Abstract: Field emission electric thrusters have different working modes, and can produce either droplets or ions. The thrust parameters change widely due to different charge to mass ratio of the charged particles.For different space applications, different types of field emission electric thrusters need to be designed to achieve the corresponding thrust parameters. The emission process of the thrusters and the selection and control method of the thrust parameters were discussed. The basic working principle of field emission electric thrusters and each working mode were discussed. The calculation results show that different emission modes can be achieved with different propellants, followed by the conclusion that the thrust parameters are controlled by the propellants′ species, extract voltage and propellant flow rate, etc. Design and experiment results of an ionic liquid electro spray thruster show that the thrust and specific impulse produced by the thruster can be modified by changing the applied voltage. The thrust and specific impulse can reach 16~10μN and 154~978s respectively.

Key words: field emission, CubeSat, ionic liquid, thrust, specific impulse