Q&A: Bringing Chappie to Life with VFX Supervisor Chris Harvey

Creating a science-fiction robot requires a solid grounding in real technologies

A bipedal robot, covered in graffiti and wearing several gold chains.
Image: Sony
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What would existence be like for the first sentient robot? Pretty eventful, according to the action science-fiction movie Chappie, which officially opens today in the United States.

Directed by Neill Blomkamp, who previously helmed 2009’s District 9 and 2013’s Elysium, Chappie is the story of an eponymous upgraded police robot, programmed to learn and experience emotion. Post-upgrade, Chappie must then find his place in the world, while fending off forces determined to destroy him.

The key character of Chappie is computer-generated, based on a performance on-set by the actor Sharlto Copley. Creating a believable robot that could engage an audience’s sympathies, and a near-future world for it to inhabit, was largely the responsibility of Chris Harvey, Chappie’s visual effects (VFX) supervisor. Harvey talked with me about how the movie’s creators approached portraying futuristic but believable technology:

Stephen Cass: What is the role of a VFX supervisor?

Chris Harvey: I oversee all of the visual effects in the film. So that includes planning, in pre-production, how we are going to shoot things that are going to need effects integrated later. Then during the shoot we’re making  sure that we’re shooting it in the way that we need and acquiring the appropriate data. Depending on the director we can be very involved in what those video effects will be.… Once you get into post [production], you’re right next to the director: Everything from the effects creative staff is coming to you for approval and then presentation to the director.

SC: How did you work with Blomkamp—what was your brief?

CH: [I started working with Blomkamp] almost 8 months before shooting began… The brief was “we need to create this robot that everyone has to believe is real from a visual perspective [and make him so that people can] connect and relate and emote with him.” That was the big challenge of this movie—we had to take it past just believing he’s present.

SC: How do you go about building a world that’s realistic, but still visually engaging? How do you make extrapolations about how things might look in the future?

CH: Every film is different, because every film has a different visual style. … But the key is always looking to the real world and finding references.… Even if [the thing on screen] is something fantastical that no-one’s ever seen before, not having something to ground it in the familiar reality of our world will always make it much harder to accept as being real.

Now, with Chappie we took that right to the extreme. There’s literally no part of Chappie that is just completely invented. Everything about his design is purpose driven. There’s a function to every component.  There’s a ridiculous amount of real world material built into him. All of his joints and gears and all of that stuff comes from references from real robotics that exist today, so that he feel very, very tangible.

SC: What were the biggest technical challenges in making Chappie feel real and relatable, especially around actors on physical sets?

CH: All of the shooting happened in real locations, so we were on location the whole time. We shot Sharlto in all these scenes, but sometimes [he’s not exactly where he needs to be] so you have to erase him. No one likes to talk about that, but there was an army of people and all they did was just erase Sharlto out of the frame! That’s not new, but it’s certainly something that deserves acknowledgement. The animation was certainly a technical/creative achievement. We did not use motion capture like everyone thinks we did. We used Sharlto as reference, but the animators hand key-framed [the robot] on top of him.…

An interesting challenge was that [Chappie] is one character, but he evolves throughout the course of a scene. So even though you might think of him as one digital model or asset, there are 16 versions of him that we had to track from shot to shot throughout the whole film. [And, for example,] he has a battery light on his chest. And for that battery light we had to make sure it tracked the [correct] percentage from shot to shot.…

One thing we really tried to do a lot, in terms of making [Chappie] feel present in a scene, is physical interaction. We really didn’t shy away from that. If people wanted to hug him or touch him—we really encouraged the actors to interact with him as much as possible. We put these chains on him that could shake around and bump into things.... Those things are very, very hard to achieve, but the more of it that we could do, the more it sells that he’s there.

SC: Once, audience accepted robots like Robby. Now expectations are higher—are those expectations continuing to rise?

CH: Tremendously so. There’s just such an onslaught of big visual effects films. Huge amounts of eye candy. So people are becoming educated. It’s not just films—that technology is making its way into games and into everyday life. People are much more educated on it and much less accepting to the point where there’s a lot of people out there who literally go in looking for the mistakes. Which I think is a shame! 

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