Dynamic Control Method and Application of Highway Toll Station Lanes

Parallel manipulators with less than six degrees of freedom (DOF) have been increasingly used in high-speed hybrid machine tools. The structural features of parallel manipulators are dynamic, a characteristic that is particularly significant when these manipulators are used in high-speed machine tools. However, normal kinematic control method cannot satisfy the requirements of the control system. Many researchers use model-based dynamic control methods, such as the dynamic feedforward control method. However, these methods are rarely used in hybrid machine tools because of the complex dynamic model of the parallel manipulator. In order to study the dynamic control method of parallel manipulators, the dynamic feedforward control method is used in the dynamic control system of a 3-PSP (prismatic-spherical-prismatic) 3-DOF spatial parallel manipulator used as a spindle head in a high-speed hybrid machine tool. Using kinematic analysis as basis and the Newton-Euler method, we derive the dynamic model of the parallel manipulator. Furthermore, a model-based dynamic feedforward control system consisting of both kinematic control and dynamic control subsystems is established. The dynamic control subsystem consists of two modules. One is used to eliminate the influence of the dynamic characteristics of high-speed movement, and the other is used to eliminate the dynamic disturbances in the milling process. Finally, the simulation model of the dynamic feedforward control system of the 3-PSP parallel manipulator is constructed in Matlab/Simulink. The simulations of the control system eliminating the influence of the dynamic characteristics and dynamic disturbances are conducted. A comparative study between the simulations and the normal kinematic control method is also presented.The simulations prove that the dynamic feedforward control method effectively eliminates the influence of the dynamic disturbances and dynamic characteristics of the parallel manipulator on high-speed machine tools, and significantly improves the trajectory accuracy. This is the first attempt to introduce the dynamic feedfordward control method into the 3-PSP spatial parallel manipulator whose dynamic model is complex and provides a study basis for the real-time dynamic control of the high-speed hybrid machine tools.

Zhang, D. and Liu, X., 2020. Dynamic control method and application of coastal engineering project construction cost based on rough sets. In: Bai, X. and Zhou, H. (eds.), Advances in Water Resources, Environmental Protection, and Sustainable Development. Journal of Coastal Research, Special Issue No. 115, pp. 7-9. Coconut Creek (Florida), ISSN 0749-0208.The traditional cost analysis method of construction engineering has low operation efficiency and poor convergence performance, which leads to inaccurate cost analysis. With the increasingly fierce competition in the construction market, construction enterprises must strengthen the control and management of project costs in terms of systems and measures in order to continuously find profit space in low-cost and low-profit projects. Due to the complexity of the construction process and the uncertainty of many influencing factors, it is difficult to formulate a scientific cost control strategy, predict the degree of influence of various cost factors and reveal the correlation between them and the total cost before construction. Construction cost management of engineering project is the most concerned topic in coastal engineering project, and also the basis and key point of cost control of coastal engineering project. In order to judge the importance of cost factors and find the relationship between cost factors in coastal engineering projects so as to realize scientific cost control decision-making, it is necessary to objectively judge the main influencing factors of cost based on as many cost data as possible.

This paper presents dynamic control and a dead-time compensation method of an isolated dual-active-bridge (DAB) dc-dc converter. Conventional phase-shift control methods for the DAB converter may cause dc offsets in both inductor current and transformer magnetic flux density in transient states. The dynamic control method in this paper independently controls the diagonal switches in each H-bridge converter to modify the duty ratios in transient states. This method enables both inductor current and transformer magnetic flux density to be settled within a half switching period without any dc offsets. Moreover, the phase-shift error caused by the dead time is analyzed in terms of the switching angle. This analysis reveals that the dead time causes the switching-angle error in only one of the two H-bridge converters and may cause dc offsets. A new dead-time compensation method based on this analysis is proposed to eliminate the dc offsets and to achieve a good dynamic response. A 5-kW experimental system verifies the validity of the proposed control method.

To prevent bus bunching, a dynamic headway control method in the V2I (vehicle to infrastructure) environment for a high‐frequency route with bus lane is developed. Bus operating speed guidance on the mid‐blocks and intersection signal adjustment are two main strategies in the proposed method. A forecasting model of bus travel time under the dynamic control method is developed. The objective function is set up by taking into account differences between actual bus headways and dispatching headways, and the scaling ratios of intersection cycle lengths. The optimization model is solved using genetic algorithm. The proposed method is applied to a real bus route in Meihekou city, China, and compared with the current control plan as well as holding strategy. Results show that the proposed method can reduce bus headway deviations in all investigating periods; negative impacts on cars can be limited by setting reasonable values for the parameters.

t is important to reasonably raise the reservoir flood limited water level in order to increase the utilization of the rainwater resources. The methods to set the flood limited water level include the static control and the dynamic control. And the dynamic control methods include the multiple duration method and the dynamic control method. All those methods were summarized and analyzed in this paper, especially the dynamic control. The advantages of the multiple duration method and the dynamic control method for the flood were indicated respectively. Those two methods were contrastively analyzed from the design principles, the application conditions, the actual operation complexity and the risk control factors. Then the conclusion was obtained, that the dynamic control method will be more advantageous and popular than the multiple duration the in the future.

Due to the popularity of wireless local area networks (WLANs), many research works for such networks have been done, mainly based on the assumption that the number of nodes, N, is known a priori and remains the same in the runtime. However, in the real world, N changes dynamically because wireless stations can be turned on/off or moved in/out anytime and anywhere. As a consequence, the theoretical results based on the assumption usually have their own limitations when considered with industrial applications in a WLAN. For this problem, we introduce in this paper a dynamic transmission control method to take into account the dynamic of WLANs. Based on the so-called p-persistent IEEE 802.11, the dynamic method can adaptively adjust the transmission probability in each back-off stage of DCF to achieve the maximum performance in the runtime. We use analysis to show how the method can achieve the maximal performance in theory. With simulations, we further confirm these results and show how the parameters involved can be settled to achieve the performance aims.

A new dynamic control method is discussed for robot arms. It is based on nonlinear feedback and diffeomorphic (state) transformation which externally (or exactly) linearizes the whole system and provides simultaneous output decoupling. The non-linear feedback is augmented with optimal error correcting controller, which operates on the task error level. Several computer simulations were performed to evaluate the performance of the new dynamic control method. The simulation results are discussed in detail. The simulations show that the new dynamic control method provides very good tracking performance even in cases when the dynamic model parameters of the robot arm are only known with 10-30% error. The functional characteristics of the nonlinear feedback law and optimal error correcting controller are discussed briefly.

Dynamic error prediction and link strain feedback control for a novel heavy load multi-DOF envelope forming machine

By combining theoretical analysis and practical test, this paper present an dynamic dimming control method of highway tunnel LED lighting based on controllability of LED light, and undertook a comprehensive analysis of dynamic control method and Principle. And developed a highway tunnel LED lighting dynamic dimming control system. Through the demonstration analysis on tunnel LED lighting system of demonstration project, it indicated that the research results can significantly save the lighting electricity cost of highway tunnel lighting system under safety, on-demand lighting conditions. Which will provide a energy saving dynamic dimming control scheme for highway tunnel LED lighting system in our country.

In the cloud environment, owing to the large-scale sharing of the upper application instance and the underlying virtual machine resources, the tenants' information flow boundary in the shared virtual machine is fuzzy and difficult to identify. In addition, protection of tenant information flow between processes is inadequate, resulting in the leakage of sensitive information of tenants. Therefore, a dynamic control method for tenants' sensitive information flow based on virtual boundary recognition is proposed. By analyzing the behavior and operation log of tenants, the behavior feature vectors of tenants are constructed, and an automatic recognition algorithm of tenant virtual boundary based on the dynamic spiking neural network is designed. This algorithm can realize dynamic identification of the tenant virtual security boundary when the application service demand changes dynamically. Further, combined with the concept of centralized and decentralized information flow control, a dynamic control method of sensitive information flow is established. The security label is formally defined by using the lattice structure, and the control rules of tenants' information flow and the rules of tenant label encryption-declassification are designed. Thus, the independent, dynamic and secure control of tenants' information flow inside and outside the tenant virtual boundary. Finally, the detailed design of a dynamic security control application system for cloud tenants' sensitive information flow is provided. Experiments confirm that the proposed algorithm can identify the security boundary of tenants more accurately and efficiently than the traditional spiking neural network classification methods. Further, the security and effectiveness of the method is verified by the intransitive noninterference theory and the experiment of information flow control.

By employing the fuzzy control theory and dynamic matrix control method, the controllers for temperature control of a room cooled by a displacement ventilation system are developed. The fluid flow and heat transfer inside the room are calculated by solving the Reynolds-averaged Navier–Stokes equations, including the effects of buoyancy in conjunction with a two-equation realizable k–ε turbulence model. Thus, the physical environment is represented by a nonlinear system of partial differential equations. The system also has a large time delay because of the slowness of the heat exchange. Additionally, the temperature of the exterior wall of the room first increases and then decreases with time during a 24-h period, which acts as a strong disturbance in changing the temperature of the room. The goal of this article is to develop controllers that will maintain the temperature in the room within the specified upper and lower bounds by deploying the displacement ventilation system. In order to solve this temperature control problem, we develop a special fuzzy control method. At the same time, we analyze the peak value of the error and employ the dynamic matrix control method to replace the fuzzy control method with success. The results show that the fuzzy controller is effective in saving energy, and the dynamic matrix control method can contain the error within the specified bounds in the worst situation (when the temperature of the exterior wall is highest). These kinds of fuzzy control and dynamic matrix control methods can also be employed for other heating, ventilating, and air-conditioning systems such as overhead variable air volume system and radiant cooling hydronic system.

The highly integrated valve-controlled cylinder (HIVC) is the joint driver in the hydraulic drive legged robot motion process, with the inner-loop-control-based outer loop dynamic compliance control method of the hydraulic system adopted. Yet the dynamic compliance of the HIVC position inner loop control has effects on the accuracy of the outer loop dynamic compliance control. Therefore, the dynamic compliance parallel composition theory of the HIVC position inner loop control is presented and its dynamic compliance is analyzed in this paper, based on the HIVC position control nonlinear mathematical model. Moreover, the multiple parallel branch dynamic compliance compound compensation control method is also designed and the dynamic compliance parallel composition is rearranged. The experimental results indicate that adopting the compensation control method can decrease the dynamic compliance of the HIVC position control system dramatically, which would provide the inner loop dynamic compliance compensation control method of the robot with high accuracy and high robustness.

This paper proposes a global tracking control method for underactuated ships with input and velocity constraints using the dynamic surface control (DSC) method, where the control structure is formed in a modular way that cascaded kinematic and dynamic linearizations can be achieved similarly as in the backstepping method. First, the first step linearization of the kinematics determines the pseudo (or auxiliary) surge velocity and yaw angle, which are used as the commands for the second-step linearization. Then, in the second-step linearization of dynamics, the actual torque inputs are designed to make the actual surge velocity and yaw angle follow these pseudo commands to achieve the position and yaw angle tracking. By employing the dynamic surface control method in the design of each kinematic and dynamic linearization law, we can obtain a control structure that is much simpler than the previous backstepping-based controllers such that it is beneficial from the practical application viewpoint. In addition, it is possible to track general reference trajectories, i.e., the reference yaw velocity need not be persistently exciting and there is no restriction on the initial yaw tracking error. In particular, global tracking control is achieved even in the presence of input and velocity constraints, unlike the DSC method which introduces the several filters in the backstepping design procedure to avoid the model differentiation and make it easier to be implemented and usually has semiglobal tracking performance. Finally, the stability analysis and numerical simulations are performed to confirm the effectiveness of the proposed scheme.

This paper proposes a dynamic synthetic inertia control method, considering the fatigue loads of the wind turbine. The control objectives include reducing the rate of change of frequency and frequency nadir of the power system and the fatigue load of the shaft and tower of the wind turbine. A frequency regulation model of the power system containing the primary operating dynamics of the wind turbine is established. The dynamic synthetic inertia control method is proposed according to the relationship between fatigue load, wind velocity, and frequency. Case studies are conducted with a wind turbine fatigue load under a synthetic inertia control with different weights for different wind velocities and system loads. Therefore, the dynamic weights are obtained. Comparing the rate of change of frequency and frequency nadir and equivalent damage load, the efficacy of the proposed method is verified.

Robust Robot Arm Control with Nonlinear Feedback