Advanced Materials Research Vols. 291-294

Abstract: During the liver intervention surgery, the excellent doctor with the help of CT image need puncture the patient several times to find the correct tumor position. Thus, the pain increases for the patient. For the problem a low-cost auxiliary robot system with the help of virtual reality technology for liver invasion surgery is introduced. The auxiliary arm can indicate the punctuation path for doctor and the virtual reality system can find the difference between the planning path of simulation and actual indication path of robot. Then the error can be compensated by modifying and updating the simulation model. Thus the system based on virtual reality is more accuracy and more effective.

Abstract: To study the amount changes of different denitrifying bacteria in the process of the metal membrane bioreactor, and to confirm the relationship between the amount of different bacteria and the quality of the treating water, the fluorescence in situ hybridization (FISH) dominant molecular biological technologies were applied in this study to preliminary explore the time and space distribution of different denitrifying bacteria populations in the active sludge on the immersed plate-type metal membrane bioreactor. The result indicates that the involvement of the denitrification tank is beneficial to the growth of all bacteria and nitrifying bacteria, meanwhile the eliminate rate of the total nitrogen and ammonia nitrogen is also improved.

Abstract: Wireless sensors network has been widely used in a real-time monitor, percept or gather physical information such as light, temperature, humidity, noise or Concentration of harmful gas. With its simple and efficient characteristics, Ant colony algorithm has been widely used in WSN rout. An energy efficient rout algorithm based on ant was shown in this article, in which an energy-related descending parameter was used. The improved algorithm avoids excessive repetition use in the network link, in order to use the network energy effectively, and at the same time transmission rate is also guaranteed.

Abstract: The space relationships among flange coordinate, camera coordinate and calibration reference coordinate are analyzed. A simple calibration method for the relationship of the eye-in-hand of robot vision is proposed and corresponding experiment system is designed. The result of experiments shows that this method can work simple and shortcut with higher precision.

Abstract: Nowadays Wireless Sensor Networks (WSN) has been widely used because of its adaptability, mobility and scalability. The MAC protocol is one of the most important network protocols which guarantee the WSN communication efficiency. The major concern of this paper is the typical contention-based MAC protocol in WSN—the S-MAC protocol. Considering the backoff algorithm of S-MAC protocol cannot resolve the fairness problem for nodes communication, the BDQR (Backoff Depends on Queue and Retry) backoff algorithm was presented in this paper. The experimental results demonstrated that by using this algorithm, nodes communication fairness was improved, channel collisions were reduced while network lifespan was prolonged.

Abstract: To solve the difficulty in processing the weld image of multi-threshold and small size using the traditional image processing algorithms, image preprocessing has been optimized combining with the traditional mode of image processing. The maximum distance location algorithm and the line grey location algorithm have been designed on the basis of lines position combining with the specific characteristics of the weld image. These two algorithms are applied to process the weld image of multi-threshold and small size. Finally the wrong values of the weld images are removed according to the Pauta rule, thus achieving a linear correction of the edge. This paper introduces the basic ideas and the implementation methods of the two positioning algorithms in details. The experimental results show that the two algorithms can effectively resistant the interferences of noise, have a high precision positioning, and retain edge images with better detail characteristics.

Abstract: Based on the study of a patent, the configuration and action principle of a new variable displacement of double-action vane pump is discussed. The pump is equipped with floating blocks that may move up and down in accordance with the rotational speed of the pump. The pump belongs to an automotive hydraulic power steering system. The mathematical and simulation model for the hydraulic power steering of an automobile was established. Different pump parameters were selected for simulation. The simulation results showed that the pump with the floating block can provide power characteristics are better than a common pump. The utilization of the proposed pump is expected to improve efficiency and decrease exhaust gas and noise.

Abstract: A kind of relative rotational speed measurement system based on magnetic signal and spectrum correction should be proposed for the most of current methods of relative rotational speed measurement cannot meet the measurement requirement of small size, high overload resistance in the military and industrial fields. The system collects the fixed length of time asymmetric periodic intensity signal of magnetic induction based on the characteristics of magnetoresistive sensor’s non-contact measurement, and then analyze the signal spectrum by FFT in order to obtain the accurate main frequency components in the frequency domain after the spectrum correction. The system can determine the direction of the relative rotation by detecting the waveform in the time-domain.

Abstract: This paper takes the layered water injection technology in oil production engineering as research object. This technology is characterized by strong nonlinearity, strong interlayer interference, time variation and complex model. Focusing on these characteristics, this paper proposes a novel control strategy based on PID-NN algorithm to satisfy the requirements of layered water injection technology. Many performance indexes of the controller are optimized, including model establishment of nonlinear controlled object, multi-parameter decoupling, controller acceleration and precision improvement. The simulation and experiment show that compared with traditional controller based on PID and controller based on BP neural network, the optimized controller has stronger robustness, faster response and better flow control, so it has an advantage over traditional controllers of dealing with discrete events and multi-variable decoupling problems.

Abstract: 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.