Anyone remember the War Wheel from DC Comics World War II comic Blackhawks?
A gigantic wheel, spiked and heavily armored so that not even the largest artillery shell could penetrate it. Buildings and vehicles were crushed as it rolled along. The Blackhawks used every weapon they could think of against the War Wheel, from aerial bombs to Chop-Chop crashing his plane into it; nothing worked. Only electrocuting the pilots inside the wheel could stop it.
Over the years it was revived and revived again, losing pilots and going independent.
Well keen tech watchers noticed that a certain new product bears an uncanny resemblance to that War Wheel in miniature form.
The Guardbot. Where are the Blackhawks when you need them, eh?