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 = sqrt(2 * pow(wheel_square_spoke_size / 2, 2)) + wall_width / 2;
  19
  20 motor_shaft_radius = 3.7;
  21 motor_shaft_flat_width = 4.8;
  22
  23 tread_radius = 4 / 2;
  24
  25 module mounting_screw_flat() {
  26   circle(0.9); }
  27
  28 module motor_shaft_flat(radius, flat_width) {
  29   intersection() {
  30     circle(radius);
  31     square([flat_width, radius * 2], center = true); } }
  32
  33 module motor_shaft(radius,
  34                    flat_width,
  35                    shaft_length) {
  36   linear_extrude(height = shaft_length) {
  37     motor_shaft_flat(radius, flat_width); } }
  38
  39 module rim(radius, wall_width, wheel_width) {
  40   linear_extrude(height = wheel_width) {
  41     difference() {
  42       circle(radius);
  43       circle(radius - wall_width); } } }
  44
  45 module motor_shaft_holder_flat(radius, flat_width, wall_width) {
  46   difference() {
  47     motor_shaft_flat(radius + wall_width,
  48                      flat_width + wall_width);
  49     motor_shaft_flat(radius, flat_width); } }
  50
  51 module motor_shaft_holder(radius, flat_width, wall_width, height) {
  52   linear_extrude(height = height) {
  53     motor_shaft_holder_flat(radius, flat_width, wall_width); } }
  54
  55 module tread(wheel_radius, tread_radius) {
  56   rotate_extrude(convexity = 10) {
  57     translate([wheel_radius, 0]) {
  58       circle(tread_radius); } } }
  59
  60 module wheel(radius,
  61              width,
  62              shaft_radius,
  63              shaft_flat_width,
  64              wall_width,
  65              tread_radius) {
  66   difference() {
  67     rim(radius, wall_width * 2, width);
  68     translate([0, 0, width / 2]) {
  69       tread(radius, tread_radius); } }
  70   linear_extrude(height = wheel_square_spoke_thickness) {
  71     difference() {
  72       square(wheel_square_spoke_size, center = true);
  73       mounting_screw_flat(); } }
  74   translate([0, 0, wheel_square_spoke_thickness]) {
  75     motor_shaft_holder(shaft_radius,
  76                        shaft_flat_width,
  77                        wall_width,
  78                        width - wheel_square_spoke_thickness); } }