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This article presents an overview the various types of pneumotachometers, the device used for measuring respiratory flow. It also presents their underlying principles, their strengths and weaknesses, their calibration procedures, and the methodology used to evaluate their dynamic characteristics.

A feedback control system for incorporation into an Engineering Technology controls laboratory has been developed. The purpose of developing a working control system is to reinforce controls theory taught in the classroom. A control system for positioning an air cylinder driven load platform was selected for the design. By controlling the height of the column of air in the air cylinder and regulating the pressure applied to the air cylinder piston, the platform could be positioned anywhere within the range of the air cylinder travel. To demonstrate the control capability of the system, random load disturbances were generated by adding and removing laboratory weights to the platform, with the desired setpoint position maintained. The instructional benefit of selecting a position control system was that the reaction of the control system could be readily observed as the platform returned to the set point position.

This paper presents a fluidic device capable of generating electrical micro-power from a steady air pressure source. The Fluidic Driven Piezoelectric Generator (FDPG) relies on a fluidic pressure-controlled oscillator, a fluidic linear proportional amplifier with its output ports connected to its input ports, to convert a steady air pressure into an oscillating air pressure. The piezoelectric device then converts the oscillating air pressure into an AC electrical voltage that is available for rectification and subsequent source of electrical power. This project has demonstrated that the FDPG produces 0.55W of electrical power, with an air pressure supply of 2.0 psig. This translates to an efficiency of 35%. This paper compares the predicted power level output of an analytical model to the proof-of-concept plastic model. The fluidic oscillator model was implemented in an equivalent electrical circuit using PSPICE. This approach has applications in remote or portable pneumatic applications where intelligent instrumentation and control are needed yet no battery or auxiliary electrical power is available to drive an electronic microcontroller.

Central. He is currently completing his Master's degree in Alternative Energy Technologies at ASU. ASU-PTL is the only accredited design qualification laboratory in the United States. ASU-PTL has tested more than 3000 PV modules and issued more than 280 qualification certificates. ASU-PTL participates in the development of national and international standards of ASTM, IEEE and IEC.