Advanced Materials Research Vols. 308-310

Abstract: A testing system is constructed by connecting two parallel mechanisms in series to assess the performance of the 6-DOF parallel stabilized platform. In addition, a conception, the kinematic isolation factor, is proposed to describe the capability of the parallel stabilized platform and is combined with the kinematic influence coefficient method to form the first and second order influence coefficient matrixes as well as the velocity and acceleration expressions. The definition of the kinematic isolation factor simplifies the establishment of the kinematic equations, and the acceleration formula especially appears a concise format. These kinematic equations are solved according to a certain turbulence signal of a moving carrier, and the results indicate that the kinematic isolation factor describes the parallel stabilized platform’s capability that it correctly compensates the motion of the carrier and evince that the testing system effectively evaluates the performance of the parallel stabilized platform.

Abstract: The paper presents a method to design a LQG controller for dynamic positioning system. It is assumed that these are corrupted with white noise hence a Kalman filter is applied to observe the ship motion exposed to environment disturbances like wind, wave & currents, The simulation results show that the performance of the filter and controller are suitable, and the method is practicable .

Abstract: Active materials are a group of solid-state materials whose geometric shape can be related to an energy input in the form of heat, light, electric field, or magnetic field. In the application of active materials to electromechanical energy conversion, electrical energy may be input to the material and the resulting deformation of the material can be used to move a load. The most common active materials used in actuators are piezoelectrics, magnetostrictives, and SMAs. In this paper, a piezoelectric actuation concept is presented that uses a new feed-screw motion accumulation technique. The feed-screw concept involves accumulating high frequency actuation strokes of a piezoelectric stack (driving element) by intermittently rotating nuts on an output feed-screw. The main parts of piezoelectric actuation such as clamp mechanism, rotary mechanism and “L type” driving mechanism are investigated. From the analysis, the deformation and stress of it are all under allowed value of 65Mn. The mathematics model of upside of rotary mechanism rotation motion is established. The results indicate that, the mechanisms of actuator all are satisfy the need of design

Abstract: Based on screw theory,a systematic method is proposed to synthesis symmertrical non-overconstrained 3-DOF translational parallel manipulators(TPMs).Firstly,the configuration conditions of non-overconstrained TPMs are analysis.The generation of symmertrical non-overconstrained TPMs is reduced to design the structure of serial chains with one infinite pitch wrench,and to combine the same serial chains inparallel.Finally,making sure that, the union of the wrench for the same serial chains in each combination constitutes a three infinite pitch wrench system.we get all the 3-legged symmertrical non-overconstrained TPMs.

Abstract: Humanoid robot is a highly nonlinear system and balance control is essential to achieve the purpose of stable walking on the plane. As for the inclined plane, the stable walking is even much more difficult. This article proposes a walking pattern with off-line planning for Humanoid robot walking on slopes, which combines the cart-table model on an inclined plane to realize stable walking. The control algorithm is implemented on our robot, experimental results show the realization of stable walking.

Abstract: This paper analyzes the spinning characteristics of a noncontact spinning mechanism with numerical simulation. In this mechanism, when the suspended object is stably levitated in the vertical direction by a magnetic suspension system, the disk magnets spin the suspended object in the horizontal direction by means of the remanent magnetization on the surface of the suspended object. The disk magnets are arranged around the levitated object, and the magnetic poles are arranged in a parallel configuration. In this paper, the mechanism is introduced, and the remanent magnetization on the surface of the suspended object is examined using a gauss meter. A numerical model is set up, and the spinning characteristics are analyzed with a step input and its velocity in steady states conditions using different numbers of magnets.

Abstract: Abstract: For biped robot, to control the moving stability is the key technology for the design. The biped robot has a human figure and several pose when moving. It is difficult to control its dynamic stability using the traditional method. This article gives a dynamic energy pyramid method, derives the characteristic parameter ----overturning stability index that maintain stable, and gives the method to calculate the overturning stability index. According to the overturning stability index, using the fuzzy neural network adaptive control system can change the configuration and velocity of the robot real time to assure its overturning stability. It will be easier to control the stable movement of the robot using the parameter. The action generated by the system has good practicability and high reliability, also can reduce the danger in the movement of the robot.

Abstract: This paper describes the basic structure and driving principle of the closed Planetary Bevel-type CVT, and the characteristics of minus differential gear-train is applied to combine DISCO CVT with the differential gear-train. Several major structural forms combined the DISCO CVT are listed, and analyze its movement, power flow and calculate its efficiency. The feasibility and superiority of this idea is proved.

Abstract: Choose wheat straw, corn straw and thatch as the shock isolation layer materials, the static state function and the dynamic state mechanics function experiment have been made to them. This article also analysis the influence of anti-vibration ability by elastic modulus and water saturation rate under the same layer thickness.

Abstract: The lanthanum-silver doped hydroxyapatite (La/Ag/HAP) powder was prepared by a coprecipitation way. Its microstructure, phase composition and thermostability were investigated by means of X-Ray diffraction, scanning electron microscopy, and Fourier Transform Infrared. The antibacterial properties against E.coli and S.Aureus were detected using a minimum inhibitory concentration method. The biocompatibility was confirmed by cell culture of osteoblasts of rat cranium. Results show that the investigated La/Ag/HAP powder exhibited the features of typical HAP phase in the experimental temperature, and its shape was needle-like with a diameter of 50~80 nm and a length of 300~500 nm. It is of a good biocompatibility and is more stable at high temperature, and is also a stronger antibacterial agent than pure HAP powders.