Control Hardware Design of a Robotic Follow Spot System

Abstract

A follow spot, known as a spot light, is a kind of stage lighting instrument which projects a beam light onto a specific, mobile, and individual object, i.e. actor. The developed system pans and tilts the follow spot by using its actuator mechanism, manual operating mechanism, tracking sensors, and control system. The system operates in four modes (manual operation, pre-defined motion saving/playing, auto tracking, and console operation). In the manual operation mode, a human operates the robotic follow spot by using a force sensor (load cell). This mode is activated in emergency situations and for pre-defined motion generation. The pre-defined motion saving/playing mode is applied for motion playing, which is generated by a human. A specific trajectory, e.g. circle, rectangle, and etc., can be saved and played for future use. The auto tracking mode makes the beam light to follow the actor. A vision system is used to detect the actor’s location. In the console operation mode, the robotic follow system communicates (through DMX512 protocol) with the light console, which controls the various lighting instruments in the theater. This paper explains the system design that fulfills the above stated 4 modes in detail. In addition, experimental results are presented in snap shot photos.