Manufacturing & Quality Control

Document Version: MQC v2.0 Classification: Production Engineering Date: November 2025 Purpose: Quality control procedures and manufacturing standards for GROOT FORCE

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Table of Contents

1. QC Philosophy & Standards
2. Incoming Material Inspection (IMI)
3. In-Process Quality Control (IPQC)
4. Functional Testing Protocols
5. Final Quality Assurance (FQA)
6. Burn-In & Reliability Testing
7. Calibration & Metrology
8. Defect Classification & Handling
9. Documentation & Traceability
10. Continuous Improvement Systems

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QC Philosophy & Standards

1.1 CORE QUALITY PRINCIPLES

Zero-Defect Mindset Every GROOT FORCE unit leaving the factory must meet specification. No compromises.

Quality Gates Production flows through 7 mandatory quality gates. Failure at any gate stops the line.

Traceability Every component, every process step, every test result is logged and traceable to individual serial numbers.

Continuous Feedback Test failures feed directly back to engineering and suppliers within 24 hours.

1.2 APPLICABLE STANDARDS

ISO 9001:2015 — Quality Management Systems IPC-A-610 Class 2 — PCB Assembly Acceptability IEC 62368-1 — Safety of Audio/Video Equipment IEC 60825-1 — Laser Safety (Class 1) UN38.3 — Battery Transport Safety RoHS / REACH — Material Compliance IPC/WHMA-A-620 — Cable & Wire Harness Assemblies

1.3 ACCEPTANCE CRITERIA HIERARCHY

Critical Defects — Zero Tolerance

• Battery safety failures
• Thermal runaway risk
• Display misalignment >0.10mm
• Camera focus failure
• Firmware boot failure
• Structural cracks Result: Automatic rejection + root cause analysis

Major Defects — <0.3% Acceptance Quality Level (AQL)

• Sensor drift beyond calibration range
• Audio distortion >3%
• Cosmetic damage visible at 30cm
• IP54 seal compromise Result: Rejection + supplier notification

Minor Defects — <1.5% AQL

• Slight color variation in frame
• Packaging imperfections
• Minor surface finish variations Result: Review for acceptance or rework

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INCOMING MATERIAL INSPECTION (IMI)

2.1 PURPOSE Verify all incoming components meet specification before entering production. Prevent defective parts from contaminating the manufacturing line.

2.2 INSPECTION FREQUENCY

Critical Components (100% Inspection):

• Lithium battery cells
• Micro-OLED displays
• Camera modules
• SoC/SoM boards
• Magnesium spine castings

Standard Components (AQL Sampling):

• Resistors, capacitors (Level II, AQL 1.0)
• Connectors (Level II, AQL 0.65)
• Screws, fasteners (Level I, AQL 2.5)
• Packaging materials (Level II, AQL 2.5)

2.3 BATTERY CELL INSPECTION (100%)

Visual Inspection: □ No dents, punctures, or deformation □ No swelling or bloating □ Clean terminals, no corrosion □ Manufacturer markings legible □ Date code within 6 months

Electrical Testing: □ Open circuit voltage: 3.7V ±0.05V □ Internal resistance: <50 mΩ @ 1kHz □ Self-discharge: <3% over 24h □ Capacity verification: Sample 1 per 100 (full charge/discharge cycle)

Safety Verification: □ PCM functional test (charge cutoff @ 4.25V) □ PCM functional test (discharge cutoff @ 2.8V) □ NTC temperature sensor: 10kΩ @ 25°C ±1% □ Short circuit protection test

Documentation: □ UN38.3 test report verification □ IEC 62133-2 compliance certificate □ Manufacturer batch certificate □ Date codes logged in MES system

Rejection Criteria:

• Any visual damage - 100% lot rejection
• Voltage out of spec - 100% lot rejection
• PCM failure - 100% lot rejection
• Missing certificates - Hold pending documentation

2.4 DISPLAY MODULE INSPECTION (100%)

Visual Inspection (Under Magnification 10x): □ No dead pixels (0 tolerance) □ No bright spots or stuck pixels □ No dust or particles inside optical path □ No scratches on waveguide surface □ Optical coatings intact □ Frame alignment within tolerance

Optical Testing: □ Brightness uniformity: >90% across panel □ Color accuracy: ΔE <3 (sRGB) □ Contrast ratio: >1000:1 □ Response time: <20ms □ Viewing angle: 85° minimum FOV maintained

Electrical Testing: □ MIPI DSI signal integrity check □ Power consumption @ full white: <600mW per eye □ Backlight driver output: 3.3V ±5% □ I²C communication verified

Alignment Testing: □ Display mounting: ±0.08mm tolerance □ Focal distance: 2.5m ±0.2m □ Optical axis alignment: ±0.5° maximum deviation

Documentation: □ Supplier calibration certificate □ Binning grade verification (Premium grade required) □ Serial number logged

Rejection Criteria:

• Any dead/stuck pixels - Reject
• Brightness variation >10% - Reject
• Alignment out of tolerance - Reject

2.5 CAMERA MODULE INSPECTION (Sampling: 100%)

Visual Inspection: □ Lens clean, no scratches, no dust □ Mechanical housing intact □ Flex cable undamaged □ Focus mechanism smooth (if adjustable)

Optical Resolution Test: □ Resolution chart test: >80% MTF @ Nyquist □ Corner sharpness: >70% of center □ Distortion: <2% □ Vignetting: <15% corner falloff

Image Quality: □ Focus across full depth range verified □ Color reproduction accurate □ HDR capability verified □ Low light performance: ISO 3200 usable □ Video stabilization functional (if applicable)

Electrical: □ MIPI CSI signal clean □ Power consumption <250mW idle, <600mW active □ I²C communication stable

Documentation: □ Calibration data file present □ Manufacturing batch logged

Rejection Criteria:

• Focus failure - Reject
• Dead/hot pixels >5 - Reject
• Resolution <spec - Reject

2.6 SoC/SoM MODULE INSPECTION

Visual: □ No physical damage □ Solder joints clean □ Proper labeling and markings

Electrical (Sample Test Rig): □ Boot sequence successful □ All interfaces functional (USB, MIPI, I2C, SPI, UART) □ CPU stress test: stable under load □ GPU benchmark: meets minimum FPS □ NPU inference test: 30+ FPS on YOLOv8n □ Thermal performance: <85°C under sustained load □ RAM test: 0 errors □ Storage test: read/write verified

Firmware: □ Bootloader version correct □ Factory firmware flashed □ Secure boot keys verified

Rejection Criteria:

• Boot failure - Reject entire batch + supplier investigation
• Interface failure - Reject
• Thermal >90°C - Reject

2.7 MAGNESIUM SPINE CASTING

Dimensional Inspection (CMM): □ Length: ±0.05mm tolerance □ Width: ±0.03mm tolerance □ Thickness: ±0.02mm tolerance □ Mounting hole positions: ±0.05mm □ Surface flatness: <0.05mm deviation

Visual: □ No cracks (dye penetrant test on sample) □ No porosity or voids (X-ray on sample) □ Surface finish: Ra <1.6 μm □ No sharp edges or burrs

Material Verification (Sample per Batch): □ Alloy composition: AZ31B or AZ91D verified □ Hardness: 50-70 HV □ Corrosion resistance coating: >48h salt spray test

Thermal Conductivity Test (Sample): □ Thermal conductivity: >150 W/m·K verified

Rejection Criteria:

• Dimensional out of tolerance - Reject + return to supplier
• Cracks detected - 100% batch rejection
• Material composition wrong - 100% batch rejection

2.8 IMI WORKFLOW & DOCUMENTATION

Receiving:

1. Material received - Log in ERP system
2. Quarantine area - QC inspector notified
3. Random sampling (or 100% for critical items)
4. Inspection performed per checklist
5. Results logged in MES system with photos
6. Accept - Move to production storage
7. Reject - Quarantine + supplier notification + RMA process

Documentation Required:

• Supplier COC (Certificate of Conformance)
• Test reports (electrical, mechanical, optical)
• Material certificates (RoHS, REACH, conflict minerals)
• UN38.3 for batteries
• IPC certification for PCBs

Inspection Records:

• Date/time of inspection
• Inspector name/ID
• Lot number / batch code
• Sample size
• Test results (pass/fail per criterion)
• Photos of defects (if any)
• Disposition (accept/reject/hold)

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IN-PROCESS QUALITY CONTROL (IPQC)

3.1 PURPOSE Monitor production quality at critical process steps. Detect and correct issues before they propagate downstream.

3.2 IPQC INSPECTION POINTS

Station 1: PCB Assembly Inspection Station 2: Battery Pack Assembly Inspection Station 3: Frame & Spine Integration Station 4: Hinge Flex Routing Inspection Station 5: Display Installation & Alignment Station 6: Camera Module Installation Station 7: Final Assembly Pre-Test

3.3 STATION 1: PCB ASSEMBLY INSPECTION

Timing: After SMT + Wave Soldering, Before Functional Test

Visual Inspection (100% AOI + Manual Verify): □ No missing components □ No tombstoning (0 tolerance) □ No bridging between pads □ No cold solder joints □ Correct component orientation (polarity marks) □ No flux residue or contamination □ Proper fiducial marks present

Automated Optical Inspection (AOI): □ Component placement accuracy: ±0.05mm □ Solder joint classification: IPC-A-610 Class 2 □ Pad coverage: 75% minimum

X-Ray Inspection (BGA/QFN packages, Sample 5%): □ No voids in solder joints >25% □ Proper solder wetting □ No misalignment

Electrical Test (100%): □ Flying probe test: shorts and opens check □ Power supply rail check: all voltages within ±5% □ Ground continuity verified □ High-speed trace impedance spot-check (sample)

Rework Allowance:

• 1st pass yield target: >97%
• Maximum rework per board: 2 components
• No rework on BGA or fine-pitch ICs
• Reworked boards flagged in MES system

Rejection Criteria:

• Shorts/opens detected - Rework (if <2 components) or scrap
• Missing components - Reject
• Contamination - Rework cleaning + re-inspect

Documentation:

• AOI report with images
• X-ray images (for sample)
• Electrical test results logged with board S/N

3.4 STATION 2: BATTERY PACK ASSEMBLY

Timing: After Cell Welding, Before Integration

Visual Inspection (100%): □ Tab welds clean and solid □ No weld spatter on cell surface □ PCM board soldered correctly □ NTC sensor positioned correctly and secured □ Polyfuse installed with correct rating □ Wire insulation intact, no exposed copper □ Heatshrink tubing applied properly □ Connector seated fully

Weld Quality (Sample 10%): □ Pull test: >5N minimum tensile strength □ Resistance measurement: <10 mΩ across weld

Electrical Testing (100%): □ Open circuit voltage: 3.7V ±0.1V per cell □ Pack voltage: 3.7V (1S config) or 7.4V (2S config) ±0.2V □ PCM cutoff test: Charge stops @ 4.25V □ PCM cutoff test: Discharge stops @ 2.8V □ NTC reading: 10kΩ @ 25°C ±1% □ Polyfuse continuity verified

Safety Testing (Sample 5%): □ Short circuit protection verified (500ms disconnect) □ Overcharge protection verified □ Over-discharge protection verified □ Thermal cutoff verified (>60°C disconnect)

Polarity Check: □ Positive terminal marked clearly □ Connector orientation verified

Rejection Criteria:

• Weld failure - Scrap pack + investigate process
• PCM failure - Scrap pack
• Voltage out of spec - Scrap pack
• NTC failure - Scrap pack

Documentation:

• Cell batch number + date code
• Weld parameters logged
• Electrical test results with pack S/N
• Safety test results (for sample)

3.5 STATION 3: FRAME & SPINE INTEGRATION

Visual Inspection (100%): □ Magnesium spine seated properly in TR90 frame □ Graphite thermal pad installed correctly □ No gaps between spine and frame □ Overmolded joints smooth, no flash □ Hinge mechanism smooth (no binding) □ Screw torque correct: 0.5 N⋅m ±10% □ No visible stress cracks in frame

Dimensional Check (Sample 10%): □ Frame width: ±0.5mm tolerance □ Temple length: ±0.5mm tolerance □ Bridge width: ±0.3mm tolerance □ Hinge alignment: ±0.5mm (left to right symmetry)

Mechanical Testing (Sample 5%): □ Hinge flex test: 100 cycles min (pass if no damage) □ Frame twist test: 15° twist (pass if no permanent deformation) □ Drop test: 1.0m drop onto hard surface (pass if no cracks)

Rejection Criteria:

• Spine not seated - Rework
• Cracks in frame - Scrap
• Hinge binding - Rework (lubricate and adjust)
• Dimensional out of tolerance - Rework or scrap

3.6 STATION 4: HINGE FLEX ROUTING INSPECTION

Visual (100%): □ FPC routed cleanly through hinge channel □ No sharp bends (bend radius >3mm) □ No twisting or kinking □ FPC connector seated and locked □ Strain relief applied correctly □ Overmold completed with no voids

Electrical Continuity (100%): □ All traces tested: <1Ω resistance end-to-end □ No shorts between adjacent traces □ High-speed differential pairs: impedance within ±10%

Flex Cycle Test (Sample 10%): □ 500 flex cycles @ 90° bend □ Electrical continuity maintained throughout □ No visible damage to FPC after cycling

Rejection Criteria:

• Continuity failure - Rework FPC or scrap unit
• Sharp bends - Rework routing
• Flex test failure - Scrap + investigate FPC supplier

3.7 STATION 5: DISPLAY INSTALLATION & ALIGNMENT

Critical Process — Highest Precision Required

Visual (100%, Under Microscope): □ Display seated flush in housing □ No dust or particles on display surface □ No scratches on waveguide □ Adhesive applied evenly (no gaps, no overflow) □ Optical axis centered

Alignment Measurement (100%, CMM or Vision System): □ Horizontal alignment: ±0.05mm tolerance □ Vertical alignment: ±0.08mm tolerance □ Rotational alignment: ±0.4° tolerance □ Inter-pupillary distance (IPD): 63mm ±2mm adjustable range □ Focal plane: 2.5m ±0.2m (collimation test)

Optical Testing (100%): □ No light leakage around edges □ Brightness uniformity: >90% □ No distortion at edges of FOV □ Proper image focus across FOV □ No double images or ghosting

User Comfort Test (Sample 10%): □ Display visible without eye strain □ Text legible at typical reading distance □ No excessive brightness causing discomfort □ IPD adjustment smooth and stable

Rejection Criteria:

• Alignment out of tolerance - Rework (remove and reinstall)
• Optical defects - Scrap display + replace
• Dust contamination - Rework cleaning + re-inspect

THIS IS THE MOST CRITICAL QC POINT Display misalignment = poor user experience = product failure Zero compromises allowed

3.8 STATION 6: CAMERA MODULE INSTALLATION

Visual (100%): □ Camera seated flush and secure □ Lens clean (no fingerprints, dust) □ Flex cable routed without stress □ Connector locked properly □ Alignment marks matched

Image Quality Test (100%): □ Focus test chart: Sharp across frame □ Resolution: >80% MTF maintained □ No vignetting >15% □ Exposure correct □ White balance accurate □ Video stream stable (no dropped frames)

Alignment to Display (Sample 10%): □ Camera optical axis aligned with display overlay □ AR registration test: virtual objects stable and accurate □ Passthrough mode: low latency <20ms

Rejection Criteria:

• Focus failure - Replace camera module
• Resolution degraded - Replace module
• Alignment off - Rework positioning

3.9 STATION 7: FINAL ASSEMBLY PRE-TEST

Visual (100%): □ All external screws torqued correctly □ No gaps in housing □ Nose pads attached securely □ Earhooks/temples aligned □ Branding/logos applied correctly □ Serial number engraved and legible

Fit and Finish (Sample 10%): □ Frame sits level on flat surface □ Temple arms open and close smoothly □ No rattling or loose parts □ Weight balanced (no tipping) □ All edges smooth (no sharp points)

Pre-Functional Checklist: □ Battery pack installed and connected □ All FPC connectors locked □ All sensor modules seated □ Firmware pre-loaded □ Ready for functional test

Rejection Criteria:

• Missing parts - Rework (install missing parts)
• Poor fit/finish - Rework or scrap
• Loose components - Rework (secure properly)

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FUNCTIONAL TESTING PROTOCOLS

4.1 PURPOSE Verify all electronic, optical, and mechanical functions operate correctly before final QA.

4.2 FUNCTIONAL TEST STATION OVERVIEW

Test Station Components:

• Automated test fixture with pogo pins
• Power supply (adjustable 3.0-4.2V, 3A)
• MIPI DSI/CSI test interface
• I2C/SPI/UART protocol analyzer
• Thermal camera
• Environmental chamber (optional, for sampling)
• Calibrated light source (for display testing)
• Anechoic box (for audio testing)
• Test software (custom LabVIEW or Python)

Test Duration: 8-12 minutes per unit

4.3 POWER-ON SEQUENCE TEST

Objective: Verify device boots correctly and all power rails stable

Procedure:

1. Connect device to test fixture (pogo pins to charge contacts)
2. Apply 3.7V power
3. Monitor boot sequence via UART debug port
4. Verify power rail voltages: □ 3.3V rail: 3.3V ±3% □ 1.8V rail: 1.8V ±3% □ 1.2V rail: 1.2V ±3% □ 5.0V rail (USB): 5.0V ±5%
5. Monitor boot time: <15 seconds to OS ready

Pass Criteria:

• All power rails within tolerance
• Boot completes successfully
• No error messages in boot log
• Boot time <15 seconds

Fail Criteria:

• Voltage out of range - Check PMIC, rework if needed
• Boot failure - Check SoM, flash firmware, retest

• 3 fails - Scrap + root cause analysis

4.4 DISPLAY FUNCTIONAL TEST

Objective: Verify display shows correct images with proper brightness and color

Procedure:

1. Display test pattern sequence: a. Full white (brightness test) b. Full black (contrast test) c. RGB primary colors (color accuracy) d. Checkerboard pattern (pixel uniformity) e. Moving text (refresh rate and latency)
2. Measure brightness: Center of display with calibrated photometer
   • Target: 1000-1200 nits
3. Check for dead/stuck pixels (automated vision system)
4. Check ambient light sensor (ALS) response:
   • Dim light - Low brightness
   • Bright light - High brightness

Pass Criteria:

• Brightness: 1000-1200 nits ±10%
• Zero dead/stuck pixels
• Color accuracy: ΔE <5
• ALS responds correctly (brightness adjusts)

Fail Criteria:

• Brightness out of range - Check display driver, rework if needed
• Dead/stuck pixels - Replace display
• ALS failure - Check sensor, replace if needed

4.5 CAMERA FUNCTIONAL TEST

Objective: Verify cameras capture images with correct quality

Procedure:

1. Capture test image of calibrated resolution chart
2. Analyze image quality: □ Resolution: >80% MTF @ Nyquist □ Focus: Sharp across frame □ Exposure: Histogram centered □ White balance: Correct color temperature
3. Video test: Capture 10-second clip, verify no dropped frames
4. Low-light test: Capture image in dim environment (20 lux) □ Image must be usable, noise acceptable

Pass Criteria:

• Resolution meets spec
• Focus correct
• Exposure correct
• Video stable (no frame drops)
• Low-light usable

Fail Criteria:

• Resolution <spec - Replace camera module
• Focus failure - Rework alignment or replace module
• Exposure failure - Check firmware calibration, reflash if needed

4.6 SENSOR SUITE TEST

Objective: Verify all sensors respond correctly to stimuli

IMU (9-Axis) Test:

1. Device placed on calibrated tilt platform
2. Rotate device through known angles:
   • 0°, 45°, 90°, 180°
3. Read gyro, accelerometer, magnetometer outputs
4. Verify readings within ±2% of expected values

ToF Sensor Test:

1. Place calibrated target at known distances:
   • 10cm, 50cm, 100cm, 200cm
2. Read ToF distance measurements
3. Verify accuracy: ±3cm or ±3% (whichever is greater)

LiDAR Test:

1. Place calibrated target at known distances:
   • 1m, 5m, 10m
2. Read LiDAR distance measurements
3. Verify accuracy: ±5cm @ 10m

Environmental Sensor (BME688) Test:

1. Verify temperature, humidity, pressure readings
2. Compare to reference sensor in test chamber
3. Accuracy: ±0.5°C, ±3% RH, ±1 hPa

Health Sensors (MAX30102 + MLX90614):

1. Verify heart rate sensor detects pulse (test jig with simulated finger)
2. Verify SpO2 reading >95% with test jig
3. Verify infrared temp sensor reads 36-38°C on calibrated surface

Pass Criteria:

• All sensors respond correctly
• Readings within tolerance

Fail Criteria:

• Sensor out of tolerance - Recalibrate in software, if still failing - Replace sensor board
• Sensor non-responsive - Check connections, replace if needed

4.7 AUDIO FUNCTIONAL TEST

Objective: Verify bone conduction speakers and microphones work correctly

Speaker Test:

1. Play calibrated audio tone (1kHz, 500Hz, 4kHz)
2. Measure SPL with test microphone on simulated head
   • Target: 80-85 dB SPL @ 10cm
3. Frequency response test:
   • 200Hz-8kHz response within ±6dB
4. Check for distortion:
   • THD <3% @ 80dB SPL

Microphone Test:

1. Play calibrated sound from test speaker
2. Record audio via device microphones
3. Analyze recording:
   • Frequency response: 100Hz-8kHz flat ±6dB
   • SNR: >55dB
4. Beamforming test (if applicable):
   • Verify voice pickup from front, rejection from rear

Pass Criteria:

• SPL within range
• Frequency response acceptable
• Distortion <3%
• Microphone records clearly

Fail Criteria:

• No sound - Check audio driver IC, replace if needed
• Distortion high - Check speaker alignment, replace if needed
• Microphone failure - Replace microphone

4.8 WIRELESS CONNECTIVITY TEST

Objective: Verify Bluetooth, Wi-Fi, and optional LTE connections

Bluetooth Test:

1. Device pairs with test smartphone
2. Audio streaming test (play music, verify quality)
3. RSSI measurement: >-70 dBm @ 5m
4. Latency test: <150ms audio latency

Wi-Fi Test:

1. Connect to test access point (2.4GHz and 5GHz)
2. Throughput test: >20 Mbps download, >10 Mbps upload
3. RSSI: >-65 dBm @ 5m
4. Ping test: <50ms to gateway

Optional LTE Test (Enterprise Models):

1. Insert test SIM
2. Connect to test network
3. Data session established
4. Throughput: >5 Mbps

Pass Criteria:

• Connections established successfully
• Throughput meets spec
• RSSI acceptable

Fail Criteria:

• No connection - Check antenna, reflow solder if needed
• Low throughput - Check RF tuning, rework if needed
• RSSI too low - Check antenna placement, rework if needed

4.9 THERMAL PERFORMANCE TEST

Objective: Verify device does not overheat under load

Procedure:

1. Run stress test (CPU + GPU + AI inference)
2. Monitor temperatures with thermal camera:
   • CPU/SoC die temp
   • Battery surface temp
   • Frame surface temp (user contact points)
3. Run for 30 minutes
4. Verify temperatures within limits:
   • CPU: <85°C
   • Battery: <45°C
   • Frame surface: <38°C (skin contact limit)

Pass Criteria:

• All temperatures within limits
• No thermal throttling (or only at expected load)
• Thermal derating firmware functional (if triggered)

Fail Criteria:

• CPU >90°C - Check thermal paste, rework if needed
• Battery >50°C - Investigate power draw, check for short circuit
• Frame surface >40°C - Check thermal path, rework if needed

4.10 FIRMWARE & SOFTWARE TEST

Objective: Verify firmware and OS boot correctly and functions work

Procedure:

1. Verify firmware version matches production release
2. Boot to OS (Android or Ubuntu)
3. Launch test app (automated test suite)
4. Test app verifies: □ All system services running □ All sensors accessible □ Display renders correctly □ Camera app launches and captures □ Audio playback and recording □ Bluetooth and Wi-Fi functional □ AI runtime loads and responds □ Battery level reported correctly
5. OTA update test (sample 5%):
   • Trigger test OTA update
   • Verify update installs correctly
   • Verify rollback works if update fails

Pass Criteria:

• All tests pass
• No crashes or errors
• OTA functional (if tested)

Fail Criteria:

• Test app fails - Investigate, reflash firmware, retest
• OTA failure - Check update server, retry

4.11 FINAL FUNCTIONAL TEST REPORT

Each device generates:

• Test log file (XML or JSON)
• Serial number
• Date/time of test
• Test station ID
• Pass/fail status for each test
• Measured values (voltages, brightness, etc.)
• Firmware version
• Operator ID

Data uploaded to MES system for traceability

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FINAL QUALITY ASSURANCE (FQA)

5.1 PURPOSE Perform comprehensive final inspection before packaging. This is the last check before device ships to customer.

5.2 FQA INSPECTION CHECKLIST (100%)

Visual Inspection: □ No scratches, dents, or cosmetic defects □ All logos and markings correct and legible □ Serial number engraved correctly □ Color/finish matches specification □ All accessories included (cable, cloth, manual) □ Packaging intact and sealed

Functional Spot-Check: □ Power on successfully □ Display shows test image clearly □ Audio plays test tone □ Bluetooth pairs with test device □ Battery charges (connector test)

Comfort and Fit: □ Device sits comfortably on test mannequin head □ Weight balanced (no tipping) □ No sharp edges or uncomfortable pressure points □ Nose pads and ear hooks aligned

Packaging: □ Device placed correctly in foam insert □ All accessories included and secured □ QC pass label applied □ Box sealed with tamper-evident tape

5.3 RANDOM SAMPLING TESTS (AQL 0.65)

From each production lot (500 units):

• Sample 50 units (10%)
• Perform extended testing: □ 4-hour battery life test □ Extended thermal test (2 hours load) □ Drop test (1.2m onto hard surface) □ Water resistance test (IPX4 spray) □ Hinge flex test (1000 cycles)

If >3 units fail: Stop production, investigate

5.4 FQA PASS/FAIL CRITERIA

Pass:

• All visual inspection items OK
• All functional tests pass
• No critical or major defects
• Minor defects <1.5% (acceptable within AQL)

Fail:

• Any critical defect - Automatic rejection
• Major defects >0.3% - Reject lot
• Minor defects >1.5% - Reject lot

Rejected units sent to rework station or scrap

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BURN-IN & RELIABILITY TESTING

6.1 PURPOSE Detect early-life failures (infant mortality) before shipping to customers. Accelerate aging to expose weak components.

6.2 BURN-IN PROTOCOL

Frequency: 100% of units (or sample per batch depending on volume)

Procedure:

1. Fully charge device
2. Place in burn-in rack (temperature-controlled chamber)
3. Set chamber to 45°C ±2°C
4. Power on device
5. Run stress test script:
   • CPU @ 80% load
   • GPU rendering test pattern
   • Display @ 100% brightness
   • Sensors active
   • Bluetooth and Wi-Fi active
6. Run for 8-12 hours
7. Monitor for failures:
   • Device crashes
   • Overheating
   • Display failures
   • Battery failures

Pass Criteria:

• Device runs without failure for 8-12 hours
• Temperature stable <50°C
• Battery discharges normally (no sudden drops)
• No system crashes

Fail Criteria:

• System crash - Investigate, reflash firmware, retest
• Overheating - Investigate thermal path, rework if needed
• Battery failure - Replace battery, retest

• 2 failures - Scrap unit

6.3 ACCELERATED LIFE TESTING (ALT) - SAMPLE ONLY

Purpose: Validate long-term reliability

Sample Size: 30 units per production batch (initial), reduce to 10 units/batch after process stable

Test Conditions:

• Temperature cycling: -10°C to 50°C, 10 cycles
• Humidity: 85% RH, 48 hours
• Vibration: 10G, 1 hour (simulates shipping)
• Drop test: 1.5m drop, 10 drops (higher than user spec)
• Salt spray: 48 hours (for corrosion resistance)

Expected Failure Rate:

• <2% failure across all tests
• If >2%: Investigate root cause, improve process

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CALIBRATION & METROLOGY

7.1 SENSOR CALIBRATION

All units require sensor calibration before final functional test.

IMU Calibration:

• 6-position calibration (device placed in 6 orientations)
• Software auto-calibrates gyro bias, accelerometer offset, magnetometer
• Calibration data stored in EEPROM
• Verification: Tilt device, verify readings accurate

ToF Calibration:

• Crosstalk calibration (measure with no target, subtract baseline)
• Offset calibration (measure known distance, calculate offset)
• Data stored in sensor SRAM (persistent)

Display Calibration:

• Color calibration (adjust RGB gain to match sRGB)
• Brightness calibration (adjust backlight driver)
• Gamma curve calibration
• Calibration data stored in display driver IC

Camera Calibration:

• Lens distortion calibration (capture calibration pattern, calculate distortion coefficients)
• Color calibration (measure color chart, adjust ISP settings)
• Calibration data stored in camera module flash

Audio Calibration:

• Frequency response calibration (measure speaker output, adjust EQ)
• Microphone gain calibration
• Calibration data stored in audio codec

7.2 CALIBRATION TOOLS & EQUIPMENT

• CMM (Coordinate Measuring Machine) for dimensional inspection
• Photometer for display brightness measurement
• Colorimeter for color accuracy
• Accelerometer reference for IMU calibration
• Distance measurement jig for ToF/LiDAR calibration
• Audio analyzer for speaker/mic calibration
• Thermal camera for temperature measurement

All tools must be calibrated annually by accredited lab (NATA/A2LA)

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DEFECT CLASSIFICATION & HANDLING

8.1 DEFECT CATEGORIES

Critical Defects (Zero Tolerance):

• Battery safety failures (short circuit, thermal runaway risk)
• Structural failures (cracks, breaks)
• Electrical shorts (fire hazard)
• Display misalignment (unusable product)
• Firmware boot failure (bricked device)

Action: Automatic scrap + root cause analysis + line stop

Major Defects (AQL 0.3%):

• Sensor failures
• Audio failures
• Camera focus failures
• Cosmetic damage visible at 30cm
• IP54 seal failures

Action: Reject + rework (if possible) or scrap

Minor Defects (AQL 1.5%):

• Slight color variations
• Packaging imperfections
• Software bugs (non-critical)

Action: Rework or accept (within AQL limits)

8.2 REWORK PROCESS

Rework Station:

• Dedicated area with trained operators
• ESD-safe workbenches
• Magnification and lighting
• Specialized tools (soldering, gluing, etc.)

Rework Limits:

• Maximum 2 rework cycles per unit
• No rework on BGA or critical ICs
• Reworked units flagged in MES system
• Reworked units get extended burn-in (24h)

8.3 SCRAP & FAILURE ANALYSIS

Scrapped units:

• Categorized by failure mode
• Sent to engineering for failure analysis
• Components harvested if possible (for spare parts)
• Data logged for continuous improvement

Failure Rate Targets:

• First Pass Yield (FPY): >95%
• Rework Rate: <3%
• Scrap Rate: <2%

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DOCUMENTATION & TRACEABILITY

9.1 LOT TRACEABILITY

Every component batch tracked:

• Battery cells: Lot number + date code
• Displays: Serial number + binning grade
• Cameras: Serial number + calibration date
• PCBs: Panel ID + SMT machine ID + date/time

Every device has unique serial number encoding:

• Production facility
• Production date
• Production line
• Sequence number

Serial number format: GF-YYMMDD-LINE-XXXX Example: GF-251120-A-0001 (Produced on Nov 20, 2025, Line A, Unit 0001)

9.2 MANUFACTURING EXECUTION SYSTEM (MES)

All data logged in MES:

• Component lot numbers
• Test results (pass/fail + measured values)
• Rework history
• Operator IDs
• Timestamps

MES provides:

• Real-time yield monitoring
• Defect analysis and Pareto charts
• Traceability queries (recall capability)
• SPC (Statistical Process Control) charts

9.3 QUALITY RECORDS RETENTION

Records kept for:

• Device lifetime + 7 years (minimum)
• Compliance with warranty requirements
• Support for field failure investigations

Records include:

• Incoming inspection reports
• In-process inspection reports
• Functional test reports
• Calibration certificates
• Burn-in test logs
• Final QA reports

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CONTINUOUS IMPROVEMENT SYSTEMS

10.1 KAIZEN & LEAN MANUFACTURING

Principles:

• Eliminate waste (time, materials, defects)
• Continuous small improvements
• Operator empowerment (suggest improvements)
• Visual management (andon boards)

Daily Gemba Walks:

• QC manager walks production line daily
• Observes processes
• Talks to operators
• Identifies improvement opportunities

10.2 ROOT CAUSE ANALYSIS (RCA)

Triggered by:

• Critical defects
• Yield drop >5% from baseline
• Customer complaints

Method: 5 Whys + Fishbone Diagram

Process:

1. Define problem clearly
2. Assemble cross-functional team
3. Brainstorm potential causes
4. Test hypotheses
5. Implement corrective actions
6. Verify effectiveness
7. Update procedures
8. Train operators

10.3 SUPPLIER QUALITY MANAGEMENT

Supplier Audits:

• Annual audits of critical suppliers
• Verify quality systems (ISO 9001)
• Verify process controls
• Review defect data

Supplier Performance Metrics:

• On-time delivery
• Defect rate (ppm)
• Responsiveness to issues

Supplier Development:

• Work with suppliers to improve quality
• Share defect data and trends
• Collaborative problem-solving

10.4 CUSTOMER FEEDBACK LOOP

Field failure data:

• Collected from warranty returns
• Analyzed for trends
• Fed back to engineering and manufacturing
• Used to improve process

NPS (Net Promoter Score):

• Track customer satisfaction
• Investigate low scores
• Continuous product improvement

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APPENDIX A: QC FORMS & CHECKLISTS

A.1 Incoming Material Inspection Report (Form IMI-001) A.2 PCB Assembly Inspection Checklist (Form IPQC-001) A.3 Battery Pack Inspection Checklist (Form IPQC-002) A.4 Display Alignment Checklist (Form IPQC-005) A.5 Functional Test Report (Form FT-001) A.6 Final QA Checklist (Form FQA-001) A.7 Burn-In Test Log (Form BI-001) A.8 Rework Authorization Form (Form RW-001) A.9 Non-Conformance Report (Form NCR-001) A.10 Corrective Action Request (Form CAR-001)

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APPENDIX B: CALIBRATION INTERVALS

Equipment Calibration Interval Standard

CMM 12 months ISO 10360 Photometer 12 months NIST traceable Colorimeter 12 months CIE standards Power supply 12 months IEC 60950 Multimeter 12 months NIST traceable Oscilloscope 12 months NIST traceable Thermal camera 12 months Factory calibration Audio analyzer 12 months IEC 60268 Torque wrench 6 months ISO 6789

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APPENDIX C: CONTACT INFORMATION

QC Manager: [Name] Email: qc@grootforce.com.au Phone: +61 XXX XXX XXX

Production Manager: [Name] Email: production@grootforce.com.au Phone: +61 XXX XXX XXX

Engineering: engineering@grootforce.com.au Supplier Quality: supplier-quality@grootforce.com.au

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DOCUMENT APPROVAL

Prepared by: QC Engineering Team Approved by: [Name], VP Operations Date: November 2025 Version: MQC v2.0 Next Review: May 2026

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END OF DOCUMENT