Bomb Detection and Disposal Robots
Research and documentation by Praneet Dighe and team- ISA, Manipal student section.
General overview:
Robots are used in places where it out-performs humans and at times where the risk of losing lives is considerable. Bomb detection and disposal requires a high risk of accident and skill for its operation to succeed. Thus, we have been using robots for the past few decades to scout areas for military operations safely, test new explosives, dispose off broken/old explosives. These are not technically Robots but are some machines put together to form a system to do some specific tasks. These tasks include movement of the machine, detecting a bomb, safe disposal of bomb and retreating. Various engineering fields are required to facilitate the above-termed operations, mainly wireless communication technology and micro-controller system connected with a motor arm and the robot’s body for movement.
Here is an advanced robot used by the military for terrestrial area scouting purposes.
The Need for a Bomb Disposal Robot:
The development of synthetic chemicals has increased the production of powerful explosives. Most of the time, the material with a doubtful origin is manipulated by specially trained bomb squads. However, complicated and even remotely controlled triggering mechanisms challenge a specialist’s talents since the explosive is prepared for tremendous damage. Today’s squads wear safety suits in case of an explosion, which minimizes an explosion’s pressure and prevents injury to a certain level. On the other hand, they limit movement capabilities and increase stress. Despite advanced safety precautions, handling of explosive ordnances brings high risks for the operator’s life. The primary reason and justification of the need for a bomb disposal robot is simply the fact that it saves human life in an explosion. The robot can be operated meters away from the danger zone, providing a totally safe place for explosive specialists. In addition, these robots can be used not only to disarm the explosive ordnance but also to collect information about the threatening material and the area before human interference.
Application Areas:
• Handling and manipulation of explosives,
• Handling of biological, biochemical and other hazardous materials,
• Manipulation of suspected packages,
• Neutralizing and disarming unexploded ordnances,
• Determining and disabling landmines,
• And collecting visual information in an unsafe environment.
Movement of the robot:
Moving machines are not new in today’s world but for starters, it’s basically a machine that includes x motorized wheels, which are remotely controlled and made in a way that supports other sub-systems of machines on it. Various sensors like a Camera and eco-location systems are placed to help better control and navigate around the area. Micro-controller remote is used to control the acceleration and direction, it sends and receives signals through air by infrared signals, Radio frequency and other signals can be used but due to congested environment during operation IR is preferred here.
From the above basic hardware, it can carry some load and navigate around and hence next step of operation is able to proceed.
Above is an Arduino microcontroller which helps us to control the motors and various other sub-systems of robot.
This is a 12v brushless dc motor which is efficient and quiet and it is able to produce torque in range of 500–5000 mNm.
Bomb Detection and Disposal:
A simple but highly effective system of metal detectors is used to detect suspected area, sometimes various specific sensors like x-ray, infrared sensors are used as a facilitatory system for achieving higher accuracy of detection.
A miniature metal detection stick is also used in conjunction with other sensors.
After detection disposal process begins, the oldest method is to spray water using a mounted pressurized water jet over bomb circuit to short it and render it ineffective. It requires a basic pressurized pumping-nozzle spraying system but it increases weight and reduces range of robot.
We can then retrieve the explosive by physically going to the place or use a mechanical robotic arm that could be mounted on the machine.
Sub-system technologies:
Most of robots are used in wireless and out of view conditions which require various level of wireless and electronic technological hardware and tuning. Basic hardware for enabling wireless function include EMR radiating and catching antennas and its controllers that can be tuned to a remote. This can also add a GPS functionality which makes it much easier to navigate remotely.
This antenna is able to cover about 2 km range with using about 50–75 mW of power and operates at about 400 mHz. This is highly efficient and effective for its range and power consumption.
Since the operation is wireless, direct power cannot be supplied and hence a High-capacity battery pack to power all sub-systems throughout the operation. It should be chosen with balance of capacity and weight depending on range and time of duration of the operation.
Batteries of various capacities are used depending on duration of operation, generally a battery with 12v output is necessarily required as minimum since the motors are 12v dc at minimum.
Areas can be wildly challenging to travel; navigating is essential part of time-sensitive operations. An Electric motor system and transmission system is placed for handling and a static or moving camera is also used for feedback to the operators.
A continuous track system is also generally used for uneven surfaced areas.
Conclusion:
The system working coherently with operator while having versatile movement, sensory data and disposal mechanism make it perfectly fit for bomb detection and disposal. In addition, various sensor system for each sub-system can be chosen according to budget and duration of operation makes it much economical and reliable. These are without a doubt a good replacement for human scouts and hence we have seen rise in implementation of this technology by various militaries around the globe.
