BBC News' Sue Nelson reports on the most realistic dinosaur robot yet

The Natural History Museum in London has just put on display a giant, moving model of a Tyrannosaurus Rex. The fearsome mechanical monster blinks, breathes, and roars at anyone passing by.

Sited by the main entrance, the exhibit is already proving a big hit with young visitors.

Will you look at that!

The creature is nearly four metres tall, eight metres long and weighs in at a hefty 1,300 kilograms. This makes it about three-quarters of the size of a real T-Rex, which walked the Earth 65 million years ago.

But the major advance on previous models lies in the inclusion of the latest state-of-the-art animatronic technology

"This dinosaur is a combination of 'servo-technology' with pneumatic technology," says Audrey O'Connell, NHM's head of touring exhibitions.

The model incorporates the latest theories about T-Rex

"You have feedback continuously going between the cylinders that cause the movement and the microprocessor, telling the air what to do. The result is a model that is much more precise and natural looking, and much quicker."

Dr Angela Milner, museum palaeontologist and one of the world's leading experts on dinosaurs says every effort has been made to make the model as lifelike as possible.

Sensors detect when visitors pass by

"The shape is right and the appearance is as good as our best model studies of T-Rex can predict. Its movements are just what you would imagine a T-Rex would have been like in real life."

The model also reflects some of the new thinking on T-Rex, such as the theory that it carried its tail in the air rather dragging it on the ground.

The NHM's visitor research shows that dinosaurs are still the biggest draw to the institution, with the extinct creatures being given as the primary reason for going to the museum.