Adjust to the eye.
A 160 mm rail, captured carriage, fore-aft setup slide and pitch clevis locate the carrier. The modeled lateral centre range is −48 to +48 mm; fore-aft adjustment is ±10 mm. Optical eye-box coverage must be measured.
The intelligence
behind the visor.
An optical-see-through display, a head-supported adjustable carrier, a local sensor node and a torso processor. AR-01 connects the human-facing display to the suit’s serviceable mechanical and electrical architecture.
IRON-DAD / D03 · INTERACTIVE GEOMETRY
Loading the actual mesh…
Choose a component to inspect its geometry. Motion is prescribed, not a physical simulation.
The selected architecture: retain the Monocle's bonded optical engine and locate it with a purpose-built carrier. This is a head-locked optical telemetry overlay, not a miniaturized HoloLens or six-degree-of-freedom spatial mapping. Helmet context uses an assumed eye datum; the allocated engine box is not a measured vendor-body model.
01 / AN OPTICAL SYSTEM NEEDS A STABLE DATUMThe helmet opens.
The helmet opens.
The optic stays located.
The rail follows the padded head interface, not the moving faceplate. The selected engine remains intact; the design changes its mount, not its bonded optics. External armor is not used to define the eye position.
Support the housing.
Leave the optic alone.
The open saddle uses compliant edge restraint around a conservative 52 × 26 × 34 mm engine allocation. That box is a design allowance—not an exact manufacturer reconstruction. No cutting, grinding or clamping optical faces.
Manual swing-away.
The drop link studies a 100° manual swing. Open the faceplate before moving the carrier. The local link clears its clevis in the recorded samples; a whole-helmet path and an enforced interlock are not yet validated.
02 / REAL PIXEL BUDGET, NOT A MOVIE-SCREEN PROMISEUseful information.
Useful information.
A quiet centre.
The selected engine publishes a 640 × 400 display and 20° field of view. This preview uses the actual pixel budget; it does not simulate lens aberrations, eye relief, brightness at the eye or angular calibration. Hardware reference ↗
SIMULATED INPUTS · 640 × 400 LAYOUT · HEAD-LOCKED OVERLAY · NO CAMERA OR MICROPHONE ACCESS
Executable display code.
The MicroPython application receives bounded, newline-framed telemetry, validates every field and draws the device-sized interface. Touch controls hide the overlay, adjust brightness and put the retained engine to sleep.
Unknown stays unknown.
Missing sensors appear as dashes. Lost or stale data removes the readings. Invalid packets and repeated sequence numbers do not refresh their age. No servo, retention or body-assistance command is accepted by the display protocol.
03 / SENSORS → VALIDATION → LIGHTLocal information.
Local information.
Independent access.
The wired sensor node feeds the torso host. A local BLE link carries only telemetry to the retained optical engine. The display is advisory; manual access and cooling do not depend on it.
HELMET / SENSOR NODEXIAO ESP32-C3SHT40 air temperature + humidity
3.3 V local I²C / USB serial
3.3 V local I²C / USB serial
→
TORSO / SERVICE BAYPi Zero 2 W hostPacket validation + freshness
Explicit device pairing / BLE data
Explicit device pairing / BLE data
→
VISOR / RETAINED ENGINEOptical-see-through HUD640 × 400 local display
Factory battery / off-head charging
Factory battery / off-head charging
Two paths.
No optic power hack.
The sensor node and host use a regulated 5 V accessory branch with independently specified protection. The optical engine retains its factory power arrangement. Charging occurs off the head; no worn charging or battery bypass is designed here.
An aperture is not tracking.
The retained engine's camera has a development opening, not a calibrated sight cone. Camera capture and microphone recording are off in the supplied application. Spatial anchors, navigation and person identification are not implemented.
04 / ROUTE AROUND THE HUMANServiceable channels.
Serviceable channels.
Nothing across the exit.
Use removable insulating channels behind the brow and along the side service route. Keep the neck connection accessible, preserve a tested service loop, and do not run cables across spring travel, padding pressure zones or release openings.
| Interface | Draft connection | Design rule |
|---|---|---|
| Local air sensor | D4 / GPIO6 → SDA D5 / GPIO7 → SCL 3V3 + GND → sensor | 3.3 V-compatible SHT40 breakout; local short I²C run. Confirm pull-ups and connector orientation. Do not apply 5 V to GPIO. |
| Helmet → torso | USB serial via node USB-C to host USB OTG | Strain relief on both carriers. Accessible disconnect, never a structural tether. Prove head-turn slack and avoid back-feeding a second power source. |
| Torso → optical engine | BLE raw-data service; whitelisted telemetry | No REPL or actuator command transport. Explicit device selection; application-level packet validation is not authenticated safety communication. |
| Accessory power | Protected regulated 5 V source → host + node branch | Fuse, cable, connector and converter ratings remain load-dependent selections. Bench current/temperature and fault checks precede wearable use. |
| Engine power | Original retained cell and manufacturer charging arrangement | No custom cell wiring, external-voltage injection, charge override or live charging while worn. |
Pin and board references: Seeed XIAO ESP32-C3 · Raspberry Pi Zero 2 W · Monocle API
05 / THE DESIGN IS CONCRETE. ITS LIMITS ARE TOO.Geometry now.
Geometry now.
Commissioning next.
15 manufactured CAD components, two reference envelopes, actual helmet aperture geometry, a display application, a serial-to-BLE bridge and sensor-node source. This is an engineered development package—not a claim that hardware has passed on-head testing.
Bench fit
Measure the retained engine, locate its eye box and prove the saddle does not load optical surfaces. Finalise retention hardware.
Helmet clearance
Establish actual eye and head datums, faceplate clearance, release reach and the complete swing-away path.
Optical checks
Verify clear direct view, image placement, glare, ghosting, brightness and comfort without assuming the preview is calibration.
Electrical checks
Measure consumption, radio performance inside metal, stale-data behaviour, cable movement, heat and reliable off-head charging.
AR-01 mechanics + firmware
STEP/STL, adjustable parameters, receiver, host bridge, sensor-node source and test evidence. Hardware execution and Arduino target compilation are not claimed.