CANopen in stage door system

Source: CAN Newsletter September 2006

The “Golden Camera Award” takes place every year in the German capital of Berlin. The main point of this spectacular event is to award prizes to important persons of television, radio and cinema. The live event in February is broadcast by the German television Zweites Deutsches Fernsehen (ZDF).
Last February, the host of the show Thomas Gottschalk awarded prizes to Charlize Theron, Hugo Egon-Balder, Jörg Pilawa, Carmen Nebel, Xavier Naido, Bob Geldof, Pussycat Dolls, Thomas Hermanns und Rudi Carell. In 2007 the stage will be used for the third and last time.
The stage built by Berliner Union-Film dimensions 20-m width × 20-m depth and 8-m height. The Berlin-based company Ancos controlled the seven auto-moving elements on the stage. Four of these elements are two pairs of semicircular gates. One pair of gates in front of the seats each has a length of 4 m, a height of 2,5 m, the weight is 2 000 N. The other pair of gates in the back of the stage each measures 4 m × 4 m and carries 32 television devices with a weight of 5 000 N. The remaining three auto-moving elements are flat panels, each of which measures of 2,5 m × 3 m. They carry 24 televisions linked to a large-scale screen with a weight of 3 000 N.
The two semicircular gates in front of the seats move on a circular path in a 10-m diameter. The moving velocity is 0,2 m/s. They can be closed in front of the seats in the middle of the stage. They open simultaneously to the right and left side of the circle to one of eight programmable positions. Maximum way is closing the gates at the back of the stage. One of the requirements was that the gates reach their position with an accuracy of 1 mm without overshooting. The reason was that the visitors may have been disturbed if the gates remained a little bit open in the front position or if they closed with a noise.
The weight of each gate is carried by eight rolls to the stage floor. Each gate is moved by a semi-circular sword connecting the gate with the driving system under the stage through a slit of 20 mm in the stage floor. Each driving system consists of an AC motor with a gear moving at a circular rack. The cable for power and control are carried in a circular chain. The two gates in the back of the stage each carry 40 video monitors and move on a circle of diameter 10 m.