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If the mech can move sideways too, it can achieve a higher velocity as moving in the length direction. All leg movements can then be coordinated for making speed only. Sideways will then be the new straight ahead. High speed is an important advantage. If there are multiple heads also, say one on each side and evenly distributed in the middle (above the legs) ...


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Climb stuff. Steep hills and mountainous terrain is anathema to tanks. They can't spread out much when attacked, ambushes are easy, destruction of the roads, bridges and tunnels can completely cut them off from reinforcements and supplies, mines are easily placed and artillery has an easy time getting a bead on them. Many mountains that form borders between ...


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Swim Wheel and tracks both suck for moving while boyant in water. Lots of arms works. Climb A tank can climb a decent incline, but a cliff not so much. If you have lots of arms, you can climb the cliff Rapel Wheels and tracks suck for descending steep drops. Dozens of arms can lock into a rope allowing to control it's own rate of descent. Right itself after ...


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Such bodies tend to not be very hospitable to life. The dark side will get extremely cold, the light side extremely hot. If there is an atmosphere this is somewhat alleviated by the heat being dispersed in the boundary zones, but this will result in extremely violent and permanent storms, not ideal either. You can (and some authors have tried, including ...


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They would probably make dragon's teeth less effective Dragon's teeth (German: Drachenzähne) are square-pyramidal fortifications of reinforced concrete first used during the Second World War to impede the movement of tanks and mechanised infantry. The idea was to slow down and channel tanks into killing zones where they could easily be disposed of by anti-...


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Damage to a tank track will wreck the track, or at least render it less functional, whereas hits on centipede legs will break or damage a few legs but leave the vehicle capable of moving. A centipede mech can climb over vertical obstacles that a tank might not be able to drive over/through. Centipede mechs can "flow" around corners, whereas a tank ...


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You can screw up wireless coms, but nothing else without destroying the power grid first The nature of the stellar event doesn't matter. In fact, the source of what's causing the power grids to black out is irrelevant. What's happening to your earth is a massive magnetic pulse, similar to a nuclear EMP. What's happening is exactly what happens with a ...


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Technological advancements have neutralized aircraft and missiles In the near future, continued advancements in sensors and directed energy weapons like lasers (e.g. THEL) and other have resulted in advanced air defense systems where anything that comes over the horizon that is visible long enough is highly vulnerable. Missiles and aircraft with engines ...


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Several ideas people gave are great. I think "Ted Wrigley" answer pick all the problems with internal combustion motors before the 1500's. But if you insist on follow the idea that is possible creating such machines far back in time I could to suggest one more option: "biodigesters": https://en.wikipedia.org/wiki/Anaerobic_digestion ...


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The Brayton Cycle (best known as the working principle of the jet engine) potentially lends itself to solid fuel because it allows continuous combustion. If you look at a jet engine you'll see (1) a big air compressor at the front, (2) a continuous fire in the combustion chamber, which adds energy to the compressed air, but crucially, no further increase in ...


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The combustion engine was developed to use gasoline simply because it was widely available as lamp oil. Later the Diesel engine was developed to use vegetable oil, but it turned out that it could burn a lot of different vegetable, mineral or animal oils. In your setting the Diesel engine itself might be too sophisticated, but if you accept a lower efficiency ...


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Diesel Engines Well before your time period people had developed a fire-starting tool called a "fire piston". It was a tube with an air-tight piston. You put kindling or some other flammable material in it, put in the piston, and rapidly pushed the piston, compressing the air. The air gets hot enough to burn your kindling, and you use that to light ...


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No need to speculate. From the wikipedia article on Whale Oil The beginning industrial societies used whale oil in oil lamps and to make soap. In the 20th century it was made into margarine. With the commercial development of the petroleum industry and vegetable oils, the use of whale oils declined considerably from its peak in the 19th century into the ...


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I'd imagine that ethanol and acetone (both easily acquired through the fermentation process) would be able to be used by just about any civilization. Along those lines, you could say that if you had electricity (totally ignoring the existence of electric motors here for argument's sake), you could separate the hydrogen from water and use that as a ...


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During WW2 fuel shortages, agricultural vehicles were run on 'wood gas' often produced on the vehicle by a crude gasifier mounted on the vehicle, so that might be something to look into, especially if fired with charcoal as a water gas reactor they are not horrible from an efficiency perspective, and are low pressure devices that can feed an IC engine. ...


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Woodgas is very useable alternative that is relatively easy to make and can run in an internal combustion engine with very few modifications. Here is a link to a video that shows a guy converting a small bike to run on it, complete with an onboard combustion chamber made from a bee hive smoker. This channel has a decent series of videos that explain how to ...


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Wood An interesting example of fuel for cars is wood - during periods of fuel scarcity, for example during WW2, many ICE vehicles were modified to run on wood gas by adding a relatively simple gasifier device, which allowed the modified cars and tractors to run on firewood. It's much less convenient than gas, but it's possible, as illustrated by more than ...


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Check out the Pyréolophore, which ran on "controlled dust explosions" of various experimental fuels. The fuels included mixtures of Lycopodium powder (the spores of Lycopodium, or clubmoss), finely crushed coal dust, and resin. The Pyréolophore was invented by Joseph Nicéphore Niépce and his brother Claude, and a patent was granted in 1807. ...


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Believe it or not, the industrial revolution wasn't built on gasoline and the internal combustion engine. The industrial revolution was built on steam generators — aka external combustion engines — which used (primarily) coal to heat water and create steam pressure to drives pistons. Steam power requires: A sufficiently concentrated heat source: coal, lots ...


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There are internal combustion engines that use gaseous fuels: https://en.wikipedia.org/wiki/Gas_engine . A common real-world example of this type of ICE can be found in commercially available tri-fuel generators that run on gasoline, propane, and natural gas. Options for fuel that should be available given the tech era of the 14th/15th century include ...


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Alcohol works perfectly well - indeed, it's arguably better because it allows higher compression without the need for a bunch of octane-boosting additives. Model T Fords and other early cars will run on it, if you take care to replace a few parts like gaskets and carb floats that might be adversely affected. Likewise various forms of biodiesel, including ...


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As other answers stated suction would not be very effective. But only if you want to use it into thin air. In dense water it is quite different, suction is used by a lot of fishes to catch their prey, a mouth that extends and widens to pull in the surrounding water with whatever is in there is quite common. Your weapon could be a trap set underwater near ...


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Make a hurricane While all other answers were correct in a sense that a vacuum device have to rely on surrounding atmosphere to do any actual damage, they did not took into account factor of inertia. Make air move fast enough and it'll create large force (dynamic pressure). An atmospheric pressure difference of merely ~10% over a country-sized region is a ...


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Suction weapons exist in nature, octopuses and squids use them (suckers). Problems You seem to be interested in something that acts at range, and in air. These seem like problems. Firstly, as others have said, the air pressure (1 atmosphere on Earth) sets the upper limit to how hard you can ever suck with air. In this extreme case you extort zero pressure (...


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One of the most common misconceptions about vacuums is that they create some sort of sucking force. This is exactly wrong. A vacuum is simply a low pressure area. The force that acts on the air, water or what have you into the low pressure area comes entirely from the pressure of the air/water/whatever around it, not from the vacuum itself. Since all of the ...


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The Jet engine Suction Tank If you aren't worried about being practical, you could create a suction weapon by putting a high bypass jet engine on top of a tank. This would have a suction range of around 10-20 feet, which would be smaller than the length of the tank itself. The exhaust would be dangerous up to around a hundred feet- a more effective weapon ...


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Suction Weapons as described are not all that effective The only reason a pool drain can kill like that is because you have the weight of all that water behind them. In general, a 1 atmosphere of pressure difference is not enough to kill a person and the actual pressure gradient caused by a suction means you have a pretty short range on what ever weapon you ...


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The BugZooka is such a weapon! source BugZooka is a fast, simple, and clean way to rid bugs from your home The innovative and light weight new BugZooka lets you keep your distance and avoid bug squish and splatter It's unique patent pending design creates 10X the instant suction of heavy battery powered devices Bugs are sucked instantly into a removable ...


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It would be very complicated, and break down a lot, and take a lot of muscular strength. You'd need to regular crank the legs with your arms, build up some degree of movement in springs and elastic bands, and charge up a complex mess of gears. You couldn't maintain it with swaying arms and such, you'd need to have some sort of internal thing to store energy. ...


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