Large-caliber (21mm) coilgun
Fire-and-rescue equipment
Designed as rescue line thrower and remote window breaker
Specs. and Features
Introduction
KC576 is a 21-mm caliber, multi-stage reluctance coilgun. It is a rescue and engineering device primarily used for water rescue, breaking windows during fires, power-line installation, and similar situations.
KC576 can accelerate a standard projectile (Φ20 mm, weighing ≈80 g) to a maximum speed of 54 m/s and launch it to a distance of approximately 130 m. When a standard rope (diameter 2 mm, mass 1.6 g/m) is attached to the projectile, the range is about 55 m on level ground.
Its working principle is similar to that of a switched reluctance motor; put simply, electromagnets attract ferromagnetic projectiles. Unlike conventional launching devices, this principle does not require gunpowder or high-pressure gas. Therefore, the launcher is safer and better complies with laws and regulations. During each launch, there is little noise and no fire, smoke, or residue.
KC576 comprises accelerator modules, power modules, and a controller module (user interface). Its system is mostly the same as that of the KC572, except that it has no projectile feeder. The accelerator module consists of 12 coil stages, powered by a capacitor bank and IGBT switches. The core of the controller is an MCU. The software supports advanced functions, for example predicting range based on barrel elevation.
Indoor testing
Without the rope (only projectile itself), measured throwing range is ~130.
With rope diameter of 2mm and weight of 1.6g/m, measured throwing range is ~55m.
A script is built to simulate the throwing range with rope. The simulation model considered the air drag, inertia, and stress of the rope and projectile. The simulation aligns well with the field testing result. This algorithm is migrated to the microtroller on board the KC576 for precise prediction of the distance.