They could be practical if one could manipulate the limbs like human arms and legs. This would make them very useful for engineering work like building . If built around a human, then the limbs could have some use in combat like rescue or breaching. But on a large scale, tanks are superior in every way.

Are Mechs feasible?

In fact, having a human-piloted bipedal mech is more likely than one that thinks for itself. “This is a very feasible type of technology,” says Sethu. “More feasible than a fully autonomous system, because fully-autonomous systems have lots of problems in terms of sensing and contextual decision-making.”

What defines a mech?

A mech or mecha is a large, pilotable robot.