Software stunts put on a show

The virtual stuntmen take the risks

Soon virtual stuntmen could be carrying out the physical feats too dangerous for people to take on.

Oxford-based Natural Motion has developed a simulation system that lets them swiftly generate action sequences that would ordinarily demand the skills of a stuntman.

The AI system controlling the bodies of the simulated stuntmen means they fall, run, move and react like real people.

The simulation system is already being used to create stunts for the forthcoming movie Troy.

Fatal effect

Often the death-defying stunts seen in action movies are created using motion-capture of real people or the result of painstaking frame-by-frame animation.

But Natural Motion has found a way to speed up this process and give movie makers a way of creating stunts or action sequences that would be impossible or potentially fatal for real stuntmen to perform.

The system allows the virtual people or creatures to be blown up, lose limbs, suffer falls or carry out feats that simply cannot be staged any other way.

It's not the end of the day for real stuntmen but we will take some of their jobs Colm Massey, Natural Motion

"What we do is all simulation so it's much faster and more realistic than conventional methods," said Colm Massey, head of technology at Natural Motion.

The software system Natural Motion has created, called Endorphin, is based around models of the human body that have been educated about the way that real muscles and bones work to create a convincing simulation of motion and reaction.

"We drive these virtual muscles to do intelligent things rather than just fall limply," Mr Massey told the BBC programme Go Digital.

"Sometimes you see some of our behaviour engineers lying on the ground, rolling around trying to work out how they would do something," he said, "then they try to teach the virtual actor to do what they had just been doing."

Mr Massey said: "We can say to the director 'what do you want to happen now? Do you want him to be blown up, do you want his legs to be ripped off or do you want him to fall down a cliff or reach out and grab for something and fail and stumble and fall?'"

Once the simulated stunt has been created it can be mixed in with the costumes and filmed action from a film to create a convincing effect.

Already Endorphin is being used to create stunts for the forthcoming historical epic Troy that stars Brad Pitt as Achilles and Orlando Bloom as Paris.

But Mr Massey said that Endorphin would not mean the end of real stuntmen.

"There will always be a need for live stunts, especially maybe very, very close-up stunts where you could tell it was a simulation," he said, "but a lot of the dangerous stuff where the camera was further away from the actor I think technology like ours will start to fill in all those gaps."

He said: "It's not the end of the day for real stuntmen but we will take some of their jobs."