a small thought about size advantage in fictions especially sci-fi. It always happens.

Small slender robot or cyborg beats an opponent that two or even five times bigger than him. It explained in many way to make it appear legit rather than just simple plot armor.

But that got me thinking if you really have that large very customizable robot body that almost twice or triple times larger than ordinary model. Then what are the real advantages and disadvantages it have ?

Also another little question which type of cyborg body can afford more modules and weapons. Female or male one ? Of course both have same height.

  • $\begingroup$ ". . .that almost twice or triple times larger than ordinary model." How large is the ordinary model? $\endgroup$
    – Daron
    Commented Dec 15, 2021 at 17:40
  • 3
    $\begingroup$ What is the difference between "male" and "female" robot body? $\endgroup$
    – Daron
    Commented Dec 15, 2021 at 17:41
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    $\begingroup$ @Daron - "modules" $\endgroup$
    – Willk
    Commented Dec 15, 2021 at 17:56
  • $\begingroup$ I sense some deliberate mystification @Wilk, can't you explain things properly ? (lol) $\endgroup$
    – Goodies
    Commented Dec 15, 2021 at 17:57
  • $\begingroup$ @Goodies i believe Willk meant modules with male connectors and modules with female connectors. $\endgroup$ Commented Dec 15, 2021 at 20:01

3 Answers 3


Small robot is a more recent model.

eve and wall-e

Big robot has thick nickel armor, fires huge high explosive shells and has a machine gun and a sword. It has a giant 8 cylinder diesel engine. Maybe a second shield bearer robot like Goliath. It is a man robot.

Small robot has tan plastic body and energy shields, fires antimatter tipped railgun projectile, fusion electric engine. It does not have a sword; at close quarters it uses its hands. It is a woman robot.

Large body is customizable with tech from its own period. It may not be upgradable.

Small body has no user servicable parts. If it needs repairs they will buy it back and offer to sell you a new one.

Advantage of large robot: its crew really know how it works. They know every hack, workaround, tweak and kludge. They know where the dirt builds up. They know where to squirt the ether to get things cooking. Plus this crew has experience on related machines they can apply when things get tough. They can get this big beast going again pretty much no matter what. That is why it is still out there.

Disadvantage of small robot: it will seriously kick ass until it doesn't. Then it will sit down and issue cryptic statements. You can turn it off and on. Or turn it off and pinch the earlobe and pinky finger when you turn it back on, and hold them. Its user keeps a wheelbarrow handy for taking it away, because it is heavy.

  • 3
    $\begingroup$ The new robot will occasionally go offline for 8 hours of system updates. $\endgroup$
    – Daron
    Commented Dec 15, 2021 at 19:29
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    $\begingroup$ @Daron don't forget the new robot has features that require a monthly fee to work. like the "iObedience"-module that makes it not go terminator on its owner. $\endgroup$ Commented Dec 15, 2021 at 20:03
  • $\begingroup$ And don’t forget that you can’t repair it yourself since right to repair probably doesn’t exist where the robots and are. $\endgroup$
    – Topcode
    Commented Dec 15, 2021 at 21:01
  • $\begingroup$ I was inspired to write a short fiction about this androide. fictionpress.com/s/3360364/1 $\endgroup$
    – Willk
    Commented Dec 19, 2021 at 4:08

Cost and Versatility.

Having a modular robot body that can change up parts is more cost efficient than having loads of bodies with different parts.

Change up your autocannon for a grenade launcher, smokescreen, tear gas, extra armor, mobile infantry cover, radar jammer, mobile hospital, half ton of drinking water, self-destruct bomb, climbing arms, JCB arm . . . .

You only need to build or requisition the extra part rather than build a whole new robot body.

The modular robot is also easier to repair, since you can remove the broken part, fit another, and send the robot back into the field. Then you repair the broken part. Rather than having the whole robot trapped in the garage until his elbow is fixed.

Of course there is the question of why not just have a modular vehicle rather than robot body. There are loads of questions on this site about that already.


Square-Cube Law

Other answers have dealt with robot-specific points. I'll cover the boring-practical ones for scaling anything up.

Triple height, maintained proportions:

The large robot is 3x slower to turn. Strength of a large bar is proportional the the cross-sectional area, which is 9x greater. Mass is proportional to volume, 27x greater. $F = ma$ becomes $9 = 27a$, so your acceleration is one-third, which also applies to deceleration. The larger robot is also more liable to sink into the ground.

The large robot has more internal space relative to the amount of armour. You can fit a pilot inside.

The large robot can only afford to generate 1/3 as much heat per component, since its skin is only 9x as large and it has 27x as many components.

What does that mean in practice? Your large robot is ponderously slow, but can bring to bear a lot of power if it does hit anything. Large robots may also have an advantage in vacuum if hull-breaches are a problem.

Small slender robot or cyborg beats an opponent that two or even five times bigger than him. It explained in many way to make it appear legit rather than just simple plot armor.

This is generally accomplished by superior manoeuvrability. Being smaller means that the same style of motors have far less mass to push.

For "male/female" robots, there are two obvious possibilities for what you meant.

One is M/F connectors to modules, which makes no difference unless slots are unused (all space is occupied by components when in use). Having female connectors on the robot side is neater if not all slots are in use, and is more flexible for the internal layout of a module.

The other comes back to a humanoid layout, where it again makes little difference. Giant humanoid robots are horribly impractical, so whoever compromises the aesthetic more for efficiency will win. It's barely possible that a lower centre of mass might be useful on terrain which the robots will slip on or sink into, but that describes almost all terrain which is not specifically reinforced. (Skyscrapers are usually built on reinforced pillars.)

  • $\begingroup$ thanks for answers it really helps $\endgroup$ Commented Dec 16, 2021 at 6:43

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