Why this way.

Sensor Pod Family — Decision Log

Running log of decisions across Stages 0-10. Cites wandersensor_room_node_v1/ Blueprint bundle as the ideation source (preserved, not re-adopted as canonical).

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Stage 0: Feature-parity sweep (2026-04-24)

• Scope: presence detection + environmental sensing + smart-home integration across 7 SKUs
• Competitive set: Aqara FP1/FP2/FP2 Pro ($50-100) · Hue Motion ($40-50) · Eve Motion ($40) · Ikea Vallhorn ($15) · Ikea Parasoll ($10) · SwitchBot Motion ($20) · SONOFF SNZB-06P ($15) · Apollo MSR-2 ($30-50) · Everything Presence One/Lite ($50-85) · Shelly Plus H&T ($30) · Aqara TVOC ($40) · Eve Room ($100) · Airthings View Plus ($300) · Reolink/Ring outdoor PIR solar sensors
• Primary differentiator (unique): "Identity-free by design guarantee — no camera, no mic, no face-ID ever" enforced as Platform Standard 3 hard line; explicit in spec; every competing sensor roadmap trends toward more cameras, we guarantee fewer
• Secondary differentiators: mid-tier VOC+CO2+presence bundled ($69 vs $300 separate-product stack) · Matter-over-Thread at Micro scale · Outdoor+mmWave+LoRa+solar (no direct competitor at consumer price) · Ambassador-assembled · open-STL · 7-year parts · 60/30/10 Community Pool
• 15 LEADS / 10 MATCHES / 1 LAG per _COMPETITIVE-AUDIT-2026-04-24.md

Stage 1: Intake + freeze (2026-04-24)

• Ideation source: wandersensor_room_node_v1/ Blueprint bundle (single $63 node with ESP32-S3 + LD2450 + BME680 + US-100 + ATtiny85 co-processor + custom PCB + 3D-printed wedge), preserved as historical reference
• Decision: do NOT adopt the Blueprint BOM as-is. Blueprint's ATtiny85 co-processor + US-100 ultrasonic + BME680 combination is cluttered and adds unjustified complexity. Replace with clean architecture:
• Single MCU (ESP32-S3) handles all sensors directly; drop ATtiny85 co-processor (unnecessary)
• Drop US-100 ultrasonic (LD2450 24 GHz + PIR is the proven combo; ultrasonic adds noise and complexity)
• Upgrade BME680 → BME688 (latest gen, better VOC-index, pin-compatible)
• Add SHT41 as dedicated T/H (BME688 does T/H but SHT41 is more accurate for that specific measurement)
• Add SCD41 NDIR CO2 on Pro+ (photometric; the real game-changer)
• Family expansion: single Blueprint node → 7 SKUs (Room Std/Pro/Ultra, Door Std, Outdoor Std/Pro, Micro) addressing full market covering low-to-mid price points
• Device IDs: WV-SNS-ROOM-STD/PRO/ULT · WV-SNS-DOOR-STD · WV-SNS-OUT-STD/PRO · WV-SNS-MICRO
• Ship targets locked: Room Std/Pro + Door + Micro base: 2027-Q3 · Ultra: 2027-Q4 · Outdoor: 2028-Q1 · Micro: 2028-Q2
• Revision: v1.0-candidate

Stage 2: Component selection

MCU per tier:

• Room Node (all tiers) + Door Node + Outdoor Node: ESP32-S3 (WiFi + BLE + Thread via 802.15.4 radio; ample RAM for local processing + future expansion), Seeed XIAO ESP32-S3 or ESP32-S3-WROOM module
• Micro: ESP32-C6 (native Thread + BLE 5.0 + ultra-low-power sleep modes; smaller die; CR2032-compatible power profile), chosen for battery life priority

Presence sensor per tier:

• Room Std + Pro: HLK-LD2450 24 GHz mmWave (multi-target X/Y, up to 3 targets, UART 256000 baud per Blueprint spec)
• Room Ultra: LD2450 + Infineon BGT60LTR11AIP 60 GHz gesture + dual-band PIR (AM312 short + LHI968 wide) + MLX90640 thermopile 8×8
• Room Pro: LD2450 + AM312 PIR secondary (false-positive filtering)
• Door Std: LD2450 + STM VL53L5CX 8×8 time-of-flight (entry/exit direction)
• Outdoor Std: HLK-LD2410C 24 GHz (outdoor-optimized; better interference tolerance) + LHI968 PIR
• Outdoor Pro: LD2410C + 60 GHz + MLX90640 + (opt) camera add-in module (explicit off-by-default add-on)
• Micro: AM312 PIR only (radar omitted for the Micro price target + CR2032 battery life)

Environmental sensors:

• All tiers: SHT41 temp + humidity (±0.2°C / ±1.8% RH, Sensirion flagship)
• All tiers except Outdoor: TSL2591 light (lux) sensor
• Room Pro+: BME688 pressure + VOC-index gas (latest Bosch, DSP-enhanced VOC output)
• Room Pro+: SCD41 NDIR CO2 (Sensirion photometric; true CO2 vs eCO2 estimation)

Protocol stack:

• All tiers: Matter 1.3+ over Thread primary (via 802.15.4 radio on ESP32-S3 or ESP32-C6) + BLE commissioning
• Room + Door: WiFi 2.4 GHz fallback for commissioning + low-bandwidth reporting
• Outdoor: LoRa (RFM95W US915 / RFM96W EU868 region-variant) primary uplink; WiFi 2.4 commissioning-only

Power:

• Room + Door: USB-C + PoE (splitter) + CR2477 battery (for Room; Door is wired-only due to always-on counting)
• Outdoor: solar-ready (6V/2W Std, 6V/5W Pro) + 2× 18650 Li-ion (user-replaceable) + 12V DC input
• Micro: CR2032 only

Stage 3: Compatibility

• ESP32-S3 ↔ LD2450 UART: proven in the Blueprint node (256000 baud, GPIO-based hardware UART); validated by thousands of ESPHome deployments
• ESP32-S3 ↔ BME688 / SCD41 / SHT41 / TSL2591: all I2C; address-space check shows no conflicts (BME688 0x76/0x77, SCD41 0x62, SHT41 0x44, TSL2591 0x29)
• ESP32-S3 ↔ ThreadRadio (native 802.15.4): built-in on S3; no external coordinator needed; Matter 1.3 over Thread validated by Apollo + Everything Presence deployments
• Radio coexistence: Thread (2.4 GHz) + BLE (2.4 GHz) + WiFi 2.4 GHz, all share Silicon Labs style time-division on ESP32-S3; works but Thread throughput can degrade during heavy WiFi. Mitigation: once commissioned, disable WiFi, rely on Thread; WiFi is fallback only.
• Outdoor Node LoRa + WiFi simultaneous: LoRa 915 MHz + WiFi 2.4 GHz = completely different bands, no contention. Dual-radio supervision in ESP32-S3 supported.
• Ultra 60 GHz + 24 GHz + PIR + thermopile simultaneous: different sensing modalities, no conflict; thermal budget OK (max 350 mW sustained).
• Door Node ToF VL53L5CX + LD2450: VL53L5CX is 940 nm pulsed laser; LD2450 is 24 GHz radar, no optical/RF cross-talk. Shared power rail OK (VL53L5CX ~15 mA burst, LD2450 ~100 mA).
• Mechanical fit: Room Std/Pro fit in 50×40×18 mm wedge; Room Ultra needs 60×50×22 mm for 60 GHz + thermopile; Outdoor 90×90×35 mm puck; Micro 40×20×12 mm dongle.

Stage 4: Sourcing

• HLK-LD2450: Hi-Link direct ($8-12 per unit @ 1k); widespread AliExpress + Amazon availability; 🟡 Perplexity flagged lifecycle, monitor for successor (LD2451 rumored 2026-Q4)
• HLK-LD2410C: Hi-Link direct ($5-8 per unit @ 1k); outdoor-tested variant
• Infineon BGT60LTR11AIP: DigiKey catalog-active; $14-18 per unit @ 1k; 60 GHz gesture-ready
• BME688: Bosch / DigiKey + Mouser; $6-8 per unit @ 1k; catalog-active
• SHT41 / SCD41 / TSL2591: Sensirion / AMS, DigiKey + Mouser + Adafruit; all catalog-active
• MLX90640: Melexis / DigiKey / Adafruit; $35 per unit @ 1k; catalog-active
• VL53L5CX: STMicroelectronics / DigiKey; $18 per unit @ 1k
• AM312 / LHI968 PIR: commodity; AliExpress + Amazon + Adafruit; <$2 per unit
• RFM95W (LoRa): HopeRF / DigiKey / Mouser; $12 per unit @ 1k
• ESP32-S3-WROOM-1 module: Espressif / Mouser / DigiKey; $3-4 per unit @ 1k
• ESP32-C6-WROOM-1: Espressif / Mouser; $2.50-3 per unit @ 1k
• CR2477 / CR2032 batteries: Renata / Panasonic / DigiKey; $0.40 / $0.20 per unit
• 18650 Li-ion (Outdoor): LG MJ1 or Samsung 35E; $3-4 per unit via 18650batterystore or industrial distributor
• Solar panel (Outdoor): Voltaic 6V/2W or 6V/5W; $8-18 per unit
• Enclosures: 3D-printed PETG (prototype/low-vol) via Shapeways/Xometry ($1-3 per unit); injection-molded PC+ABS at scale (5k+ units with $12k tooling; ~$1.50/unit)
• Custom PCB: JLCPCB (prototype) + Sierra Circuits (mid-run US-origin for FCC positioning); 4-layer 60×40 mm ~$3 per board @ 1k

See SOURCING.csv for full vendor matrix.

Stage 5: DFM / DFA / DFT

• Room Std/Pro/Micro assembly: ~12-15 min Ambassador work per unit (module-based, drop-in-and-solder SMT headers, screw-to-chassis). Minimal hand-solder: PCBA from contract manufacturer is pre-populated; Ambassador does final integration + flash + test.
• Room Ultra: 20-22 min (extra modules for 60 GHz + thermopile + PIR pairs)
• Door Node: 15 min
• Outdoor Std/Pro: 20-28 min (IP65 sealing gasket + solar panel + LoRa antenna + battery integration)
• Micro multi-pack: hybrid line, SMT at CM, kitting by Ambassadors (bag + label + QC + pack-card)
• Test coverage: 8 tests per Room unit, 10 for Pro, 12 for Ultra, 10 for Door, 12 for Outdoor, 6 for Micro (battery + Thread + env read + enclosure seal)

Stage 6: Thermal / EMC

• Thermal: all tiers passive-cooled; worst case Room Ultra at 1.8W sustained well under any thermal cliff; PETG chassis handles 80°C+
• EMC:
• ESP32-S3 + LD2450 interaction in <1m proximity: both pre-certified; no re-test needed if chassis/layout follows reference
• LoRa + WiFi/Thread (Outdoor only): different bands, no coexistence issue
• 60 GHz Infineon (Ultra): separate band from 2.4 GHz cluster, no interference
• ESD Level 4 (IEC 61000-4-2) on USB-C + PoE + solar input (TVS diodes inline)
• FCC Part 15 B + C: inherited from pre-certified modules (ESP32-S3, LD2450, LD2410C, LoRa RFM95W, BME688, etc.); device-level test for assembled unit ~$3-5k per family variant
• SAR: not applicable (no cellular); 60 GHz Ultra is low-power exempt

Stage 7: Compliance

• FCC Part 15 B: device-level ~$3-5k per major family variant (Room, Door, Outdoor, Micro = 4 device-level tests); most radios inherited
• CE RED / UKCA: ~$3-5k per variant
• Matter 1.3+ cert (CSA) for occupancy + env sensor profiles: ~$5-8k first variant, $2-3k amortized for derivatives
• Thread Group cert: ~$3-5k family-level
• No FDA / no UL high-voltage work, all sensors are low-voltage battery/USB/PoE
• Outdoor: IP65 test ~$2-3k (IEC 60529)
• Outdoor: Solar panel safety: standard commercial solar 6V/5W panels are already safety-compliant
• Region variants for Outdoor + Micro (LoRa): US915 + EU868 + AU915 + AS923 = 4 cert variants for Outdoor + Micro LoRa tiers
• Cumulative cert budget family-wide v1.0: ~$65-95k (detail in COMPLIANCE.md)

Stage 8: Canonical BOM + GUIDE + STLs

See BOM-platform.csv, BOM-modules.csv, GUIDE.md, STL-OPEN-FILES/README.md.

Stage 9: HW ↔ FW binding

• Firmware: ESPHome-based custom WanderOS-Sensor layer
• Rationale: ESPHome is the proven open-source IoT firmware framework; HA integration is automatic via HA Discovery; we contribute upstream
• WanderOS-Sensor overlay adds: Matter 1.3+ commissioning, WanderVerse profile awareness, Ambassador-signature provisioning, identity-free enforcement (no camera/mic even if dev flashes custom code, hardware doesn't support it)
• OTA: ESPHome OTA via HTTPS from WanderNode Hub or user-configured update server
• Matter cluster implementation: OccupancySensing + TemperatureMeasurement + RelativeHumidityMeasurement + IlluminanceMeasurement + AirQuality (Pro+ CO2+VOC) + PressureMeasurement (Pro+)
• LoRa firmware (Outdoor): LoRaWAN 1.0.4 or ChirpStack direct; integration with WanderNode Hub LoRa concentrator, or WanderSafeMesh, the nonprofit community mesh (wanderingwithpride.org)
• Development cost: ~$180k (1 FTE firmware, 1 FTE Matter + HA integration, 0.5 FTE mobile companion app, 0.5 FTE QA) across 9 months

Stage 10: Gate review

EVT/DVT/PVT stages per GATE.md. Ship-target summary:

• 2027-Q3: Room Node Std + Pro + Door Node + (partial) Micro soft-launch
• 2027-Q4: Room Node Ultra
• 2028-Q1: Outdoor Std + Pro
• 2028-Q2: Micro full family (5-pack + 10-pack volumes)

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Critical decisions this session

#	Decision	Impact
1	Replace Blueprint's single $63 node with 7 SKUs covering low-to-mid price points	addresses full market instead of one form factor
2	Drop ATtiny85 co-processor + US-100 ultrasonic from Blueprint design	cleaner architecture, lower cost, fewer failure points
3	Add CO2 (SCD41) + BME688 to Pro+ for Airthings-parity at 1/4 the price	category-leading mid-tier environmental
4	**Identity-free by design** as non-negotiable Platform Standard 3 line, explicit in spec, baked into hardware (no camera/mic ICs on any board)	category-defining privacy posture
5	Matter 1.3+ over Thread as primary protocol every tier	Mode-2 industry-standard; Apple/Google/Samsung/HA direct pairing
6	Outdoor Pro's optional camera module is EXPLICITLY off-by-default and sold as separate SKU (m-outdoor-cam)	honors Standard 3 (Modular Consent) even on edge-case Pro feature
7	Micro multi-pack uses hybrid assembly (SMT at CM, Ambassador kitting)	reconciles the Micro price target with Standard 1 (supported-employment assembly)
8	LoRa as Outdoor primary uplink (not WiFi)	power budget + range (WiFi won't reach across a HAVEN property)
9	60 GHz mmWave on Ultra only (Infineon BGT60LTR11AIP)	gesture detection differentiator for premium tier
10	MLX90640 thermopile 8×8 as identity-free person/animal classifier	Outdoor Pro + Room Ultra get it; camera-free classification category
11	Apply dual-mode principle: Matter direct-pair standalone + WanderVerse-deep integration	any buyer can start standalone; ecosystem deepens without lock-in
12	7-yr parts for single-unit SKUs; 5-yr for Micro multi-pack	honors Standard 4 with batch-economics exception documented
13	Nonprofit subsidy pricing (2/3 of standard retail) across all tiers	WWP Mission Partner alignment
14	All tiers feed 60/30/10 Community Pool per Ambassador Program	consistent with Router/Hub/Band family
15	Open-STL enclosures for every SKU; STEP files for Std tier editable	repair culture, customization culture