Today’s invention is a monorail train which makes use of existing track.

This would have rollers, to fit either side of the rail and probably be gyro-stabilised (it worked in 1909, so the technology is proven).

This would provide for vehicles with much lower drag (being somewhere around half as wide as conventional trains, based on the wagon designs of prehistory).

The main benefit would be that it effectively doubles the amount of track available.

Since trains can be increased in length, with only a small penalty when loading at platforms of current size, this offers both a huge increase in the capacity of a rail network as well as allowing the vehicles to move more rapidly and provide passengers with a less restricted view.

Points switching would need to be timed, so that two trains could avoid a simultaneous change in direction which was not required.

NASA take astronaut comfort pretty seriously, since an annoying facial itch during a spacewalk could seriously degrade concentration and thus safety.

They have been looking for an improvement on the current technology which astronauts use to scratch their faces inside their helmets. This consists of a pad covered in velcro that they can brush their face against.

Today’s invention is an adaptation of the magnetic window cleaners used in high buildings.

It would have a ptfe coating on both inside and outside magnets (beige) so as not to scratch the visor. There would be a parked position which would allow the magnets to be clipped during eg takeoff. The prong used to contact the face could have several different heads, each with a different texture and springiness. These could be selected simply by rotating the exterior magnet.

Such a system might be adapted for regional itches elsewhere under the suit itself.

Modern tanks tend to have main gun barrels which are coated in thermal lagging.

This material is intended to protect the weapon from small differences in temperature (as might be caused by being parked under a desert sun). The resulting barrel deflection can cause serious inaccuracy when the gun is fired.

Today’s invention offers a way to attack such a tank so as to disable the thermal lagging, and render the machine largely useless, but without harming the crew.

A low velocity shell, containing a thermite core (of the type used in hand grenades or incendiaries) and a large number of eg ball bearings, would be fired at the front of the turret.

As a means of tank destruction, this would be completely futile, but the shrapnel would shred the thermal lagging and the thermite would then damage the exposed gun barrel, by intense, local heating.

Camouflaging stationary tanks and equipment is difficult, especially when you have to rely on scrim netting. This is horribly subject to snagging when dragged over the protrusions on a vehicle or a field gun.

Today’s invention is a simpler solution comprising an auxetic sheet material which changes, when stretched, from a smooth, flat sheet, to a self-supporting, 3D mesh structure.

This can be easily flattened, rolled up and stowed like a tarpaulin when the vehicle is deployed.

If you need to hide, the sheet can be dragged to a highpoint and then pulled down in several directions.

The sheet expands and covers whatever is necessary, obscuring it from view, but enabling a tank crew beneath still to make observations and target weapons.

When a rapid movement is ordered, the sheet can be released and walked inward to the high point. The continuous sheet is easy to then roll up without nearly so many snags and helped by the elastic spring-back of these materials.

The positions of aircraft carriers at sea are usually not that hard to predict, with the size of the vessels, their small number and the electronic surveillance tools available.

Today’s invention is a way for a navy to get their carriers to a new location much more rapidly than anticipated (based on estimates of the top speed of the ship). The ability to bring your aircraft to bear unpredictably on an enemy fleet provides an obvious tactical advantage.

Imagine an aircraft carrier with a docking point on its underside.

To this, a friendly nuclear submarine (which is hard to track) can attach itself, without being detected.

The dock allows the sub to add drive the surface ship, so that its speed can be greatly enhanced.

It might also allow for covert transfer of personnel or supplies.

Mechanical fasteners (mostly bolts) tend to have a threaded section protruding from their nut, beyond the usual three or four threads, when the bolt has been tightened to the correct specification.

This occurs because bolts need to be manufactured to certain standardised sizes and this includes lengths.

However, it does mean that in applications where excess weight is critical (eg aircraft, racing cars, spacecraft) a large excess mass is being carried which decreases performance.

As an example, there are ~1M fasteners on a 777 airliner.

Let’s say that half of these are external threaded types and that each of those has an excess threaded portion of 2mm of steel. This represents (for, say, M6 bolts) a waste of $11000 per year per airliner (based on the rule of thumb of $50/kg.

Today’s invention is a bolt cutter incorporated into a torque wrench, so that, when a bolt has been tightened, any excess over, say, three protruding threads can be swiftly removed.