Narrow Results

When wood materials are used for a mechanical structure, the fatigue strength should be estimated due to repeated loads they receive. This paper reveals that the methods to calculate allowable stresses along with American Society for Testing and Materials (ASTM) and Architectural Institute of Japan (AIJ) can take the strength reduction due to fatigue into account because the ASTM/AIJ allowable stresses against the static strength closely resemble the fatigue limit against the wood static strength.

Design of the hollow modular joint plays an important role in modern robot layout, fixation, and wiring. In this paper, a hollow modular joint that meets the requirement of a minimally invasive surgical robot is proposed. The mechanical and control design is sequentially illustrated, and the torque sensor and its optimization are provided. Furthermore, a free-force control method is introduced. To analyze the designed module, the simulation of the redundant robot, comprised of the designed joint in seven degrees of freedom, is presented. The results of analyses showed that the designed hollow modular joint is valid and effective.

The European Spallation Source (ESS), which is established as a European Research Infrastructure Consortium (ERIC), is a multi-disciplinary research facility that is currently under construction. ESS has as vision to develop to a world class facility, enabling scientific breakthroughs in research related to materials, energy, health and the environment. The ESS facility is built by a collaboration of some 100 research institutes and universities.

With its 5 MW average beam power, its linac will be the most powerful linac of all neutron spallation sources. Neutrons are obtained by delivering 2 GeV protons at a repetition rate of 14 Hz to the He-cooled solid tungsten rotating target. The Accelerator is built with a high percentage of In-Kind Contributions (IKC) with major accelerator systems being designed, prototyped and built outside ESS. The first major accelerator elements are now being assembled and tested with their first parts being installed. Future similar large-scale projects could likely be IKC-based, which is a powerful model. Within ESS, the Mechanical Engineering & Technology (MET) section is responsible for developing and maintaining mechanical engineering and design throughout the facility. The mechanical design is consolidated in the master model and available under the ESS Plant Layout, including all In-Kind Contributions as well as other related mechanical engineering content. Consequently, the MET section is also responsible for the design, development and supervision of the proton accelerator and tungsten target in terms of civil and infrastructure design for the physical plant. In parallel, ESS has set stringent goals for high availability and reliability on the machines during operations. In order to deliver these goals and monitor the aging status of critical parts of the machines, prototypes and one-of-a-kinds, the MET section has developed and currently implements Structural Health Monitoring (SHM) program on the accelerator primarily and other machines for Operations. The innovative strategy and application of Non-Destructive Testing for Machines (NDTM) is under development by the MET section with the leading benefit of utilizing the technology of Resonant Ultrasound Spectroscopy (RUS). Both reference and irradiated samples undergo RUS measurements to obtain spectral responses of the dedicated materials, for machine reliability and operations availability purposes.

Retinal surgery can be performed only by surgeons possessing advanced surgical skills because of the small, confined intraocular space, and the restricted free motion of the instruments in contact with the sclera. Snake-like robots may be essential for use in retinal surgery to overcome this problem. Such robots can approach the target site from suitable directions and operate on delicate tissues during retinal vein cannulation, epiretinal membrane peeling, and so on. We propose an improved integrated robotic intraocular snake (I²RIS), which is a new version of our previous IRIS. This study focused on the analyses of the kinematics and drive mechanism of the dexterous distal unit. This unit consists of small elements with reduced contact stress achieved by changing wire-hole positions. The kinematic analysis of the dexterous distal unit shows that it is possible to control the bending angle and direction of the unit by using two pairs of drive wires. The proposed drive mechanism includes a new pull-and-release wire mechanism in which the drive pulley is mounted at a right angle relative to the actuation direction (also, relative to the conventional direction). Analysis of the drive mechanism shows that compared to the previous drive mechanism, the proposed mechanism is simpler and easier to assemble and yields higher accuracy and resolution. Furthermore, considering clinical use, the instrument of the I²RIS is detachable from the motor unit easily for cleaning, sterilization, and attachment of various surgical tools. Analyses of the kinematics and drive mechanism and the basic functions of the proposed mechanism were verified experimentally on actual-size prototypes of the instrument and motor units.

The design of spray robot control system introduced a kind of servo motor and other intelligent technologies based on PLC and touch screen. To complete the spraying operation, the function and implementation of the control system required to be based on the geographical environment of the field, crop growth, the situation of crop diseases and insect pests, and other characteristics. This system supports the relatively advanced PC, mobile phone, wireless remote control to make the control simpler and convenient. The experimental results show that the control system can meet the requirement of spraying job based on intelligent spray robot for better achievement of the required desired results, so that the control system has a wide range of practical value and application prospect.

When automatic glass glue machine works, two questions of the machine starting vibrating and stick-slip motion are existing. These problems should be solved. According to these questions, a glue machine's model for studying stick-slip is established. Based on the dynamics system describing of the model, mathematical expression is presented. The creep critical speed expression is constructed referring to existing research achievement and a new conclusion is found. The influencing factors of stiffness, dampness, mass, velocity, difference of static and kinetic coefficient of friction are analyzed through Matlab simulation. Research shows that reasonable choice of influence parameters can improve the creep phenomenon. These all supply the theory evidence for improving the machine's motion stability.

When wood materials are used for a mechanical structure, the fatigue strength should be estimated due to repeated loads they receive. This paper reveals that the methods to calculate allowable stresses along with American Society for Testing and Materials (ASTM) and Architectural Institute of Japan (AIJ) can take the strength reduction due to fatigue into account because the ASTM/AIJ allowable stresses against the static strength closely resemble the fatigue limit against the wood static strength.