Here starts your source of truth on new patent publications you need to know about in the space industry. We’ll be writing quarterly and will be getting a bit technical, to keep things lively.
Some say that patenting in the space sector is rarer compared to other sectors and they’d be correct – but this is changing. Whilst commercial discretion and institutional confidentiality are often priorities for those in the space industry, the number of space related patents are now accelerating… astronomically.
Before we move forwards though, here’s a quick systems check on some of the key granted patents in the space industry over the last few years.
For the best recent patent in aerodynamics, the award goes to…
Ah! But let us first say a word or two about problems in this field. For a spacecraft to return to Earth safely, it must re-enter Earth’s atmosphere. During that process, the spacecraft must be able to withstand the high aerothermal flux that results from reentry, i.e., slowing down the spacecraft from a velocity of around 8km/s (29,000km/h) as the density of the atmosphere increases.
For this reason, spacecraft that are intended to return to Earth must have a heat shield to dissipate, roughly the 1,000 to 1,500 Degrees Celsius generated during reentry. Single use heat shields have been used in the past, however reusable heat shields are more popular to reduce costs. The space shuttle for example, used High-Temperature Reusable Surface Insulation tiles. The problem with these tiles is that they comprise many different sizes and shapes which need to be periodically replaced. SpaceX seems to have solved this problem by developing more uniformly sized tiles, reducing costs even further.
What caught our eye in this area is the use of flexible / inflatable heat shields. They weigh much less than the carbon / silica tiles mentioned above, and they can be stowed away when not in use. Is this technology better suited for interplanetary exploration? We think it is, due to its deployable nature. So our very first award for best recent patent in aerodynamics goes to:
NASA – US10934028B2 – In-Situ Passivation and Insulation Layer for a Flexible Thermal Protection System (FTPS)
Figure 2 extracted from the 10,934,028 patent shows a spacecraft 10 including a primary structure 12 and a deployable flexible thermal protection system (FTPS) 14.The patent claims protection for a method of providing a thermal barrier.
To summarise a (rather) lengthy first claim, the method involves positioning a layer of material comprising boron nitride nanotubes (BNNT) adjacent the surface to be shielded from thermal energy. The elemental particles react with the BNNT when the outer exposed surface of the layer of material is exposed to a high temperature gas or a thermal load greater than about 300 degrees C. The material forms a refractory material in a passivation and insulation sublayer comprising boron oxide, boron carbide, or boron oxide and boron carbide. A gas barrier and the refractory material provides in situ heat passivation that minimises transmission of heat and/or radiation into the surface to be shielded.
For the best recent patent in propulsion, the award goes to…
But wait! What type of propulsion are we talking about? Well, anything that can be used in space of course. Propulsion systems are used to launch payloads into space and allow spacecraft to travel to other planets. Propulsion systems vary widely in their design and in the propellant they use.
Our first award for best recent patent in propulsion goes to:
LOCKHEED MARTIN CORP
Lockheed Martin Corp – US10495028B1 – Thermoelectric rocket propellant tank pressurization system
Figure 1 of the 10,495,028 patent shows a propellant tank pressurisation system.
The patent claims protection for a rocket engine system comprising
- a combustion chamber,
- a propellant tank to hold liquid propellant,
- a pump to pump the liquid propellant from the tank through a thermoelectric generator (TEG) system and a heat exchanger;
- the TEG system configured to produce electrical power for the pump based at least on a temperature differential between the liquid propellant from the at least one propellant tank and heat produced in the combustion chamber during an active state of the rocket engine;
- the heat exchanger configured to receive heat from the combustion chamber and pressurize the at least one propellant tank by heating at least partially liquid propellant received from the TEG system; and
- a control system configured to alter a thermal coupling of the TEG system to the heat produced by the combustion chamber based at least on a temperature monitored for a hot side of the TEG system.
This patent describes an autogenous system which employs both electrical power to drive a pump mechanism and cryogenic propellent that is gasified and heated. Instead of using additional inert gasses which require dedicated tanks, equipment, pumps, and complexity, the examples described in this patent employ thermoelectric generators to power pump systems to autogenously pressurize ullage space in propellant tanks.
For the best recent patent in structures, the award goes to…
Before we get to that, we need to talk about spacecraft structures. Spacecraft structures are important, because when they are properly engineered, they ensure that the weight of the spacecraft is minimised without compromising strength. High speed vehicles such as rockets, particularly reusable rockets, tend to have high maintenance costs and well engineered structures help to reduce those maintenance costs.
BLUE ORIGIN LLC
Blue Origin LLC – US10518911B2 – Control surfaces for use with high speed vehicles, and associated systems and methods
Figure 1A shows a rocket for transporting humans or cargo into space.
The patent claims protection for bidirectional control surfaces attached to the rocket. The control surfaces are able to alter the direction of travel of the rocket when the rocket is flying in a first orientation or a second orientation. The first and second orientation might be in an upward direction or a downward direction, respectively.
Bonus Award! Space Junk
Increased activity in space, particularly the recent trend toward smaller satellite missions such as CubeSats, has led to a proliferation of space objects. Orbital debris is a growing problem in low-Earth orbits. Consequently, there have been numerous innovations in this area to try and mitigate this problem.
Best practice is to deorbit the satellite before it can no longer be controlled and be at risk of colliding with other orbital objects, which may result in thousands of small pieces of debris, thus causing even more space junk. So, the bonus award goes to:
UNIVERSITY OF FLORIDA RESEARCH FOUNDATION INC NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NASA
University of Florida Research Foundation Inc National Aeronautics and Space Administration NASA – US11267589B2 – Drag-based propellant-less small satellite attitude orbit and de-orbit control system
Figure 7 below extracted from the 11,267,589 patent shows an attitude, orbit, and de-orbit control system (AODCS) for use on small satellites, such as CubeSats, or larger vehicles up to around 100 kilograms.
The patent claims protection for a AODCS for a satellite. The system has one or more selectively retractable booms to provide drag during de-orbiting of a satellite over a predefined de-orbiting time; and a controller to generate instructions for causing retracting or extending of the one or more booms.