| 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 + 0.4; |
| 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 | binder_clip_attacher_length = 30; // not measured; just a rough estimate |
| 38 | screw_hole = 2.2; |
| 39 | sonar_holder_length = buffer + between_sonar_centers + sonar_diameter + buffer + binder_clip_attacher_length; |
| 40 | sonar_holder_width = buffer + sonar_diameter + buffer; |
| 41 | // sonar_holder_depth is deck_depth minus a little bit to make arm fit |
| 42 | // into deck holder |
| 43 | sonar_holder_depth = deck_depth - 0.7875; |
| 44 | |
| 45 | deck_holder_length = sonar_holder_depth * 2 + deck_depth + 15; |
| 46 | module sonar_holder_2d() { |
| 47 | difference() { |
| 48 | square([sonar_holder_length, sonar_holder_width]); } } |
| 49 | |
| 50 | module sonars() { |
| 51 | translate([between_sonar_centers / 2, 0, 0]) { |
| 52 | cylinder(r = sonar_radius, h = sonar_height); } |
| 53 | // for the variance with which the physical sonar cylinders are placed |
| 54 | translate([between_sonar_centers / 2 - between_sonar_centers_variance, 0, 0]) { |
| 55 | cylinder(r = sonar_radius, h = sonar_height); |
| 56 | translate([0, -sonar_radius, 0]) { |
| 57 | cube([between_sonar_centers_variance, sonar_diameter, sonar_height]); } } |
| 58 | translate([-between_sonar_centers / 2, 0, 0]) { |
| 59 | cylinder(r = sonar_radius, h = sonar_height); } } |
| 60 | |
| 61 | module sonar_holder() { |
| 62 | difference() { |
| 63 | difference() { |
| 64 | cube([sonar_holder_length, sonar_holder_width, sonar_holder_depth]); |
| 65 | translate([sonar_holder_length - between_sonar_centers, sonar_holder_width / 2, -0.05]) { |
| 66 | sonars(); } } |
| 67 | translate([binder_clip_attacher_length / 2, sonar_holder_width / 2], 0) { |
| 68 | cylinder(r = screw_hole, h = sonar_holder_depth); } } } |
| 69 | |
| 70 | module attaching_piece() { |
| 71 | linear_extrude(height = sonar_holder_depth) { |
| 72 | difference() { |
| 73 | square(sonar_holder_width, center = true); |
| 74 | circle(screw_hole); } } } |
| 75 | |
| 76 | /* |
| 77 | This file is part of challenge-bot. |
| 78 | |
| 79 | Challenge-bot is free software: you can redistribute it and/or modify |
| 80 | it under the terms of the GNU Affero General Public License as published by |
| 81 | the Free Software Foundation, either version 3 of the License, or |
| 82 | (at your option) any later version. |
| 83 | |
| 84 | GNU Affero Emacs is distributed in the hope that it will be useful, |
| 85 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 86 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 87 | GNU Affero General Public License for more details. |
| 88 | |
| 89 | You should have received a copy of the GNU Affero General Public License |
| 90 | along with challenge-bot. If not, see <http://www.gnu.org/licenses/>. |
| 91 | */ |