MEMS-Based Solid Propellant Rocket Array Thruster with Electrical Feedthroughs.

TLDR

The thruster consists of a 10×10 array of 0.8‑mm solid‑propellant micro‑rockets on a 20×22‑mm substrate, each ignited by a backside‑powered heater delivered through an electrical feedthrough that traverses the propellant cylinder wall, using NAB propellant with optional RK ignition aid, and its impulse thrust was measured by a pendulum test in air. Testing showed ignition required 3–4 W with RK and 4–6 W without, yielding impulse thrusts between 2 × 10⁻⁵ Ns and 3 × 10⁻⁴ Ns after correcting for air dumping.

Abstract

The prototype of a solid propellant rocket array thruster for simple attitude control of a 10 kg class micro-spacecraft was completed and tested. The prototype has 10×10 φ0.8 mm solid propellant micro-rockets arrayed at a pitch of 1.2 mm on a 20×22 mm substrate. To realize such a dense array of micro-rockets, each ignition heater is powered from the backside of the thruster through an electrical feedthrough which passes along a propellant cylinder wall. Boron/potassium nitrate propellant (NAB) is used with/without lead rhodanide/potassium chlorate/nitrocellulose ignition aid (RK). Impulse thrust was measured by a pendulum method in air. Ignition required electric power of at least 3–4 W with RK and 4–6 W without RK. Measured impulse thrusts were from 2×10−5 Ns to 3×10−4 Ns after the calculation of compensation for air dumping.