Performance Analysis of Fuzzy Logic Controller Applied on Portable Roaster

Roaster is a device commonly used to roast various products, especially for food processing. In the roasting process, temperature parameter plays a major role in determining the final quality of the roasted product. In real-world applications, some products must be roasted at low temperatures such as cocoa products and others must be roasted at high temperatures such as coffee products. In addition, roasting is sometimes not always carried out at a constant temperature, but sometimes it must be done at various roasting temperature levels for the purpose of forming the optimal flavour. Thus, a roaster must be able to operate at the desired operating temperature, not only a constant operating temperature but also able to work with varying operating temperatures. For this purpose, a roaster must be equipped with a reliable temperature controller. Several control models have been developed by many researchers, including fuzzy logic control. This research was conducted to design, implement, and evaluate the performance of a control system based on fuzzy logic on a laboratory scale portable roaster. For this study, a fuzzy control system with two input variables, namely the difference in temperature and changes in temperature difference as well as one control signal output variable, had been designed to regulate the roasting temperature on the roaster. To evaluate its performance, the domain membership function of the input and output variables was varied. The design was then applied to the microcontroller-based control system hardware attached to the portable roaster. The test results show that the fuzzy logic control was able to regulate the roast temperature stably. With a varied roast temperature setpoint, the control system can follow and maintain the target with small temperature variation.