chassis/sim7600x_mount.scad
Platform bracket for Waveshare SIM7600X-H 4G HAT (65×56 mm,
RPi HAT M2.5 pattern 58×49 mm). Standoffs height = HAT underside
component clearance + 4 mm. Three walls (X−, X+, Y+); Y− edge
fully open for SIM card tray access without disassembly. Floor-plate
notch wider than SIM slot so card inserts/ejects with board in situ.
USB port notch same open edge. u.FL pigtail exit slot in Y+ wall.
4× M3 flat-head countersunk holes for base plate bolt-down.
RENDER: bracket / assembly / bracket_2d (DXF for base plate layout).
chassis/antenna_mount.scad
Two bracket types on shared 25 mm stem split-collar (M4 bolts,
set screw height lock, cable-tie grooves on rear half):
lte_bracket() — arm with 2× SMA bulkhead holes (6.6 mm clearance,
hex-nut capture on underside). u.FL pigtail relief grooves on arm
underside. Antennas point skyward. Recommended: 500–600 mm stem.
gnss_platform() — upward-facing tray (≤40×40 mm patch antenna),
4-sided retention lip, central GNSS coax slot, optional M2 bolt-down
holes at 30×30 mm. Mount as high as practical for clear sky view:
750–800 mm stem height. Recommended: active 35×35 mm patch antenna.
RENDER "full_stem" shows both at 80 mm spacing on stem stub.
Individual RENDER modes for each printable piece.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Protects expensive sensors when robot tips over during testing.
Files added:
chassis/bumper_frame.scad — roll cage (25 mm stem collar + 4 inclined
posts + crown ring + TPU snap pad). Posts at
45/135/225/315° between cameras. Crown at
Z=148 mm above cage collar, 18 mm above RPLIDAR
top. RPLIDAR FOV unobstructed.
chassis/base_bumper.scad — clip-on bumper ring for 270×240 mm base plate.
50 mm tall, 15 mm standoff, rounded corners.
4× corner + 4× side clip brackets. TPU snap
edge caps. FC status LEDs remain visible.
chassis/stem_protector.scad — split TPU sleeve for 25 mm stem. Snap-fit
closure (no hardware). Install 3–4 sleeves
along stem at ~200 mm intervals.
chassis/bumper_BOM.md — full BOM, print settings, install heights,
mass estimate (~500 g total, balanced).
All parts print without supports. Fully removable (clip/snap/clamp).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
ARCHITECTURE CHANGE: batteries no longer sit flat on the base plate.
They mount VERTICALLY on a central mast via a height-adjustable carousel.
CG is tuned by sliding the carousel up/down the stem.
Part A — prototype_baseplate.scad (Rev C):
- PLATE_DEPTH: 210mm → 130mm (no battery footprint constraint)
- Removed all battery tray geometry (holes, strap slots, expansion mounts)
- Added central stem socket: Ø38.6mm bore + 4x M5 flange bolt holes on Ø66mm BC
- Added stem_flange() module: laser-cut ring (qty 2, one each side of plate)
- Wiring pass-through slots flanking stem centre
- FC mount relocated to FC_X_OFFSET = -40mm (front of plate, clear of stem)
- New RENDER="stem_flange_2d" DXF export option
Part B — stem_battery_clamp.scad (new):
- Collar: two 3D-printed D-shaped halves, split at Y=0
- Ø38.6mm bore (1.5" EMT / 6061-T6 tube)
- 4x M6 clamping bolts + hex nut pockets
- 1x M6 set screw per half for height/rotation lock
- Arm attachment pads with M4 through-holes + nut pockets
- Arms: flat bars, laser-cut or printed, ARM_REACH=55mm
- Battery cradles: U-channel, open top, Velcro strap slots at 30% + 65% height
- BATT_COUNT param: 2 (180°), 3 (120°), or 4 (90°) radial batteries
- ARM_START_ANGLE chosen per BATT_COUNT to keep all arms clear of Y=0 split
- Battery ghosts in assembly for visualisation
- Full RENDER control: assembly / collar_half / arm / arm_2d / cradle
- Assembly sequence + CG tuning notes in file footer
BOM.md → Rev C:
- Part A table updated (5 laser-cut parts + stem tube)
- Part B table added (collar halves, arms, cradles, fasteners)
- Battery section: flat-deck layout replaced with vertical stem guide
- Fastener table updated to match new architecture
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Adds prototype_baseplate.scad — a laser-cuttable / CNC-routable flat
base plate for the self-balancing robot using caliper-verified axle
dimensions from the wiki (replaces placeholder values in PR #7):
Axle base dia: 16.11 mm (was 14 mm)
D-cut OD: 15.95 mm (new)
D-cut flat chord: 13.00 mm (new)
Total protrusion: 65.50 mm
Bearing seat OD: 37.80 mm
Tire OD: 254 mm (10x2.125")
Axle CL height: 127 mm (was wrong 310 mm)
Design:
- Single flat plate (6 mm Al / 8 mm acrylic), 680x220 mm blank
- Open fork slots (16.51 mm, semicircular tip) at each axle end
- Bearing seat relief cutout prevents Ø37.8 mm collar binding on edge
- Two-piece dropout clamp: lower (round bore) + upper (D-cut bore)
- D-cut profile computed from chord geometry with 0.3 mm all-round clearance
- MAMBA F722S FC holes (30.5x30.5 mm M3), battery mount holes (M4)
- Lightening slots, corner radii via minkowski
- RENDER param switches between 3-D assembly and 2-D DXF projections
for each of the three laser-cut parts
Updates BOM.md to Rev B: measurement delta table, prototype BOM section,
updated motor entry with verified axle spec.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
