Hazardous environment robot

Hazardous environment robot – definition

A hazardous environment robot is a mobile robotic system designed or adapted to collect data, inspect assets, or perform remote tasks where human access involves unacceptable safety, health, or operational risk. In mobile robotics, this usually means an unmanned ground vehicle (UGV) operating near environmental hazards rather than a robot that is automatically certified for every hazardous area.

The term must be separated from formal compliance status. A UGV may be used for remote inspection in a hazardous location without being rated for explosive atmospheres, water immersion, high radiation, or functional safety. Certification depends on the identified hazard, the applicable regulation, the installed electrical equipment, enclosure design, cable entries, batteries, and the complete robot configuration.

ISO 12100:2010 defines a risk-reduction process based on hazard identification, risk estimation, and risk reduction. For mobile robots, this process applies to the full system: base platform, payload, sensors, compute unit, power supply, communication link, and operating procedure. A camera or LiDAR mounted on a UGV can introduce additional ignition, ingress-protection, thermal, electromagnetic-compatibility, or mechanical risks.

Hazard classes relevant to UGV deployments

A hazardous environment is not a single technical category. The relevant engineering requirements depend on the actual exposure and on whether the robot must enter the hazardous zone or only observe it from a safe distance.

Hazard class	Typical UGV scenario	Engineering implications
Explosive atmosphere	Inspection near flammable gas, vapour, or combustible dust	Equipment intended for use in a classified explosive atmosphere must meet applicable requirements, such as the IEC 60079 series or, in the European Union, the relevant ATEX requirements. Standard consumer electronics, exposed connectors, fans, and batteries cannot be assumed suitable.
Dust and water ingress	Construction-site inspection, agriculture, tunnels, wet utility areas	Enclosure protection should be evaluated using IEC 60529 IP ratings. An IP code does not certify explosive-atmosphere suitability.
Thermal or chemical exposure	Hot surfaces, corrosive vapours, contaminated process areas	Material compatibility, battery temperature limits, sensor window contamination, and cable-jacket resistance must be specified.
Restricted or unstable terrain	Excavations, rubble, slopes, confined plant rooms	Mobility, traction, rollover risk, stop functions, communication-loss behaviour, and recovery procedures must be assessed and defined.

For explosive atmospheres, IEC 60079-0 (current edition IEC 60079-0:2026, which replaced the 2017 edition) specifies general requirements for equipment intended for use in explosive atmospheres. It is not sufficient to label an ordinary ROS 2 UGV as “ATEX-ready” or “intrinsically safe” without evidence for the complete assembled system.

Hazardous-environment UGV architecture

A practical hazardous-environment robot separates safety-critical functions from mission software where possible. ROS 2 is useful for perception, navigation, logging, and teleoperation, but ROS 2 itself is not a functional-safety certification framework. Its DDS-based middleware supports distributed communication, while system-level safety still requires a documented safety concept and validated hardware behaviour.

A typical architecture includes the following layers:

Mobility layer: motor drivers, wheel encoders, braking or stop behaviour, current monitoring, and a hardware watchdog.
Safety layer: emergency stop, power isolation, speed limits, loss-of-link behaviour, and operator procedures.
Perception layer: LiDAR, depth camera, RGB camera, IMU, GNSS/RTK receiver, gas sensor, thermal camera, or radiation detector.
ROS 2 layer: state estimation, mapping, navigation, remote visualisation, diagnostics, bag recording, and mission logic.
Communications layer: Wi-Fi, Ethernet, cellular, mesh radio, or tether, with explicit handling of latency and connection loss.

For coordinate frames, ROS applications normally follow REP 105. A ground robot publishes transforms between map, odom, and base_link. The map frame represents a globally consistent reference, while odom should remain locally continuous. This distinction is important when a robot loses GNSS reception or when SLAM corrects accumulated drift.

# Inspect essential ROS 2 interfaces during a remote UGV test
ros2 topic echo /diagnostics
ros2 topic echo /odom
ros2 topic hz /scan
ros2 run tf2_ros tf2_echo odom base_link

ROS 2 data interfaces and monitoring

Hazardous-environment missions require traceable telemetry. ROS 2 message types should be selected according to the sensor interface and recorded with timestamps. Message rate, delay, packet loss, covariance, and transform availability are measurable operational parameters, not assumptions.

ROS 2 interface	Common message type	Purpose
2D LiDAR scan	`sensor_msgs/msg/LaserScan`	Obstacle detection, local costmaps, 2D SLAM
IMU	`sensor_msgs/msg/Imu`	Orientation, when provided, angular velocity, and linear acceleration
GNSS position	`sensor_msgs/msg/NavSatFix`	Geographic position and covariance
Robot state estimate	`nav_msgs/msg/Odometry`	Pose and velocity estimate in a defined frame
Health reporting	`diagnostic_msgs/msg/DiagnosticArray`	Battery, temperature, sensor, communication, and controller status

Sensor data alone does not make a UGV autonomous. Navigation requires calibrated sensor extrinsics, valid TF transforms, a collision model, local obstacle handling, speed constraints, and a tested fallback state. In many hazardous deployments, supervised teleoperation with remote perception is more appropriate than fully autonomous navigation.

Leo Rover and Raph Rover in hazardous-environment projects

Leo Rover can be used as a research and prototyping UGV for remote sensing, ROS 2 navigation experiments, and inspection workflows. According to the Leo Rover technical documentation, the platform uses a Raspberry Pi compute unit, supports ROS 2 Humble or newer, has four-wheel differential drive, and carries an IP55 rating. IEC 60529 defines IP5X as protection against dust ingress in quantities that could interfere with satisfactory operation or impair safety, and IPX5 as protection against water jets projected from any direction.

IP55 does not mean dust-tight, waterproof, submersible, explosion-proof, or intrinsically safe. A Leo Rover configuration with external LiDAR, USB cameras, battery packs, antennas, or exposed connectors must be assessed as a complete system. It should not be deployed inside a classified explosive atmosphere unless the complete configuration has appropriate documented compliance.

Raph Rover is a larger UGV platform intended for projects requiring greater payload capacity. It can be a better mechanical starting point when a mission needs multiple protected sensor enclosures, a larger compute payload, or additional power-distribution hardware. Its larger capacity does not itself establish environmental certification, terrain safety, or autonomous-operation safety.

Key engineering controls and limitations

Before field deployment, the engineering team should document hazards and define measurable acceptance criteria. This avoids treating ROS 2 navigation performance as a substitute for safety validation.

Define the zone classification, exposure duration, temperature range, contaminants, and access restrictions.
Verify enclosure ratings, connector sealing, cable glands, battery protection, and payload compatibility.
Test emergency stop and communication-loss behaviour with the actual payload installed.
Set conservative speed and stopping-distance limits for the terrain and robot mass.
Record sensor streams, diagnostics, TF data, and operator commands with ros2 bag for post-mission analysis.
Maintain a manual recovery plan for immobilisation, rollover, blocked sensors, or loss of power.

Normative references and technical sources

The following references define the terminology and interfaces commonly used when engineering a hazardous-environment UGV.

ISO 12100:2010 – Safety of machinery – General principles for design – Risk assessment and risk reduction.
IEC 60079-0:2026 – Explosive atmospheres – Part 0: Equipment – General requirements.
IEC 60529 – Degrees of protection provided by enclosures (IP Code).
REP 105 – Coordinate Frames for Mobile Platforms.
ROS 2 Humble documentation – ROS 2 concepts, interfaces, tools, and middleware documentation.
Leo Rover documentation – Platform-specific hardware and ROS 2 integration information.

Hazardous environment robot