Pneumatic system for controlling and actuating pneumatic cyclic devices

Pneumatic system for cyclic control of fluid flow in pneumatic devic

Caudal pneumaticity and pneumatic hiatuses in the sauropod dinosaurs Giraffatitan and Apatosaurus

Skeletal pneumaticity is found in the presacral vertebrae of most sauropod dinosaurs, but pneumaticity is much less common in the vertebrae of the tail. We describe previously unrecognized pneumatic fossae in the mid-caudal vertebrae of specimens of Giraffatitan and Apatosaurus. In both taxa, the most distal pneumatic vertebrae are separated from other pneumatic vertebrae by sequences of three to seven apneumatic vertebrae. Caudal pneumaticity is not prominent in most individuals of either of these taxa, and its unpredictable development means that it may be more widespread than previously recognised within Sauropoda and elsewhere in Saurischia. The erratic patterns of caudal pneumatization in Giraffatitan and Apatosaurus, including the pneumatic hiatuses, show that pneumatic diverticula were more broadly distributed in the bodies of the living animals than are their traces in the skeleton. Together with recently published evidence of cryptic diverticula--those that leave few or no skeletal traces--in basal sauropodomorphs and in pterosaurs, this is further evidence that pneumatic diverticula were widespread in ornithodirans, both across phylogeny and throughout anatomy

Technique of pneumatic pest control – analyses and a new device

Pest control in organic production of berries, potatoes and vegetables usually employs spreading technique of registered phytopharmaceutical agents. This technique may be supported or even replaced by pneumatic pest control. Pneumatic pest control means suction of pest using a vacuum device similar to a home vacuum cleaner. Up to now there is no evaluation of pneumatic pest control available from an agricultural engineering point of view. This paper concerns the following questions: Which techniques of pneumatic pest control are available and how may these techniques be improved in terms of technical and physical parameters? Based on the answers a new device design is presented

Pneumatic PID with Ultrasonic Distance Feedback

Indiana University Purdue University IndianapolisIndiana University–Purdue University Indianapolis (IUPUI) is initiating a new course to the Electrical & Computer Engineering Technology (ECET) Curriculum in the spring of 2019, this course is Advanced Process Controls. The lab curriculum for this course needed a functional application to demonstrate the use of a proportional–integral–derivative controller (PID). The lab location for this course has one important limitation, specifically no use of water; therefore, our design integrates the use of pneumatics. Using the lab’s existing Rockwell Automation PLC and software package, this design uses the PLC’s PID instruction to maintain an extension length on a pneumatic single acting cylinder. This closed control loop consists of the PLC and analog I/O card, an ultrasonic distance sensor, one pneumatic cylinder for the controlled variable, one pneumatic cylinder as a disturbance, and two Proportion-Air QB1X analog controlled pneumatic solenoids. The final design in summary, uses the ultrasonic sensor to provide feedback to the PID with the current extended length of the pneumatic cylinder. This establishes any error, and the properly tuned PID uses this feedback to respond accordingly to ensure the desired extension length of the cylinder is maintained.Electrical Engineering Technolog

Compensating for pneumatic distortion in pressure sensing devices

A technique of compensating for pneumatic distortion in pressure sensing devices was developed and verified. This compensation allows conventional pressure sensing technology to obtain improved unsteady pressure measurements. Pressure distortion caused by frictional attenuation and pneumatic resonance within the sensing system makes obtaining unsteady pressure measurements by conventional sensors difficult. Most distortion occurs within the pneumatic tubing which transmits pressure impulses from the aircraft's surface to the measurement transducer. To avoid pneumatic distortion, experiment designers mount the pressure sensor at the surface of the aircraft, (called in-situ mounting). In-situ transducers cannot always fit in the available space and sometimes pneumatic tubing must be run from the aircraft's surface to the pressure transducer. A technique to measure unsteady pressure data using conventional pressure sensing technology was developed. A pneumatic distortion model is reduced to a low-order, state-variable model retaining most of the dynamic characteristics of the full model. The reduced-order model is coupled with results from minimum variance estimation theory to develop an algorithm to compensate for the effects of pneumatic distortion. Both postflight and real-time algorithms are developed and evaluated using simulated and flight data

Electropneumatic transducer automatically limits motor current

Pneumatic controller regulates the load on a centrifugal freon compressor in a water cooling system, thus limiting the current input to an electric motor driving it. An electromechanical transducer monitoring the motor input current sends out air signals which indicate changes in the current to the pneumatic controller

Total-pressure measurement in pulsating flows

Pneumatic-type probe was used as comparison instrument with total pressure tubes to determine true average pressure and, thus, to determine if nonlinear averaging effects were significant. Since pneumatic probe is more complicated to use than a total-pressure tube, it is used only as a comparison instrument to determine extent of averaging effects