Pneumatic System Research Articles

Design of an Arbitrary-Order PID Controller for a Pneumatic Levitation System

In this paper, an arbitrary-order proportional-integral-derivative controller is designed to control a pneumatic levitation system. To do it, an integer-order proportional-integral-derivative controller is tuned using the Matlab/Simulink PID Tuning block. Subsequently, the Curve-Fitting method is applied to approximate the behavior of the arbitrary-order of the integral and derivative part associated with the arbitrary-order controller. The proportional, integral and derivative gains obtained from the integer-order controller are used during the design of the arbitrary-order controller. Numerical simulations are performed in Matlab/Simulink, demonstrating a better transient response of the nonlinear system in comparison with the use of integer-order controllers.

Alcon Constellation® Vision System

Alcon Constellation® is the most widely used vitreo-retinal surgical systems in the world, providing up-to-date technology for vitreoretinal surgery. This system has many innovative features. These features provide the ability to use high-speed, small-diameter and dual pneumatic vitrectomy probe systems, to give the surgeon the chance to intervene in the forward and backward movement speeds of the guillotine, to control the intraocular pressure sensitively during the operation, to have an internal endolaser, and to automate the intraocular gas mixture at the desired rate. The aim of the vitrectomy surgeon is to bring the retinal tissue to a normal anatomical position by cleaning it from other tissues without creating an iatrogenic tear. The first and most important condition for the surgeon to fulfill this task and to minimize the tissue healing problems that may occurs after surgery is the safe, efficient and rapid removal of vitreous from the eye and retinal tissue. The Alcon Constellation® system is the most up-to-date vitreoretinal surgical device platform available today, enabling the vitreo-retinal surgeon to consistently achieve these goals.

Exergy analysis of pressure reduction, back pressure and intermittent air supply configuration of utilization/expansion stage in compressed air systems

Despite their many advantages, industrial compressed air systems are characterized by high energy consumption and very low energy efficiency. This is primarily due to the oversizing of pneumatic actuators, leading to excessive compressed air consumption in the utilization stage. Various methods have been proposed in the literature to address this issue, which can be classified into three groups: supply pressure reduction, back pressure increase, and intermittent power supply. However, no exergy analysis compares these methods in the utilization stage of a pneumatic system was performed. In this study, we conducted an exergy analysis to compare the exergy consumption and exergy savings of different pneumatic system configurations: the classic configuration, supply pressure reduction, back pressure increase, and intermittent power supply. The paper shows the most key places in CAS in terms of exergy losses, which result mainly from dead volumes, outlet loss and oversizing of components such as directional control valve, distributed pneumatic line and actuator. Losses in those components can amount to over 80% of input exergy and can be reduced even 3–9 times. Exergy evaluation of oversizing configurations showed that the highest exergy savings were obtained for a back pressure configuration (77%) and intermittent air supply (75%). The exergy savings for the pressure reduction configurations amounted to almost 50%. The paper presents mathematical models for several individual pneumatic components, including the actuator, directional control valve, muffler, pneumatic line and pressure reducer. The demonstrated mathematical model and exergy analysis can play a instrumental role in evaluating the exergy efficiency and optimization of a pneumatic system.

Modeling and research of a magnetoelectric converter for hydro and pneumo actuators

Purpose. Presentation of the results of modeling and practical implementation of a magnetoelectric converter for hydraulics and pneumatics systems of the aerospace industry. Methodology. Calculations of three-dimensional magnetic fields are carried out with the Finite Element Method by JMAG program. The solution of the differential equations connecting the input voltage, current, magnetic flux and torque is performed by numerical integration. Results. As a result of calculations, the converter configuration was obtained. Tests of the prototype model of the converter confirmed the principle workability of the adopted design and design solutions in its development. Practical value. Tests of the converter prototype sample confirmed the fundamental performance of the adopted design and constructive solutions.

Diagnostic sample transport via pneumatic tube systems: data logger and their algorithms are sensitive to transport effects.

Many hospitals use pneumatic tube systems (PTS) for transport of diagnostic samples. Continuous monitoring of PTS and evaluation prior to clinical use is recommended. Data loggers with specifically developed algorithms have been suggested as an additional tool in PTS evaluation. We compared two different data loggers. Transport types- courier, conventional (cPTS) and innovative PTS (iPTS)- were monitored using two data loggers (MSR145® logger, CiK Solutions GmbH, Karlsruhe, Germany, and a prototype developed at the University Medicine Greifswald). Data loggers differ in algorithm, recording frequencies and limit of acceleration detection. Samples from apparently healthy volunteers were split among the transport types and results for 37 laboratory measurands were compared. For each logger specific arbitrary units were calculated. Area-under-the-curve (AUC)-values (MSR145®) were lowest for courier and highest for iPTS and increased with increasing recording frequencies. Stress (St)-values (prototype logger) were obtained in kmsu (1,000*mechanical stress unit) and were highest for iPTS as well. Statistical differences between laboratory measurement results of transport types were observed for three measurands sensitive for hemolysis. The statistical, but not clinical, differences in the results for hemolysis sensitive measurands may be regarded as an early sign of preanalytical impairment. Bothdata loggers record this important interval of beginning mechanical stress with a high resolution indicating their potential to facilitate early detection of preanalytical impairment. Further studies should identify suitable recording frequencies. Currently, evaluation and monitoring of diagnostic sample transport should not only rely on data loggers but also include diagnostic samples.

SYNTHESIS OF MINIMAL SCHEMES OF SYSTEMS CONTROL OF HYDRAULIC AND PNEUMATIC DRIVES

The existing schemes of command apparatus are presented. Their analysis is carried out and the shortcomings are indicated. The scheme of afundamentally new command apparatus is given, which can significantly reduce the number of its elements. The synthesis of the pneumatic controlsystem of the foundry machine was carried out on the basis of the design approach proposed by M. Cherkashenko, which as a result led to a reductionin the devices by 3.5 times. A graph of operations of the pneumatic control system of the molding machine is constructed. A matrix ofcorrespondences is obtained, which determines the correspondence between the signals that cause transitions and the complete input sets acting in thetransitions. Analysis of the matrix of correspondences made it possible to identify and eliminate contradictory transitions. On the basis of theelongations, a system of equations describing the scheme of the control system is synthesized. Further, minimization is performed due to factorizationand decomposition of equations, and obtaining equations in their final form. A diagram is presented pneumatic control system of the molding machine,consisting of a command apparatus containing three cells, five cylinders, two vibrators, six limit switches, a time relay and other devices. The circuitsimultaneously uses the functional and logical capabilities of limit switches, the possibility of implementing the functions of three variables bydistributors. Thus, the use of the proposed command apparatus, in contrast to the existing schemes of command apparatus, can significantly reduce thenumber of distributors in the synthesis of the command apparatus itself and significantly reduce the number of elements when using the chosenapproach to the design of circuits of pneumohydraulic control systems.

Design and analysis of coil spring suspension system using N4518 grade flux levitation for motor bikes

Riding comfort is of paramount importance when designing a suspension system considering vehicle dynamics & stability control. Generally, two-wheelers use springs, hydraulic and pneumatic-type damping mechanisms. The present work was a neoteric magnetic suspension system for two-wheelers that use both magnetic and spring cushioning effects to provide comfort to the rider. In this work, two Neodymium ferromagnetic materials were fixed inside the shock absorber cylinders facing same pole each other. The repulsive magnetic flux they produce when come closer due to shocking load was utilized as media for dampening the shock. The combination of permanent magnet with coiled spring has been utilized to enhance the cushioning effect against the shock transmitted due to acceleration on an uneven road condition. The designed suspension system was more efficient over other type of suspension systems, absorbs a greater number of shocks with high accuracy and had no leakage problem unlike in hydraulic and pneumatic system. The design was validated using 3D modelling and Ansys simulation. The beneficial software validation made the design tentative to work efficiently with less maintenance cost.

Pneumatic Transport System REGATA-2 for Automation of Activation Analysis at the IREN Facility, FLNP JINR

The IREN facility at the Frank Laboratory of Neutron Physics (FLNP) of the Joint Institute for Nuclear Research (JINR) is used for experiments to determine elemental composition of various samples by neutron activation analysis (NAA). A pneumatic transport system (PTS) REGATA-2 was implemented to automate the delivery of containers with samples to the irradiation position and back. The article describes the characteristics of the PTS, its adaptation for operation at the IREN facility, and also plans for subsequent modernization and future prospects. After the assembling of the system, the optimal parameters were chosen for irradiating the typical samples, and a calibration was created for a high-purity germanium detector, which let to consider the volume nature of the samples. Samples of archaeological ceramics from Kazakhstan were studied using the PTS. The features of the IREN facility let to use not only a neutron, but also a gamma-producing target. The first experiments on the qualitative determination of elements by gamma-activation analysis (GAA) were carried out, and the prospects for using the facility for these purposes were confirmed. The creation of the PTS let to automate the process of irradiation samples and increase the efficiency of research in NAA and GAA, especially for short-lived isotopes. It also reduces the negative impact of radiation on the human body.

PB0907 Study to Determine the Effects of Pneumatic Chute System Transport on Biophysical Properties and Functional Activity of Platelet Concentrates

PB0907 Study to Determine the Effects of Pneumatic Chute System Transport on Biophysical Properties and Functional Activity of Platelet Concentrates

To the analysis of the efficiency of pneumatic bus suspensions on the basis of Ural all-wheel vehicle

This paper presents the results of sea trials of a prototype bus designed for use in the Far North. The bus was developed on the basis of the Ural all-wheel drive vehicle. The tests were carried out in order to verify the effectiveness of the use of the pneumatic suspension system "with an opposite arrangement of longitudinal guide levers" to reduce the level of vibrations in the passenger compartment and in the driver’s seat in conditions of long-term traffic on roads of 4—5 categories. Keywords: bus, air suspension, tests, sensors, suspension arms, vibration level. Keywords: bus, air suspension, tests, sensors, suspension arms, vibration level

The Bullet Launcher with A Pneumatic System to Detect Objects by Unique Markers

The Bullet Launcher with A Pneumatic System to Detect Objects by Unique Markers

B-032 Total lab Automation Validation/Verification Protocol: First Step of Process Excellence Journey in Smart Core Lab in Kokilaben Dhirubhai Ambani Hospital & Medical Research Institute, Mumbai, India

Abstract Background The total laboratory automation (TLA) involves the integration, automation, consolidation and digitalization of pre-examination, examination, and post-examination processes. It is far simpler to introduce TLA in a lean, highly standardized smart core lab setting than it is to replicate complex procedures based on manual workflows, therefore harmonization/standardization is a requirement. In this era of modern clinical laboratory, a very important step with respect to the quality of the entire process is method validation/ verification. Hence, it is fundamental to verify/validate TLA process flow, new techniques, new methods and new test parameters.During laboratory accreditation process, the most frequently cited deficiency involves inappropriate PQ (Performance Qualification) and verification protocol. The main principles to the PQ laboratory test validation or verification protocol are Accuracy, Precision, Reference Interval, Detection Limit (LOD), Analytical Measurement Range (AMR) and Clinically Reportable Range (CRR), etc. Hence a clinically appropriate turnaround time is guaranteed via validation, which also provides accurate and precise readings. Methods Around 250 parameters, of biochemical and immunoassay for samples like serum/plasma/cerebrospinal fluid/urine have been validated/verified on this automated system. Clinical Laboratory Standards Institute (CLSI) and best practise checklist as per international and national accreditation bodies served as the foundation for verification. Following are the steps for verification. Analytical Accuracy: Run samples by both methods to evaluate bias. Verify Precision: Run 5 replicates per run for 5 days, at all levels of control sera. Check Reference Intervals: Representative 20 healthy individuals are selected. Verify LOB and LOD Values: Run 20 blank (zero calibrator) or low patient samples. Pneumatic System Verification Protocol: 20 samples carried manually by health care assistants and 20 samples transported via the pneumatic system. We have done sigma metrics of 250 parameters in the lab. Results With particular reference to Thyroid Stimulating Hormone (TSH), we have obtained the following results: For the Reference interval study, out of 353 volunteers recruited, 8 volunteer data were excluded (7 outliers, 1 abnormal TPO values). We obtained the reference interval of 0.53–4.489 μIU/mL, which is within the range specified by the manufacturer's reference range. A good level of analytical accuracy is demonstrated between the two instruments with r2 = 0.9938 having a coefficient of variation of 4.32%. The coefficient of variation values of precision for inter laboratory method comparison for lower and high-level values is 1.39% and 1.76% respectively, which is comparable with the manufacturers claims values. The coefficient of repeatability is 1.3442 is higher than 0.7 and hence considered as the two instruments having a good retest reliability. We observed more than six sigma performance of TSH. Based on Operational Specification (OPSpecs) Chart and Method Decision Chart sigma values of all the parameters are evaluated and quality control strategies have been defined. Conclusion Thus, validation of all biochemistry & immunoassay parameters in TLA set up of the smart core laboratory promotes an environment, emphasizing patient safety and quality patient care.

An adaptive impedance control method for polishing system of an optical mirror processing robot

AbstractTo solve the constant contact force control problem between the end tool of a 5 degrees of freedom hybrid optical mirror processing robot and a workpiece, an adaptive impedance control method for the pneumatic servo-polishing system of the robot is designed. Firstly, the pneumatic servo-polishing control system at the end of the robot is set up. Secondly, the impedance control method for contact force is investigated based on the mathematical model of the pneumatic servo-polishing control system. Additionally, the causes of steady-state error of impedance control are analyzed theoretically, and the calculation method for steady-state error of impedance control is deduced. Finally, an indirect adaptive impedance controller based on Lyapunov Stability Principle is developed to estimate the environmental stiffness and position online, so as to reduce steady-state error and realize the tracking of polishing contact force. The simulation and experimental results suggest that the adaptive impedance control method not only recognizes that the contact force of the robot is relatively constant during the polishing process but also has high control accuracy for the force, fast-tracking response for the abrupt force, and considerable adaptability to the variable environmental stiffness.

Sarcomere‐Inspired Multilayer Artificial Muscle Units for Hyperconfigurable Robotic Applications

Soft pneumatic biomimetic robotic systems excel at the specific application they are designed for, often to interact or navigate unstructured environments safely. However, redeployment to new purposes requires substantial resources, from redesign to revalidation. Despite most pneumatic artificial muscles surpassing the power and contraction performance of natural muscles, natural muscles largely remain unmatched in terms of their versatility and complex performance. This is likely due to artificial muscle's low effective strain and high radial expansion, limiting parallel operating efficiencies. To address these challenges, a class of compact versatile pneumatic actuators, called multilayer artificial muscle (MAM), that are capable of deployment to different applications through configurable modularity, is presented. The MAMs are biomimetically inspired by the sarcomere, the building block for natural muscle architecture. Similarly, MAM can extend and contract as well as be rearranged to mimic muscle‐like actions and functions, such as a caterpillar locomotion robot and an entire robotic arm. The MAMs are fabricated through multilayer, multimaterial, low‐cost additive manufacturing, which offers certain advantages such as higher extension, contraction force, and durability. MAMs have the potential to provide a crucial fundamental building block toward future versatile reconfigurable architecture.

THE COMPOSITION OF THE PNEUMATIC SYSTEM FOR LOCAL MULTI-CIRCUIT COOLING ON AUTO TRACTOR DIESEL PARTS JUSTIFICATION

A series of motor bench and non-motorized experiments conducted at the Department of Engines and Hybrid Power Plants of NTU "KhPI" showed the high efficiency of local air cooling of heat-stressed parts of internal combustion engines, in particular, parts of the exhaust valve assembly of the gas distribution mechanism in an automated mode. However, in the tests carried out, a stationary air compressor powered by a ~220 V mains was used with air accumulation in a large-capacity cylinder. The implementation of a local cooling system on power plants, mainly powerful trucks, requires the inclusion in the automatic control system of autonomous cooling, a pneumatic compressor installed on the vehicle with an electric drive, powered by the on-board power supply and accumulating air in a receiver with compact dimensions.
 A review of design solutions and analysis of the component composition of pneumatic systems of autotractor vehicles was carried out. The requirements for the quality and safety of pneumatic systems of vehicles and their elements are considered. The technical characteristics of air compressors are presented. The scheme of the pneumatic system of local multi-circuit cooling on autotractor diesel parts has been chosen. On the example of the selected air compressor with an electric drive Maximum Performance 24V from ARB (Australia), estimates were made of the operating time up to a working pressure in the receiver of 10 bar. The electrical load on the 24 V on-board network of the vehicle was determined in the form of an average current consumption per filling cycle. The maximum current consumption by the compressor is determined, the current consumption per hour is estimated under the condition of a proportional alternation of the cycles of filling the receiver and emptying it.

APPLICATION OF VACUUM SUCTION CASTING OF IRON-CARBON ALLOYS FOR THE PRODUCTION OF ENGINE PARTS

The use of vacuum suction casting technology for iron-carbon alloys for the production of internal combustion engine parts will improve their quality and wear resistance, preserve metal, and reduce emissions. The technology is widely used for non-ferrous alloys. At the same time, its implementation for iron-carbon alloys (including cast iron) in modern engine construction requires careful scientific and practical preparation. Problematic tasks arise when improving the pneumatic system of vacuum suction (large volumes of gas release), the stability of the metal pipeline (thermal overload in a high-temperature cast iron melt), and the stabilization of the casting microstructure (high-speed crystallization). The authors suggest using a specialized titanium alloy VT3-1 for the metal pipeline, for which the article calculates thermal loads during cyclic operation in the “Deep – take-out” mode for the use of cast irons of the SCH25 and VCH50-1.5 grades. For reliable operation of the metal pipeline and the absence of solidification of the melt on its inner surface, a thermal calculation method was develop, which allows determining the time of heat removal of overheating of the melt according to the diameter of the metal pipeline. The pneumatic system of the vacuum unit is supplement with a patented gas jet ejector, which, in combination with a powerful shop compressed air system, provides a full gas outlet. Applying the developed law of change in the discharge between atmospheric pressure and pressure in the mold cavity, the authors of the article regulate the rate of crystallization of castings, which makes it possible to form much smaller phases of perlite in the microstructure and reduce the presence of Ferrite. At the Enterprise "Pervomaiskdizelmash" using vacuum casting technology, blanks of guide bushings of engine valves 6CHN25/34 made of cast iron SCH25 and VCH50-1,5, as well as oils of piston rings made of cast iron VCH50-1,5 were obtained. The obtained parts showed an increased service life by 15-30%. Vacuum casting technology is recommend for iron-carbon alloys in the production of engine parts.

Multi-state, three-way, normally open mini valve based on 3D printed flexible magnets using origami-inspired magnetization

Electromagnetic mini valves for controlling pneumatic soft actuators are attracting widespread interest in recent years. However, it is known that the traditional electromagnetic valves on the millimeter scale generally have three or fewer working states, and their moving parts are usually permanent magnets with a special shape that needs expensive manufacturing. To overcome these problems, this study aims to develop a mini valve with four working states based on flexible magnets at a low fabrication cost. We take full advantage of low-cost 3D-printed magnets’ physical and magnetic properties and improve their performance through origami-inspired magnetization. A fixed-beam-structure flexible magnet is proposed to control this valve via deformation so that valve’s two sides can be driven independently, resulting in four working states. Compared with conventional sintered magnets, 3D printing magnets can be manufactured quickly and affordably. Due to the proposed valves’ more operating states than the state-of-art three-way ones, they are proven to reduce the number of small control elements in the pneumatic system. The maximum flow rate of the valve at 5 kPa air pressure was 0.81 l min−1 at the power consumption of 20 W. This mini valve has the potential in controlling multi-degree-of-freedom pneumatic soft actuators.

Design and Verification of an Automated Pressure Mapping System and Modulating Air Cells for Pressure Ulcer Prevention

This research focuses on developing an intelligent air mattress prototype based on commercially available alternating pressure air mattresses to prevent pressure ulcers. Force-sensitive resistors (FSRs) are installed under each air cell to measure interface pressure values occurring at different parts of the body. These collected values are then used to create pressure maps, indicating areas of high overpressure. The prototype incorporates a smart pneumatic control system divided into seven functional areas: head, back, waist, buttocks, thighs, calves, and heels. All operations are performed using LabVIEW software.

A Portable Device for I-V and Arrhenius Plots to Characterize Chemoresistive Gas Sensors: Test on SnO2-Based Sensors.

Chemoresistive nanostructured gas sensors are employed in many diverse applications in the medical, industrial, environmental, etc. fields; therefore, it is crucial to have a device that is able to quickly calibrate and characterize them. To this aim, a portable, user-friendly device designed to easily calibrate a sensor in laboratory and/or on field is introduced here. The device comprises a small hermetically sealed chamber (containing the sensor socket and a temperature/humidity sensor), a pneumatic system, and a custom electronics controlled by a Raspberry Pi 4 developing board, running a custom software (Version 1.0) whose user interface is accessed via a multitouch-screen. This device automatically characterizes the sensor heater in order to precisely set the desired working temperature, it acquires and plots the sensor current-to-voltage and Arrhenius relationships on the touch screen, and it can record the sensor responses to different gases and environments. These tests were performed in dry air on two representative sensors based on widely used SnO2 material. The device demonstrated the independence of the Arrhenius plot from the film applied voltage and the linearity of the I-Vs, which resulted from the voltage step length (1-30 min) and temperature (200-550 °C).

Design of Backstepping Sliding Mode Control for a Polishing Robot Pneumatic System Based on the Extended State Observer

Due to advantages such as a high power-to-weight ratio, a simple structure, and low cost, pneumatic systems are widely applied in automation. However, precise position control of pneumatic actuators is challenging because of factors such as friction, compressibility, and external disturbances. This paper presents a backstepping sliding mode control (BSMC) strategy based on the extended state observer (ESO) for pneumatic cylinder position tracking. A nonlinear model of the pneumatic system is first established, then system states and disturbances are estimated by an ESO, next the BSMC approach is developed using backstepping method and sliding mode control theory, and the stability of the ESO and controller is analyzed using Lyapunov theory. Finally, simulations and experiments on a pneumatic testbed are performed to compare the effectiveness of the proposed approach with PID control. The results show that the proposed strategy improves tracking accuracy and robustness against disturbances, with a 77.04% reduction in root mean square error (RMSE). This research provides a promising control solution for automated pneumatic polishing robots.