LabVIEW-based fuzzy controller design of a lighting control system

Abstract

This paper describes how we design a lighting control system including hardware and software. Hardware includes light sensing circuit, control circuit, and 8255 expanding I/O circuit, PC, and bulb. Sensing circuit uses photo-resistance component to sense the environmental light and then transmit the signal of the lightness to the computer through an 8-bit A/D converter 0804. The control circuit applies reed relay in digital control way to adjust the variable resistor value of the traditional dimmer. Software incorporates LABVIEW graphical programming language and MATLAB Fuzzy Logic Toolbox to design the light fuzzy controller. The rule-base of the fuzzy logic controller either for the single input single output (SISO) system or the double inputs single output (DISO) system is developed and compared based on the operation of the bulb and the light sensor. The control system can dim the bulb automatically according to the environmental light. It can be applied to many fields such as control of streetlights and lighting control of car's headlights and it is possible to save energy by dimming the bulb. Experimental results show that the fuzzy controller with the DISO system can make bulb response faster than with the SISO system under sudden change of environmental light.