Computer aids for floodlighting design

The lighting engineer is faced with many problems when specifying floodlighting schemes, not least the large amount of computation required to evaluate each potential solution in terms of illuminance grids and isolux contours across the area of interest. Traditionally these kinds of evaluations have been carried out on (programmable) calculators with a design time days for anything other than trivial schemes. Mainframe computers are used in batch mode to ease this problem, but there is a need for an interactive system directly available in the design office. Interactive desk-top microcomputers with graphics facilities make this kind of system both technically and economically viable for the small design office. This paper describes the recently implemented system at Abacus Municipal Ltd, a company involved in the design, supply, and installation of a wide range of floodlighting systems. The primary objective is to provide the lighting engineer with a simple interactive computer system for specifying the details of a floodlighting scheme, leaving the computer to perform the relatively simple but tedious calculations to determine the illumination over the area of interest. User interaction in terms familiar to the lighting engineer is considered to be important so that the engineer's skills, knowledge and experience are enhanced rather than replaced. The design time using the system is typically reduced to a matter of hours rather than days, and improved and more precise results can be presented to the potential client.