• DRAGOȘ-ȘTEFAN NICOLESCU ICPE, Department of Electrical Apparatus, Bucharest, Romania
  • PETRU ROŞCA Military Equipment and Technologies Research Agency, Bucharest, Romania
  • ALEXANDRU RADULIAN ICPE, Department of Electrical Apparatus, Bucharest, Romania
  • ALEXANDRU MUNTEANU Military Equipment and Technologies Research Agency, Bucharest, Romania


Linear direct current actuator, Electronic controller, Cooking-off the gun, Nd-Fe-B permanent magnets, Ferromagnetic circuit, Numerical analysis


This paper presents the design, simulation, and experimental validation of a bistable direct current actuator and its electronic control system. Regarding the working principle, the bistable linear actuator is like an electromagnet with two air gaps. The difference between the newly proposed linear actuator and a classical electromagnet is the usage of two Nd-Fe-B permanent magnets to maintain the mobile core in two holding positions. Also, a specially designed electronic control system was developed. This paper aims to explain the actuator’s working principle and its novel electronic control system advantages. This equipment is used in an assault rifle to limit the self-initiation of the cartridge due to barrel heating without the operator pulling the weapon’s trigger. The proposed bistable direct current actuator ensures a short time switching between its two holding positions. The electronic controller measures the temperature of the weapon's barrel with a thermocouple and applies a voltage on the coils to switch between the two holding positions of the actuator. The actuator was developed and analyzed using the FEMM package, and the mechanical parameters were computed with MATLAB. The electronic driver was developed with PCB design software, and the working principle was validated with a circuit analysis program.


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Électrotechnique et électroénergétique | Electrical and Power Engineering