BY ADAM GRACE
As the design work progressed, the realities of filming the APU scenes were discussed. Owen Paterson and Supervising Art Director Hugh Bateup outlined the requirements of a fully detailed APU prop for live action filming. The initial brief was that the APU should be capable of initiating movement, with the SFX Department providing the motive power.The APU would also need to be able to support the weight of actors climbing over the body and riding in the carriage. It would also need to withstand the stresses of being laid on its sides, back and front, and have major joints easily disconnected for transport and VFX requirements. It would serve as an on-set prop enabling interaction for actors and allowing many shots to be completed in camera. It would also aid visual effects in how the CG APU should look and move in each set-up.
Ultimately one full size, fully detailed articulated APU was constructed. It stood over 4 meters tall and weighed 3 tonnes. It could be disassembled for transport and for achieving certain visual effects shots; for example, when the guns are firing the arms were removed so CG arms and guns could be added to the live action footage. A shaking mechanism added interactive arm and shoulder gun recoil movement. A second “carriage” was built to fit a SFX supplied motion base for shots involving close ups of the actors operating the APU. The motion base was programmed to match animation of CG APUs. A second, but lighter urethane foam APU was built for scenes showing a downed and heavily damaged APU on set.
The APU was built in the prop manufacture department under the supervision of Props Manufacture Supervisor Peter Wyborn by APU Foreman Adam Grace and APU Engineering Foreman Martin Crowther. On-set articulation was supervised by SFX Design Engineer Dave Young. Motion-base engineering was supervised by SFX Design Engineer David Pride.