// ============================================================ // RPLIDAR A1 Mount Bracket — Issue #596 // Agent : sl-mechanical // Date : 2026-03-14 // Part catalogue: // 1. tnut_base — 2020 T-slot rail interface plate with M5 T-nut captive pockets // 2. column — hollow elevation column, 120 mm tall, 3 stiffening ribs, cable bore // 3. scan_platform — top plate with Ø40 mm BC M3 mounting pattern, vibration seats // 4. vibe_ring — silicone FC-grommet isolation ring for scan_platform bolts // 5. cable_guide — snap-on cable management clip for column body // // BOM: // 2 × M5×10 BHCS + M5 T-nuts (tnut_base to rail) // 4 × M3×8 SHCS (scan_platform to RPLIDAR A1) // 4 × M3 silicone FC grommets Ø8.5 OD / Ø3.2 bore (anti-vibe) // 4 × M3 hex nuts (captured in scan_platform) // // Print settings (PETG): // tnut_base / column / scan_platform : 5 perimeters, 40 % gyroid, no supports // vibe_ring : 3 perimeters, 20 % gyroid, no supports // cable_guide : 3 perimeters, 30 % gyroid, no supports // // Export commands: // openscad -D 'RENDER="tnut_base"' -o tnut_base.stl rplidar_mount.scad // openscad -D 'RENDER="column"' -o column.stl rplidar_mount.scad // openscad -D 'RENDER="scan_platform"' -o scan_platform.stl rplidar_mount.scad // openscad -D 'RENDER="vibe_ring"' -o vibe_ring.stl rplidar_mount.scad // openscad -D 'RENDER="cable_guide"' -o cable_guide.stl rplidar_mount.scad // openscad -D 'RENDER="assembly"' -o assembly.png rplidar_mount.scad // ============================================================ // ── Render selector ───────────────────────────────────────── RENDER = "assembly"; // tnut_base | column | scan_platform | vibe_ring | cable_guide | assembly // ── Global constants ──────────────────────────────────────── $fn = 64; EPS = 0.01; // 2020 rail RAIL_W = 20.0; // extrusion cross-section RAIL_H = 20.0; SLOT_NECK_H = 3.2; // T-slot opening width TNUT_W = 9.8; // M5 T-nut width TNUT_H = 5.5; // T-nut height (depth into slot) TNUT_L = 12.0; // T-nut body length M5_D = 5.2; // M5 clearance bore M5_HEAD_D = 9.5; // M5 BHCS head diameter M5_HEAD_H = 4.0; // M5 BHCS head height // Base plate BASE_L = 60.0; // length along rail axis BASE_W = 30.0; // width across rail BASE_T = 8.0; // plate thickness BOLT_PITCH = 40.0; // M5 bolt pitch along rail (centre-to-centre) // Elevation column COL_OD = 25.0; // column outer diameter COL_ID = 17.0; // inner bore (cable routing) ELEV_H = 120.0; // scan plane above rail top face COL_WALL = (COL_OD - COL_ID) / 2; RIB_W = 3.0; // stiffening rib width RIB_H = 3.5; // rib radial height CABLE_SLOT_W = 8.0; // cable entry slot width CABLE_SLOT_H = 5.0; // cable entry slot height // Scan platform PLAT_D = 60.0; // platform disc diameter (clears RPLIDAR body Ø100 mm well) PLAT_T = 6.0; // platform thickness RPL_BC_D = 40.0; // RPLIDAR M3 bolt circle diameter (4 bolts at 45 °) RPL_BORE_D = 36.0; // central pass-through for scan motor cable M3_D = 3.2; // M3 clearance bore M3_NUT_W = 5.5; // M3 hex nut across-flats M3_NUT_H = 2.4; // M3 hex nut height GROM_OD = 8.5; // FC silicone grommet OD GROM_ID = 3.2; // grommet bore GROM_H = 3.0; // grommet seat depth CONN_SLOT_W = 12.0; // connector side-exit slot width CONN_SLOT_H = 5.0; // connector slot height // Vibe ring VRING_OD = GROM_OD + 1.6; // printed retainer OD VRING_ID = GROM_ID + 0.3; // pass-through with grommet seated VRING_T = 2.0; // ring flange thickness // Cable guide clip CLIP_W = 14.0; CLIP_T = 3.5; CLIP_GAP = COL_OD + 0.4; // snap-fit gap (slight interference) SNAP_T = 1.8; CABLE_CH_W = 8.0; CABLE_CH_H = 5.0; // ── Utility modules ───────────────────────────────────────── module chamfer_cube(size, ch=1.0) { // simple chamfered box (bottom edge only for printability) hull() { translate([ch, ch, 0]) cube([size[0]-2*ch, size[1]-2*ch, EPS]); translate([0, 0, ch]) cube(size - [0, 0, ch]); } } module hex_pocket(af, depth) { // hex nut pocket (flat-to-flat af) cylinder(d = af / cos(30), h = depth, $fn = 6); } // ── Part 1: tnut_base ─────────────────────────────────────── module tnut_base() { difference() { // Body union() { chamfer_cube([BASE_L, BASE_W, BASE_T], ch=1.5); // Column socket boss centred on plate top face translate([BASE_L/2, BASE_W/2, BASE_T]) cylinder(d=COL_OD + 4.0, h=8.0); } // M5 bolt holes (counterbored for BHCS heads from underneath) for (x = [BASE_L/2 - BOLT_PITCH/2, BASE_L/2 + BOLT_PITCH/2]) translate([x, BASE_W/2, -EPS]) { cylinder(d=M5_D, h=BASE_T + 8.0 + 2*EPS); // counterbore from bottom cylinder(d=M5_HEAD_D, h=M5_HEAD_H + EPS); } // T-nut captive pockets (accessible from bottom) for (x = [BASE_L/2 - BOLT_PITCH/2, BASE_L/2 + BOLT_PITCH/2]) translate([x - TNUT_L/2, BASE_W/2 - TNUT_W/2, BASE_T - TNUT_H]) cube([TNUT_L, TNUT_W, TNUT_H + EPS]); // Column bore into boss translate([BASE_L/2, BASE_W/2, BASE_T - EPS]) cylinder(d=COL_OD + 0.3, h=8.0 + 2*EPS); // Cable exit slot through base (offset 5 mm from column centre) translate([BASE_L/2 - CABLE_SLOT_W/2, BASE_W/2 + COL_OD/4, -EPS]) cube([CABLE_SLOT_W, CABLE_SLOT_H, BASE_T + 8.0 + 2*EPS]); // Weight relief pockets on underside for (x = [BASE_L/2 - BOLT_PITCH/2 + 10, BASE_L/2 + BOLT_PITCH/2 - 10]) for (y = [7, BASE_W - 7]) translate([x - 5, y - 5, -EPS]) cube([10, 10, BASE_T/2]); } } // ── Part 2: column ────────────────────────────────────────── module column() { // Actual column height: ELEV_H minus base boss engagement (8 mm) and platform seating (6 mm) col_h = ELEV_H - 8.0 - PLAT_T; difference() { union() { // Hollow tube cylinder(d=COL_OD, h=col_h); // Three 120°-spaced stiffening ribs along full height for (a = [0, 120, 240]) rotate([0, 0, a]) translate([COL_OD/2 - EPS, -RIB_W/2, 0]) cube([RIB_H, RIB_W, col_h]); // Bottom spigot (fits into base boss bore) translate([0, 0, -6.0]) cylinder(d=COL_OD - 0.4, h=6.0 + EPS); // Top spigot (seats into scan_platform recess) translate([0, 0, col_h - EPS]) cylinder(d=COL_OD - 0.4, h=6.0); } // Inner cable bore translate([0, 0, -6.0 - EPS]) cylinder(d=COL_ID, h=col_h + 12.0 + 2*EPS); // Cable entry slot at bottom (aligns with base slot) translate([-CABLE_SLOT_W/2, -COL_OD/2 - EPS, 2.0]) cube([CABLE_SLOT_W, CABLE_SLOT_H + EPS, CABLE_SLOT_H]); // Cable exit slot at top (90° rotated for tidy routing) rotate([0, 0, 90]) translate([-CABLE_SLOT_W/2, -COL_OD/2 - EPS, col_h - CABLE_SLOT_H - 4.0]) cube([CABLE_SLOT_W, CABLE_SLOT_H + EPS, CABLE_SLOT_H]); // Cable clip snap groove (at mid-height) translate([0, 0, col_h / 2]) difference() { cylinder(d=COL_OD + 2*RIB_H + 0.8, h=4.0, center=true); cylinder(d=COL_OD - 0.2, h=4.0 + 2*EPS, center=true); } } } // ── Part 3: scan_platform ─────────────────────────────────── module scan_platform() { difference() { union() { // Main disc cylinder(d=PLAT_D, h=PLAT_T); // Rim lip for stiffness translate([0, 0, PLAT_T]) difference() { cylinder(d=PLAT_D, h=2.0); cylinder(d=PLAT_D - 4.0, h=2.0 + EPS); } } // Central cable pass-through translate([0, 0, -EPS]) cylinder(d=RPL_BORE_D, h=PLAT_T + 4.0); // Column spigot socket (bottom recess) translate([0, 0, -EPS]) cylinder(d=COL_OD - 0.4 + 0.4, h=6.0); // RPLIDAR M3 mounting holes — 4× on Ø40 BC at 45°/135°/225°/315° for (a = [45, 135, 225, 315]) rotate([0, 0, a]) translate([RPL_BC_D/2, 0, -EPS]) { // Through bore cylinder(d=M3_D, h=PLAT_T + 2*EPS); // Grommet seat (countersunk from top) translate([0, 0, PLAT_T - GROM_H]) cylinder(d=GROM_OD + 0.3, h=GROM_H + EPS); // Captured M3 hex nut pocket (from bottom) translate([0, 0, 1.5]) hex_pocket(M3_NUT_W + 0.3, M3_NUT_H + 0.2); } // Connector side-exit slots (2× opposing, at 0° and 180°) for (a = [0, 180]) rotate([0, 0, a]) translate([-CONN_SLOT_W/2, PLAT_D/2 - CONN_SLOT_H, -EPS]) cube([CONN_SLOT_W, CONN_SLOT_H + EPS, PLAT_T + 2*EPS]); // Weight relief pockets (2× lateral) for (a = [90, 270]) rotate([0, 0, a]) translate([-10, 15, 1.5]) cube([20, 8, PLAT_T - 3.0]); } } // ── Part 4: vibe_ring ─────────────────────────────────────── // Printed silicone-grommet retainer ring — press-fits over M3 bolt with grommet seated module vibe_ring() { difference() { union() { cylinder(d=VRING_OD, h=VRING_T + GROM_H); // Flange cylinder(d=VRING_OD + 2.0, h=VRING_T); } // Bore translate([0, 0, -EPS]) cylinder(d=VRING_ID, h=VRING_T + GROM_H + 2*EPS); } } // ── Part 5: cable_guide ───────────────────────────────────── // Snap-on cable clip for column mid-section module cable_guide() { arm_t = SNAP_T; gap = CLIP_GAP; difference() { union() { // Saddle body (U-shape wrapping column) difference() { cylinder(d=gap + 2*CLIP_T, h=CLIP_W); translate([0, 0, -EPS]) cylinder(d=gap, h=CLIP_W + 2*EPS); // Open front slot for snap insertion translate([-gap/2, 0, -EPS]) cube([gap, gap/2 + CLIP_T + EPS, CLIP_W + 2*EPS]); } // Snap arms for (s = [-1, 1]) translate([s*(gap/2 - arm_t), 0, 0]) mirror([s < 0 ? 1 : 0, 0, 0]) translate([0, -arm_t/2, 0]) cube([arm_t + 1.5, arm_t, CLIP_W]); // Cable channel bracket (side-mounted) translate([gap/2 + CLIP_T, -(CABLE_CH_W/2 + CLIP_T), 0]) cube([CLIP_T + CABLE_CH_H, CABLE_CH_W + 2*CLIP_T, CLIP_W]); } // Cable channel cutout translate([gap/2 + CLIP_T + CLIP_T - EPS, -CABLE_CH_W/2, -EPS]) cube([CABLE_CH_H + EPS, CABLE_CH_W, CLIP_W + 2*EPS]); // Snap tip undercut (both arms) for (s = [-1, 1]) translate([s*(gap/2 + CLIP_T + 1.0), -arm_t, -EPS]) rotate([0, 0, s*30]) cube([2, arm_t*2, CLIP_W + 2*EPS]); } } // ── Assembly / render dispatch ─────────────────────────────── module assembly() { // tnut_base at origin color("SteelBlue") tnut_base(); // column rising from base boss color("DodgerBlue") translate([BASE_L/2, BASE_W/2, BASE_T + 8.0 - 6.0]) column(); // scan_platform at top of column col_h_actual = ELEV_H - 8.0 - PLAT_T; color("CornflowerBlue") translate([BASE_L/2, BASE_W/2, BASE_T + 8.0 - 6.0 + col_h_actual + 6.0 - EPS]) scan_platform(); // vibe rings (4×) seated in platform holes for (a = [45, 135, 225, 315]) color("Gray", 0.7) translate([BASE_L/2, BASE_W/2, BASE_T + 8.0 - 6.0 + col_h_actual + 6.0 + PLAT_T - GROM_H]) rotate([0, 0, a]) translate([RPL_BC_D/2, 0, 0]) vibe_ring(); // cable_guide clipped at column mid-height color("LightSteelBlue") translate([BASE_L/2, BASE_W/2, BASE_T + 8.0 - 6.0 + (ELEV_H - 8.0 - PLAT_T)/2 - CLIP_W/2]) cable_guide(); } // ── Dispatch ──────────────────────────────────────────────── if (RENDER == "tnut_base") tnut_base(); else if (RENDER == "column") column(); else if (RENDER == "scan_platform") scan_platform(); else if (RENDER == "vibe_ring") vibe_ring(); else if (RENDER == "cable_guide") cable_guide(); else assembly();