chassis/imx219_mount.scad

@@ -0,0 +1,104 @@
+// ============================================================
+// imx219_mount.scad — IMX219 Camera Radial Arm  Rev A
+// Agent: sl-mechanical   2026-02-28
+// ============================================================
+// Radial arm bracket for 32×32 mm IMX219 camera PCB.
+// 4× arms at 0/90/180/270° around the sensor_head platform.
+// Camera face tilted 10° nose-down.  CSI ribbon slot along arm.
+//
+// Print: one arm at a time, flat-side-down — no supports.
+//
+// RENDER options:
+//   "arm"          single arm for slicing (default)
+//   "assembly"     all 4 arms positioned around origin
+// ============================================================
+
+RENDER = "arm";
+
+// ── Camera PCB (IMX219, 32×32 mm) ────────────────────────────
+PCB_SIZE    = 32.0;          // PCB square side
+// M2 hole pattern: 24×24 mm square (±12 mm from centre)
+M2_SPACING  = 24.0;
+M2_D        =  2.4;          // M2 clearance hole
+
+// ── Arm geometry ─────────────────────────────────────────────
+// Arm is centred on Y=0, extends in +X direction from origin.
+// Base attachment holes near X=0; camera face plate at X=REACH_LEN.
+
+ARM_W       = 26.0;          // arm width (Y direction, centred)
+ARM_H       =  5.0;          // arm thickness (Z direction)
+
+// Must match sensor_head.scad ARM_R and ARM_DY_CAM
+ARM_R       = 50.0;          // platform attachment radius (used in assembly view)
+ARM_DY      =  9.0;          // half-spacing of M4 base attachment holes (Y axis)
+ARM_BOLT_X  =  8.0;          // base bolt CL from arm base (X)
+
+REACH_LEN   = 52.0;          // arm extension (X)
+
+FACE_SZ     = PCB_SIZE + 6.0;  // camera face plate side (38 mm)
+FACE_THICK  =  4.0;            // face plate thickness (X)
+
+TILT        = 10.0;          // nose-down tilt angle (degrees)
+
+// CSI ribbon slot — runs along bottom face of arm
+CSI_W       = 16.0;          // ribbon clearance width
+CSI_H       =  2.0;          // slot depth
+
+// ── Fasteners ─────────────────────────────────────────────────
+M4_D        =  4.5;          // M4 clearance hole
+
+$fn = 64;
+e   = 0.01;
+
+// ─────────────────────────────────────────────────────────────
+// imx219_arm()
+//   Arm centred on Y=0.  Base at X=0, tip at X=REACH_LEN.
+// ─────────────────────────────────────────────────────────────
+module imx219_arm() {
+    difference() {
+        union() {
+            // Arm body — centred on Y axis
+            translate([0, -ARM_W/2, 0])
+                cube([REACH_LEN, ARM_W, ARM_H]);
+
+            // Camera face plate at tip, tilted TILT° nose-down
+            translate([REACH_LEN, 0, ARM_H/2])
+                rotate([0, TILT, 0])
+                    translate([0, -FACE_SZ/2, -FACE_SZ/2])
+                        cube([FACE_THICK, FACE_SZ, FACE_SZ]);
+        }
+
+        // ── 2× M4 base attachment holes ───────────────────────
+        for (s = [-1, 1])
+            translate([ARM_BOLT_X, s * ARM_DY, -e])
+                cylinder(d = M4_D, h = ARM_H + 2*e);
+
+        // ── CSI ribbon slot — bottom face of arm ──────────────
+        translate([REACH_LEN * 0.2, -CSI_W/2, -e])
+            cube([REACH_LEN * 0.6, CSI_W, CSI_H + e]);
+
+        // ── 4× M2 camera PCB holes on face plate ─────────────
+        translate([REACH_LEN, 0, ARM_H/2])
+            rotate([0, TILT, 0])
+                for (dy = [-M2_SPACING/2, M2_SPACING/2])
+                    for (dz = [-M2_SPACING/2, M2_SPACING/2])
+                        translate([-e, dy, dz])
+                            rotate([0, 90, 0])
+                                cylinder(d = M2_D, h = FACE_THICK + 2*e);
+    }
+}
+
+// ─────────────────────────────────────────────────────────────
+// Render selector
+// ─────────────────────────────────────────────────────────────
+if (RENDER == "arm") {
+    imx219_arm();
+
+} else if (RENDER == "assembly") {
+    // 4 arms at 90° intervals, base at ARM_R from stem CL
+    for (a = [0, 90, 180, 270])
+        rotate([0, 0, a])
+            translate([ARM_R, 0, 0])
+                color("SkyBlue", 0.9)
+                    imx219_arm();
+}

chassis/realsense_mount.scad

@@ -0,0 +1,114 @@
+// ============================================================
+// realsense_mount.scad — RealSense D435i Bracket  Rev A
+// Agent: sl-mechanical   2026-02-28
+// ============================================================
+// Single-piece bracket. Bolts to sensor_head platform front
+// face via 2× M4 bolts.  Holds D435i at 10° nose-down tilt.
+//
+// RealSense D435i specs used:
+//   Body: 90 × 25 × 25 mm (W × H × D)
+//   Mount: 1/4-20 UNC female (bottom centre)
+//
+// Print orientation: flat base face on build plate — no supports.
+//
+// RENDER options:
+//   "bracket"    print-ready single piece (default)
+//   "assembly"   bracket + camera outline
+// ============================================================
+
+RENDER = "bracket";
+
+// ── Camera body ──────────────────────────────────────────────
+CAM_W       = 90.0;          // camera width
+CAM_H       = 25.0;          // camera height
+CAM_D       = 25.0;          // camera depth
+
+// ── Bracket geometry ─────────────────────────────────────────
+BASE_W      = 40.0;          // base plate width (Y direction)
+BASE_D      = 20.0;          // base plate depth (X direction)
+BASE_H      =  8.0;          // base plate thickness (Z direction)
+
+ARM_W       = 24.0;          // arm width
+ARM_H       =  8.0;          // arm thickness
+ARM_LEN     = 75.0;          // arm length (X direction from base edge)
+
+FACE_W      = 30.0;          // camera face plate width
+FACE_D      =  8.0;          // face plate thickness (holds camera)
+TILT        = 10.0;          // nose-down tilt (degrees)
+
+// ── Fasteners ────────────────────────────────────────────────
+M4_D        =  4.5;          // M4 clearance hole
+M4_DY       = 18.0;          // half-spacing of base attachment holes
+                              // ← must match sensor_head ARM_DY_RS
+
+// 1/4-20 UNC: tap drill ≈ 5.5 mm.
+// We print a nut pocket for a 1/4-20 hex nut captured in the face.
+NUT1420_AF  = 11.1;          // 1/4-20 hex nut across-flats (7/16")
+NUT1420_H   =  5.6;          // 1/4-20 hex nut thickness (7/32")
+NUT1420_BORE=  6.5;          // 1/4-20 bolt clearance through face
+NUT_POCKET_EXTRA = 0.4;      // print clearance on nut pocket
+
+$fn = 64;
+e   = 0.01;
+
+// ─────────────────────────────────────────────────────────────
+module realsense_bracket() {
+    union() {
+        // ── Base plate (attaches to platform top) ────────────
+        difference() {
+            translate([-BASE_D, -BASE_W/2, 0])
+                cube([BASE_D, BASE_W, BASE_H]);
+
+            // 2× M4 holes through base, ±ARM_DY_RS
+            for (dy = [-M4_DY, M4_DY])
+                translate([-BASE_D/2, dy, -e])
+                    cylinder(d = M4_D, h = BASE_H + 2*e);
+        }
+
+        // ── Arm extending in +X direction ────────────────────
+        difference() {
+            hull() {
+                translate([0,     -ARM_W/2, 0]) cube([e,     ARM_W, ARM_H]);
+                translate([ARM_LEN,-ARM_W/2, 0]) cube([e,    ARM_W, ARM_H]);
+            }
+            // No internal cuts here — arm is solid for rigidity
+        }
+
+        // ── Camera face plate at arm tip, tilted TILT° down ──
+        translate([ARM_LEN, 0, ARM_H/2])
+            rotate([0, TILT, 0])
+                translate([0, 0, -ARM_H/2])
+                    difference() {
+                        translate([0, -FACE_W/2, 0])
+                            cube([FACE_D, FACE_W, CAM_H + 6]);
+
+                        // 1/4-20 hex nut pocket (captured, opens toward +X)
+                        translate([FACE_D - NUT1420_H, 0, (CAM_H + 6)/2])
+                            rotate([0, 90, 0])
+                                cylinder(d = (NUT1420_AF + NUT_POCKET_EXTRA) / cos(30),
+                                         h = NUT1420_H + e, $fn = 6);
+
+                        // 1/4-20 bore through full face depth
+                        translate([-e, 0, (CAM_H + 6)/2])
+                            rotate([0, 90, 0])
+                                cylinder(d = NUT1420_BORE, h = FACE_D + 2*e);
+                    }
+    }
+}
+
+// ─────────────────────────────────────────────────────────────
+// Render selector
+// ─────────────────────────────────────────────────────────────
+if (RENDER == "bracket") {
+    realsense_bracket();
+
+} else if (RENDER == "assembly") {
+    color("LightGray", 0.9)    realsense_bracket();
+
+    // Camera body outline
+    translate([ARM_LEN, 0, ARM_H/2])
+        rotate([0, TILT, 0])
+            translate([FACE_D, -CAM_W/2, -(CAM_H/2 + 3)])
+                color("DimGray", 0.6)
+                    cube([CAM_D, CAM_W, CAM_H]);
+}

chassis/rplidar_mount.scad

@@ -0,0 +1,76 @@
+// ============================================================
+// rplidar_mount.scad — RPLIDAR A1M8 Anti-Vibration Ring  Rev A
+// Agent: sl-mechanical   2026-02-28
+// ============================================================
+// Flat ring sits between platform and RPLIDAR A1M8.
+// Anti-vibration isolation via 4× M3 silicone grommets
+// (same type as FC vibration mounts — Ø6 mm silicone, M3).
+//
+// Bolt stack (bottom → top):
+//   M3×30 SHCS → platform (8 mm) → grommet (8 mm) →
+//   ring (4 mm) → RPLIDAR bottom (threaded M3, ~6 mm engagement)
+//
+// RENDER options:
+//   "ring"       print-ready flat ring (default)
+//   "assembly"   ring in position on platform stub
+// ============================================================
+
+RENDER = "ring";
+
+// ── RPLIDAR A1M8 ─────────────────────────────────────────────
+RPL_BODY_D  = 70.0;          // body diameter
+RPL_BC      = 58.0;          // M3 mounting bolt circle
+
+// ── Mount ring ───────────────────────────────────────────────
+RING_OD     = 82.0;          // outer diameter (RPL_BODY_D + 12 mm)
+RING_ID     = 30.0;          // inner cutout (cable / airflow)
+RING_H      =  4.0;          // ring thickness
+
+BOLT_D      =  3.3;          // M3 clearance through-hole
+GROMMET_D   =  7.0;          // silicone grommet OD (seat recess on bottom)
+GROMMET_H   =  1.0;          // seating recess depth
+
+$fn = 64;
+e   = 0.01;
+
+// ─────────────────────────────────────────────────────────────
+module rplidar_ring() {
+    difference() {
+        cylinder(d = RING_OD, h = RING_H);
+
+        // Central cutout
+        translate([0, 0, -e])
+            cylinder(d = RING_ID, h = RING_H + 2*e);
+
+        // 4× M3 clearance holes on bolt circle
+        for (a = [45, 135, 225, 315]) {
+            translate([RPL_BC/2 * cos(a), RPL_BC/2 * sin(a), -e])
+                cylinder(d = BOLT_D, h = RING_H + 2*e);
+        }
+
+        // Grommet seating recesses — bottom face
+        for (a = [45, 135, 225, 315]) {
+            translate([RPL_BC/2 * cos(a), RPL_BC/2 * sin(a), -e])
+                cylinder(d = GROMMET_D, h = GROMMET_H + e);
+        }
+    }
+}
+
+// ─────────────────────────────────────────────────────────────
+// Render selector
+// ─────────────────────────────────────────────────────────────
+if (RENDER == "ring") {
+    rplidar_ring();
+
+} else if (RENDER == "assembly") {
+    // Platform stub
+    color("Silver", 0.5)
+        difference() {
+            cylinder(d = 90, h = 8);
+            translate([0, 0, -e]) cylinder(d = 25.4, h = 8 + 2*e);
+        }
+    // Ring floating 8 mm above (grommet gap)
+    color("SkyBlue", 0.9)
+        translate([0, 0, 8 + 8])
+            rplidar_ring();
+}

chassis/sensor_head.scad

@@ -0,0 +1,161 @@
+// ============================================================
+// sensor_head.scad — Sensor Head Platform  Rev A  2026-02-28
+// Agent: sl-mechanical
+// ============================================================
+// Clamps to 25 mm OD vertical stem (top of mast).
+// Platform hosts:
+//   • RPLIDAR A1M8       — centred, topmost
+//   • RealSense D435i    — front arm, 10° down tilt
+//   • 4× IMX219 cameras  — radial arms, 90° apart, 10° down
+//
+// RENDER options:
+//   "assembly"       3-D exploded-ish view (default)
+//   "collar_front"   front collar half for slicing (print 2)
+//   "collar_rear"    rear collar half for slicing
+//   "platform_2d"    flat projection → DXF
+// ============================================================
+
+RENDER = "assembly";
+
+// ── Stem ─────────────────────────────────────────────────────
+STEM_OD   = 25.0;            // actual stem OD (mm)
+STEM_BORE = 25.4;            // collar bore (+ 0.4 mm clearance for FDM)
+
+// ── Collar ───────────────────────────────────────────────────
+COL_OD     = 52.0;           // outer diameter
+COL_H      = 36.0;           // height
+COL_BOLT_X = 19.0;           // M4 clamping bolt CL from stem axis
+COL_BOLT_D = 4.5;            // M4 clearance hole
+COL_NUT_W  = 7.0;            // M4 hex nut A/F
+COL_NUT_H  = 3.4;            // M4 hex nut thickness
+
+// ── Platform ─────────────────────────────────────────────────
+PLAT_OD    = 120.0;          // octagonal platform, across-flats ≈ OD
+PLAT_H     =   8.0;          // plate thickness
+PLAT_Z     = COL_H;          // platform bottom sits atop collar
+
+// ── RPLIDAR bolt circle ───────────────────────────────────────
+RPL_BC      = 58.0;          // M3 hole bolt circle diameter
+RPL_HOLE_D  =  3.3;          // M3 clearance
+RPL_RECESS_D = 72.0;         // alignment lip diameter (body + 2 mm clearance)
+RPL_RECESS_H =  1.5;         // recess depth
+
+// ── Sensor arm attachment holes ───────────────────────────────
+// RealSense arm: 2× M4 holes at X = +ARM_R, Y = ±ARM_DY_RS
+ARM_R       = 50.0;          // radial distance from stem CL
+ARM_DY_RS   = 18.0;          // half-spacing for RealSense pair
+// IMX219 arms: 4 × 2 M4 holes at each 90° cardinal, tangential offset ±ARM_DY_CAM
+ARM_DY_CAM  =  9.0;          // half-spacing for IMX219 pair
+
+ARM_HOLE_D  =  4.5;          // M4 clearance
+
+$fn = 64;
+e   = 0.01;
+
+// ─────────────────────────────────────────────────────────────
+// collar_half(side)
+//   side = "front" (+Y) | "rear" (-Y)
+//   Print flat-face-down (mating face on build plate).
+// ─────────────────────────────────────────────────────────────
+module collar_half(side = "front") {
+    difference() {
+        // ── Body: D-shaped half-cylinder ─────────────────────
+        intersection() {
+            cylinder(d = COL_OD, h = COL_H);
+            translate([-COL_OD/2, (side == "front") ? 0 : -COL_OD/2, 0])
+                cube([COL_OD, COL_OD/2, COL_H]);
+        }
+
+        // ── Stem bore ────────────────────────────────────────
+        translate([0, 0, -e])
+            cylinder(d = STEM_BORE, h = COL_H + 2*e);
+
+        // ── M4 clamping bolt clearance holes (Y direction) ───
+        for (bx = [-COL_BOLT_X, COL_BOLT_X]) {
+            translate([bx, (side == "front") ? COL_OD/2 : 0, COL_H/2])
+                rotate([90, 0, 0])
+                    cylinder(d = COL_BOLT_D, h = COL_OD/2 + e);
+        }
+
+        // ── M4 hex nut pockets (rear half only) ──────────────
+        if (side == "rear") {
+            for (bx = [-COL_BOLT_X, COL_BOLT_X]) {
+                translate([bx, -(COL_OD/4 + e), COL_H/2])
+                    rotate([90, 0, 0])
+                        cylinder(d = COL_NUT_W / cos(30), h = COL_NUT_H + e, $fn = 6);
+            }
+        }
+
+        // ── M4 set screw — height / rotation lock (front half) ─
+        if (side == "front") {
+            translate([0, COL_OD/2, COL_H * 0.72])
+                rotate([90, 0, 0])
+                    cylinder(d = COL_BOLT_D, h = COL_OD/2 - STEM_BORE/2 + e);
+        }
+    }
+}
+
+// ─────────────────────────────────────────────────────────────
+// platform()
+// ─────────────────────────────────────────────────────────────
+module platform() {
+    difference() {
+        // ── Octagonal disc ───────────────────────────────────
+        cylinder(d = PLAT_OD, h = PLAT_H, $fn = 8);
+
+        // ── Stem passage ─────────────────────────────────────
+        translate([0, 0, -e])
+            cylinder(d = STEM_BORE, h = PLAT_H + 2*e);
+
+        // ── RPLIDAR alignment recess (top face) ──────────────
+        translate([0, 0, PLAT_H - RPL_RECESS_H])
+            cylinder(d = RPL_RECESS_D, h = RPL_RECESS_H + e);
+
+        // ── RPLIDAR M3 bolt holes — 58 mm BC ─────────────────
+        for (a = [45, 135, 225, 315])
+            translate([RPL_BC/2 * cos(a), RPL_BC/2 * sin(a), -e])
+                cylinder(d = RPL_HOLE_D, h = PLAT_H + 2*e);
+
+        // ── RealSense arm M4 holes — front (+X), ±ARM_DY_RS ──
+        for (dy = [-ARM_DY_RS, ARM_DY_RS])
+            translate([ARM_R, dy, -e])
+                cylinder(d = ARM_HOLE_D, h = PLAT_H + 2*e);
+
+        // ── IMX219 arm M4 holes — 4 × cardinal, ±ARM_DY_CAM ─
+        // Tangential perpendicular for angle a: (sin(a), -cos(a))
+        for (a = [0, 90, 180, 270])
+            for (s = [-1, 1])
+                translate([
+                    ARM_R * cos(a) + s * ARM_DY_CAM * sin(a),
+                    ARM_R * sin(a) - s * ARM_DY_CAM * cos(a),
+                    -e
+                ])
+                    cylinder(d = ARM_HOLE_D, h = PLAT_H + 2*e);
+
+        // ── Lightening pockets — between arm attachment holes ─
+        for (a = [45, 135, 225, 315])
+            translate([(PLAT_OD/2 - 22) * cos(a),
+                       (PLAT_OD/2 - 22) * sin(a), -e])
+                cylinder(d = 20, h = PLAT_H + 2*e);
+    }
+}
+
+// ─────────────────────────────────────────────────────────────
+// Render selector
+// ─────────────────────────────────────────────────────────────
+if (RENDER == "assembly") {
+    color("SkyBlue", 0.9)      collar_half("front");
+    color("DodgerBlue", 0.9)   mirror([0, 1, 0]) collar_half("rear");
+    color("Silver", 0.85)      translate([0, 0, PLAT_Z]) platform();
+
+} else if (RENDER == "collar_front") {
+    collar_half("front");
+
+} else if (RENDER == "collar_rear") {
+    collar_half("rear");
+
+} else if (RENDER == "platform_2d") {
+    projection(cut = true)
+        translate([0, 0, -(PLAT_Z + PLAT_H / 2)])
+            platform();
+}

chassis/sensor_head_assembly.md

@@ -0,0 +1,157 @@
+# SaltyBot Sensor Head — Assembly Diagram
+**Rev A — 2026-02-28 — sl-mechanical**
+
+---
+
+## Overview
+
+The sensor head mounts on top of the 25 mm OD vertical stem.
+Five printed/machined parts stack on a split collar platform.
+
+---
+
+## TOP VIEW (schematic)
+
+```
+                         FRONT (+X)
+                            ↑
+              [IMX219 arm]  |  [IMX219 arm]
+                  90°       |       0°
+                  ↑    +---------+    ↑
+                  |    |         |    |
+    [IMX219]←----[•]---| RPLIDAR |---[•]----→[IMX219]
+      270°        |    |  Ø70mm  |    |         90°
+                  ↓    |         |    ↓
+                       +---------+
+                       |  PLAT   |
+                       | Ø120mm  |
+                       | (octag) |
+                       +---------+
+                  ↑    |         |    ↑
+      [RS arm]---[•]---| COLLAR  |---[•]
+                       |  Ø52mm  |
+                       +---------+
+                            |
+                         25mm stem
+                            ↓
+```
+
+---
+
+## SIDE VIEW (section through front, to scale)
+
+```
+  Z
+  ↑
+  │
+  │   RPLIDAR A1M8 (Ø70 × 30 mm)
+  │  ┌────────────────────┐ ← Z ≈ 52 mm (top of RPLIDAR)
+  │  │  ██████████████    │
+  │  │  ██  A1M8  ██    │ ← Z ≈ 22 mm (bottom of RPLIDAR)
+  │  └────────────────────┘
+  │       │    │    │    │   ← M3×30 bolts (4 off)
+  │  ┌────┴────┴────┴────┐
+  │  │  rplidar_ring.scad│ ← Z = 14..18 mm  (4 mm ring)
+  │  │   [silicone gromm]│ ← grommets 8 mm below ring
+  │  └───────────────────┘
+  │  ┌───────────────────┐
+  │  │   P L A T F O R M │ ← Z = 36..44 mm
+  │  │  (octag, Ø120mm)  │
+  │  └───────────────────┘
+  │       │ COLLAR │
+  │  ┌────┴────────┴────┐
+  │  │  COLLAR FRONT    │ ← Z = 0..36 mm
+  │  │  │ stem bore │   │
+  │  │  COLLAR REAR     │
+  │  └──────────────────┘
+  │          │
+  │     25 mm STEM
+  └─────────────────────────────────────── X
+```
+
+> **Note on Z references:** Z=0 is the bottom of the collar.
+> Stem clamp bolts lock the sensor head at chosen height on the mast.
+
+---
+
+## IMX219 Arm (side view — one arm shown)
+
+```
+  Platform edge                          Camera PCB
+      │                                      │
+ ─────┤══════════════════════════════════════╗
+      │  ←── 52 mm arm ──────────────────►  ║  IMX219
+ ─────┤══════════════════════════════════════╝ ← 10° nose down
+      │ 2× M4                          4× M2
+      │ base bolts                     PCB bolts
+      │ [slot: CSI ribbon through arm length]
+```
+
+---
+
+## RealSense Arm (side view)
+
+```
+  Platform edge
+      │ 2× M4
+ ─────┤
+      │  Base       ←── 75 mm arm ──────────────────►
+ ─────┤  plate
+      │  (flat)     ══════════════════════════════════╗
+                                                      ║ ← 10° nose down
+                                                      ║  D435i
+                                                      ║  90×25×25
+                                                 1/4-20 nut (captured)
+```
+
+---
+
+## Assembly Sequence
+
+| Step | Action |
+|------|--------|
+| 1 | Print 2× `collar_half` (flat-face-down; mirror one in slicer) |
+| 2 | Print 1× `platform` |
+| 3 | Print 1× `rplidar_ring` |
+| 4 | Print 1× `realsense_bracket` |
+| 5 | Print 4× `imx219_arm` (one per direction) |
+| 6 | Seat 4× M3 silicone anti-vibration grommets in platform holes |
+| 7 | Place rplidar_ring on grommets; pass 4× M3×30 SHCS from platform bottom up through ring |
+| 8 | Set RPLIDAR A1M8 on ring; tighten M3×30 into RPLIDAR tapped holes (fingertight) |
+| 9 | Thread 1/4-20 hex nut into realsense_bracket pocket; bolt D435i onto bracket |
+| 10 | Bolt realsense_bracket to platform front with 2× M4×16 SHCS |
+| 11 | Bolt 4× imx219_arm to platform with 2× M4×16 SHCS each |
+| 12 | Snap IMX219 PCBs onto arm face plates with 4× M2×6 BHCS each |
+| 13 | Route CSI ribbon cables through arm slots toward platform centre |
+| 14 | Assemble collar halves around stem (flat faces mating); tighten M4×30 clamping bolts |
+| 15 | Tighten M4 set screw in front collar half to lock height |
+| 16 | Torque RPLIDAR M3 bolts: 0.5 N·m |
+
+---
+
+## Fastener Summary
+
+| Qty | Size | Use |
+|-----|------|-----|
+| 2 | M4×30 SHCS | Collar clamping bolts |
+| 1 | M4×10 set screw | Collar height / rotation lock |
+| 2 | M4×16 SHCS | RealSense bracket to platform |
+| 8 | M4×16 SHCS | IMX219 arms to platform (2 per arm) |
+| 4 | M2×6 BHCS | IMX219 PCB to face plate (per arm; ×4 arms = 16 total) |
+| 4 | M3×30 SHCS | RPLIDAR ring to platform (through grommet) |
+| 4 | M3 anti-vibration grommet | Silicone, M3, Ø6 | Between platform and RPLIDAR ring |
+| 1 | 1/4-20 hex nut | Captured in RealSense bracket |
+| 2 | M4 hex nut | Captured in collar rear half |
+| 8 | M4 flat washer | Under head of all M4 bolts |
+
+---
+
+## Print Settings
+
+| Part | Material | Infill | Perimeters | Notes |
+|------|----------|--------|-----------|-------|
+| collar_half (×2) | PETG | 40% | 5 | Flat-face-down; print support-free |
+| platform | PETG or PLA | 30% | 4 | Top-face-up |
+| rplidar_ring | PETG | 30% | 3 | Flat |
+| realsense_bracket | PETG | 35% | 4 | Base on bed; arm horizontal |
+| imx219_arm (×4) | PETG or PLA | 30% | 3 | Flat, arm along X |