| 1 | /* |
| 2 | Copyright (C) 2015 Daniel Watson |
| 3 | See the end of the file for license conditions. |
| 4 | */ |
| 5 | // challenge-bot |
| 6 | // GNU AGPLv3 (or later at your option) |
| 7 | // project available here: |
| 8 | // https://challenge-bot.com/ |
| 9 | |
| 10 | /* |
| 11 | this holds an hc-sr04 sonar sensor to a 3/16 inch deck. |
| 12 | http://fritzing.org/projects/hc-sr04-project |
| 13 | it can hold the sonar sensor either facing down, or forwards. |
| 14 | when facing down, it can detect if it passes over the edge of a table. |
| 15 | when facing forwards, it can detect and follow something in front of it. |
| 16 | */ |
| 17 | |
| 18 | $fn = 60; |
| 19 | |
| 20 | // 3/16 inch in mm deck_depth = 4.7625; |
| 21 | // 1/4 inch in mm = 6.35 |
| 22 | // subtract a little to be a squeeze fit |
| 23 | deck_depth = 4.7625 - 0.4; |
| 24 | // sonar sensor measurements taken with calipers: |
| 25 | // 10.82 in between, 42.33 outside, 15.82 diameter |
| 26 | // measured diameter of 15.82 with calipers, |
| 27 | // but when printed ends up being too small, so add some |
| 28 | sonar_diameter = 15.82 + 0.5; |
| 29 | sonar_radius = sonar_diameter / 2; |
| 30 | sonar_height = 13.8; |
| 31 | between_sonar_centers = sonar_diameter + 10.82; |
| 32 | // the sonar cylinders are placed on the pcb at slightly different positions |
| 33 | // from one sensor to the next, so this allows for that variance. |
| 34 | between_sonar_centers_variance = 2; |
| 35 | // keep at least this much plastic surrounding the sonar cylinder on all sides |
| 36 | buffer = 3; |
| 37 | sonar_holder_length = buffer + between_sonar_centers + sonar_diameter + buffer; |
| 38 | sonar_holder_width = buffer + sonar_diameter + buffer; |
| 39 | // sonar_holder_depth is deck_depth minus a little bit to make arm fit |
| 40 | // into deck holder |
| 41 | sonar_holder_depth = deck_depth - 0.7875; |
| 42 | |
| 43 | deck_holder_length = sonar_holder_depth * 2 + deck_depth + 15; |
| 44 | module sonar_holder_2d() { |
| 45 | difference() { |
| 46 | square([sonar_holder_length, sonar_holder_width]); } } |
| 47 | |
| 48 | module sonars() { |
| 49 | translate([between_sonar_centers / 2, 0, 0]) { |
| 50 | hull() { |
| 51 | cylinder(r = sonar_radius, h = sonar_height); |
| 52 | // for the variance with which the physical sonar cylinders are placed |
| 53 | translate([ -between_sonar_centers_variance, 0, 0]) { |
| 54 | cylinder(r = sonar_radius, h = sonar_height); } } } |
| 55 | translate([-between_sonar_centers / 2, 0, 0]) { |
| 56 | cylinder(r = sonar_radius, h = sonar_height); } } |
| 57 | |
| 58 | module sonar_holder() { |
| 59 | elbow_length = deck_depth - 0.2; |
| 60 | rounded_corner_radius = buffer; |
| 61 | difference() { |
| 62 | cube([sonar_holder_length, sonar_holder_width, sonar_holder_depth]); |
| 63 | translate([sonar_holder_length / 2, sonar_holder_width / 2, -0.05]) { |
| 64 | sonars(); } |
| 65 | translate([sonar_holder_length, |
| 66 | sonar_holder_width, |
| 67 | 0]) { |
| 68 | corner_rounder(rounded_corner_radius, |
| 69 | sonar_holder_depth, |
| 70 | "bottom-right"); } } |
| 71 | translate([sonar_holder_length, 0, 0]) { |
| 72 | cube([elbow_length, deck_depth, sonar_holder_depth]); |
| 73 | translate([elbow_length, 0, 0]) { |
| 74 | linear_extrude(height = sonar_holder_depth) { |
| 75 | polygon([[ 0, 0], |
| 76 | [sonar_holder_depth, 0], |
| 77 | [sonar_holder_depth, sonar_holder_width / 2], |
| 78 | [ 0, sonar_holder_width / 2 |
| 79 | + sonar_holder_depth]]); } |
| 80 | translate([0, (sonar_holder_width + sonar_holder_depth) / 2, 0]) { |
| 81 | cube([sonar_holder_depth / 2, |
| 82 | (sonar_holder_width - sonar_holder_depth) / 2 + 0.8, |
| 83 | sonar_holder_depth]); } |
| 84 | translate([-1.7, sonar_holder_width + 0.8, 0]) { |
| 85 | linear_extrude(height = sonar_holder_depth) { |
| 86 | polygon([[ 0, 0], |
| 87 | [sonar_holder_depth / 2 + 1.7, 4], |
| 88 | [sonar_holder_depth / 2 + 1.7, 0]]); } } } } } |
| 89 | |
| 90 | module corner_rounder_2d(radius, corner_name = "top-left") { |
| 91 | rotate_for_corner = (corner_name == "top-left") ? 0 : |
| 92 | ((corner_name == "top-right") ? -90 : |
| 93 | ((corner_name == "bottom-left") ? 90 : |
| 94 | ((corner_name == "bottom-right") ? 180 : |
| 95 | 1 / 0))); |
| 96 | rotate(rotate_for_corner) { |
| 97 | difference() { |
| 98 | square(radius); |
| 99 | translate([radius, radius]) { |
| 100 | circle(radius); } } } } |
| 101 | |
| 102 | module corner_rounder(radius, height, corner_name = "top-left") { |
| 103 | linear_extrude(height = height) { |
| 104 | corner_rounder_2d(radius, corner_name); } } |
| 105 | |
| 106 | /* |
| 107 | This file is part of challenge-bot. |
| 108 | |
| 109 | Challenge-bot is free software: you can redistribute it and/or modify |
| 110 | it under the terms of the GNU Affero General Public License as published by |
| 111 | the Free Software Foundation, either version 3 of the License, or |
| 112 | (at your option) any later version. |
| 113 | |
| 114 | GNU Affero Emacs is distributed in the hope that it will be useful, |
| 115 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 116 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 117 | GNU Affero General Public License for more details. |
| 118 | |
| 119 | You should have received a copy of the GNU Affero General Public License |
| 120 | along with challenge-bot. If not, see <http://www.gnu.org/licenses/>. |
| 121 | */ |