challenge-bot.com Git - challenge-bot/blob - 3d-printables/wheel-data.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 // use $fn = 20 while developing, 100 when about to print
   8 //  20 will make previews fast
   9 //  100 will make printing smooth
  10 $fn = 100;
  11
  12 wheel_square_spoke_size = 45;
  13 wheel_square_spoke_thickness = 2;
  14
  15 wall_width = 3;
  16
  17 wheel_width = 9;
  18 wheel_radius =
  19   sqrt(2 * pow(wheel_square_spoke_size / 2, 2)) + wall_width / 2 + 1;
  20
  21 motor_shaft_radius = 3.7;
  22 motor_shaft_flat_width = 4.8;
  23
  24 tread_radius = 4 / 2;
  25
  26 module mounting_screw_flat() {
  27   circle(1.1); }
  28
  29 module motor_shaft_flat(radius, flat_width) {
  30   intersection() {
  31     circle(radius);
  32     square([flat_width, radius * 2], center = true); } }
  33
  34 module motor_shaft(radius,
  35                    flat_width,
  36                    shaft_length) {
  37   linear_extrude(height = shaft_length) {
  38     motor_shaft_flat(radius, flat_width); } }
  39
  40 module rim(radius, wall_width, wheel_width) {
  41   linear_extrude(height = wheel_width) {
  42     difference() {
  43       circle(radius);
  44       circle(radius - wall_width); } } }
  45
  46 module motor_shaft_holder_flat(radius, flat_width, wall_width) {
  47   difference() {
  48     motor_shaft_flat(radius + wall_width,
  49                      flat_width + wall_width);
  50     motor_shaft_flat(radius, flat_width); } }
  51
  52 module motor_shaft_holder(radius, flat_width, wall_width, height) {
  53   linear_extrude(height = height) {
  54     motor_shaft_holder_flat(radius, flat_width, wall_width); } }
  55
  56 module tread(wheel_radius, tread_radius) {
  57   rotate_extrude(convexity = 10) {
  58     translate([wheel_radius, 0]) {
  59       circle(tread_radius); } } }
  60
  61 module wheel(radius,
  62              width,
  63              shaft_radius,
  64              shaft_flat_width,
  65              wall_width,
  66              tread_radius) {
  67   difference() {
  68     rim(radius, wall_width * 2, width);
  69     translate([0, 0, width / 2]) {
  70       tread(radius, tread_radius); } }
  71   linear_extrude(height = wheel_square_spoke_thickness) {
  72     difference() {
  73       square(wheel_square_spoke_size, center = true);
  74       mounting_screw_flat(); } }
  75   translate([0, 0, wheel_square_spoke_thickness]) {
  76     motor_shaft_holder(shaft_radius,
  77                        shaft_flat_width,
  78                        wall_width,
  79                        width - wheel_square_spoke_thickness); } }