Motor Used to Stabilize Remote-Controlled Camera Crane
- Tuesday, 01 August 2006
It is a staple of the summer box office blockbuster: the car chase. Car chases have not only become a vital component of an action movie, they have also had to evolve, with audiences demanding even more thrills. To put the audience directly into the flow of traffic, studio executives turn to companies like Adventure Equipment, whose Ultimate Arm, a gyrostablized, camera-mounted, remote-controlled crane system attached to an SUV, gets in where the action is. Maxon Motors’ (Fall River MA) RE40 motor is used to maneuver the camera, capturing all the adrenaline-pumping moments.
Inventor Lev Yevstratov, and co-developers George Peters and Vasily Orlov, utilized the neodymium-driven motor as an integral, on-the-fly stabilizer in the Lev Head, the three-axis camera unit at the tip of the Ultimate Arm crane. The crane provides linear positioning, and the Lev Head is used for angular positioning. The 400-pound Ultimate Arm crane, mounted on a Mercedes ML-55 AMG, is itself designed to swing a full 360° in six seconds. The operators manipulate the camera and crane from inside the SUV. Using joysticks for movement, they watch several monitors in the back seat, communicating with the driver and focus-puller in the front seats via an open-mic system.
In addition to aiding the pan/tilt/rotation abilities of the camera, the 17-ounce motor compensates for a varied amount of turbulences: wind resistance from moving at high speeds (stunts are often filmed at over 100 mph), bumps on an uneven driving surface, or the swaying the Lev Head encounters when suspended from a helicopter. The result is much like a tank’s gun barrel, which remains level even if the rest of the vehicle is shaking. Past systems were fixed to their carriers and lacked compensation for turbulences; they suffered from jostling and vibrations that had to be cut out in the editing process, necessitating several takes and creating spliced-together scenes that had an artificial feel.
To ensure a steady image, the motor receives signals from an array of sensors and gyroscopes in the Lev Head and Ultimate Arm crane. Jeff Randall, sales engineer at Maxon Motors, noted that encoders, which can give feedback to help position the motor and indicate speed, may also be attached, as well as brakes. The system has been used for NASCAR pre-lap footage and also in films such as Batman Begins, where a 10-minute car chase reaching up to 105 mph was filmed in live action without special effects. Director Chris Nolan demanded realistic scenes with an integrated, continuous flow of action, rather than amalgamating a scene from multiple do-overs or relying on digital technology. Almost 80% of the scene was filmed with the Lev Head/Ultimate Arm system.
Maxon notes that the RE40 has applications outside consumer interests. The unit is found in autonomous robots for military use, medical cast-removal saws, autopilot devices, elevator motors, and production and manufacturing automation equipment.