Laser-Driven Mini-Thrusters

Laser‐driven mini‐thrusters were studied using Delrin® and PVC (Delrin® is a registered trademark of DuPont) as propellants. TEA CO2 laser (λ = 10.6 μm) was used as a driving laser. Coupling coefficients were deduced from two independent techniques: force‐time curves measured with a piezoelectric sensor and ballistic pendulum. Time‐resolved ICCD images of the expanding plasma and combustion products were analyzed in order to determine the main process that generates the thrust. The measurements were also performed in a nitrogen atmosphere in order to test the combustion effects on thrust. A pinhole transmission experiment was performed for the study of the cut‐off time when the ablation/air breakdown plasma becomes opaque to the incoming laser pulse.