What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

I know in general a Mech is a bad idea on many levels, cost, engineering, it's effectiveness versus other more conventional war vehicles. I also know that making a robot like a transformer that turns from a car to a robot, or something like a megazord where a bunch of Vehicles turn into one giant robot are also even more unrealistic ideas. But I don't know why in specific it is a really bad idea, the transformer and the make a bunch of vehicles turn into giant robots I mean.

Is it completely impossible for even like a realistic higher tl level beyond our own (not super-science) or is it just too much of a engineering nightmare for anyone to even seriously consider (and fund) such a thing? More or less just setting brainstorming in case I ever do get to set up a mech campaign.

Re: What areIssues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

The fundamental problem with a transforming robot is that a lack of specialization is going to have inherent costs. You see this with their real life counterparts. Whether you regard an "amphibious tank" as a tank that can go in the water or a submarine that can go on land, the result is always something that is inferior in effectiveness to real tanks and submarines. When you look at those cars that you can turn into flying machines, they are bad cars that turn into bad small planes. The transforming robot is going to have to spend internal space on machinery that does nothing for it except let it transform and it's going to have to be designed in such a way that nothing sticks out where it will get in the way of the rearrangement of components. That means it's not designed to be the best robot it can be with the available technology. It'll be expensive, delicate and ineffective.

As for combining robots, there's a similar problem. If you have five robots that fit together to make Quinbot, then you've got a problem with Quinbot's functioning in that you're going to have to power it with five separate power plants. This is a sub-optimal approach. It won't be any harder to damage than any of its components but it will be an easier target.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

It's a bit more complicated than that. It depends on what you mean by the word 'mecha'. For example, there are situations where a legged vehicle has advantages over wheels or tracks. I can easily imagine certain situations where a vehicle with a leg propulsion system and robotic arms could be genuinely useful, especially in higher-tech situations.

But it's very hard to imagine a situation where that vehicle would be shaped like a humanoid, or much like an animal. It wouldn't look like a mechanical living creature, it would look like a vehicle with legs, if you see what I mean. You could call that a mecha, but it's not what is usually meant by that word.

'Impossible' is a big word. Lots of things are technically possible, but still utterly impractical. Combining mecha (or robots) is a good example.

Let's take a fictional example: the Shogun Warrior Combatra.

Combatra in humanoid mode is a human-shaped mecha several stories tall. It is made up of five subvehicles that can merge back into a giant humanoid robotic mecha. Besides the issues of physics involved (the square-cube law applies to machines as well as living things), there are various practical considerations.

Let's say the pilot splits up Combatra to attack the enemy from all sides. They defeat the enemy, but in the process let's say Groundrover 5 gets heavily damaged, as does Skyskater Two. Fine, now the pilot wants to put the parts back together into Combatra...but the feet and upper torso are damaged, which means the head and lower torso can't connect properly, and the feet are damaged, and the reintegrated giant mecha can't even stand up. Damage to one element of the set makes the combination impossible or useless.

Same deal with combining Transformers like, say, Devastator. If something damages one of the five robots that make up the combination, it's hard for Devastator to come together at all.

To go back to Combatra...why would you want to combine the vehicles at all, other than Coolness? If the pilot can control the other vehicles/components by remote control from the head module, (IIRC in the comic AI was involved as well), there's no obvious reason to bring the swarm together at all, they're much more effective in their own specialized roles, working as a team.

It might make sense to link them together for transport...but the humanoid shape makes no sense then, it's aerodynamically lousy and forces weird design constraints on the individual components.

You might want to link them together when not in battle to reduce data load and simply controlling the whole thing...but again, the humanoid shape is pure nonsense for that.

Now, just as legs on a vehicle can make sense in certain situations, combining vehicles can be plausible for certain uses, too. But they won't be like combining mecha. For ex, I could imagine an aircraft, at a high tech level, designed to be combined with a booster stage able to get it into orbit or enable it to reenter safely, but which could be left off for ordinary use. The control system for both elements could be in the aircraft, the cockpit of the aircraft would also control the booster section.

That would be a 'combining vehicle', but not like Voltron.

Likewise, something a little like the Fantasticar, with its detachable side-pods, might be buildable and might even have some use. But note the lack of a humanoid shape.

The same general deal applies to 'transforming' vehicles. There might be some situations where a transformable vehicle could be useful. But it would be heavier than an ordinary vehicle, and the engineering necessities of building a machine able to work in multiple shapes or multiple environments would make the vehicle heavier and more expensive than one specialized for a given use.

What would such a vehicle be used for? Well, if you're mass-limited, it might be better to carry one transforming vehicle than an airplane, a car, and a submarine, assuming you could build the transforming machine. A spaceship going might carry one transforming shuttle rather three separate specialty vehicles, to save on total weight. The transforming vehicle would be heavier than any one specialized vehicle but lighter than three of them. Or if you don't know where you might need to go, the versatility might be worth the performance penalty.

But for a given tech level the specialized vehicle is likely to outperform the transforming machine in its environment. The airplane will outperform the T-machine in the air, the car on the ground, and the submarine in the water. If you want a transforming vehicle that outperforms a specialized one in a given environment, you need to assume that the T-machine is several tech levels more advanced than the specialized one.

But the transformer also has a weakness in common with the combiner. Let's say my T-machine is underwater in sub mode, and takes some minor bit of damage, that just happens to be in a component that has to move around or change shape to change over to air mode. All of a sudden my expensive and heavy air mode systems are dead weight. Plus, the extra complexity of all these systems and their tranformations adds to cost and weight and things that can go wrong.

And it still pretty much never makes sense for one of the transformation modes to be human-shaped.

So legged machines are a valid design choice for certain situations, and combining machines, and transforming machines, can make sense under certain circumstances, but have downsides. Humanoid transforming and combining mecha make no sense for any purpose other than Coolness, and like most Cool things, they make no sense when looked at coldly.

Re: What areIssues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

Some examples of combining vehicles in the real world: FICON project, Tip Tow, Tom-Tom. It didn't go well. Docking aircraft turns out to be really hard.

There's been some progress recently on modular electric vehicles, a chassis with batteries and drivetrain combined with a variety of body shells with different configurations of seats, driving positions, and so on, but in those cases neither part can be used independently.

Re: What areIssues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

There's also issues like the requirement for massive engineering redundancy in any single transforming vehicle as mechanical loads change between forms. This goes up by another exponent if you then assemble the vehicle into a load bearing part of something else.
Also, the most important part of most vehicles is the pilot - if you assemble five vehicles into one, you've got four guys sat their like drunken monkeys whilst the fifth does all the work.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

Hm interesting, The only justification for human like giant robots I found I liked is that in systems like in pacfic rim where you control the robot with your body/mind, that it easier for the human mind to grasp the idea to walk like a human rather then having to learn an entirely different method of walking. But brain controlled machinery seems to be a thing that won't be a thing before at least tl 9 to above if it even a thing that is possible.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

Well, there have been experiments with brain controlled machinery already, over the past decade.

Re: What areIssues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

In the case of Combatra from the old comic that I cited, IIRC the pilot was in the head, as is usual in humanoid mecha (though that, too, makes little logical sense in itself, the chest would be more logical), and when the mecha split up into five, the pilot flew the head-aircraft and AI systems few the other machines under the general direction of the pilot, but there was provision for living pilots if they were available.

As I noted, using that set of assumptions, I could imagine that the pilot might link the vehicles up physically when not in battle or just in transit from point A to point B, just to simplify operating the whole thing. But why does the assembly need to be humanoid?

Oh, it's almost surely possible. Difficult to implement, but there's no reason to think it can't be done, and it might even eventually be useful.

But here's another subtle point about giant mecha that is often overlooked. The 'human shape controlled by a human brain' idea is often used as a justification, but physics says no. It's the square-cube law again, that same old rule that messes the giant ants from the 50s SF movies.

Any object, when you increase its size by a factor of 'x', but keep the shape the same, increases its area by a factor of x squared, but it's volume by a factor of x cubed. If you have a cubical box 1 foot on a side, its surface area is 6 square feet and its volume is 1 cubic foot.

If we double it to 2 feet on a side, now its surface area is 24 square feet, and its volume is eight cubic feet. If we go to 3 feet on a side, now the surface area is 54 square feet and the volume is 27 cubic feet. At 4 feet on a side, the area is 96 square feet and the volume is up to 64 cubic feet.

See how the ratio changes? We go from 6-1, to 24-8, to 54-27, to 96-64.

At 5 on a side, now the ratio is 150-125, a 6 on a side it's 216-216, at 7 it's 294-343...

What that means is that mass is going to rise way faster than linear size. A humanoid shape twice as tall masses 8 times as much, so it needs a power source 8 times as large to get the same basic performance. But its ratio of surface-area to volume is only a fraction of that difference, so it has a harder time getting rid of excess heat.*

Structural strength rises as the square of the area of a supporting member, but mass rises as the cube, so a leg twice as big as a normal man's is only 4 times stronger, but supports a mass 8 times as great. A leg 3 times the size of a normal human leg is 9 times as strong (for a given material) but now has to support 27 times the weight.

What all this means is that a human-shaped mecha 30 feet high, or 50 feet high, won't move like a human, even if it's shaped like one. A human brain trying to apply human-scale motive instincts to a machine 50 feet tall will get...weird...results, at best, because it's as if he suddenly weighs 578 times as much but is only 40 times as strong. Leverage will be different, response time will be different, too.

My arm is a tad over 2 feet long. If I swing it in a round circle, my fingertip describes a circle roughly 14 feet in circumference. Let's say I take 1 second to do that, which is easily done. That means my fingertip is moving at about 14 feet per second or roughly 10 miles/hour.

Now let's say I'm piloting a 50 foot humanoid mecha and execute that same maneuver. My mecha-arm is now almost 18 feet long, it describes a circle not quite 56 feet in circumference. So in that 1-second circle, my mecha-fingertip is moving at 38 miles/hour instead of ten. So the kinetic energy is out of scale with my human form, the reaction time is off, the leverage is different because my 'body' is relatively massive compared to my strength, etc.

A human would have to relearn every motion to operate a 50 foot mecha. Nothing would come easily or naturally, even if the shape was exactly proportional.

*Remember that excess heat from the power plant? The bigger the human-shaped mecha, the worse that issue becomes, because that energy has to be radiated from the surface of the mecha, but every time the size doubles, the area increases by 4 and the volume (and heat) by 8, so the surface temperature to get rid of that heat has rise and rise and rise...

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

The short version: each form of a transforming vehicle is going to have different requirements, so it's always going to have to be burdened with equipment that is useless in its current form.

Sometimes you hear the argument that higher technology will relieve this problem. The same argument against mechs (versus tanks) applies: Nearly anything that improves the inferior design could be applied instead to the already superior one. If A>B, A+N>B+N.

Re: What areIssues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

Actually, it's not the square-cube law -- the square-cube law is only a barrier if your artificial muscles and bones have the same performance as real muscles and bones. If your artificial materials have ten times the strength of human tissues, you can achieve ten times the size (thus, after applying the square/cube law, the 10x size version is 100x stronger because of increased cross-section, 10x stronger because stronger materials, for a total of 1,000x stronger, which makes up for being 1,000x heavier).

However, the human shape controlled by a human brain model still doesn't work, because the speeds are wrong. A human at a brisk walk takes about 0.5s per step, and each step is a bit under a yard. A 60' giant would take about 1.6s per step and each step would be ten yards. Reflexes that are suited to 0.5s steps aren't really very good for 1.6s steps.

Re: What areIssues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

I mentioned the speed too, though I used arm motion as an example.

But the square-cube still applies, it's a difference of degree. Yeah, stronger materials and power sources and power trains can make up for it, to a point, but the same technologies can make non-human-shaped vehicles and machines more effective too. The conceit of humanoid mecha is that you can scale up human interaction to giant machines, which doesn't generally work.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

There's another issue with large humanoid mecha, not so much technological as tactical.

Let's say you're striding about the battlezone in your 50 foot tall or 100 foot tall humanoid mecha. Fine. Problem is, you're now a big, visible object, and big, visible objects in a battlezone tend to draw fire. An infantry man with his shoulder-mount missile-launcher can easily see you, aim at you, and fire at you. He can do so from cover, too.

Aircraft can see you, too. You kind of stand out, in effect you're a 100 foot tall guy wandering around the battlefield. You might make a nice place to get rid of a few air-to-ground missiles...

In real life, a favorite tactic of tanks is to park themselves on an uphill slope, go up just far enough to expose the main gun, and fire it from cover. You can't readily do that, granted your mecha can squat down but you're still pretty big and need a big hiding place.

There just isn't much advantage to the giant humanoid form, but there's a lot of vulnerability and vulnerable spots like joints.

Even if you're fighting another 100-foot humanoid mecha...you probably won't get into melee too often. Just as true dogfights between fighters are the exception, not the rule, so probably would be melee combat between giant mecha. Usually, one would nail the other with a missile or a beam at distance by surprise...and if you're doing that, what not use a more practical design?

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

Part of me thinks dispite all that humaoid mecha's will be a thing in the future if only as the toys of eccentric billionaires. But as you guy's pointed out, the typical humanoid mecha would basically be not very good in a war without a lot of modifications to the point it would not resemble anything close to what we think a mecha is.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

It is part of my unofficial head-canon for Transhuman Space that some of the Martian Millionaires have founded the Battletech Re-Enactment Society.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

The other thing to be said is that humanoid mecha are okay in some forms of cinematic SF. "It looks like a human so it moves like a human" is mostly okay in a form driven by visual logic.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

And I would still suggest that the transforming is an order of magnitude less practicable than a humanoid AFV...

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

A somewhat humanoid, transformable robot may be feasible and useful for some circumstances, like bomb disposal bots that can approach the IED in protected vehicle form, then unfold to do the manual work. AFVs may have one or more arms that can deploy to clear debris, open and close gates, or maintain treads.

Also some designs that already incorporate "wasted" space might be good transformer candidates, like an exoskeleton that can roll around when empty, Metroid Prime-style.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

It occurs to me that a 'collapsible' car, plane, boat, or whatever, could have its uses. That is, a vehicle that could be collapsed down into a much smaller volume for storage, then restored to its initial form. Difficult from an engineering POV but possibly handy for certain purposes.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

There are folding bicycles, of several kinds. It inevitably adds weight and cost, but the advantages are worthwhile for people who need to make part of their commute on public transport.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

And Klepper are famous for their folding kayaks. Apparently very popular with "Them".

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

In general, making something collapsible means adding structural weight and/or losing structural strength, and requires the in-use shape of the object to have an inconvenient shape or be annoyingly bulky. Humanoid mechs probably aren't awkward enough for that to be worth the effort, putting a mech in a box will have some waste space but not enormous amounts.

Making something transform usually also means that it's got inactive components that are waste mass in one of its modes -- for example, a vehicle that transforms into a humanoid will have a useless wheeled drivetrain while in mech mode and a useless walking drivetrain while in vehicle mode. Much of the time, it's more efficient to store those temporarily unused components somewhere else while not in use -- i.e. you put the mech on a truck to move it about.

Another thing to consider is detachable components. The simplest is just something that can be disassembled for transport or storage, but you could also have something like a mech that detaches its legs, attaches itself to a truckbed, puts the legs in the cargo area of the truck, and drives off (this is some savings over a straight-up truck, because the mech's power plant and controls are used to control the truck, rather than the truck having its own).

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

In a sense, the robot that's assembled out of smaller mecha is a cinematic version of this idea.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

Except the smaller mecha each include a bunch of systems that aren't useful to the combined version; most detachable component systems include a bunch of components that are unusable when detached.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

I now picture cheap fast food type transformers with limited humanoid shapes rather than sleek official Transformers/Gobots styles.
As in vehicles that simply pop out fragile manipulators and sensors without ever really looking like an android.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

I know, a long time ago, I saw a sci fi movie with a cyborg that did just that.

I really want to create some kind of world jumping scenario where such a character would make sense.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

Maxwell's mecha? (goofy smirk)

Though with the buzz word nanites, robots like the T1000 count as the ultimate version.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

We do have that, to a degree, with carrier aircraft. The Osprey is particularly impressive.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

It implies that some shared component (likely the power plant) is exceptionally expensive, so it's worth the effort to move it around instead of just having two.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

I've never bought the "With a neural interface it has to be human shaped or humans can't pilot it" argument.
Vehicular controls, and even more so, computer controls for video games, have beautifully demonstrated the human ability of extension of prioperception to inanimate object, to our clothing, our tools, and even to vehicles.
Nobody says "Today another driver's car hit my car while I was driving my car on the freeway." They say "That jackass hit me while I was on the freeway!" The other person is made synonymous with their vehicle, and you are synonymous with your vehicle. Your sense of personal space expands to be the size and shape of your car (not humanoid at all), giving you a good sense of where all the edges of your vehicle are to help with collision avoidance.

At the other end of the scale, quadriplegics who can do nothing but move their eyes and regulate their breathing to blow or suck on a straw perform the same magic trick with an electric wheelchair, with videogame characters, and these days even with drones and other remote controlled small vehicles.

People playing videogames can inject themselves so heavily into the experience that they lose peripheral vision, and have a good intuitive sense of motion and control in the world, even though all they get to do is punch buttons and wiggle a stick on a game-pad, and even though the physics in the world are inevitably inaccurate (often grossly inaccurate). Your entire lifetime of experience with how friction and gravity work can get thrown right out the window with a videogame, but people adapt very very quickly.

If anything, the "not quite right" of motion controls throws people off significantly more. Your entire body knows that you don't move forward by stomping on the ground in front of you, but it's enough like the real motion that it can really mess you up. Bad motion controls are like the Uncanny Valley of interfaces.

I can only imagine having to pilot something that is utterly unlike the human body in its actual properties by using our (definitely learned) abilities to control real human bodies is going to be like bad motion controls.

If fighter pilots and race car drivers can make do without flapping their arms or paddling their feet, I think someone with a direct neural interface can do just fine.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

Except that from what I've read, it takes a huge amount of concentration and controls to equate to even a few simple basic muscles.

For a semi-related example, it took five people to manipulate Jabba the Hutt.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

That's because it's a handwave. Absent a whole bunch of direct neural linkages (grossly cinematic), it's going to require computer control of things like balance, and once you have that it will control just fine with a joystick no matter how it's shaped.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

Because modern computer controlled planes require only a joystick to fly?

Using some form of learned/instinctive hind brain control in addition to voluntary steering isn't "that" cinematic silly.

But since the physics of giant humanoids is still radically different from that of human sized humanoids, the control issues would only be slightly lessened.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

To the point where I can get motion sick sitting on my ass in front of a video screen.

Re: What are Issues of Transforming Robots or Robots that Combine into Bigger Mechs?
 

Another issue with giant-sized humanoid vehicles (or giant humanoid robots, for that matter) is that the shape gives a high center of mass for the overall structure. This is bad in combat, everything else being equal. To put it simply, it's a lot easier to trip, unbalance, or otherwise knock over a 50 foot tall humanoid than it is a tank or similar low-built machine.

Remember the scene from The Empire Strikes Back where Luke Skywalker and the Rebels literally trip the Empire's big walking war machines with cables? That tactic might actually be a reasonable one against such machines. It would be worse for a humanoid one because a tetrapod is inherently more stable than a biped.

I mentioned upthread that legged vehicles would have their potential uses, but you'd want to avoid long legs where possible, for just that reason. Think a mechanical beetle, rather than a mechanical human.