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Microfluidics are crucial for managing small-volume analytical solutions for various applications, such as disease diagnostics, drug efficacy testing, chemical analysis, and water quality monitoring. The precise control of flow control devices can generate diverse flow patterns using pneumatic control with solenoid valves and a microcontroller. This system enables the active modulation of the pneumatic pressure through Arduino programming of the solenoid valves connected to the pressure source. Additionally, the incorporation of solenoid valve sets allows for multichannel control, enabling simultaneous creation and manipulation of various microflows at a low cost. The proposed microfluidic flow controller facilitates accurate flow regulation, especially through periodic flow modulation beneficial for droplet generation and continuous production of microdroplets of different sizes. Overall, we expect the proposed microfluidic flow controller to drive innovative advancements in technology and medicine owing to its engineering precision and versatility. [ABSTRACT FROM AUTHOR]

To improve the seedling-picking efficiency of the vegetable transplanter and reduce the damage rate of the seedling pot, a reciprocating seedling-picking device driven by full air pressure was designed. In this paper, the structure and working principle of the pneumatic seedling-picking device are introduced. Through the mechanical analysis between the seedling-picking claw and the seedling pot, working parameters such as the stroke and driving force of the pneumatic seedling-picking claw clamping cylinder were determined. According to the action sequence of the seedling-picking mechanism, which is horizontally dispersed and longitudinally conveyed, the pneumatic control scheme of the seedling-picking and -dropping system was formulated. The simulation model for the control loop of the longitudinal cylinder was created with AMESim simulation software, and the simulation analysis was carried out. The Box–Behnken response surface design optimization method was used to determine the best operating parameters of the cylinder. The optimized peak value of shock vibration at the end of the cylinder was optimized from −65.64 mm·s−2 to 35.41 mm·s−2, proving that the optimization of pneumatic working parameters has a positive effect on the success rate of seedling picking. The bench test of the seedling-picking mechanism was conducted on 72-hole plug seedlings with two picking frequencies of 120 plants·min−1 and 144 plants·min−1, respectively, and the average seedling leakage rate, seedling damage rate, and seedling pot damage rate at different picking frequencies were counted. The experimental results show that under the two seedling-picking frequencies, the average success rate of seedling picking and throwing after optimization is increased from 96.4% and 92.4% to 97.9% and 95.3%, respectively. This is in line with the requirements of high-speed seedling picking and confirms the rationality of the seedling-picking mechanism design. [ABSTRACT FROM AUTHOR]

Electromagnetic mini valves have attracted great interest in medical devices for their excellent performance and high integration. In state-of-the-art research, most mini valves have only two working states, while certain ones featuring three to four working states necessitate multiple driving sources. To solve these problems, a novel tristable electromagnetic mini valve with three stable working states achieved by a single coil was proposed. The actuation mechanism of this mini valve mainly comprises a cylindrical magnet (CM) and a ring magnet (RM) coaxially arranged. In the absence of current through the coil, the stability of the magnets is upheld by their mutual repulsion and the attraction of the iron core. Upon modifying both the magnitude and orientation of the current, one of the magnets traverses from one terminus to another each time. The two magnets are either stationary at the start point or the endpoint. Thereby, four position relationships are formed, three of which are stable. The minimum response time and energy consumption are 3.75 ms and 0.013 J, respectively. The working pressure of the valve ranges from 0 to 200 kPa. The maximum flow rate and back pressure reach 10.5 L/min and 180 kPa, respectively. A tristable design contributes to lower energy consumption, and the three-working-state function actuated by a single coil facilitates a diminution in the size of the mini valve. Consequently, a diminished quantity of valves is realized for multiple degree-of-freedom pneumatic actuator control, which promotes the miniaturization of the whole system. The dimensions and performance of the proposed mini valve substantiate its potential in pneumatic medical devices. [Display omitted] • The three-way electromagnetic mini valve achieves three stable working states through a single coil drive. • A tristable design is realized by the attraction of the iron core and the repulsion between two magnets. • The CM flips during the transformation, thus forming four states, three stable working states and a transition state. • The considerable magnet repulsion keeps the magnets stable, thereby increasing the working pressure and back pressure. [ABSTRACT FROM AUTHOR]

This paper presents a T-junction microdroplet generator equipped with a pneumatic actuation for controlling the droplet size. The multi-layer device is compatible with rapid manufacturing using a desktop-based laser cutter to fabricate the fluidic and pneumatic layers. A T-junction fluidic layer sits at the bottom and the control layer consists of a pneumatic chamber, as well as inlet and outlet channels are placed at the top. Our results with pneumatic control showed that the generated droplet size is inversely proportional to the pressure inside the pneumatic chamber. Pneumatic pressure of up to 0.4 MPa showed a 38% reduction in droplet size compared to without control. The droplet size can additionally be regulated by controlling the relative flow rates of the continuous and dispersed fluid. Pneumatic actuation is advantageous, as it does not require additional fluid usage and the flow rate does not need to be ramped up to decrease the droplet size. The device presented in this paper with pneumatic control and fabrication ease provides an attractive method for microdroplet manipulation. [ABSTRACT FROM AUTHOR]

New methods and devices for pneumatic batching and control of a flow of granular materials are analyzed and described. Atypical approaches to the creation of the control algorithms are considered. Constructions of the actuating devices for volume systems and regulation of the rate of flow are proposed. Results of experimental investigations of automatic volume dosing devices (batchers) are presented. Recommendations for the selection of the structural and regime parameters of automatic volume batchers are given. [ABSTRACT FROM AUTHOR]

The paper reports design and development of a PLC-based controller for pneumatic pressing machine, which performs the most critical operation in an engine bearing manufacturing plant. The paper firstly overviews the manufacturing process of engine bearing and then discusses the need of automating the pneumatic press. The proposed automation system involves (a) speed control by replacing the conventional method with a variable frequency drive (VFD), (b) feeder and pusher control using PLC, (c) fault detection and safety measures, (d) and PLC-based sequential control of all the processes carried out on pneumatic press. The control system is based on MicroLogix-1000 PLC from Allen Bradley and the ladder logic program for it has been written on RSlogix-500. For the evaluation of the proposed control system, the PLC program was emulated on RSLogix Emulate-500 and the operations of the pneumatic press were simulated on FluidSIM-P. The results of simulation validate the design of PLC-based controller in general and digital input-output connections of the PLC and PLC program in particular. [ABSTRACT FROM AUTHOR]

Pneumatic yarn splicing is a complex process concerning the winding of multi-filaments in a spiral airflow field. In this study, the joint forming mechanism is revealed by experimental and numerical methods. The whole splicing process in a specific-design splicing device was captured by a high-speed camera. A renormalization-group k-ɛ turbulent model was also adopted to simulate the distribution of the airflow field in the mingling chamber. From experimental images and numerical results, the motion of the filament with one fixed-end and a joint forming mechanism was discussed in detail. It is found that different parts of a large aspect ratio filament present completely different behavior due to its flexibility. The free-end of the filament is wound around the opposite yarn under the impact of circumferential airflow. Meanwhile, the bending deformation occurs at the middle part of the filament owing to the strong impact of the injecting airflow, and then it is dragged toward the fixed-end of the filament by axial airflow to prevent the forming of a joint. It is believed that the initial overlapping length has a decisive role in the forming of the splice joint. A proper overlapping length is of benefit to achieve enough winding loops at the free-end of the filament to resist the dragging force exerted by axial airflow and obtain a successful splice subsequently. The splicing experiments with different overlapping length and inlet pressure were conducted to verify the correctness of this analysis. [ABSTRACT FROM AUTHOR]

Gas turbines are usually the core elements of numerous mechanical systems. Subsequent to the advancement of high efficiency and clean energy, gas turbine has a significantly growing role in different areas, such as aviation and marine propulsion systems, electric power stations, and natural gas and petroleum transportation. However, gas turbines are decisive in operating many industrial plants, and their accompanying maintenance costs are likely to be exceedingly high. A number of failures in the gas turbine components have been detailed and discussed in this paper, with a view to thwarting future breakdowns by suggesting specification for notable maintenance and utilisation of gas turbine components. This study puts forward Fuzzy Analytic Hierarchy Process (AHP) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) methods applied in failure detection of gas turbine components. This paper attempts to handle gas turbine components, which contain hydraulic–pneumatic equipment, electronic control equipment, and bearing equipment. Thanks to the assessment of specialists, heavily influenced by failures, gas turbine components have been decided. The results have proved the bearing equipment to have been the most effective alternative, as being ensued by hydraulic–pneumatic equipment and electronic control equipment. [ABSTRACT FROM PUBLISHER]

The article addresses results of analyses of design solutions and materials commonly used in gas springs for hydropneumatic suspension systems. The authors have discussed main advantages resulting from application of such a design solution in passenger car suspension systems. Fundamental correlations defining the parameters characterising a gas spring with constant gas mass have been referred to. Also materials used in the manufacture of selected gas spring elements have been described [ABSTRACT FROM AUTHOR]

This study developed a rehabilitation system that can improve the patient care services provided by physical therapists. Wristparalyzed patients were given arbitrary force through a six-Degree of freedom (6DoF) parallel mechanism composed of six pneumatic cylinders, and recovery training was performed. Each pneumatic cylinder was used to apply force control using a pulse width modulation control, and the force of the 6DoF direction was directed to the wrist of the patient. The thrust force of each cylinder and the force of the 6DoF direction of the parallel mechanism were analyzed. The analysis results conformed well to the experimental results. The developed rehabilitation system was designed to help a physical therapist remotely treat multiple patients at the same time. To monitor the operation of the parallel mechanism of each patient's side, a 3D computer graphic model was created through OpenGL. The movement of this model was investigated to further examine the movement of the 6DoF direction of the parallel mechanism. Results confirmed that both movements can be controlled synchronously. [ABSTRACT FROM AUTHOR]

In this paper, an observability analysis for differential pneumatic pistons is presented, together with the design and implementation of linear observers of the Luenberger type. To avoid as much as possible the knowledge of the system model parameters, the generalized proportional integral (GPI) approach is employed for the estimation of unmeasured variables. Experimental results show the good performance of the proposed scheme. [ABSTRACT FROM AUTHOR]

The acoustic data measurement system and processing algorithm are developed to position a pneumatic impact machine in soil. The method is based on recording lag time of entry of acoustic signal generated on interaction between the pneumatic impact machine and soil in the receiver of multichannel measurement system relative to reference signal of the machine. The measurement system and the algorithm have been trialed in full-scale conditions. [ABSTRACT FROM AUTHOR]

The most common actuators used in servo-pneumatic systems are linear actuators consisting of a piston and a cylinder in the simplest form. Two parameters of the cylinder are usually known: the piston diameter and the maximum stroke. But there is typically no information available about the parameters and characteristics needed for mathematical modelling, e.g. friction, leakage, heat transfer or dead volume and these parameters must be determined experimentally. This paper presents a new methodology for dead volume identification in pneumatic linear drives with internal complex geometry. Dead volume, i.e. the gas volume when the piston has contact with the end cover, is important because otherwise an effective volume of zero would occur during simulations when the piston has reached an end position. Tests are carried out with the proposed new method on a DGPIL-25-360-AIF-KF-AV linear drive produced by FESTO. Based on the results, the proposed method can improve the accuracy of nonlinear models of servo-pneumatic systems. [ABSTRACT FROM AUTHOR]

The paper presents a multi-sensorial module containing several sensors (for pressure, temperature and flow measurement) and the afferent electronic block, that connects to the data bus of the served system. The use of this module in a pneumatic system leads to a simplification of its structure and maintenance. The concept, design and development of an experimental model of this module are considered. [ABSTRACT FROM AUTHOR]

The paper presents a multi-sensorial module containing several sensors (for pressure, temperature and flow measurement) and the afferent electronic block, that connects to the data bus of the served system. The use of this module in a pneumatic/hydraulic system leads to a simplification of its structure and maintenance. [ABSTRACT FROM AUTHOR]

The paper presents a novel pneumatic positioning system, designed around the concept of accurate positioning of a mechanical stopper for a pneumatic cylinder. This is performed by an electrical actuator, designed according to the high accuracy intended and the implied forces. [ABSTRACT FROM AUTHOR]

The paper addresses an analysis of the constructive solutions of pneumatic equipment that integrate sensors for different mechanical parameters. It also presents the actual trends and the perspectives in the field and points out the main problems that have to be solved in order to integrate sensors and corresponding electronics within pneumatic equipment. In the final section, the authors propose an original principle solution of a pneumatic proportional direction control valve with flow rate feedback control. The proposed construction can integrate two sensorial units that measure the flow rate, respectively the pressure on the two consumer circuits. [ABSTRACT FROM AUTHOR]

Micro motion tasks can be found in a wide set of applications, ranging from the assembly of small parts in the semiconductor industry to assisted surgery in medicine. Conventional actuation systems for these types of task are based on the existence of electromagnetic fields (servomotors) or on the existence of some kind of material shape alteration (piezoelectric actuators). Driven by the intrinsic advantages presented by pneumatic systems, such as low cost, the absence of heat or magnetic field generation and a wide range of operation, this article presents a different approach, based on the use of commonly available industrial servopneumatic components. Experimental results show that it is possible to correctly follow 5 µm step references within a 280 mm stroke, without any controller retuning and with mass load changes from 2.69 to 13.1 kg. [ABSTRACT FROM PUBLISHER]

Workpiece placing and removing for punching press operated by hand have low precision, low efficiency and poor security. The workpiece automatic placing and removing of punching press driven by pneunmtic is introduced in this paper. The overall structure and operating principle of manipulator are given. The pneumatic control and PLC program control are advanced to realize stepless speed regulation, overload protection and to complete complex actions easily. The substitute clamping jaw of manipulator is researched. The design shows the advantages such as simple structure, low cost, easy to operate and maintenance, high efficiency and reliability. [ABSTRACT FROM AUTHOR]

In order to build a 3D model environment of a pneumatic caisson for excavator operators and managers, a modeling and measuring 3D surface system of unmanned pneumatic caisson was presented in this paper. The whole system is based on two 3D laser scanners for the pneumatic caisson by acquiring the surface data of pneumatic caisson and successive data processing for surface reconstruction and measurement. Registration and reconstruction are also discussed in this paper. In order to convert two point sets into one common coordinate, Hough transforms were used to extract planes and then by using their parameters to register the two point sets. As for surface reconstruction using triangular meshing, a new method based on curves was presented. When combined with the real-time pose and location of the excavators, the 3D environment can be used as a “virtual reality” operating environment for excavation operators. The whole system has been applied in a pneumatic caisson of an underground project in a Shanghai subway, which proved to be working well, with less than 16-s work cycle (period of a single 180° 3D laser scan), at an estimated resolution of less than 20 mm. [ABSTRACT FROM AUTHOR]

The aim of the experiments reported in this paper was to evaluate the tribocharging phenomena that might occur in the annular ducts specific to the cyclonelike aspiration unit of a suction-type dilute-phase pneumatic transport system. The experiments were carried out with two types of powders, on two models of ducts, having the same geometrical characteristics but being built of different materials. It was found that the charge acquired by the particles strongly depends on the nature of the material of the annular ducts. This triboelectric effect might be effectively employed for the selective charging and electrostatic separation of granular or pulverulent mixtures of insulating materials. [ABSTRACT FROM AUTHOR]

Pneumatic actuators are attractive for robotic rehabilitation applications because they are lightweight, powerful, and compliant, but their control has historically been difficult, limiting their use. In this paper we present the pneumatic control system developed for Pneu-WREX: a pneumatically actuated, upper extremity orthosis for rehabilitation after stroke. The developed pneumatic control system combines several novel components to make the entire system stable, reliable, and backdrivable. These components, which are described in this paper, include: (1) a unique two-valve force control subsystem that keeps chamber pressure low (to reduce friction and energy consumption) and adaptively compensates for leakage; (2) a new servovalve characterization approach that uses experimentally measured data in a combined non-linear and least-squares regression to obtain a linear relationship between mass flow and valve voltage; and (3) a new approach to state estimation using accelerometers and a Kalman filter to obtain clean signals for use in a non-linear adaptive feedback control law. Experimental testing of the device demonstrates the efficacy of the developed pneumatic control system. [ABSTRACT FROM AUTHOR]

The article presents information on a research paper which focuses on the applications of pneumatic components like grippers and actuators. It is said that due to ease of use and relatively quiet operation, pneumatic automation technology is used in many industries including food, pharmaceutical, automotive, aerospace, plastics and electronic sectors. It is said that pneumatic components are long lasting and reliable, and they can be used in tens of millions of operational cycles. The paper also focuses on the use of pneumatic elements in automatic assembly operations.

In present, the withdrawal profiles at horizontal continuous casting plant is using a system which consists of a pair of parallel rollers electro-driven and executing a rotational movement with a sequential mechanism motor step-by-step reduction. The withdrawal roller has some major shortcomings: large size of the whole step by step motor-reduction requiring a pneumatic mechanism for raising the profile of the rolls, rolls are striated to pull the bar mold, which leads to visible traces on the profile shot. The proposed system uses instead of rollers (they have smaller surface contact) tanks that have adjustable horizontal surface contact plane. This profile provides a withdrawal force necessary to withdrawal without creating defects. [ABSTRACT FROM AUTHOR]

To suppress the influence of eccentric load on dynamic characteristics of rotary cylinder installed vertically, a speed stability index α, is proposed firstly. Then a solution method is presented to improve the speed stability by drilling a hole on the rotary shall of rotary cylinder, which connects one working chamber to the other within a rotary angle scope, and a mathematic model considering the connecting hole is built. An real-coded GA optimization design for the connecting hole based on the minimum α, is fulfilled. Simulation and test results show that the method can solve the velocity instability problem of rotary, cylinder efficiently. [ABSTRACT FROM AUTHOR]

In order to achieve a certain pneumatic clutch actuator in AMT system with lower cost. on the basis of advanced analysis of clutch control process and the characteristics of pneumatic control, a method is proposed, in which the pneumatic clutch actuator is driven by high-speed respond switch electromagnetic valve controlled by PWM, And the corresponding model-reference adaptive control strategy is established as well. Real vehicle road tests conducted by several drivers in different road conditions and environments prove the feasibility of the control strategy. And such experimentelectromagnetic va results also show the low cost and simple construction characteristics of such a pneumatic clutch actuator, which is the foundation of further industrialization. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a function approximation technique (FAT)-based adaptive controller is proposed for pneumatic servo systems with variable payload and uncertain disturbances. The system model is firstly described by a set of non-autonomous state equations with mismatched uncertainties. Since the uncertainties are time-varying and their variation bounds are not available, most traditional robust designs or adaptive strategies are not directly applicable. The FAT-based design is proposed here to estimate these uncertainties so that the closed-loop stability can be proved by using the Lyapunov-like theory. The problem in dealing with the mismatched uncertainties is circumvented by using the multiple-surface sliding control (MSSC) algorithm. Experimental results justify that the proposed scheme can give good performance regardless of various uncertainties. [Copyright &y& Elsevier]

Pneumatic actuation systems are widely used in industrial automation, such as drilling, sawing, squeezing, gripping, and spraying. Also, they are used in motion control of materials and parts handling, packing machines, machine tools, food processing industry and in robotics; e.g. two-legged robot. In this paper, a Neural Network based intelligent PI controller is designed and simulated to increase the position accuracy in a pneumatic servo actuator where the pneumatic actuator consists of a proportional directional control valve connected with a pneumatic rodless cylinder. In this design, a well-trained Neural Network provides the PI controller with suitable gains depending on feedback representing changes in position error and changes in external load force. These gains should keep the positional response within minimum overshoot, minimum rise time and minimum steady state error. A comparison between this type of controller with a conventional PI type shows that the position of cylinder using a conventional PI controller keeps jittering even when the cylinder reaches the required steady state. This is because of nonlinearities that exist in the pneumatic actuator. This jitter does not persist when a Neural Network based Intelligent PI type controller is used. [ABSTRACT FROM AUTHOR]

This paper reports on liquid (deionized water) microlenses that are intrinsically formed and integrated within microfluidics through pneumatic manipulation of fluids inside microchannels. Such microlenses are formed via liquid-air inter- faces of liquid droplets, which are pinned at T-shaped junctions of channels. In addition to being tunable in focal lengths (a few hundreds of micrometers to oo) along the microchannels parallel to the substrate used, these microlenses can uniquely be repositioned, removed, and reformed at predetermined locations of the T-shaped junctions within microchannets on demand under pneumatic controls. The design and formation of a microfluidic channel network for the in situ formation are first described. Then, the pneumatic control of the fluids, including the formation, movement, and size control of a lens droplet, is discussed, and the in situ formation processes for single and multiple liquid mi- crolenses are described. The in situ formation processes for a single microlens and a two-lens combination only take tens of seconds, eliminating various conventional microfabrication processes and multiple layers of materials. Finally, the detail of characterization of these microlenses is given. [2007-0 176] [ABSTRACT FROM AUTHOR]

Hydraulic and pneumatic components are widely used in vehicle semi-active or active suspension systems. These dynamic systems have certain non-linear and time-varying behaviours. It is difficult to establish an appropriate dynamic model for model-based controller design. Here, a novel neural network based sliding mode control is proposed by combining the advantages of the adaptive, radial basis function neural network and sliding mode control strategies to release the model information requirement. It has online learning ability for handling the system time-varying and non-linear uncertainty behaviours by adjusting the neural network weightings and/or radial basis function parameters. It is implemented on a quarter-car hydraulic active suspension system. The minimum number of radial basis functions required for this neural network is 5. The experimental results show that this intelligent control approach effectively suppresses the oscillation amplitude of sprung mass in response to road surface disturbances. [ABSTRACT FROM AUTHOR]

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This brief compares the performances of different operation strategies based on optimal scheduling and heuristic scheduling for heavy haul trains equipped with electronically controlled pneumatic braking systems. Train scheduling here refers to an open-loop control design that brings the train to a desired (steady-state) motion trajectory. A (closed-loop) cruise control is used to maintain a steady-state motion of a train. In train handling, energy consumption, speed tracking, and in-train force are concerns for transportation corporations. The last is particularly important for safe train running. An optimal train scheduling as well as an optimal cruise control can take these factors into consideration. A speed profile is assumed first. The objective of the study is to find optimal driving methodologies for an implementation of a desired speed profile with energy consumption and in-train forces considered. Simulation results show that optimal scheduling can improve the performance of the closed-loop controller, and that the 2-2 strategy, the electronically controlled pneumatic/independent distributed power mode, is the best of all strategies. [ABSTRACT FROM AUTHOR]

As opposed to traditional pneumatic linear actuators, muscle and rotational actuators are newly developed actuators in rotational and specified applications. In the current paper, these actuators are used to set up two-dimensional pneumatic arms, which are used mainly to simulate the excavator's motion. Fuzzy control algorithms are typically applied in pneumatic control systems owing to their non-linearities and ill-defined mathematical model. The self-organizing fuzzy controller, which includes a self-learning mechanism to modify fuzzy rules, is applied in these two-dimensional pneumatic arm control systems. Via a variety of trajectory tracking experiments, the present paper provides comparisons of system characteristics and control performances. [ABSTRACT FROM AUTHOR]

The paper presents three balancing mechanisms, which have been utilized as experimental systems in the control education of mechanical engineering students. Their uniqueness is the pneumatic drive, which makes them more affordable, simpler and more interesting to control. These balancing mechanisms are the inverted pendulum, the inverted wedge and the ball and beam, while the pneumatic infrastructure includes a variety of valves. This paper describes these experimental systems and some methods applied to control them. [ABSTRACT FROM AUTHOR]

The paper presents a number of original solutions of proportional pneumatic throttles. [ABSTRACT FROM AUTHOR]

The paper tackles the problems specific to the achievement of accurate pneumatic control systems and proposes a solution like this one. The solution is to combine open-closed position of simple pneumatic equipments as digital solenoid valves with an electric on-off control. [ABSTRACT FROM AUTHOR]

A pendulum and a method for correcting the restoring force of the pendulum are proposed for realizing an instrument based on the levitation mass method without the use of pneumatic linear bearings. As an example a material tester using the pendulum, which evaluates the mechanical response of general objects against impact forces, is developed. The characteristics of the restoring force are accurately determined using the same instrument under the free-swing condition without the object under test. To demonstrate the high performance of the developed instrument, the impact response of a gel block is accurately determined. The possible applications of the developed method are discussed. [ABSTRACT FROM AUTHOR]

This paper presents the implementation of a PID controller on a pneumatic system. [ABSTRACT FROM AUTHOR]

Abstract: This project deals with the study of electro-pneumatic systems and the programmable controller that provides an effective and easy way to control the sequence of the pneumatic actuators movement and the states of pneumatic system. The project of a specific controller for pneumatic applications join the study of automation design and the control processing of pneumatic systems with the electronic design based on microcontrollers to implement the resources of the controller. [Copyright &y& Elsevier]

In this study, the performance of the rotational speed control of a proportional-valve-controlled pneumatic motor is investigated. The main application field of the proposed prototype is the pneumatic tools, which are currently very important manufacturing devices. Generally speaking, it is usually quite difficult to obtain a satisfactory and precise speed control of a servo-pneumatic motor at a low rotational speed because of the nonlinear deadband and stick-slip friction inside the proportional valve. Therefore, the fuzzy-sliding mode controller is proposed. Experiment results show that the fuzzy-sliding mode controller is superior to the traditional PID controller, especially when the command input is set at a low rotational speed. This newly designed prototype may be utilised to develop advanced pneumatic tools. [ABSTRACT FROM AUTHOR]

The aim of this paper is to propose a general principle able to manage the supervision, coordination, and control problems of a large scale of multichain structures in dynamic and interacting tasks. The main originality lays in its modular feature. The number of chains and of joint per chain are indeed not restricted. The only assumption is that all the chains are linked to a principal element from which the dynamic stability will be computed. This is for example the case for multi-finger and multi-legged structures for which respectively the palm and the trunk represent the principal element. The principle consists in controlling the stability of this element and distributing the effort on the other chains to maintain the stability of the whole. To increase the compliant feature, we consider that each joint is pneumatically actuated. Each joint is then dynamically controlled to ensure the asymptotic stability of the local chain it belongs to. A global architecture is presented where each part is detailed. An example is then displayed showing the performances of a two-legged robot in the standing posture under external perturbation effects. © 2004 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Operating cycles of pneumatic puncher and pneumatic hammer with equal capacity of back-stroke chambers are compared. The advantages of pneumatic hammer are shown. Based on the experimental investigations, recommendations are made for selecting design parameters of pneumatic hammer. [ABSTRACT FROM AUTHOR]

The article presents a control system for a six-degree of freedom (DOF) anthropomorphic robot powered entirely by pneumatic actuators. The control uses digital valves driven by pulse width modulation (PWM) to regulate air flow to the actuators. The robot is equipped with position sensors, which are used to provide feedback signals for local fuzzy controllers actuating the individual servoaxes. Trajectory tracking is guided by a module, which computes the robot's inverse kinematics, generating the references for the servoaxes. Experimental results illustrated in the article indicate that the controller is effective both in controlling single axes, and in tracking a trajectory. © 2002 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]