Is it possible to create a giant biological “mech”?

Is it possible to create a giant biological "mech" similar to the ones in the anime Evangelion?

Its properties are:

• Has no soul, just muscle, bone and a metalic exoskeleton to support their weight.

• Does not have autonomy, as if it were in a coma.

• Must be piloted from the inside in some way.

• Its size has to be at least 50 meters - but bigger is better.

(This is not relevant, but they are going to fight with giant aliens.)

• Probably possible yes. – Bellerophon Aug 25 '16 at 11:29
• I think it's theoretically possible (stem cells, etc), but maybe not with the today technologies. Furthermore I can't figure out why a piloted "biological" mech could be more effective than a "mechanic" one, which, I think, is simpler to create. – EngelOfChipolata Aug 25 '16 at 11:42
• No. Please see worldbuilding.stackexchange.com/questions/51771/… for the reasons why. – Renan Aug 25 '16 at 11:56
• Seconded, no. This question is essentially the same as this: worldbuilding.stackexchange.com/questions/51686/… – Green Aug 25 '16 at 12:03
• can you describe the mech in evangelion? not everyone is familiar with biblical things – Charon Aug 25 '16 at 12:28

Yes, just not humanoid

Remote control

Remote control animal is a fact. We can do it. We did it.

In 2013, researchers reported the development of a radio-telemetry system to remotely control free-roaming rats with a range of 200 m. The backpack worn by the rat includes the mainboard and an FM transmitter-receiver, which can generate biphasic microcurrent pulses. All components in the system are commercially available and are fabricated from surface mount devices to reduce the size (25 x 15 x 2 mm) and weight (10 g with battery)

No autonomy

Sadly, we pretty much did it to other humans. See Lobotomy. I sure hope your scientists will find a way to just grow brain without some parts instead of destroying parts after, but sure, such a brain can exist.

The size has to be at least 50 meters

The holotype (and now lost) vertebra of Amphicoelias fragillimus may have come from an animal 58 metres (190 ft) long;

Source: Sauropoda

So yes, this size is achievable for animal, if only barely. For why not humanoid, see:

Most of the problems is about muscle cross-section area VS weight, and metallic parts only makes that harder. And if you are going for mechanical skeleton and muscles, mechanical heart, electronic steering, what else is left to make it "biological"? It would be more mechanical mech with some bio parts... But what would be the use for bio parts in such a thing?

If alien DNA would solve muscle strength issue, and you'll use composite bones / exoskeleton (or, you know, alien ones), it may work for humanoid, why not.

• In those answers lots of problems are caused by the weight which is proportional to the cube of the size, but what about the metallic exoskeleton to support their weight ? If you allow to augment your mech what are the limits ? Exoskeleton for the excessive weight, mechanical pump to maintain a good blood pressure, ... – EngelOfChipolata Aug 25 '16 at 12:49
• @EngelOfChipolata Most of the problems is about muscle cross-section area VS weight, and metallic parts only makes that harder. And if you are going for mechanical skeleton and muscles, what else is left to make it "biological"? It would be more mechanical mech with some bio parts... But what would be the use for bio parts if you have mechanical skeleton, muscles and steering? – Mołot Aug 25 '16 at 12:55
• Just because it is humanoid, does not mean it has to be human inside. It can have multiple hearts, at multiple locations to counter the problem blood flow. It can use strands of carbon nanotube mixed with traditional bio muscle to help with weight. Can biological in the sense mean it has a self regulating system, self repairing system. – Chinu Aug 25 '16 at 13:03
• Cool answer. You got me at the soul part. hahaha. The point of the biological part is that the scientists used the DNA of the giant aliens to make the "mech" body. Basically is similar to what happens in the Anime Evangelion. – Malkev Aug 25 '16 at 13:07
• @Mołot I really don't know the percentage of "biological" and "mechanical" the question author wants. But I just quote him on the fact that some mechanical parts are allowed which is not taken into account in the referred questions/answers of this answer. – EngelOfChipolata Aug 25 '16 at 13:07