Mining / Underground — Technical Requirements for Inspection Robots

Research compiled: March 2026 | For: Drover Labs CEO

1. GPS-Denied Navigation (SLAM Requirements)

Underground mines have zero GPS coverage at any depth. This is the fundamental technical challenge that eliminates most commercial drones from consideration.

What's Required

• SLAM (Simultaneous Localization and Mapping) is mandatory
• LiDAR-based SLAM is the dominant approach (Emesent, Exyn both use 3D LiDAR SLAM)
• Must function beyond-visual-line-of-sight (BVLOS) with zero communications at times
• Must navigate without: GPS, WiFi, cellular, pre-loaded maps, or human pilot input
• All intelligence must be onboard — edge compute required

Current State of Art

• Exyn: Level 4A autonomy — no human intervention during flight, no prior maps
• Emesent: "Remote autonomy" — autonomous within a defined zone
• Both use rotating LiDAR (typically Velodyne, Ouster, or similar)
• Key metric: Exyn can cover 16 million cubic meters in a single flight at 2+ m/sec

Drover Requirements

• Need robust 3D SLAM that works in:
  • Dust-filled environments (reduces LiDAR range and creates false positives)
  • Narrow tunnels with parallel walls (LiDAR degeneracy issues)
  • Wide open stopes (up to 50m+ diameter voids)
  • Variable lighting (complete darkness to bright LED work lights)
• 360° camera coverage needs to be fused with LiDAR for visual inspection context
• Must maintain positional accuracy to at least ±0.1m for stope volume reconciliation

2. Explosive Atmosphere Certifications

This is the biggest regulatory blocker for aerial robots in coal mines and gassy metal mines.

Global Certification Standards

ATEX Group Classification

• Group I: Mining environments (underground coal, gassy metal mines)
• Group II: Above-ground industrial (refineries, chemical plants, etc.)

Critical issue for Drover: As of January 2025, there are NO fully ATEX-certified commercial drones. Flyability explicitly states this on their website. ANYbotics is targeting ANYmal X as the first ATEX quadruped (1H 2026 target).

What ATEX Certification Requires for a Robot

1. Intrinsically safe circuits — limit electrical energy below ignition threshold even in fault
2. Flameproof enclosures (Ex d) around electronics
3. Anti-static materials throughout
4. Surface temperature < 135°C (T4 class) maximum
5. IP65+ enclosure rating (dust and water)
6. Sealed propulsion systems for drones
7. Individual certification for every sensor, camera, and payload
8. Any hardware change (new sensor, software update) can require recertification
9. Certification process: 6–12 months, freezes hardware design

MSHA Requirements (US Underground Coal)

• Title 30 CFR specifies intrinsic safety requirements
• MSHA has NOT yet set specific guidelines for aerial vehicles underground
• De facto requirement: Class I Division 1 (no sparks, even from static discharge)
• The entire robot structure must be explosion-proof and capable of containing blast
• Academic research (2023, MDPI) confirms: "MSHA prohibits using drones in underground coal mines" without permissibility certification
• Source: https://www.mdpi.com/2504-446X/7/1/44

Strategic Implication for Drover

• Short term (0–2 years): Target non-gassy metal mines and underground construction tunnels where gas risk is lower — no ATEX required
• Medium term (2–4 years): Must achieve ATEX Group I certification to access coal and gassy mines — this opens the largest market segment
• Cost of ATEX development: ATEX equivalent robots cost 3–5× more than standard versions
• Annual maintenance: 10–15% of purchase price for explosion-proof variants

3. Environmental Challenges

Dust

• Coal dust: Explosive when airborne (primary concern for ignition)
• Silica dust: Constant in gold/silver/quartz mines — abrasive, settles on camera lenses
• Effect on sensors:
  • LiDAR: Scattering reduces range; false point cloud returns
  • Cameras: Lenses coat within minutes in active zones
  • Motors: Ingress causes premature failure
• Requirements:
  • IP65+ for all electronics (dust-tight, water-resistant)
  • Camera dome with anti-dust coating or periodic blast-clean mechanism
  • Sealed motor compartments

Water / Moisture

• Underground mines are inherently wet — water seeps through rock
• Standing water in drifts, water spray from drilling operations
• Requirement: IP65 minimum, IP67 preferred for ground-traversing robot
• ANYmal spec: IP67 (unique differentiator)

Rough Terrain

• Drift floors are uneven — blasted rock rubble, mud, rail tracks
• Slopes up to 15–20% grades in some mines
• Stopes: vertical voids, no floor at all (aerial only)
• UGV requirements:
  • Tracked or legged locomotion (wheels struggle in rubble)
  • Ground clearance of 15–20cm minimum
  • Able to traverse rail tracks embedded in floors

Temperature and Pressure

• Deep mines: temperature increases with depth (~1°C per 100m depth)
• Deep gold mines (South Africa/Australia): 50°C+ ambient at 3km depth
• Extreme environments require thermal management of electronics
• Operating range requirement: 0°C to 50°C ambient

Confined Spaces

• Typical drift width: 3–5m
• Ore passes: 1–2m diameter vertical shafts
• Robot must fit through access points and navigate narrow passages
• Flyability Elios 3: ~40cm footprint — sets a reference for tight-space access
• Key issue for hybrid UAV/UGV: both platforms must fit through same access hatches

4. Communication in Underground Environments

This is a severe constraint with major architectural implications.

Reality of Underground Comms

• No WiFi, no cellular coverage beyond a few meters from access points
• Some mines have deployed underground leaky-feeder (LF) radio systems
• Very few have underground WiFi mesh networks (expensive to deploy)
• Radio communications degrade around corners and in voids

Current Industry Approaches

• Leaky-feeder RF cable systems: Coax cable run through tunnels provides ~900 MHz radio coverage; range-limited to ~500m from cable
• Underground WiFi mesh: Being piloted by some tier-1 miners; range ~100m per node
• UWB (Ultra-Wideband): Used for personnel tracking; not suitable for data transfer
• Acoustic communication: Experimental only

What This Means for Robot Design

1. Must operate fully autonomously without real-time communication (missions launched, completed, robot returns)
2. Store-and-forward data model: All scan data stored onboard; uploaded when robot returns to charging/comms station at surface or drift portal
3. Emergency comms only: Low-bandwidth position beacon is acceptable; HD video streaming is NOT possible underground
4. Mission planning: Must pre-plan missions at surface with known 3D map; robot executes autonomously

Drover Architecture Implication

• Comms link to surface: NOT required for mission execution
• Data offload: At charging station (tethered or near-surface WiFi)
• Real-time monitoring: Not possible at depth — operator gets post-mission report
• This is consistent with how Exyn and Emesent operate (no real-time link required)

5. Sensor Requirements

Primary Sensors (Must Have)

Secondary Sensors (High Value)

Gas Detection Priority List (MSHA Critical Gases)

1. Methane (CH₄): Explosive above 5% LEL — primary risk in coal mines
2. Carbon Monoxide (CO): Toxic, produced by blasting, fire; MSHA limit 50 ppm
3. Hydrogen Sulfide (H₂S): Toxic at 1 ppm; present in sulfide ore mines
4. Oxygen (O₂): Deficiency (<19.5%) or enrichment (>23.5%) dangerous
5. Nitrogen Dioxide (NO₂): Produced by diesel engines and blasting

Note: Adding gas detection to the robot makes it a compliance tool, not just an inspection tool — dramatically increasing willingness to pay.

Data Output Requirements (What Mines Actually Need)

• Point cloud (.las or .e57 format): For volume reconciliation, CAD integration
• Orthorectified 360° video/imagery: For visual inspection documentation
• Change detection: Before/after blast comparison (week-to-week diff)
• Gas readings with spatial coordinates: Geo-referenced environmental data
• Export to mine planning software: Deswik, Vulcan, Datamine, Leapfrog

6. Operational Requirements

Flight/Run Time

• Industry reference: Exyn covers 16M m³ per flight
• Practical underground: 30–60 minute missions are typical
• Battery swap vs. charging station at portal: swap preferred for continuous ops

Payload Weight

• Mines are weight-sensitive for transport in cages/lifts
• Target: <25kg total system weight for one-person deployment
• Spot: ~32kg (heavy for tight access)
• Elios 3: <1kg drone (very light)

Deployment by Non-Expert

• Mining surveyor skill level: NOT a drone pilot
• Competitors aim for "one-button launch" (Exyn's stated goal)
• Training should take <1 day
• Critical for Drover RaaS: if customer needs to call Drover every time, unit economics break

Durability

• MTBF target: >500 flight hours before major maintenance
• Replaceable parts: propellers, landing gear, camera domes
• IP65+ standard

Interoperability

• Output must feed directly into existing mine software stacks
• Key platforms used by Tier 1 miners:
  • Deswik (mine planning, widely used in Australia/Canada)
  • Vulcan (Maptek — volumetrics, Australia dominant)
  • Datamine (global)
  • Leapfrog Geo (geological modeling)
  • OSIsoft PI (real-time data historian)
  • Bentley MicroStation (structural)