Posted to News on 18th Feb 2008, 20:36
Linear sensors provide high reliability for movie motions
Variohm-Eurosensor has supplied a number of different sensor products to EMP Designs for high-reliability motion control systems destined for the film industry.
EMP Designs (www.empdesigns.co.uk) is a leading 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 films such as the latest James Bond movie, Casino Royale.
Within the film industry, schedules are highly complex and delays are very costly. EMP therefore places a strong emphasis on equipment reliability - which is something that Variohm-Eurosensor can deliver with its linear position and cable-extension transducers.
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 involving precise positioning of heavy objects or even large structures that sink.
Positional feedback on a model platform in Casino Royale was provided by six Variohm PT8420 cable-extension position transducers that are highly suitable 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 arrangement was simple to install and set-up with no need for precision alignment.
Three-axis control
In another application to aid a simplified method of control, EMP Designs produced a three-axis control system to provide 'instant' usability - where a scaled replica model of the motion base and a simple three-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 positions that correspond exactly with 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, this simple mechanism not only allows the operator to fully envisage and perform moves without specialist 'gaming skills' but simplifies the control software and keeps 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 10um, 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 dependable product quality and attention-to-detail support has helped us to develop high-quality automation solutions, ensuring a professional application support service for our customers."
