EMP is an Industrial design consultancy and systems integrator specialising in motion control and automation projects. One of EMP's major market areas is film motion control, supplying complete motion base positioning and control systems for blockbusters like the latest James Bond movie, Casino Royale. In a typical filmed scene, several hydraulically actuated motion bases may be synchronised with CGI and movie cameras for carefully choreographed stunts and action sequences which involve precise positioning of heavy objects or even large structures that sink.
Positional feedback for the model platform was provided by six Variohm PT8420 cable-extension position transducers which have a high pedigree for use in harsh environments. The IP68 rated PT8420 housings were mounted in the water below the motion base with stainless steel extension cables connected to the moving part of the submerged hydraulic cylinders. This cost effective and compact solution was simple to install and set-up with no need for precision alignment. In another application to aid a simplified method of control, EMP Designs produced a 3-axis control system to provide "pick up and use" usability – where a scaled replica model of the motion base and a simple 3-button control console are used to input, record and playback complex move sequences.
The manually controlled scaled model input mechanism includes a fixed base and a moving platform with three Variohm ELP series linear position transducers placed at exact corresponding positions to the hydraulic actuators on the full sized motion base. The linear transducers provide a potentiometer output against position which is transferred through the controller to each axis to produce a move within the capability of the system. Unlike a standard joystick solution, this simple mechanism not only allows the operator to fully envisage and perform moves without specialist "gaming skills" but simplifies the control software keeping production costs to a minimum.
EMP Designs chose the ELP series slimline linear position transducers to maintain high accuracy and reliable position feedback in a compact form factor that helps to reduce the overall size of the scaled model. With spherical bearing mountings, IP65 sealing, high linearity and positional repeatability in the region of 10 2m, the durable ELP series' conductive plastic technology provides a cost effective and highly reliable product that will provide years of trouble-free operation. Dan Stanton, MD of EMP Designs says "We have integrated Variohm's rotary and linear sensors into numerous automation and motion control systems for a variety of applications over many years. With the high costs associated with equipment breakdown in the film industry, we insist upon total reliability and Variohm's product quality and support has helped us to develop high quality automation solutions, ensuring a professional application support service for our customers."
