Advanced Materials Research Vols. 1049-1050

Abstract: Nature works hard to destroy bearings, but their chances of survival can be improved by following a few simple guidelines. Extreme neglect in a bearing leads to overheating and possibly seizure or, at worst, an explosion. But even a failed bearing leaves clues as to what went wrong. After a little detective work, action can be taken to avoid a repeat performance.

Abstract: The relatively simple control strategy can decrease the complexity of the ultrasonic motor system and increase the cost performance. The nonlinear iterative learning control algorithm is simple, the control parameters can be determined according to little experimental knowledge. According to the control characteristics of ultrasonic motor, the nonlinear iterative learning control algorithm is improved and the nonlinear iterative learning control strategy of motor’s speed is designed. Experiments show that the motor system has good iterative learning capacity, the control effect is improved generally in the repeated learning process and the control strategy is simple and effective.

Abstract: Aiming at a kind of special object with fractional characteristics,a new kind of fractional order PI^λ-PD^μ controller is put forward in this paper,In this control system, the forward channel of system contains a fractional order PI^λ controller,while the feedback loop adopts PD^μ controller.The control structure in this fractional order system can achieve a good performance of the closed loop control.Moreover,the impacts on system dynamic performance and static performance are compared when the parameters in the controller are changed.The results show that when these parameters are in the reasonable range,the system can achieve better control performance.

Abstract: With the development of mathematical theory of fractional order, fractional order control system is more widely studied and discussed. In order to make the theory system of fractional order control systems perfect,this paper give out the review of fractional order control systems.The fractional order controller is divided into five categories to be described.

Abstract: Profiling roll forming machine based on the theory of cold roll forming is a new equipment for sheet forming. A dynamic optimal design process for this machine can improve the operational reliability and dynamic response characters of its mechanical systems. Dynamic intelligent optimization method which is developing is very suitable to settle the problems of dynamic optimization for mechanical systems, and its application fields should be vigorously promoted. On account of the Particle Swarm Optimization has the advantages of easy understanding, easy realization and strong capability of global search, this paper decides to adopt the Particle Swarm Optimization combined with dynamic design. The method applied to mechanical systems of profiling roll forming machine is successful to optimize some relative parameters and improve the dynamic performance of the system.

Abstract: The electric boiler as object controlloed has the characteristics of nonlinear, time-varying and large lag, and the temperature control system of it has been a challenge. In order to improve the control performance, a novel temperature control system was designed. The system consists of temperature controller, temperature acquisition, temperature display, serial communication, and warning circuit. The core controller was relized by DSP 2407, which can execute advanced control algorithm. A hybird control algorithm was presented, which mergeed PID and fuzzy control. Simulation experiment of PID and presented algorithms were carried on respectively, and the simulation results showed that the system designed has good dynamic and still performance. Furthermore, the system is simple and has a certain application value.

Abstract: The dynamic positioning (DP) vessel maintains its position and heading by active thrusters. For safety reasons, DP vessels are typically designed with redundancy thrusters more than needed for motion control. Optimization theories are useful in finding thrust allocation solutions that minimize fuel consumption and reduce “wear and tear” on a thruster. But several challenges exist such as uncertain thruster model, thruster dynamics characters and the individual limitations of the thrusters. In this paper, a dynamic thrust allocation scheme is presented based on model predictive control (MPC) that directly takes thrusters with dynamics characters and various constraints into account. It is shown in simulations that the MPC dynamic thrust allocation scheme performs better in comparison with an existing static allocation method. Its main advantage is the ability to handle thruster dynamics characters and various constraints.

Abstract: This paper realized the design of the controller is controlled byan IC card refueling and settlement, just the controller can be installed on an existing tanker achieve control, while refuelingrecords and some configuration information can be stored in the local memory .For the transformation of gas station, don’t need to replace the expensive refueling machine, only need to add an IC card controller based on the existing filling machine, thereby greatly reducing the cost of upgrading the gas station, but also laying the foundation of the next step of information upgrade for gas station.

Abstract: In this paper, the maintenance manipulator of charged robot is discussed as the main research object. It analyzes the characteristics of the main structure and movement form of the charged robot maintenance manipulator. The analysis of working process and control requirements is made for manipulator. A control system which uses the Siemens S7-200 as the core, is designed to achieve the remote operation and control of manipulator. This article discusses the components of the system and how the electronic control system achievesthe control of each joint with PLC controller as the core.

Abstract: Based on the matching relationship between curve I of ideal braking force distribution and curve β of brake’s braking force distribution, the effect of hydraulic retarder on braking stability of coach is analysed, and the ideal braking force distribution strategy between hydraulic retarder and friction brake is put forward. The coordination control strategy of braking force between hydraulic retarder and friction brake is analyzed, and the dynamic coordination control strategy based on double closed-loop control structure and the coordination control algorithm with Anti-lock brake system (ABS) based on state machine are put forward. According to the above-mentioned coordination control strategy between hydraulic retarder and friction brake, the braking torque of hydraulic retarder can be made full use of and the degree of wear and heat load of friction brake can be greatly reduced in the premise of ensuring braking safety and comfort.