Implementation of Explosion Safety Regulations in Design of a Mobile Robot for Coal Mines

Abstract

The article focuses on specific challenges of the design of a reconnaissance mobile robotic system aimed for inspection in underground coal mine areas after a catastrophic event. Systems that are designated for these conditions must meet specific standards and regulations. In this paper is discussed primarily the main conception of meeting explosion safety regulations of European Union 2014/34/EU (also called ATEX—from French “Appareils destinés à être utilisés en ATmosphères Explosives”) for Group I (equipment intended for use in underground mines) and Category M1 (equipment designed for operation in the presence of an explosive atmosphere). An example of a practical solution is described on main subsystems of the mobile robot TeleRescuer—a teleoperated robot with autonomy functions, a sensory subsystem with multiple cameras, three-dimensional (3D) mapping and sensors for measurement of gas concentration, airflow, relative humidity, and temperatures. Explosion safety is ensured according to the Technical Report CLC/TR 60079-33 “s” by two main independent protections—mechanical protection (flameproof enclosure) and electrical protection (automatic methane detector that disconnects power when methane breaches the enclosure and gets inside the robot body).

Designing and using robots for performing inspections in potentially explosive atmospheres

“…The need to carry out inspections in areas with danger of explosion that are difficult to access or dangerous to humans has led to the development of mobile robots for performing such tasks [15]. Performing inspections through the use of mobile robots must take place when the human factor cannot participate in such an activity due to the high explosion risks in the respective area [16]. In order to satisfy a large part of the industries in which there are Ex-classified areas, from the point of view of explosion protection the robots must be: -Independent: they are self-charging and require no human intervention -Reliability: they are designed to operate for months, or even years, without maintenance -Ruggedness: they can operate in a wide range of climates.…”

Special Feature on Advanced Mobile Robotics

“…New applications of mobile robots are available in an underground coal mine for explosion safety. Novák et al [59] investigated the safety regulations and practice solutions with tele-operated mobile robots. Zhang et al [60] argued that a robotic drilling task can be handled with a sliding mode control.…”

Simulation of motion of a mobile robot on uneven terrain

“…Inspection is another example of a task for mobile robots. Here, commonly, hybrid tracked chassis systems are used (Novák et al, 2018). It allows one to overcome obstacles such as stairs.…”