MIT researchers have created a 3D printed nano-satellite thruster that uses ions to create thrust. The research was published in Additive Manufacturing. This leading-edge technology has only recently been applied in space exploration. Vehicles such as SpaceX’s Starlink satellite constellation, or Japan’s Hayabusa vehicle, which successfully sampled dust from an asteroid in 2005.
Ion thrusters are efficient electrical motors that accelerate spacecraft by creating a cloud of positive ions (atoms from which electrons are removed to change the atom’s electric charge), usually in inert gas. These positive ions are channeled through the motor to generate thrust, which builds over time. Though efficiency varies, the thrusters consume far less fuel than chemical thrusters, so can exist in orbit or in deep space applications for longer periods. The cumulative effect of ion thrust, moreover, allows deep space craft to achieve high velocities.
MIT’s application of this technology to nano-satellites sees a thruster printed, then immersed in a high-temperature aqueous solution and subjected to high pressure to produce zinc oxide nanowires. The printed thruster is the first of its kind to produce pure ions in its thrust, which increases the thruster’s efficiency.
Small satellites (nano-scale) can use these thrusters’ micro-newtons of force to course correct in Earth orbit.
Luis Fernando Velásquez-García, the principal researcher in the MIT laboratory that created these thrusters, points to more applications for the thrusters. The thruster’s propulsion operates electrohydrodynamically: it sprays a fine mist of ions. This spray can be used to emit fibers that coalesce into filters or electrodes that make up a kind of battery. These additional uses make the thrusters all the more valuable.
Additive manufacturing of these thrusters brings them quickly to market, although research continues on this fascinating new technology. The ability to rapidly iterate the nano-satellite thruster will, no doubt, enhance development as MIT’s team moves forward.