Several vehicle configurations will be analysed during the project – flying, climbing and crawling (snake-like) – to provide a means of obtaining information from areas of the mine rendered inaccessible due to an incident. The main vehicle features will be (1) the ability to move freely in the complex environments and adverse conditions such as rock fall, flooding and smoke, (2) adequate payload for several on-board sensors including visible & IR cameras, inertial measurement units, ELF force measurement systems, and communications, (3) long life batteries, (4) lightweight configuration for ease of transportation to the rescue area, and (5) the ability to collaborate with other similar robots in order to create a small swarm of vehicles to cover large areas of a mine in a reasonable time.
This type of vehicle, commonly known as a drone or UAV, has several advantages such as fast navigation and good rescue area observation. Moreover, its potential low cost makes it very suitable for the swarm configurations and substitution in the case of accidents. Nevertheless, its limited ability to autonomously fly in complex and confined rescue areas is its main drawback.
The main advantage of this kind of vehicle is its ability to climb in the rescue environment using special types of “legs” that allows it to walk on the ceiling or walls of the tunnels and also over rubble or parts of the mine’s supporting structure. There are several locomotion configurations such as four or six active legs, the locomotion control strategy being bio-inspired (e.g. ants). The attachment mechanism is the crucial issue: suction pumps, magnets and ever glue attachment (dragon-fly) options are possible depending on the environment. The suitability of these technologies is a key issue in this project.
For extremely complicated environments, snake-like locomotion is preferred. Such vehicles, comprising a high number of segments, have the advantage of being able to crawl over the rocks and even in flooded conditions. Moreover, due to the modular vehicle concept, segments can easily be added or removed, thereby reconfiguring the kinematics. The main drawback of this type of vehicle is the limited area knowledge which is limited to a local view only. An understanding of the global rescue scene, being complex, is sometimes not possible.
Combination of Vehicles
A combination of several types of vehicles will be also analysed. Combining vehicles with a high level of global situation understanding (flying) and vehicles with very local data (snake-like) could be very valuable. Conversely, careful attention will have be given to preventing poor standardisation of rescue vehicles, which could result from this approach, thereby making the overall control and maintenance more difficult.