Digital Control for the Air Pressure with Multi-Characteristics Selection


The paper deals with a preparatory research stage for controlling the air pressure inside a small tank by various characteristics and algorithms. Basic elements both for the hardware design and for the software support are presented. The experimental platform brings together parallel solutions: a microcontroller board using a PICTM 16F877 chip from Microchip and an industrial controller from HoneywellTM. The functionality of the platform will be tested in this stage by the on-line commutation of the control characteristics IN (pressure error) – OUT (PWM control for the air pump). A set for the available characteristics of the controller is stored in software. For a fast design with simulation and debugging capabilities, the author used FlowcodeTM of Matrix Technology Solutions – an Integrated Development Environment with a Very High Level Programming Language. Future research works are intended for some fuzzy control algorithms that could adapt and optimize the control accordingly the dynamic of the process. The main components of the platform are, besides the controllers mentioned above, an industrial pressure sensor, a compressor, the pressurized container and some standard pneumatic devices for a safe operation. Both the hardware and the software design are made so that besides the research aims, the platform could be a flexible and multi – purpose didactic tool for the students. images