Meeting BB-8
We have all waiting too long for the new movie of the Star Wars saga: The Force Awakens. And now it’s here and it is breaking all records. In the first twelve days of its release, the movie already hit $1bn at the box office. This hasn't been seen since the release of Jurassic World.
J.J. Abrams begins the new trilogy introducing new characters but preserving the taste of the Star Wars Universe. Robots are a main component in the saga. Just to cite some of them, we have the droid army of Star Wars: The Phantom Menace, or the famous C3PO or R2D2 in all the first six movies. R2D2 in fact acts as one of the central characters in many movies, saving the main ones more than a couple of times.
One of the most difficult challenges in the new movie was to create a new robot as lovely as C3PO or R2D2, but completely new. BB-8 was a deal for the Force Awakens team. J.J. Abrams discovered some drafts from Ralph Mcquarrie made in the 70’s and took them for his movie. BB-8 is completely new but always has been a part of the Star Wars cast.
How BB-8 works
BB-8 is a spherical robot that moves by rolling. One of its main component to control stability is a gyroscope, which is one of the most used sensors in robotics (and other devices like ships, aircrafts or the Hubble telescope). A gyroscope measures angular velocity, or in plain words, the turning speed. The gyroscope is usually mixed with an accelerometer, which is a sensor that measures the acceleration in the three axes. Together they provide the robot with the necessary measurements to maintain stability.
Another special feature of our little friend is his head. It is always at the top of the body. As it is explained in Techcrunch, the head uses a series of magnets that avoids it to roll off. As it can be seen in Fig. 2, the magnet of the head and one of the top of the body attract themselves, while the ones located to the sides repel each other. This mechanism allows the head to be always on top.
A very interesting detail is how the spherical body moves. Inside the body there is a wheeled mechanism. When these wheels are moved through remote control, there is a change in the center of mass position. This variation produces a loss of stability that generates the movement.
The action is similar as when a person is leaning forward. If the person leans forward too much, he will lose stability and he will need to take a step forward if he doesn’t want to crash his face with the floor.
The math is very straightforward. If the projection of the center of mass in the floor is inside the shade of the feet (what is called the stability region), the person is stable. If the projection is outside the stability region, then you go down like a brick. It is the same with BB-8. The difference is that in the robot case the stability region is a point, the contact point between the sphere and the floor. That way the movement is easier.
BB-8 is a real robot. In fact, there are already two toys available, a smaller version from Hasbro, and bigger version from Sphero. You can have it in your house and the most exciting thing is that not only humans enjoy them, cats also love these robots and they would try to play with them as John Boyega says: “My cat is always trying to catch BB-8 in my house, I like to wind him up with this toy”.
The use of robots in Star Wars movies
During the past few years, Hollywood changed the way they produced visual effects (VFX). Puppets and robots were substituted by chroma and computer designs. When J.J. Abrams faced the Star Wars VFX, he was convinced to go back and use the puppets again. Even though there are still digital characters, like Snoke or Maz.
You will appreciate this is in Jaku, that planet has a lot of creatures. It really feels that all of them are completely real. The starships are also similar to the ones in the old movies because they were created the same way. Digital creations are just visual support but not the center of visual effects as happens in films nowadays.
“In the first Star Wars movies you felt that you could touch every character, I wanted the same in the Force Awakens” J.J. Abrams.
Another good example was the scene when Finn turns on the Dejarik holochess board by accident, this game was shown in "A New Hope" and returns again in this movie created with a technique called stop motion. This is more difficult because you can create that game using computers, faster and with better results, but with less reality. J.J. decided to give us the same view as in “A New Hope” creating the holochess with the same method, using toys and picture by picture.
Furthermore, BB-8 is the definitive example that shows that this movie is made to give us a trip to the past. “It was very important to make BB-8 as real as possible” J.J. Abrams, and he succeeded. BB-8 is completely real. We saw him in the London premiere, rolling through the red carpet as a part of the cast. In the filming, BB-8 was there with the actors, running with them, being a part of the scenes and making the playing easier for the actors. They didn’t need to imagine him. Check out this video to meet how he got on with their colleagues.
You can find this article in Spanish at www.laseptimacaja.com