Pneumatic Technology Research Articles

Simulation Study for Pneumatic Conveying Drying of Sawdust for Pellet Production

Pneumatic conveying drying (PCD) is a combination of heat and mass transfer and pneumatic handling technology. This technology has been extensively used in chemical, pharmaceutical, and food industries, as well as many others. The PCD technique is beneficial for agricultural products, because it can achieve high-quality drying with reduced heat damage in a very short time. In this study, one-dimensional and three-dimensional mathematical models for the drying of sawdust particles in a pneumatic dryer were developed and verified with experiments. The three-dimensional modeling was done with a computational fluid dynamics (CFD) package (ANSYS FLUENT, Ver. 13.0, Ansys, Inc.), in which the gas phase is modeled as a continuum using the Euler approach, and the droplet/particle phase is modeled by a discrete phase model with a Lagrange approach. One-dimensional analysis was performed in MATLAB (Ver. 7.0). The experiments were carried out to validate the model in a pneumatic dryer with a horizontal length of 1 m, vertical height of 1.1 m, and diameter of 0.14 m. Sawdust, a raw material used for producing pellets, was prepared from well-seasoned pinewood timber. The initial moisture content of the sawdust was 22% (wb). The hot air inlet temperature in the dryer was fixed at 100°C. The variations in air pressure, air velocity, air temperature, and particle moisture content were investigated along the length of the dryer. The final moisture contents of sawdust and air temperature were reduced by 2% (wb) and 5°C, respectively. The simulated values were in good agreement with the experimental values. The developed model was then employed for the design of a pilot-scale pneumatic dryer (length 7 m and diameter 0.14 m). The final moisture content of the sawdust particles was reduced to 14% (wb) when the dryer length was increased from 1 to 7 m. In addition, the modeling was performed using buffers in the pilot-scale dryers. The use of a buffer noticeably increased the drying efficiency.

Pneumatic Servo Bearing Actuator with Multiple Bearing Pads for Ultraprecise Positioning

With the increase in demand for semiconductor products, ultrafine linear patterning technologies for Large-Scale Integrations (LSIs) have been making progress. The requested positioning accuracy in such ultraprecise apparatuses is of nanometer order. To meet such specific needs, the research and development of a variety of actuators has been necessary. Our laboratory has developed a ‘Pneumatic Servo Bearing Actuator (PSBA),’ a novel actuator that uses pneumatic servo technology for ultraprecise positioning. Our past studies have showed that the minimum resolution of PSBA was almost 6 nm, even under open loop control; thus, we concluded that the PSBA was a promising actuator in advanced ultraprecise positioning systems. However, the stroke of the PSBA was comparatively short. To expand the stroke of the actuator, we proposed and developed a new PSBA with multiple thin thrust-bearing pads. The main purpose in this study is to investigate the positioning properties of the new PSBA with multiple thrust bearing pads. The obtained characteristics of the PSBA can be enumerated as follows. (1) The PSBA with multiple bearing pads achieves a longer stroke than the PSBA with a single pad. (2) The difference in the thickness of the bearing pads affects the dynamic characteristics of the actuator. (3) The minimum positioning resolution of the developed PSBA with twenty-nine bearing pads is about 2 – 4 nm with feedback control.

Dynamic cellular actuator arrays and the expanded fingerprint method for dynamic modeling

A key step to understanding and producing natural motion is creating a physical, well understood actuator with a dynamic model resembling biological muscle. This actuator can then serve as the basis for building viable, full-strength, and safe muscles for disabled patients, rehabilitation, human force amplification, telerobotics, and humanoid robotic systems. This paper presents a cell-based flexible actuator modeling methodology and the General Fingerprint Method for systematically and efficiently calculating the actuators’ respective dynamic equations of motion. The cellular actuator arrays combine many flexible ‘cells’ in complex and varied topologies for combined large-scale motion. The cells can have varied internal dynamic models and common actuators such as piezoelectric, SMA, linear motor, and pneumatic technologies can fit the model by adding a flexible element in series with the actuator. The topology of the cellular actuator array lends it many of its properties allowing the final muscle to be catered to particular applications. The General Fingerprint Method allows for fast recalculation for different and/or changing structures and internal dynamics, and provides an intuitive base for future controls work. This paper also presents two physical SMA based cellular actuator arrays which validate the presented theory and give a basis for future development.

Design of Key Parts of a Pneumatic Conveying System Used in a New Small Trenchless Drilling Robot

Through research on Pneumatic Conveying technology and the principle of Laval Jet, we completed the design of key parts of a mud dust conveying system used a new small trenchless drilling robot in municipal road construction.

Research and Development of Microcomputer Control Pneumatic Technology Comprehensive Experiment Equipment

To meet the experimental requirements of university, we develop a new pneumatic circuit using the PLC control directly drive a large number of low power electromagnetic valves that execute components’ (straight cylinder, cycloidal cylinder) action by computer programming control, through the RS - 232 and PLC communication. This pneumatic circuit has integration of machinery and electricity, which has been proved to be a very good experimental instrument.

Integrated Unit Technology for Gas Field Surface Gathering and Transmission

In combination with the author's experiences in design for integrated unit for natural gas field gathering and transmission, this paper describes conventional practices and technical characteristics of integrated unit in the processes of standardization design and modularization establishment and analyzes the initial application of pneumatic control ball valve, wedge-shaped flowmeter and other new technologies for surface facilities in the gas field. As a result, a new design idea is proposed in this paper, i.e., to improve the integration level of surface facilities, to minimize power consumption and maintenance works and to realize unattended work mode.

The treatment of keloids with pneumatic technology: a pilot study

Keloid scars derive from abnormal fibrous wound healing when the mechanisms controlling tissue repair and regeneration malfunction. Previous studies have reported a reduction in hyaluronic acid among fibroblasts cultured from keloid tissue compared with the levels in normal skin. Here, we evaluated the efficacy and safety of subdermal minimal surgery using hyaluronic acid as a novel treatment in keloid scars. To evaluate the clinical efficacy and safety of subdermal minimal surgery technology in the treatment of keloids. Ten Korean patients (Fitzpatrick skin type II-IV) with keloids on the upper arms were enrolled in this study. All patients underwent three sessions of subdermal minimal surgery at three-week intervals. Scar assessments were performed at baseline, before each treatment session, and three months after the final treatment, with three different assessment methods. Specifically, in addition to the Vancouver Scar Scale (VSS), two independent physicians performed global assessment evaluations regarding the final cosmetic results. As a final form of assessment, participant satisfaction was assessed using a four-point scale. All volunteers completed three treatment sessions, and nine of 10 patients were satisfied with the procedure. The average VSS score decreased three months after the final treatment, and global assessment showed clinical improvement of the scars. No adverse events occurred, except transient spot bleeding at entry points and slight post-procedure edema, which resolved within 48 hours. Subdermal minimal surgery technology may help to improve keloids on the upper arm without noticeable adverse effects.

Special Issue on Pneumatics for Innovative Machine Design

Pneumatics has greatly progressed as convenient multifunctional automation technology. One typical application is in compact light-weight highperformance pneumatic actuators. The introduction of control theory has also enabled useful pneumatic servosystems. New actuators include pneumatic artificial rubber muscles, which are small, light-weight, and soft. These are used for applications in the medical, welfare, and nursing fields. This special issue focuses on actuator development in drive-circuit analysis and design. Issues in these areas include pneumatic actuators, pneumatic rubber muscles, pneumatic circuit analysis and design, energy-saving, pneumatic servocontrol, advanced control systems, industrial applications, automation, vehicles, entertainment, medical, welfare and nursing applications, and education. This special 13-article issue is divided into (i) control design and pneumatic cylinder and bellows applications and (ii) the development and applications of soft pneumatic actuators. Some types of soft pneumatic actuators use artificial rubber muscles for welfare and rehabilitation equipment. This special issue should prove useful in understanding state-of-the-art of pneumatic technology applicable to analysis, design, control, and application in innovative machine design. I would like to express my sincere appreciation to all of the authors and reviewers for their invaluable effort.

A Design of Sheet Metal Handing Manipulator Based on PLC

According to the work requirements of a production line of sheet metal handling, using the mechanical design principles and methods, pneumatic technology and PLC control technology for sheet metal handling manipulator research and design, and development a style of automatic handling manipulator meeting the requirements. This article introduced the sheet metal handling manipulator and principles of the basic structure of the hand, pneumatic systems and PLC control system design and analysis. Practice shows that the manipulator has a simple structure, reliable, efficient features, which meet actual production needs.

Control of Testing Device Based on FluidSIM-P

Pneumatic control technology of Test Equipment has been introduced which is used to Test product‘s hardness. The structure and working principle of detector is introduced, its pneumatic loop and PLC control loop have been designed and optimized by way of the software of FluidSIM-P which belongs to FESTO in Germany. Now, the detector has gained good effect on detecting a kind of vehicle parts, the simulation result is similar to Actual Use result in factory, The research and application in this method are help for developing new electromechanical equipment.

Clinical results of skin remodeling using a novel pneumatic technology

A myriad of technologies are available for the treatment of aging skin. These, however, still lack the ability to combine immediate, short-term and long-term aesthetic results with no downtime. Furthermore, the treatment of fine wrinkles on large surfaces remains challenging, as does the treatment of delicate regions, such as the dorsal hand, neck, and chest. The aims of this study were to evaluate the short-term as well as the long-term efficacy and safety of a new skin remodeling device that pneumatically accelerates a jet of hyaluronic acid (HA) solution under high pressure into the dermis. Thirty-four participants at three clinical sites underwent treatments with the Airgent device on the face, neck, chest, and dorsal hands for a total of 69 sites. Safety and efficacy were evaluated in short-term (1-3 months) and long-term follow-up (up to 18 months) by photography, by an independent reviewer and by participant self-evaluation. Histology was assessed before and 4 months after the third treatment. A total of 69 treatment areas were evaluable at 1-3 months follow-up. Photographic analysis demonstrated improvement in skin variables at all body sites treated. Treatment of the face and neck reduced the mean Fitzpatrick-Goldman Wrinkle Classification score by 39.4 and 30.4%, respectively, representing a full wrinkle class improvement. Treatments of the chest demonstrated significant visual improvement. Treatment of the dorsal hands produced good overall improvement (OI), with good improvement of protruding veins. Overall improvement increased with increasing number of treatments. A total of 56 treatment areas were evaluable for long-term follow-up. Treatment of the face and neck reduced the mean Fitzpatrick-Goldman Wrinkle Classification score by 27.6 and 21.2%, respectively. Improvement after treatment of the face represented a full wrinkle class reduction. Treatment of the chest and dorsal hands yielded significant visual improvement. Overall, 80% of subjects were satisfied with the treatment outcome and would recommend the treatment to friends and family. Histological analysis demonstrated increased dermal collagen ΙΙΙ. Pneumatic injection of HA under high pressure provides a safe, well-tolerated and effective method for improving the appearance of wrinkles on the face, neck, chest, and dorsal hands. Improvement can be seen as early as 1 month and as long as 18 months after treatment.

Daniel W. Repperger, Jr. [Obituary

A brief biography of Daniel W. Repperger, Jr. is given highlighting his professional achievements. He significantly advanced the state of the art in the analysis and modeling of human performance in complex flight motion environments, and he led the development of active control stick technology that employs force feedback to mitigate biodynamic forces, G-effects, spasticity, and tremor. Dan applied his considerable expertise to the control of teleoperated systems, pneumatic muscle technology, and strengthenhancing exoskeletons. Throughout his career he extended key theoretical concepts.

AN EXPERIENCE ON THE AUTOMATION OF PLANT CUTTING TECHNIQUE FOR PROPAGATING PLANTS

Plant cutting is a technique for propagating plants in which a piece of the source plant, called the cutting, is placed in the soil to grow as an indipendent plant. The cutting produces new roots and stems, and thus becomes a new plant. This technique is used in workshops to reproduce plants for selling. In this paper we are presenting a system to automate the plant cutting process of ornamental plants. The process starts with a single stem of the parent plant, with no branches. The system is able to cut the stem for producing the cutting, to remove the leaves from its basal part, and to manipulate it for the hormone subministration and for the insertion in the substrate. The design and the prototype of the automation machine, based on the pneumatic technology, is presented in this paper.

Dense-Phase Pneumatic Conveying Technology for Highly Explosive Metal Powders

This article summarizes a research and development project that was undertaken to develop, design, and implement new pneumatic conveying technology for the safe and reliable handling of highly explosive metal powders. Some of the challenging process requirements and safety design principles that had to be adopted for this project also are described. Using an inert carrier gas, the fluidized dense-phase mode of transport was selected for the processed powders, and external-bypass conveying technology had to be developed for the coarser atomized powders. Operating conditions were optimized to maximize solids loading and minimize gas consumption for the full range of metal powders. With the successful implementation of the new technology, the implications of increased safety design also are discussed.

Auto-laydown robot for space solar module

SUMMARYThis paper discusses about auto-laydown robot (ALR), which is applied to performing the laydown process of a solar module on earth. The robot consists of an adhesive dispensing mechanism, an auto-laydown mechanism, a pneumatic system and a control system. The method of gripping solar cells is described based on pneumatic technology. Meanwhile, a new method of controlling adhesive thickness and area during dispensing is proposed in this paper. The robot realizes the automatic laydown process of solar modules and can control the laydown pressure effectively. Compared with the manual method, the robot could control the dispensing volume and the adhesive area between solar modules and panel substrates, by means of experiments. The novel ALR greatly improves the laydown quality of solar modules and meets the lightweight trend of solar cells development.

MODELING AND DYNAMIC ANALYSIS OF RECONFIGURABLE ROBOTIC GRIPPER SYSTEM FOR HANDLING FABRIC MATERIALS IN GARMENT INDUSTRIES

A reconfigurable robotic gripper based on pneumatic technology has been designed and developed for grasping fabric materials in garment industries automation. The design is based on reconfigurable multidegree of freedom, which can manipulate single and multiple panels of limp materials. The design consist of four arms initially in a cross bar configuration, hosting four suction cups mounted on each of the arms. The design assures low inertia, high modularity and full flexibility adapting to the picking of limp materials in garment and shoe industries. The simulation referring to a worst-case operative cycle has been performed in the environment of a current industrial layout. The kinematic and dynamic performance of the gripper system is analyzed in ADAMS simulation software and the results are presented. The architecture of the gripper is simple and the choice of pneumatic actuators improves the reliability of the system.

Application of a high-pressure gas semi-active resettable damper to the benchmark smart base-isolated building

SUMMARY We discuss the application of a new class of low-cost and high-reliability semi-active devices for the response mitigation of structures subject to earthquakes. These devices, which manipulate stiffness rather than damping, are evaluated by the smart base-isolated benchmark building. The basic motivation, idealization as a stiffness resetting damper or device, development of control logic that ensures the semiactive property, and initial testing and validation results from recently developed prototypes are discussed. The principle idea allows the use of reliable and inexpensive hydraulic or pneumatic technologies, and leads to a decentralized and easy to implement architecture. The results from the benchmark simulations show performance competitive with well-known semi-active techniques. Copyright # 2005 John Wiley & Sons, Ltd.

Study of Web-based integration of pneumatic manipulator and its vision positioning

Pneumatic driven system is widely used in industrial automation, mainly for relatively simple tasks with open-loop control. Because of the pneumatic system’s compressibility and few stop positions, it was considered hard to control in a precise motion control system. With the help of newly developed pneumatic servo control technology, using servo-pneumatic positioning controller now is just as easy as using electro-servo system. This article discusses Web-based servo-pneumatic manipulator control and object recognition and positioning. The authors built a three-degrees-of-freedom (3 DOF) pneumatic manipulator with a servo-pneumatic closed-loop control system and machine vision system in their lab. Web-based tele-operation was a basic ability in this experimental system. After installing a CCD camera, video capture card, and related software developed by the authors, the robot could recognize the user specified object through the Web page and find its position. The remote user could command the robot to move to the position and to grab the object. The critical issues of Web-based control are to integrate hybrid open-architecture mechatronic system through the Web and develop a software language environment characterized by the script. The authors’ experiment showed that pneumatic devices could serve as accurate position control and be controlled through the Web.

Innovative solution for climbing and cleaning on smooth surfaces

A new generation of cleaning robots for domotic applications based on all -pneumatic technology is on study; the project deals with three main fields: motion, cleaning and drying. Referring to motion, an innovative design using pneumatic cylinders as structural elements is being tested; the implementation of a control made with digital valves permits to reduce costs, decrease setup times and leads to a unit which can be easily reconfigured for various applications. A recently developed series of vacuum cups allows the unit to stick itself on surfaces even if dirty or wet; innovative design and materials were studied to guarantee a firm grip in extreme conditions such as metal or glass covered by lubricating fluids. The structure used for motion system and the solutions for control the unit are shown. The cleaning system is based on pneumatic motor driving of rotating brushes with water injection between them. The drying system is based on fluidic concepts and driven by compressed air; studies about Coanda effect were carried on trying to extract water directly from wet surface without contact. Computational Fluid Dynamic simulations and experimental tests were carried on to validate the models; comparative analysis about performances and fluid consumption are here presented.

Enhanced Modelling and Performance in Braided Pneumatic Muscle Actuators

Pneumatic technology has been successfully applied for over two millennia. Even today, pneumatic cylinder based technology forms the keystone of many manufacturing processes where there is a need for simple, high-speed, low-cost, reliable motion. But when the system requires accurate control of position, velocity or acceleration profiles, these actuators form a far from satisfactory solution. Braided pneumatic muscle actuators (pMAs) form an interesting development of the pneumatic principle offering even higher power/weight performance, operation in a wide range of environments and accurate control of position, motion and force. This technology provides an interesting and potentially very successful alternative actuation source for robots as well as other applications. However, there are difficulties with this approach due to the following.(i)Modeling errors. Models of the force response are still nonoptimal and for good results these models are highly complex, which makes accurate design difficult.(ii)Low bandwidth—the bandwidth of the actuator—link assemblies are often considered to be too low for practical success in many applications, particularly robotics.In this paper we address these limitations and show how the performance in each area can be enhanced with overall improvements in the response and utility of the braided pMAs.