Abstract: In this paper we use queuing theory to analysis the incoming traffic, developed an effective way to control the traffic of a circle by using stop signs and yield signs,and calculated the traffic capacity and average waiting time of this method. Then, we use signals to control the traffic and improve the original method by a analysis the ways the car can pass through the circle crossing. Taking into account of the traffic flow in the different time of a day, we got the light's signal period to adapt to the features of the traffic flow.
Abstract: This paper studies three degrees of freedom used in multi-joint robot kinematics in the process of loading and unloading problems, through the homogeneous coordinate transformation method to describe the spatial relationship between two adjacent connecting rod, thus derived the equivalent homogeneous transformation matrix between "gripper coordinate system" and "reference frame", establishing a movement equation for the operation arm, then worked out all joints variable with the known position vector of the last connecting rod.
Abstract: High renewable energy penetration in power systems may bring a series of problems such as frequency fluctuations. Plug-in electric vehicles (PEVs) and controllable loads have been shifting into focus for this. A dynamic vehicle-to-grid (V2G) model with feedback control is proposed by considering the battery charging/discharging characteristics and the dynamic model of frequency regulation with PEVs and controllable loads for a single area is established. Simulation results demonstrate that the application of PEVs and controllable loads can relief the frequency refutation due to the randomness of renewable energy sources.
Abstract: While tracking the periodic input signal, the position-dependent periodic thrust ripple caused by ending effect, load disturbance and the friction of the permanent magnet linear synchronous motor (PMLSM) will reduce the servo performance of the system. Especially when the periods of the reference input signal and thrust fluctuation interference signal are not synchronous, the precision of periodic signal tracked by the servo system is reduced, which lead to the reduction of the servo system’s periodic signal tracking precision. Therefore, a multi-period discrete repetitive controller using two improved prototype repetitive controllers which are incomplete parallel to restrain\track the multi-period input signal was designed. Theoretical analysis and simulation results show that the proposed scheme can improve the precision of the system tracking periodic signals and restrain the periodic thrust fluctuations effectively.
Abstract: Based on the mathematical model of the brushless DC motor (BLDCM), a self-adaptive fuzzy PID controller is designed to achieve high-precision speed control of motor by adopting fuzzy control principle, simulation is conducted in MATLAB /SIMULINK, the result shows that the controller can work well with quick response, no overshoot output and high control precision, has strong robustness under the circumstances of various disturbances and parameter variations, whose static and dynamic performance with the self-adaptive fuzzy PID control are both better than conventional PID control.
Abstract: Terminal sliding mode control (TSMC) was designed with introduction nonlinear function into sliding hyper-plane, which makes tracing error converge to zero in finite time. The standard TSMC (STSMC) control and non-singular TSMC (NTSMC) control was designed for an uncertain two-order nonlinear dynamic system, the sliding function and controller of STSMC control and NTSMC control are designed respectively, also the finite time of arrival was analyze. The stability was proved with Lyapunov theory, the performance comparison of STSMC and NTSMC was simulated with conclusions that STSMC control and NTSMC control are all feasible control for nonlinear system, STSMC control exist singular problem, but NTSMC control without singular problem, with sliding surface and control law with different parameters, the control characteristic can realized, which was suitable for special control system.
Abstract: Multi-fingered robot hands have been one of the major research topics because several robotic systems, including service robots, industrial robots and wheel-type mobile robots require grasping and manipulation of a variety of objects as crucial functionalities. Roughly speaking, there are two different types of robotic behavior: free motion, purpose of this paper and constrained motion that would be published in the near future. In this paper, we address the problem of multi-fingered robot hand’s dynamic modeling which is fundamental in design of model-based controllers for grasping and manipulation tasks. Based on the specified multi-fingered robot hand, a new methodology for deriving an efficient dynamic equation by the Lagrange formulation is presented. This methodology is new in the sense that it considers the coupling dynamics of the system in the identification of the parameters of the dynamic equation. Furthermore the developed dynamic model leads to decoupling dynamic characteristics, by which the control of different parts of the system can be separately simulated. So the new structure of the dynamic model was very useful and effective for the simulation and the diagnostic. Several simulation results proved that the derived dynamic model can predict the motion of the multi-fingered hand in free motion.
Abstract: In this article‚ a new approach is presented to determine the various shapes of workspaces of 5 bar symmetric planar parallel manipulators. Here the shape of the workspace is determined by the number of ways the workspaces of the two serial manipulators intersect with each other. Geometric conditions are established in each case and area of each shape of workspace is determined in closed form. Singularity is another important consideration in the design of parallel manipulators. In this paper, an approach is presented to go through the singularity points using an automatic selective actuation mechanism. A prototype 5-bar planar manipulator is fabricated along with an automatic selective actuation mechanism demonstrating the manipulator going through the singularity points.
Abstract: A new technology of pellet production-drying-chloridizing roasting is proposed for valuable metal recovery from pyrite cinder with high content of lead and zinc. The pyrite cinder, containing 60.15% Fe, 2.02% Pb and 2.15% Zn, was pelletized with addition of 2% bentonite in pan pelletizer. Green balls after drying were roasting at 1100 °C for 60 min with 5 wt % of CaCl2 addition in tube furnace. The results demonstrate that pellets with 61.58% of TFe, lead and zinc volatile ratios of 98.02% and 96.83% were obtained. Key technique is that CaCl2 reacts with lead and zinc compounds and the chloride can be volatilized at moderate temperatures. This new technology can recover the valuable metal fully from pyrite cinder and produce qualified concentrate as iron-bearing feed for steel industry, which will help to solve the pollution of pyrite cinder and extend raw material sourcing for Chinese steel industry.
Abstract: A novel method is described to synthesize carbon nanotubes (CNTs) –thin graphite layer hybrid materials by a one-step catalytic chemical vapor deposition of acetylene on porous copper bulk. In porous copper, graphite thin layer grows uniformly on the surface of the pores while CNTs sprout out to form a network. As observed by scanning and transmission electron microscopy, the obtained CNTs exhibit bamboo-like multiple-walled structures.