Abstract: The mine disaster brings a lot of economic losses and casualties to the world every year. This paper introduces the danger of mine rescue and the feasibility of disaster relief robots in disaster relief. It analyzes the development status and application of rescue robots at home and abroad, and looks forward to the development trend and direction of future mine rescue robots. With the increasing importance of the country and the large amount of capital investment, the research and development achievements of mine rescue robots will surely guarantee the personal safety of coal miners and bring considerable economic benefits.

Keywords: mine disaster rescue robot

The development of mine rescue robots At present, the world is facing disasters of all kinds every year. From earthquakes, tsunamis, mining accidents to fires, they all threaten and plunder people’s lives and property. For all kinds of natural disasters, people in all countries can only do their best to prevent and reduce the direct damage and losses caused by disasters. However, post-disaster relief work is often the key factor in determining how much damage is caused by disasters. Taking mining accidents as an example, in the implementation of the rescue process, if the survivors do not receive timely assistance within two days, the probability of death will greatly increase. China is one of the largest coal producing countries in the world. However, due to the relatively backward development of mining equipment and management level, various kinds of mine disasters occur from time to time, making the total number of mine casualties among the world’s largest. With the rapid development of the economy, the demand for coal and other mineral resources has also increased. This has increased the pressure on coal production to a certain extent, making safety production even less secure. The limitations of manpower, the dangers and uncontrollability of the environment, and the sharp increase in demand for coal mines make rescue robots a better alternative to traditional rescue work.

1 The necessity and feasibility of rescue robots

1.1 The advantages of rescue robots in mine rescue

(1) Small in size and lighter in quality. Compared to rescue dogs and rescue workers, the chance of causing secondary hazards is smaller in the collapsed scene.

(2) It can easily enter the deep danger zone of the mining area, and take detailed information to provide researchers with more comprehensive information.

(3) It is possible to do simple and repeated rescue tasks without conditions and without any fatigue.

(4) Do not worry about exposure to toxic substances and explosions.

1.2 Risk factors in disaster disaster rescue scene

In the rescue process after the mine collapse, the following are the major risk factors for the rescue site.

(1) The structure is loose. In the event of a major mine accident, the originally solid deposit was damaged due to explosions and other reasons, and structural changes occurred. Therefore, when rescue workers or rescue dogs enter the accident site, secondary collapse may occur, causing the rescue. The work becomes complicated and even hurts the rescue personnel, which intensifies the loss.

(2) Environmental uncertainty. Under normal circumstances, the workers who perform mining operations are all working under the surface. Besides the well-known oxygen-deficient environment, there are more uncontrollable factors. After the occurrence of the mine disaster, due to the uncertain environment at the work site, the danger increases. If rescue workers wear various protective clothing, they will inevitably cause inconvenience in the operation.

According to the data recorded by the U.S. Rescue Office, a survivor was rescued from a closed and confined space, and it took about 10 rescuers to spend four hours. The use of the unique advantages of rescue robots can accomplish rescue missions that are difficult or even impossible for rescue personnel to complete.

2 Development status and application of mine rescue robots

The occurrence of the "911" incident in the United States in 2001 made all countries in the world aware of the importance of rescue robots in the disaster relief process and began to put rescue robots into practical use. After more than ten years of continuous practice and application, rescue robots have made great progress, but at the same time they have exposed a series of problems in the rescue process.

2.1 Status Quo of Development of Foreign Mine Rescue Robots

Developed countries such as Europe, America, and Japan started early research on mine rescue robots. In the “911” incident, rescue robots that had been working on laboratory research began to be put into practical use. This is the first rescue activity that rescue robots have participated in. Afterwards, rescue robots attracted the attention of many large technology companies, colleges, and companies, and the amount of funds that began to invest in research has also increased.

In developed countries, the time for the development of rescue robots was relatively early, and major mine disasters were almost eliminated. However, the research and development of mine rescue robots did not stop there. In recent years, a series of research results have been achieved. The Groundhog robot developed by Carnegie Mellon University in the United States is shown in Fig. 1. The sensors that use the hydraulic system as the power, the laser technology to measure the distance, and the cameras equipped with the gyroscope and the night environment can accurately reflect the distance. The environment at the site of the mine disaster and, at the same time, establish a 3D model of the deposit for reference by rescue workers.

The serpentine robot developed by the University of Osaka in Japan is shown in Fig. 2. These robots are long and about 8 meters long, but their diameters are very small, less than a few inches. The electric motor is used as the prime mover to propel it forward. Because of its small size, it can be accessed through a relatively small slot where rescuers can't get in. Using a camera mounted on the head, the affected area is photographed for reference by researchers.

2.2 Development Status of Domestic Rescue Robots

The development of domestic mine rescue robots started late. However, as the country’s increasing emphasis has placed more and more funds on investment, it has achieved a series of fruitful results. For example, the coal mine rescue detection robot jointly developed by Kaixin Group and Shenyang Institute of Automation is shown in Fig. 3; the mining detection robot developed by Tangshan Kaicheng Electric is shown in Fig. 4.

2.3 Application and Problems of Rescue Robots at Home and Abroad

In recent years, although many achievements have been made in the study of mine rescue robots in various countries around the world, the problems that arise cannot be overlooked. For example, the West Virginia mine disaster in the United States in 2006, the Wangjialing mega disaster in Shanxi Province in China in 2010, and the Parker mine disaster in New Zealand in the same year, all of which are more or less related to robots in the rescue process.