Vehicle propulsion & protection system patent: comments?

Discussion in 'Weapons, Equipment & Rations' started by IndependentBoffin, Jun 6, 2010.

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  1. Hello all,

    I recently filed a patent for a combined vehicle propulsion & protection system, UK Patent Application number 1000110.5. The idea is to set up a grid of electromagnets under the hull of a vehicle or structure. On the outside, a magnetically responsive pseudo-fluid (MPF) is moved around by phased activation of these electromagnets.

    Propulsion is achieved through wave-like motion of the MPF against the ground, or wetted area of a naval vehicle. Examples of MPF are hollow steel spheres, steel spheres with ceramic/foam/shear thickening/ elastomeric/explosive reactive/etc. cores. The MPF is designed to move around as a particulate aggregate under the influence of magnetic fields.

    Some benefits of this system are:
    1) Armour can be transferred co-operatively between vehicles in a formation (e.g. to lead/rear elements in accordance to perceived risk)
    2) Armour can be quickly replenished in the field, e.g. by air drop
    3) The armour can repair itself in the field (just reform any holes or replace lost MPF)
    4) Any attempts to disperse the MPF held within a magnetic field will encounter eddy current braking proportional to the rate of change, c.f. Lenz' Law.
    5) Armour coverage for a vehicle can be varied depending on anticipated threats (e.g. thicker underbelly armour when traversing a suspected minefield) or dynamically (perhaps in conjunction with an active defence system, like the Israeli Trophy)
    6) It is inherently amphibious. A land vehicle equipped with such a propulsion/protection system would be able to move through bodies of water, and vice versa.
    7) The composition of the MPF can be varied depending on threats. E.g. if more blast threats are anticipated, blast attenuating hollow and foam filled spheres can be used. If more KE threats are anticipated, ceramic-filled spheres can be used.
    8) For naval propulsion, the system is expected to have a high Froude efficiency due to moving a large volume of water slowly, rather than a small volume of water quickly (c.f. a propeller).
    9) The system will have no characteristic acoustic signature as the sound it makes (which can be mitigated using MPF coated with a damping layer) depends on the activation sequence of the electromagnets, which itself is highly variable.
    10) The system has no single point of failure (e.g. tyres, axle, gearbox) hence it is highly damage tolerant.
    11) Such a vehicle can traverse difficult terrain easily due to its variable ground contact pressure, torque and contact surface shape (it can conform and mechanically key to uneven terrain)

    My company has just received a Combined Search & Examination report from the UK Intellectual Property Office, dated 11/5/10 and examined by Mr. Rowland Hunt. Apart from some minor amendments to the claims, the closest inventions he identified in the field are US Patents 5359574, 5273465 and 6622608. The first two of these patents are in the propulsive/stealth fields and offer no protective advantages to thusly equipped vehicles. The last is for actuated, variable standoff armour which is only remotely similar to mine.

    What do you think of this patent? I'm interested in any comments, from a technical or military point of view.

    An example of a commercial application for this are conveyor belts with no moving parts.

    Development of a prototype demonstrator vehicle is somewhat beyond my personal budget but as always I am looking for ways (partners, funding, expertise) to develop this.
  2. Brilliant idea,but You would probably need a nuclear power station to power it, I doubt even a Nuke Sub or aircraft carrier would have that much spare power
  3. As ever, these things are interesting. However:

    1. How heavy is it?

    2. It reads as if you are just doing some of the job of the explosive. A cynic might say that you are attaching ready-made shrapnel (i.e. the ballbearings) to the vehicle. Is the electromagnetic force sufficient to prevent this effect?

    3. What happens under power failure? Does it all drop off?
  4. Nuclear power plant? Surely you overstate your case? :p

    An M1 Abrams tank has 0.6 mpg. That works out to about 6.3 litres fuel/mile, or about 235 megajoules/mile. I don't think that is too hard to beat. 8O

    Heat engines in all vehicles currently convert a fuel's chemical energy to heat, from which useful work is extracted as a Carnot Heat Engine via mechanical means, such as gas turbine shaft work. Any electrical power to be generated is then taken off this useful work output. There are efficiencies associated with each chemical -> heat -> work (-> electrical) conversion process; the more stages you have the less energy efficient the system.

    A vehicle equipped with such a propulsion system wouldn't need some mechanical work output to drive wheels or tracks, indeed they can be all-electric and be powered by fuel cells. Therefore they can bypass the Carnot cycle entirely.

    Furthermore such a vehicle will have no idle power consumption and can move from rest in any direction (even sideways!). Oh, and it will have a very small thermal footprint :)
  5. Depends on the amount of MPF you put on it. There would be an initial weight taken up by the electromagnets and skin, but vis-a-vis conventional vehicles, what you pay for in mass for these components you save in not having a heat engine, gearbox, drive shaft, tracks, etc.

    Furthermore, a vehicle equipped with such an armour system can start off on patrol light (with minimal MPF) and additional MPF can be air-dropped or even fired by artillery/missiles to supplement what they have in the event of meeting hostile forces. This effectively allows them to very quickly up-armour in the field.

    A valid question, but difficult to quantify convincingly using sums rather than physical tests, due to the eddy current braking effects. Every particulate component of a paramagnetic or ferromagnetic MPF will become temporary or permanent magnets respectively, akin to a pile of magnets thrown together. The faster you try to separate them, the greater the eddy currents generated that will oppose the change.

    But ultimately such a vehicle ought to have a base layer of armour in addition to the dynamic armour. And also, ultimately, any armour system can be overmatched.

    Depends on whether paramagnetic (yes, they drop off) or ferromagnetic (no, they stay on) MPF are used.
  6. How do you confine the effects of the magnetic field to the things you want to move?

    At very least you are going to have a huge magnetic signature that the enemy can use to target you.

    In all probability passing close to a magnetic object will either rip it up or pull the vehicle off course. The effect of 2 such vehicles passing each other should be interesting to watch, from a safe distance.
  7. The average fuel cell at present only produces about 0.6 or o.7 volts, so just how many cells would be needed to give enough power, and the Idea of having liquid hydrogen any where near a combat environment scares the crap out of me having seen a Hydrogen cooled bearing explode on a 600kwt steam turbine and blow a 50ft drive shaft weighing many tons into a field some miles away at Aberthaw power station in the 80s.
  8. A magnetic signature is unfortunately one of the drawbacks of this system. But as I pointed out earlier, it won't have a large thermal signature unlike vehicles powered by heat engines. So gain some, lose some :D

    Magnetic fields from a dipole decay very rapidly with distance in an inverse cubed law. Essentially the MPF or electromagnets act as dipoles, and for a single dipole the far field strength is given by:

  9. THis is all a bit "Star Trek" a bit like death rays and killer laser beams, yes they work in theory, but the cost, weight, and power required are just not viable at this moment in time
  10. Power = volts*current. Having a fuel cell with a low voltage output doesn't imply it would have a low power output. In any case a fuel cell powered vehicle won't have its fuel cells directly connected to the electromagnet array; in all likelihood it will have intervening electronics to store energy during periods of low demand or circuits to control the activation sequence of the electromagnets.

    Hydrogen isn't the only fuel available for fuel cells, e.g. Methanol Fuel Cell. Hydrogen has an amazing energy content per mass though: 143 MJ/kg compared to diesel 46.2 MJ/kg.
  11. I am not a Star Trek fan. Liberal agenda overdose! :D. And I don't think many Star Trek ideas are feasible anyway - transporters, FTL travel, etc.

    Depending on the outlook of the company/country involved, the cost may be justified in terms of this being a potentially, very disruptive technology.

    Explosive reactive armour has poor multi-hit capability, and has issues with injuring nearby dismounted infantry/civilians and sympathetic detonation of nearby tiles.

    The new electric armour concepts you might read of in the news are highly specialised equipment effective against shaped charge jets, but not larger KE penetrators, e.g. APFSDS darts. They would also be easily degraded by other types of anti-armour weapons, such as HESH.

    Cage armour only works against a very specific threat.

    All other passive armour systems have a major problem with weight against hydrodynamic impact threats. In the hydrodynamic impact regime, only two things count: the density of the armour relative to the projectile, and the thickness of the armour relative to the length of the projectile. Material strengths, elongation, etc. are all largely irrelevant due to the extreme velocities involved. Hydrodynamic velocity impact threats present themselves in the form of shaped charge jets and explosively formed penetrators. Future cannon research is also trying to put more muzzle energy into the projectile, such as electrothermal-chemical gun technology.

    With a passive armour system, if you need both density and thickness to protect against hydrodynamic impact threats, you will end up with a large block of metal. This is where a dynamic protection system would shine.

    You might think it is a high risk blue sky project, but the payoff is
    well worth it.

    The base weight of the system without MPF can be quite light as you trade off a heat engine, gearbox, axle, tracks/wheels, etc. with electromagnets, and thinner passive armour in favour of dynamically reconfigurable protection. As noted previously, additional MPF can be airdropped for in situ up-armouring.

    The power requirements vis-a-vis other land/naval propulsive technologies remains to be quantified, but there are indications that it may be more efficient.
  12. 1. I decided to develop a new, lightweight, dirt cheap and very effective explosive weapon for our soldiers.
    2. I'm preparing a research proposal for a new weapon to replace the UGL.
    3. I'm designing a laboratory test rig to replicate HRBS in a convenient setting.
    4. I recently filed a patent for a combined vehicle propulsion & protection system.

    Do you get out very often?
  13. Methanol, only slightly less dangerous than Hydrogen, the last thing you want in an AFV is more explosives, in WW2 fuel fires killed most crews, what you need is some nice inert power source, before you even think about the method of propulsion, find some nice non toxic, non flamable. fuel, and tank crews will love you, an AFV is in fact a realy handy mobile cremortotium for its crew
  14. No, how can you tell? :D
  15. I know its not on the same level, but, when i was in school i found it hard enough to do 1 project at a time and follow it through to completion.