CubeSat propulsion technologies are taking off

CubeSats have gotten ever extra fashionable, with about 2,400 total launched to date. Nonetheless, the small dimension limits their choices for basic space exploration applied sciences, together with propulsion. They turn out to be much more crucial when mission planners design missions that require them to journey to different planets and even asteroids.

A group from Khalifa College of Science and Know-how in Abu Dhabi not too long ago launched a review in Aerospace of the completely different CubeSat propulsion applied sciences presently accessible—let’s take a look at their benefits and downsides.

The paper breaks propulsion methods into 4 classes: Chemical, Kinetic, Electrical, and “Propellant-less.” Chemical methods are the standard rockets most individuals consider when launching satellites—they burn chemical compounds collectively and expel gasoline created by the fireplace to supply thrust. Kinetic methods use issues like chilly gasoline, the place as an alternative of reacting two chemical compounds collectively, they merely push gasoline molecules out to propel themselves in the other way.

Electrical methods are just like kinetic methods however use {an electrical} system, corresponding to a Corridor Impact thruster, to warmth the propellant earlier than it’s expelled. Lastly, propulsion-less applied sciences haven’t any lively element and as an alternative, passively use the forces from space itself to maneuver about. The commonest instance of that is solar sails.

Let’s begin with chemical propulsion. That is most likely the least useful setup for CubeSats, as the fabric necessities for dealing with small explosions make the supporting infrastructure too cumbersome and heavy to suit into a standard CubeSat package deal. Although some miniaturized methods that would slot in a CubeSat framework have been developed, chemical propellant methods probably will not take off quickly.

Kinetic methods are rather more widespread for CubeSats, and the paper breaks them down into two main classes: Chilly Gasoline and Resistojet. Up to now, we have reported about methods that use every little thing from ammonia to water as kinetic propellants, which might fall below the class Chilly Gasoline. If the gasoline is heated barely earlier than launch, the system turns into a Resistojet configuration. Whereas the heating is nowhere close to the extent of explosions utilized in chemical rockets, it nonetheless will increase the pressure of the propellant exiting out the thruster’s nozzle.

Electrical propulsion is analogous in some ways to Kinetic propulsion, but it surely makes use of electric energy to warmth its propellants earlier than discharge. The paper breaks these applied sciences into three main classes: Electrothermal discharge, Electrostatic, and Electromagnetic. Electrothermal discharge methods are just like arcjets, although no system sufficiently small to suit right into a CubeSat type issue has but been developed that may present the ability wanted for such a system.

Electrospray methods use electrical forces reasonably than heating to speed up charged particles used as propellants. Charged particles are accelerated by means of a magnetic area created by the propulsion system and compelled by means of the thruster’s nozzle at excessive velocity. Electromagnetic methods function equally by utilizing an arc to ionize propellant, which is then pushed out by the magnetic field that’s fashioned across the ionized materials.

General, electrical methods have gotten extra widespread on CubeSats. Nonetheless, their materials necessities usually demand high-precision machining and different superior applied sciences that make them trickier to develop than easy kinetic methods.

Non-propellant methods have turn out to be extra widespread with the profitable check of Lightsail, the Planetary Society’s solar sail technology demonstrator. Nonetheless, different propellant-less applied sciences, corresponding to tethers or a magnetic sail that powers itself through the magnetic fields floating across the solar system.

On the similar time, many of those methods stay within the conceptual phase; their skill to supply doubtlessly limitless thrust appeals to CubeSat designers with longer-term missions in thoughts. Nonetheless, they’re once more restricted by materials growth and dimension constraints, as large structures are required for a lot of of them, and it’s difficult to pack these into the confines of a CubeSat.

With all the event happening on this planet of CubeSats, extra concepts will undoubtedly be mooted sooner or later. With launch prices coming down, extra industries and non-governmental organizations will probably be fascinated about how the platform might assist them. However irrespective of the place CubeSats find yourself getting used, they should belief their propulsion methods to get there.