Applied Mechanics and Materials Vols. 128-129

Abstract: Aiming at the flow and pressure pulsation caused by the reciprocating pump in aircraft deicing system, two solutions are presented in the paper. First, based on computational fluid dynamics and finite element analysis theory, the assembled ways of rigid and flexible accumulators are applied to absorb vibration in order to inhibit the pulse. Then, the control algorithm for multiple phases of three pumps is used to offset the pulse energy among the pumps. At last, simulation results show that both methods have effectively reduced the pulsation in the aircraft deicing system.

Abstract: An optimal solution of multi-objective optimization has been proposed for the measure project of automatic test system (ATS) because of the formation complexity and the factors diversity. The method is used to select the optimal measure project for ATS. First a quasi-ideal solution is defined using maximum subjection principle from fuzzy theory. Then calculate the subjection of the existing projects and get their maximum subjection under specific weight set. Finally the optimal measure project has been obtained. The signal integrity, data throughput, cost, degree of automation, volume scale and expansion capabilities are regarded as integrated key factors according to bus forms and system architecture. The optimal measure project of ATS is determined by finding maximum subjection. Therefore the selection method enhances the cost-effectiveness of ATS formation.

Abstract: Synchronization onto arbitrary orbit for diffusively coupled complex networks is of great application value and was investigated in this paper especially when nodes are chaotic systems. A decentralized nonlinear PID controller was proposed for this purpose. The controller was designed with assistance of associated feedback system of the network. A particle swarm style self-optimization algorithm was provided to find the optimal parameter of the controller online with IAE performance index. Finally a networked Chen system was given to be controlled to track sine wave, square wave and triangular wave simultaneously as the example to verify the method presented.

Abstract: Semi-physical acoustic vision simulation system of autonomous underwater vehicle (AUV) was established by combining physical simulation of decision layer with virtual simulation of sensory and executive layer. The hardware and software architecture of the simulation system were explained in detail. The virtual simulation of sonar sensor and the design of sonar vision processing system of the physical simulation were described. Finally, the long distance obstacle avoidance simulation, special objects search simulation and multi-objects tracking simulation tests were conducted to demonstrate the importance of the system to the success of sea experiments.

Abstract: The twiste angle has a great effect on shaping law and stability of Numerical Controlled Electrochemical Machining (NC-ECM) process. In order to avoid the disadvantages caused by twiste angle, a methode of study shaping law by dispersing cathode working face in NC-ECM was proposed, and a mathematical model of the shaping law with the effects of twiste angle has been established in this paper. The mathematical model disclosed the relationship of twiste angle β, feeding velocity v_f and thickness of removal material h in NC-ECM. Theoretical and experimental results show the the mathematical model of shaping law described in this paper can be considered as a useful reference and is helpful for the analysis of the NC-ECM and general ECM process.

Abstract: Orthogonal experiment was used to optimize the design of spherical cymbal transducer. Through variance analysis of orthogonal experiment results, the primary and secondary order that each design factor affects the frequency performance of spherical cymbal transducer has been found. At the same time, the significant level of each design factor has been gained. Those factors which have highly significant or significant effects on the frequency performance of spherical cymbal transducer should be considered carefully during design spherical cymbal transducer, and those factors which have no significant effects can be ignored. In this way, the design factors were reduced, and the design complexity of spherical cymbal transducer was simplified.

Abstract: Memory test technology is the most effective means to record the parameters of moving objects under special circumstances. This paper introduced the development of storage test systems based on ARM7LPC21XX. PHILIPS chip 16/32-bit microcontroller-LPC21XX was a 16/32-bit ARM7 TDMI-S CPU microcontroller based on a real-time emulation and embedded trace. It had two powers-saving modes-power down and idles, which could ensure the battery to work for a long time. The microcontroller internal 10-bit AD was used to sample data as well as SPI and NRF24L01 modules to realize communication.

Abstract: A new control method used in the semi-active suspension is studied. The force generated by the semi-active damper can be divided into two parts, one is the uncontrollable force, and the other is the controllable force. In order to make the sprung mass have the ideal isolation effect, the controllable force should be equal to the sum of the uncontrollable force and the force generated by the suspension spring. But the controllable force is limited by many constraints. Therefore, the control strategy can be concluded. The simulation results show that the ride comfort and handling stability are both improved by the control method.

Abstract: Based on the research of dynamic characteristics of axial flow blood pump which is drove by the large gap magnetic drive system, a serial communication between PC and AT89C51 to realize the real-time process of the blood pump acceleration is proposed. The acceleration control parameters are decided by the analysis of blood pump speed control mechanism. As a result, Previous, the previous program which is modified to change the control parameters repeatedly is saluted by building the PC model. At the same time, the control of multiple control parameters could be achieved when a program on the microcontroller is addressed. What’s more, the more experiments will be realized, to provide more conveniences to the system.

Abstract: Based on the circuit topology of the grid-side converter, the control model of the grid-side converter is established, control technique of dynamic hysteresis for active inverter is analyzed, meanwhile, the relationship among feedback currents, the inductance, the maximum given current and the minimum given current, the difference value between DC bus voltage and network voltage is derived. The experimental system with DSP core is developed. Theory analysis and simulation results show that the control technique is feasible, which has some practical values.