Counter UAS with bola technology

Jamming, nets, shotgun pellets, interceptor drones: There is much discussion about ways to combat illegally operated UAS and protect sensitive areas. Researchers at the Karlsruhe Institute of Technology (KIT) are trying to prove that high-tech solutions are not always necessary for countering UAS and that seemingly outdated methods can also be effective.

The principle is simple: three ropes knotted together at one end and weighted with a stone or another weight at the other end. This is all that is needed for a bola. In the hands of skilled users, this simple construction becomes an effective weapon. In parts of South America, this throwing device is still used to catch animals. The rotating bola is aimed at the legs of runaway cattle, causing the ropes to wrap around the legs, preventing the animals from escaping.

How the bola principle works

The idea from the researchers at the Karlsruhe Institute of Technology is to transfer the principle of wrapping to counter UAS. Thin metal chains are launched toward the UAS using suitable launching devices. „We use a well-known physical principle, as shepherds in South America do with the bola, and specifically adapt it for drone defense“, explains Professor Claus Mattheck, Distinguished Senior Fellow at the KIT Institute for Applied Materials, who developed the method in collaboration with external partners. „Instead of weights on ropes, we use thin chains that have proven to be superior in simulations. Upon contact, the chains wrap around the drone’s body and rotors. This causes the rotors to lose their mobility, and the drone crashes.”

The special advantage: Reduced collateral damage

Calculations from an engineering firm examined the behavior of chains with diameters of 3 to 4 millimeters upon impact against model drones. The simulations account for friction, geometry, and movement dynamics. In the next step, the team plans to expand initial satisfactory field trials. If these are successful, the industry could take up the idea for implementation. „We have verified the basic suitability of the method through these computer simulations. A particular advantage of chains as a projectile is that they have less potential for collateral damage when falling than a compact projectile of the same mass“, explains Mattheck.