Automation of a real-time stage followspot

Abstract

Followspots play a fundamental role in live theatre performances. These are used to selectively illuminate a particular area on stage, hence drawing the audience attention. Conventional followspots require a manual operator to manoeuvre the beam direction. Such operators need to be skilled and must also have stage knowledge. A steady hand is also required since the slightest errors will be shown (and amplified) on the illumination point. This dissertation deals with a feasible system that automates this manual process, thus ensuring a real-time light tracking system. A robotic lighting fixture, known colloquially in industry as a “moving head” is used to replace the traditional followspot. In this project, the fixture is continuously updated with real-time pan and tilt values to track the position of the actor. In order to find the location of the performer, a reliable positioning system was required. In fact, after analysing several technologies an RF based sensing platform was chosen. To localise the actor, the method of trilateration was applied. The proposed system was developed and tested for accuracy, precision and response characteristics. Finally, the project was tested in a theatre scenario where the system was setup to successfully track and illuminate an actor on stage.