylinder(r = sonar_radius, h = sonar_height);
  52     translate([0, -sonar_radius, 0]){
  53       cube([between_sonar_centers_variance, sonar_diameter, sonar_height]);}}
  54   translate([-between_sonar_centers / 2, 0, 0]){
  55     cylinder(r = sonar_radius, h = sonar_height);}}
  56
  57 module sonar_holder(){
  58   elbow_length = deck_depth - 0.5;
  59   rounded_corner_radius = buffer;
  60   difference(){
  61     cube([sonar_holder_length, sonar_holder_width, sonar_holder_depth]);
  62     translate([sonar_holder_length / 2, sonar_holder_width / 2, -0.05]){
  63       sonars();}
  64     translate([sonar_holder_length - rounded_corner_radius,
  65                sonar_holder_width - rounded_corner_radius,
  66                0]){
  67       corner_rounder(rounded_corner_radius, sonar_holder_depth);}}
  68   translate([sonar_holder_length, 0, 0]){
  69     cube([elbow_length, deck_depth, sonar_holder_depth]);
  70     translate([elbow_length, 0, 0]){
  71       linear_extrude(height = sonar_holder_depth){
  72         polygon([[                 0, 0],
  73                  [sonar_holder_depth, 0],
  74                  [sonar_holder_depth, sonar_holder_width / 2],
  75                  [                 0,
  76                   sonar_holder_width / 2 + sonar_holder_depth]]);}
  77       translate([0, (sonar_holder_width + sonar_holder_depth) / 2, 0]){
  78         cube([sonar_holder_depth / 2,
  79               (sonar_holder_width - sonar_holder_depth) / 2 + 0.8,
  80               sonar_holder_depth]);}
  81       translate([-1.7, sonar_holder_width + 0.8, 0]){
  82         linear_extrude(height = sonar_holder_depth){
  83           polygon([[                           0, 0],
  84                    [sonar_holder_depth / 2 + 1.7, 4],
  85                    [sonar_holder_depth / 2 + 1.7, 0]]);}}}}}
  86
  87 module deck_holder(){
  88   deck_holder_width = sonar_holder_width - deck_depth;
  89   deck_holder_height = sonar_holder_depth * 2 + deck_depth;
  90   linear_extrude(height = deck_holder_width){
  91     difference(){
  92       square([deck_holder_length, deck_holder_height]);
  93       translate([sonar_holder_depth, sonar_holder_depth]){
  94         square(deck_depth);}
  95       translate([deck_holder_height, sonar_holder_depth]){
  96         square([deck_holder_length - (deck_holder_height), deck_depth]);}}}
  97   translate([deck_holder_length - oshw_dy * 0.05, 0, deck_holder_width / 2])
  98     scale([0.1, 1, 0.1])
  99       rotate(v = [1, 0, 0], a = 90)
 100         rotate(90)
 101           linear_extrude(height = 0.5)
 102             oshw();
 103   translate([deck_holder_length - oshw_dy * 0.05,
 104              deck_holder_height + 0.5,
 105              deck_holder_width / 2])
 106     rotate(v = [1, 0, 0], a = 90)
 107       rotate(90)
 108         scale([0.1, 0.1, 1])
 109           linear_extrude(height = 0.5)
 110             oshw();}
 111
 112 module corner_rounder_2d(radius){
 113     difference (){
 114         square (radius);
 115         circle (radius);}}
 116
 117 module corner_rounder(radius, height){
 118     linear_extrude(height = height){
 119         corner_rounder_2d(radius);}}
 120
 121 deck_holder();
 122
 123 translate([0, sonar_holder_depth * 2 + deck_depth + 2, 0]){
 124   sonar_holder();}