It may look like CGI in the trailer, but the droid that will join R2-D2 in the forthcoming Star Wars film - The Force Awakens - is very much real. The robot, named BB-8, took to the stage at Star Wars Celebration convention in Anaheim, California, where it literally ran rings around the retro droid on its spherical body. JJ Abrams, the film’s director, confirmed that a real robot was used during filming, but did not reveal how it works. Scroll down for video . The robot, called BB-8 (left) stars in the eagerly anticipated film Star Wars: The Force Awakens and took to the stage at Star Wars Celebration convention in Anaheim, California, where it literally ran rings around retro droid R2-D2 (pictured right) It’s a question that’s got Twitter talking, with a user named Jock tweeting: BB8? BBGREAT more like and Jimmy Wong in LA saying: ‘HOW DOES BB-8 WORK. It's so coooool.’ Joshua Harris, a teenager from Oxford said: ‘#BB8 is one of the few things in life that makes me want to understand engineering, while Video editor Ron Dot Org tweeted: ‘This is the part of the #StarWars event today that really blew my mind. #BB8 is not cgi. AT ALL’. BB-8’s body is a spherical ball that allows it to move in any direction, but it also has a completely free-moving head that doesn’t fall off, leaving applauding spectators wondering how it works. Speaking about filming the movie, JJ Abrams said: 'There were a lot of discussions about how having a CGI BB-8 could be so much easier for shooting. JJ Abrams, the film’s director, confirmed that a real robot was used during filming, instead of CGI, but did not reveal how the robot worked. Here, BB-8 the rolling droid BB-8 is spotted inside the Millennium Falcon, peeking around a corner . From today, Star Wars fans will be able to tweet using new emojis exclusive to the social network. Three emojiis have been introduced showing C3PO, a Storm trooper and a new droid. They have been rolled out in anticipation of the release of Star Wars: Episode VII The Force Awakens. To tweet a Star Wars emoji, users must include hastags: #C3PO, #STORMTROOPER or #BB8 which will be transformed into little cartoons. ‘But we talked originally about it would be better for the film, for the actors, for the sets and the look of it if it were performed.’ He confirmed that BB-8 was ‘built and puppeteered’ in the film, but no strings were visible when the beeping, chirping droid rolled on stage, leading experts to speculate that it must be controlled by at least one remote control. The robot’s body is likely to be a large robotic ball, like a big version of the Sphero, Mashable’s Andrew Tarantola speculated. The toy by Orbotix is controlled by a smartphone app using a Bluetooth connection and allows users to make it go in any direction – much like the new droid. BB-8’s body is a spherical ball that allows it to move in any direction (pictured) but it also has a completely free-moving head that doesn’t fall off, leaving applauding spectators wondering how it works . The robot’s body is likely to be a large remote-controlled robotic ball, like a big version of the Sphero (pictured). The toy by Orbotix is controlled by a smartphone app using a Bluetooth connection and allows users to make it go in any direction – much like the new droid . Professor Will Stewart, a Fellow of The Institution of Engineering and Technology in London, told MailOnline that the walking globe is easy to achieve – ‘we could build one if we had the budget’. ‘It’s related to the default egg-race-style self-propelled double wheel device or the walk-in-balloon which anyone can try,’ he said, referring to a zorb, which humans walk inside and push against the side to move along. But the real mystery is how the robot’s head can move independently but stay on top of the free-rolling ball. It’s possible that magnets are involved to ‘stick’ the droid’s head to its body, but it would require remarkable control by a human operator to make sure it’s head stayed on top of the body – and the stage performance seemed effortlessness. It could be that the droid’s head is a separate robot with its own set of remote controls, enabling it to ‘look’ around. It's currently a mystery as to how BB-8 moves, but its white and orange case may hide a larger mechanism like that found in Sphero, which allows it to move quickly in any direction. The real question is how its head stays on . BB-8’s body is a spherical ball that allows it to move in any direction, but it also has a completely free-moving head that doesn’t fall off, leaving applauding spectators wondering how it works. This image shows the robot on the set of the film, which will be released in the UK in December . It may be able to stay upright easily by depending on a gyroscope that tells it which way is up and use an accelerometer to monitor motion, much like many smartphone games. Magnets may still be used to keep the head in contact with the body. Professor Stewart said: ‘The floating ‘head’ is probably on rollers magnetically bound through the plastic ball to the "driving" robot inside.’ He explained that rare earth magnets are very strong and light and the robot’s ‘movements are consistent with this, such as a tendency to move in the direction of travel.’ ‘The inside and head could be wirelessly linked but given that this robot is radio controlled rather than autonomous…I suspect that head and body are just independently radio controlled.’ It’s possible that magnets are involved to ‘stick’ the droid’s head to its body (pictured), but it would require remarkable control by a human operator to make sure it’s head stayed on top of the body – and the stage performance seemed effortlessness . From today, Star Wars fans will be able to tweet using new emojis (pictured) exclusive to the social network . Sphero is the world's first robotic toy ball that's controlled by a smartphone app. It's been suggested that BB-8 may use similar technology in its body. The Sphero toy can be programmed to weave in between objects, follow augmented reality race tracks and even keep a pet entertained. The 2.8-inch (73mm) ball travels up to 5mph (0.6 km/h), is fully waterproof and costs $99.99 in the U.S, and £99.99 in the UK. Sphero (pictured) is the world's first robotic toy ball that's controlled by a smartphone app . The gadget weighs 178g (0.4lbs) and has a gyroscope and accelerometer inside that connect to a tablet or smartphone via Bluetooth, as well as two rubber wheels. A counterweight gets the ball rolling on demand and sensors allow users to control the direction and speed of the ball. The wheels inside work like a hamster running inside a ball and never leave Sphero's surface, so it can turn corners at high speed. There are up to 30 games available via apps including driving, sports and arcade games, and the polycarbonate ball could soon be on its way to school classrooms to give children an insight into robotics. It is hoped the waterproof ball will inspire a future generation to get involved in computer science and design and technology.
BB-8 moved in all directions on stage at Star Wars Celebration in Anaheim .
Director JJ Abrams said a real robot and not CGI was used in the film .
Audience were mesmerised by the droid but it's a mystery how it works .
Suggestions include giant robotic ball has another magnetic robot on top .