In this paper, some new achievements of Kagawa's researches on pneumatic techniques and applications are introduced. One of them is concerned with a low noise pneumatic resistance. In regard to its basic principle, compressed air is blown out through a very thin radial slit structure to form laminar flow. By this means, aerodynamic noise caused by turbulence can be decreased to a much lower level comparing with other type resistances like orifice. The radial slit type resistance is applied to develop a new pressure regulator by making the gap thickness of radial slits adjustable, which is characterized by lower noise and less pressure fluctuation. Another proposal introduced in this paper is an unsteady mass flow generator which can continuously generate and control oscillatory flow at a frequency up to 50 [Hz]. An important component of the generator is an isothermal chamber in which the essential isothermal condition is preserved. Utilizing the mass flow generator yields many practical applications, for example, the developments of air power meter. Recently, Kagawa's research interest extended to analysis and development of pneumatic non-contact handling device. A new non-contact handling method called vortex levitation by using swirling air flow is analyzed in Kagawa's laboratory. Swirling air flow can form a parabolic negative pressure distribution to pick up a work piece and keep it stably levitate with a considerably thin gap under the device. Furthermore, it is confirmed that a work piece will vibrate while being picked up and its vibration can be damped to zero due to a damping effect.

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Water hydraulics is an old technology area, which has been used already hundreds of years. Earliest applications where water was used as power transmission medium are known already from 2000 years ago. Modem water hydraulics can be comprised as a technology area where new design, material and control technologies are applied to water hydraulic systems. In 1990's very much research and development of water hydraulic systems and components were carried out in several laboratories in many countries. During the new millennium the research efforts has been a little bit smaller, but the continuously rising concern about globe and global climate change has also increased the interest on water hydraulic applications. This paper describes the actual research activities related to development of water hydraulic components and systems. The main focus areas are discussed and the challenges and possible solutions of each subject are analyzed. Water quality aspects, component technology, control aspects and also applications are covered. Also some analysis about water hydraulics' possible role in climate change process and energy saving are presented.

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Bosch Rexroth (BR) is worldwide player in hydraulics. And we are approaching each country to meet with local requirements. Japan is one of our target markets. Bosch Rexroth Corporation (BR-Japan) is strong position in Japan for mobile applications. In parallel, industrial is also our important profitable market. This paper presents BR and BR-Japan activities in industrial application, especially steel, press, test machine, marine, power generation. Additionally new products and system are introduced.

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The Hanshin-Awaji Earthquake (January 17, 1995) clearly demonstrated that the occurrence of very strong ground motion in the area near to the seismic faults is capable of causing severe structural damage beyond general estimation. It has emphasized the importance of earthquake engineering research into why and how structures collapse in real earthquake conditions. Considering the lessons learnt from recent earthquake disasters, National Research Institute for Earth Science and Disaster prevention (NIED) plan to construct the 3-D Full-Scale Earthquake Testing Facility (E-Defense is the nickname of this facility), which will be able to simulate the process of destruction of structures under the condition of real strong earthquake motions. The basic performances of E-Defense are maximum lording capacity 1, 200 tons, maximum velocity 200 cm/s and maximum displacement 2 m p-p for two horizontal excitations and maximum velocity 70 cm/s, maximum displacement 1 m p-p for vertical excitation to realize destructive ground motion. The driving energies are mainly produced by the hydraulic power system, which is consisted 10 horizontal actuators, 14 vertical actuators, 20 main-accumulator units, 4 gas-engine units, oil supply system (include piping system) and others. The construction has begun at early 2000, five year after the Hanshin-Awaji Earthquake and was completed at the beginning 2005, ten year after that Earthquake.

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Recently developed construction machinery continues to advance from machines only capable of performing a stated task or function to machinery that provides automatic feedback regarding where and how the equipment is being used and the unit's current status. A number of such construction machines equipped with optional computerized construction features have even proved capable of interpreting construction designs and automatically regulating tools such as bulldozer blades. These new developments have led to conventional approaches to construction-such as continually interrupting operations in order to take measurements and check the project's finished status-no longer being necessary, thereby allowing for extremely effective and streamlined operations. In this study I will present specific examples of the application of this information technology to construction machinery and consider how such construction machinery will continue to advance.

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After second oil shock in 1978, fuel consumption cost has become an important evaluation factor for construction machinery, many improvements have been made to increase machine efficiency [1]. Recent year, as the Kyoto Protocol get effective, further effort on fuel consumption cut or CO2 cut is required for all machine makers. As the success of the hybrid system in automobile, construction machinery makers also put a lot of force on research to apply the hybrid concept in their own machines. This paper introduced the research and development of hybrid machinery in Hitachi Construction Machinery Co. Ltd, and also discussed the problems in this field.

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A series hydraulic hybrid drive train for application in a passenger car is described. This ‘Hydrid’ drive train features an in-wheel hydraulic motor in all four wheels, hydraulic transformers for power control and hydraulic-pneumatic accumulators for energy storage and power management. The hydrostatic components are based on the highly efficient floating cup principle. The result is an efficient all-wheel drive vehicle with variable traction control on the front and rear axis. The fuel economy and the CO₂-emission of the drive train are calculated for a mid-class sedan while driving the New European Driving Cycle (NEDC). The efficiency of the hydrostatic components is derived from efficiency measurements of the floating cup pump.

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An automatic power steering control system is modified to a tractor of 66kw engine power and using a navigation system of optical fiber gyroscope (IMU) and real-time kinematic GPS which are hybrid combined, the movement of the vehicle in the field is analyzed dynamically using a kinetic movement model of tractor to determine the parameters of the model. The tractor equipped with a planter was successfully controlled and was able to trace the target line correctly within 10cm by the method of adaptive travel control using the movement model of the vehicle considering the hydraulic time delay of the power steering mechanism.

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Displacement-controlled actuators, advanced continuously variable transmissions and hydraulic hybrid power trains represent new technologies for mobile hydraulic machines, off road and on road vehicles. These new technologies allow major fuel savings and reduced emissions, but they change the performance requirements of positive displacement pumps and motors. Additionally, the market demand for positive displacement machines will increase. This paper briefly discusses these technology trends and the impact on existing pump and motor designs. The three major challenges are efficiency improvements, noise reduction and advancements in pump and motor control. Examples from the author's research team documenting the progress in computer modeling of piston pumps and motors will be given.

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Introduce KOMATSU's newest hydraulic systems and components for medium-sized bulldozer, which includes electronic controlled HST (Hydro Static Transmission) and hydraulically drive fan system. Electronic controlled HST consists of tandem piston pumps and two inside-shoe type final drives. Inside-shoe type final drive consists of bent axis type piston motor and 2 stage planetary reduction gear. Hydraulically drive fan system consists of variable piston pump common with work equipment pump and in-fan type fixed motor. This system is also electronically controlled. By using these hydraulic systems and components, layout flexibility and vehicle design flexibility are drastically improved, therefore this bulldozer can get unrivaled blade visibility and productivity at the same time.

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The development of fluid power systems for use in agricultural and construction machinery faced in the last years a substantial contribution due to the increasing role played by electronics. The scenario of the next years in agricultural and construction will be very much influenced by legislation constraints in terms of environmental compatibility, noise emission, energy usage and recyclability. The new set of requirements in terms of safety level for machines, described in documents like ISO 15998: 2008 will change the boundary conditions for machine design, requiring a deep investigation at system level, which will force a change in the design perspective for fluid power components. The new possibilities given by an extensive use of embedded electronics, advanced architectures and system level design of machines will be investigated and described trying to highlight threats and opportunities for next generation of products.

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The status and development tendency of construction machinery in china in recent years will be introduced; especially the outputs and performance level of the main products such as excavator, loader, crawler crane, truck crane, road roller and rotary drilling rig. Then the application of new products from internal corporation is analyzed and the research and development tendency of homemade hydraulic components of construction machinery field are also included. This paper introduces not only the national product standards of construction machinery but also the national policies and regulations for energy saving and pollution reduction in China.

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A numerical model of reciprocating fluid power seals has been developed. It has been applied to a variety of hydraulic rod seals, although it could also be used to simulate hydraulic piston seals as well as pneumatic seals. The model is soft elastohydrodynamic and consists of coupled fluid mechanics, contact mechanics, deformation mechanics and thermal analyses. Results for typical rod seals show that these seals operate with mixed lubrication between the rod and seal surfaces, and that the roughness of the seal plays a major role in determining the leakage characteristics of the seal. For a given seal design and set of operating conditions there is a critical seal roughness, below which there will be zero net leakage per cycle and above which the seal will leak.

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In water hydraulic systems, requirements for better energy efficiency call for the development of variable displacement axial piston pumps. Most axial piston units utilizing water as pressure medium lack the possibility of adjusting the swash plate tilt angle. because of difficulties in constructing robust water compatible swash plate pivot bearings. Without smooth enough adjustment motion, the lubrication conditions between the swash plate and the piston slipper pads become disturbed and loss of fluid film may lead to early pump failure.
This study reports on measurements made with a test rig built for investigating tribological phenomena in variable displacement axial piston pumps. In the tests, the effects of changing the swash plate tilt angle were measured in a test setup with constant high pressure which loaded the piston. Lubricating film thickness and lateral force acting on the piston were measured together with changes in these quantities in response to changes in swash plate tilt angle.

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In order to apply the water hydraulic drive system to the precision die casting machine, the system with accumulator and logic valves are examined. As the pressure medium, water is environmental friendly, but it has disadvantage, e.g. leakage due to low viscosity, low lubricity and so on.
In this report, the friction force acting on logic valves were taken into account in the mathematical model, because for the purpose of prevention of leakage on logic valve two or three 0-ring seals were used instead of labyrinth seal used in oil hydraulic logic valve. The validity of the mathematical model is assured by experimental results. Afterward the model is introduced into the mathematical model of whole high speed cylinder drive system and characteristics of the system is examined.

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The paper introduces three levels of details in the analysis of losses in hydrostatic drives which are carried out at IFAS of RWTH Aachen University (Germany). The first level of detail investigates the over-all system efficiency, the second level is focused on components while in the third level of detail the tribological contact in hydrostatic displacement machines are analyzed. Due to an increased environmental awareness and rising energy cost energy efficiency becomes a crucial factor in system design, components and single tribological contacts. Therefore the efficient conversion of mechanical into hydraulic energy and vice versa is the main objective when developing e.g. mobile construction machinery. An increase in the energy efficiency of hydraulic pumps, motors, valves and cylinders directly leads to significant reduction in energy consumption of hydrostatic drive lines and working kinematics. From the system point of view the power consumption of the diesel engine, as the power source of most mobile machinery, has to be reduced in order to increase tank-to-wheel efficiency. Modern management strategies for mobile machinery have to include diesel engine, drive line and working hydraulic with focus on an efficient operation of the engine.

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This research deals with master-slave control of a teleoperated hydraulic construction robot. In this system, the master consists of two joysticks, and the slave is the hydraulic construction robot (including the fork glove, boom, arm, and swing, driven by hydraulic actuators). In a previous research, the authors proposed a force feedback method based on position-velocity control, in which the cylinder velocity is proportional to the position of the joystick. The purpose of this research is to conrm the effectiveness of the force feedback method usinbehavioral measures and subjective indexes. An experiment was conducted to evaluate operational performance, confirming the effectiveness of the force feedback control system.

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We have developed a novel energy-saving hydraulic pump system Super Unit that comprises a high-efficiency motor, low-inertia pump and an inverter controller (We call this type of system ‘hybrid’). Compared with conventional hydraulic pumps each driven by a constant speed induction motor, our novel hydraulic pump system driven by a high-efficiency variable-speed IPMSM (Interior Permanent Magnet Synchronous Motor) features energy-saving of 40% or more when used for an injection molding machine which is a typical application of this new pump system.
By means of a pressure feedback control function and run speed control software on the controller, the pressure and fl ow rate of the hydraulic fluid are accurately controlled according to a command from the controller of the molding machine. This control software allows a high-torque high-precision motor to drive a low-inertia pump: as a result, high-speed high-response control of hydraulic actuators is realized, thereby the quality of molding products obtainable from injection machines controlled by our system is higher compared with quality resulting from conventional systems. A series of our variable-speed pump system products adopting hybrid hydraulic pressure technology are available for NC lathes, machining centers and other industrial machines such as a press machine.

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This paper introduces the air cushion pressure control of the 140m Techno Super Liner (TSL), which Mitsui Engineering & Shipbuilding Co., Ltd.(MES) has constructed. TSL is an air-supported catamaran ship, which contains pressurized air between rigid side hulls. The ship dynamic performance is investigated through simulations, for the first, which is based on 3DOF motion (Heave/Pitch/Roll) and air cushion dynamics. It was performed for both model and full scale in various wave headings. The scale effect is discussed through simulation results. Then, the results of towing model tests in both regular and irregular waves are described. The model is equipped with lift fans and all the tests are carried out under the on/cushion conditions. The results of model scale simulations and model tests are compared and verified. With these results from the simulations and model tests, the design of the air cushion control system is discussed in terms of the fan stability and ship vertical accelerations. The basic concept of air-vent louver control is presented. As for the sea trial of the ship, it was successfully completed on October 12, 2005. Some of her splendid performances were demonstrated. A brief introduction of the trial is also presented in this paper.

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Injection molding machines typically use hydraulic or electric systems, the selection of which depends on the performance, energy saving, investment cost, etc. Although hydraulic systems have the major disadvantage that they are less energy-efficient, it is well known that they have the advantage of high response and high thrust required for the control of pressurization and pressure holding. This paper introduces a control system and an AC servo motor driven hydraulic pump that are full-hydraulic and can achieve higher energy saving efficiency and performance. It also reports the current market trend toward the application of the system in Japan and overseas.

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Automotive steering systems have gone through the transitions from non-assisted type to hydraulic-assist type, and then, to electric-assist type for its assist. Still, some issues are remaining to adopt the electric-assist type steering to heavier duty vehicles. Therefore, we are depending more on the technology of electrically controlled hydraulic power steering.
This paper covers the technical trends in regard to power steering (PS) energy saving, especially focuses on electronic control of hydraulic PS.

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From the social background of global warming issue, earth environment protection issue and the rise of oil price, the demand of the improvement of fuel economy and CO2 reduction to a vehicle is very high nowadays. Continuously variable transmission (CVT) adoption has been recently increased to respond such social demand. JATCO is now also expanding the lineup of CVT as new solution for vehicle automatic transmission. In CVT, the shift control hydraulic pressure is a little bit higher than that of conventional stepwise shifting automatic transmission. So, unstable behavior of pressure is sometimes caused, for example, pressure oscillation. Such issue should be solved in early development stage. In this paper, we would like to introduce the feature and the techniques of oil pressure control system of CVT as an example of latest hydraulic control system for automatic transmission. And we would like to introduce our recent simulation for the optimal design of hydraulic control system.

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This paper investigates power management strategies for hydraulic hybrid passenger vehicles. Parallel, series, and power-split architectures are modeled and explored in the Matlab environment using variable efficiency hydraulic pump/motor models. Results are presented using a rule-based strategy with ad hoc selection of engine on/off setpoints for the accumulator and transmission gear shifting. The dynamic programming algorithm is then used to determine the optimal trajectories for engine/hydraulics power splitting for each of the architectures over urban and highway drive cycles. Results are then compared to baseline simulation for improvement. Using the given vehicle parameters, the parallel architecture for both the urban and highway drive cycles was shown to be best. By decreasing the volumetric displacement of the hydraulic pump/motors for the power-split configuration, fuel economy can be improved with a corresponding decrease in acceleration.

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A number of design and manufacturing techniques have been established over the years to ensure reliable products for spacecraft fluid control. Designs and processes originally intended for spacecraft chemical propulsion now have applications in electric propulsion as well as missile defense. The common element in each application is manufacturing processes that ensure assembly cleanliness, reliability, and repeatability.

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This paper considers power transfer between two fluid power circuits such that a failing pressure in one of them is improved by power transfer from the other circuit. The two coupled axial piston machines are effectively driven by the pressure differential across the two machines and particular features are required for the unit to operate successfully. Steady state theory is presented that may be used to select the relative displacement ratios and the range predicted is compared with those typically found in aircraft applications.

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The recent technologies of hydraulics and flight controls have been progressing step by step. The research effort for establishing the technology to build 55.2MPa (8000psi) hydraulic system for practical use has begun to fruit around the world, and high-pressurizing is getting to be standardized, shifting from the conventional 20.7MPa (3000psi) system pressure. The system pressure is settling into 34.5MPa (5000psi), which is practical in both cost and performance with the appropriation of the existing parts and ground support equipment considered.
Also, ALL ELECTRIC AIRCRAFT (AEA) technologies proposed more than 20 years ago have begun to come into practical use, such as electric actuators for primary control surfaces, as improved are 270Vdc power source technology, the permanent magnet peformance for electric motors, the power transister capability for control device, and the reliabilities of mechanical parts such as ballscrews and bearings.
This paper discusses the application of new materials to aircraft such as piezoelectric, magnetostrictive, and shape-memory materials, which have recently become stabilized in production and begun to be applied in commercial fields other than aircraft industry.

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More Electric Aircraft (MEA) or All Electric Aircraft (AEA) is intensively researched and developed all over the world to reduce total Aircraft power consumption, and thus total operation cost. In MEA or AEA development, Aerospace Research and Technologies activity are focusing the area of Electrical Power system, Flight control, Engine system, Environmental Control System and Landing Gear System.[1] We are focusing the Landing Gear Actuation System and as our 1^st step we have developed prototype ELECTRO-HYDROSTATIC ACTUATOR (EHA) for Landing Gear Extension and Retraction System (LGERS) application. The prototype EHA was designed and tested to evaluate the performance, weight and reliability to apply the future Aircraft application. From our prototype model development, we have clarified the technical issues to be improved or considered in the future MEA or AEA application.

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This paper will outline the various stages in the design and development of advanced rudder roll stabilization system based high slew rate steering system. The slew rate means rudder angle change rate. First, this paper introduces a high slew rate steering system with Electric hydraulic system (EHS). The basic concept of EHS system is to combine the hydraulic power source system and actuator system with controlling the speed of electric motor of hydraulic pump depending on the condition required to the actuator. Next, this paper presents the adaptive rudder roll stabilization system based on a multivariate auto-regressive model that is called Multivariate Auto-regressive Rudder roll Control System (MARCS). Finally, conclusions and discussions based on full scales experiments are summarized.

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Environmental problems of global warming are common topics that relate to all people on the earth now. The effort of conservation of energy is already an obligation. The purpose is to reduce the amount of the CO₂ exhaust that occupies most of the heat-trapping gas that causes global warming. As for the oil hydraulic unit used for the production machine in the factory, the one of energy conservation or more is strongly requested.
In this paper, it proposes our two kinds of conservation of energy oil hydraulic units. After the problem for a current oil hydraulic unit is clarified, the applied technological means and the effect are shown with the application case such as machine tools and the press machines.

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Bosch Rexroth (BR) has three categories control valves. One is the standard proportional valve, second is high response control valve and final one is servo valve. These three valves are applied to feed back control system for position, speed, force and acceleration. In this presentation, each valves design and performance are explained. And also applied applications for testing machine by Bosch Rexroth are introduced.

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This research presents a new flexible bending machine and its practical applications. The proposed machine uses a new method. When tubes are fed into the fixed and mobile dies, they are bent by shifting the relative position of the mobile die. The bending radius is controlled by the relative distance and orientation between the mobile die and the tube. The bending angle is controlled by the length of the fed tube. This forming process has a big advantage. A change of the expected bending shape will need no change in the tooling system but only a new definition of the motion of the active die and the length of the fed tube. The active die movements are controlled by a 6-DOF parallel kinematics mechanism (PKM) with hydraulic servo drive. Making use of the PKM serves not only to achieve a complete motion along six axes but also to obtain a high dynamic motion of the bending machine. Application examples show that the bending machine can be applied to designer's interiors, universal designed products, and automotive parts. Until now these processes have been difficult to achieve using a conventional bending machine.

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Nowadays, hydraulic actuators play an important role in a modern industry where controlled force or position with high accuracy is the most significant demand. This paper presents a new kind of hydraulic load simulator (HLS) for conducting performance and stability test in the bench system where force control is important. The system model consists of a hybrid hydro-electric actuator and another hydraulic circuit generating disturbances. For the purpose of improving force control performance of hybrid systems, a robust force controller using Quantitative Feedback Theory (QFT) technique applied to the HLS is also proposed in this paper. The controller is designed to satisfy the robust performance requirement, tracking performance specification, and disturbance attenuation despite uncertainties of HLS. Experiments are carried out to evaluate the effectiveness of the proposed control method applied for hydraulic systems even in the large varying perturbation.

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New pneumatic actuators developed in the author's laboratory will be presented with their applications to new mechatronics. Examples of them are a pneumatic rubber actuator for compliant robots, a micro pneumatic tube actuator assisting the colonscope insertion, a pneumatic stepping motor with high torque and resolution, a pneumatic drive bicycle, an intelligent pneumatic cylinder which has encoder and micro CPU realizing local control and communication functions, and a new control method utilizing multiplex pneumatic transmission for pneumatic systems with multi-degrees of freedom.

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A novel fluid power actuator called Flat Ring Tube (FRT) is introduced in this paper. The mechanism of FRT is so simple that it only needs a urethane flat tube and water pressure power source. No valves or switches are required. Applying constant water pressure results in periodic oscillation of the tube. The frequency is proportional to the flow rate of water and inversely proportional to the tube length. By contacting the tube with a passively supported shaft, it rotates due to the periodic tube oscillation. This principle can also generate the linear driving force, when FRT is mounted so as to kick the ground. Such kind of performance can be also expected to stimulate the blood flow rate, when FRT touches on the skin of the human body appropriately. The experimental results showed us the developed wearable massage device could effectively improve both the circulation of the blood flow and the density of oxygen in blood, which resulted in let the people feel more comfortable than conventional massage devices.

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A unified control framework is proposed for the control of fluid powered human power amplifiers. Human power amplifiers are mechanical tools that humans operate directly and the human force is amplified hydraulically or pneumatically. The tool and the environment forces would therefore appear to the human as having been scaled down. Ideally, the assistive force is transparent to the human such that the tool should feel haptically like any other passive mechanical tool to the human. To ensure safety and coupling stability, it is helpful that the controlled human power amplifier interacts with the human opeartor and other environments passively. In the proposed unified control framework, the hydraulic or pneumatic actuator is controlled to interact virtually with a fictitious inertia. The control problem then becomes one of coordinating the velocities between virtual inertia and the actuator. Both processes of augmentation with virtual inertia, and coordination can be done passively; the latter via the energy preserving passive decomposition approach into locked and shaped systems. The overall control system can be shown to possess the needed passivity property. The control schemes for both the hydraulic and pneumatic cases have been experimentally implemented.

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This paper presents the research on the experimental testing system of the space docking HIL (Hardware-In-the-Loop) simulation, which is based on a Stewart 6-DOF (Degree-Of-Freedom) motion system. First of all, spacecraft dynamics is analyzed. Because of the under-damping characteristic, stability of the HIL simulation system is analyzed, and control strategy of the 6-DOE-motion system, which is based on the phase compensation, is put forward to improve system stability. The influence created by the frequency characteristics of the 6-DOE-motion system on the accuracy and stability of the HIL simulation system is also analyzed. The characteristics of the spacecraft dynamics and the accuracy and feasibility of the HIL simulation system are verified with a non-damp collision device.

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For most of the microelectronics industry history, optical lithography has been the backbone for continuing the trend of making features even smaller. The intention of immersion lithography is to increase the index of refraction in the space between the lens and wafer by introducing a high refractive index liquid in place of the low refractive index air that currently fills the gap. Because the liquid acts as a lens component during scan-step process, it must maintain a high and uniform optical quality. Thus, an immersion unit structure must be implemented to keep the flow field from leaking. After analyzing the mechanic of the flow-field in immersion lithography, an immersion unit structure with double gas-curtain sealing and gas-fuid mixing phase collecting was designed and implemented, featuring chemical surface characteristics. Experimental results were analyzed in terms of vacuum degree in collection antrum, input pressure for gas sealing, bubble-trap within flow field, double gas-curtain, double mixing-phase collection, surface characteristics of wafer.

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The paper focuses on the modeling of heat transfer in pneumatic systems. The main aim of this work is to represent these phenomena during the charge or the discharge of a tank for complex circuit simulation or for the identification of instantaneous mass flow rate.
In the first part, a macroscopic model will be proposed. It is based on the dimensional analysis theory. This approach enables the main heat transfer mechanisms to be identified according to flow conditions, pressure levels and tank shape. A relation between the corresponding dimensionless groups is then used to develop a general model for computing the heat exchange coefficient according to the system state and geometry. The identification procedure is presented and the first simulation results show good agreement between experimentation and theory.

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In the paper, a low friction pneumatic cylinder and a sliding table, and both of them are embedded with aerostatic bearings are designed. A low friction pneumatic table is constructed by combining the pneumatic cylinder and the sliding table. The characteristics for the friction force versus velocity of the pneumatic cylinder and the pneumatic table are measured. Moreover, a hybrid self-tuning fuzzy sliding mode controller with dead zone and load compensation is designed to precisely control the position of the pneumatic table. The experimental results have shown that the pneumatic table has positioning accuracy of 20 nm, the resolution of the pulse scale.

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