Applied Mechanics and Materials Vols. 373-375

Abstract: It will cause the drop of the acceleration performance and driving comfort if the continuously variable transmission shift too quickly. So Aiming at the shifting problem of continuously variable transmission system, This thesis put forward the method to control shift speed of the continuously variable transmission based on driving intention. By the dynamics analysis of continuously variable transmission system, it does a research on the influence on the motor automobiles acceleration performance and driving comfort, when the ratio changes too fast. According to working practice, analyzing shift way of continuously variable transmission system. Through the above analysis and findings, the method to control shift speed based on driving intention will be designed to make acceleration and driving comfort unified. And by limiting the maximum CVT ratio change rate, the automobile acceleration performance can be further improved.

Abstract: This paper deals with modeling and adaptive fuzzy control of winding hybrid-driven cable parallel manipulator (WHDCPM). The WHDCPM has the advantages of both the traditional cable-parallel manipulator (CPM) and hybrid-driven based cable-parallel manipulator (HDCPM) since the hybrid-driven planar five-bar mechanism in HDCPM is replaced by winding hybrid-driven five-bar manipulator in WHDCPM. The physical architecture of WHDCPM is determined, and kinematics and dynamics of the cable parallel manipulators have been studied based on Lagrange method. The numerical simulation is demonstrated as an example with adaptive fuzzy control theory, and the diagrams of trajectory tracking, cable tension, friction compensation and motor torque are shown, respectively. The results demonstrate the feasibility and superiority of the WHDCPM.

Abstract: Flexible and reliable gripping is a fundamental task in various micromanipulation and microassembly fields. Shape-controllable menisci based on pressure adjustment were proposed to pick up microobjects. Lifting force is provided by a controllable liquid bridge which is formed between the capillary tube and the microobject. The volume and the shape of the meniscus could be regulated dynamically by changing the pressure at the capillary nozzle orifice, thus the capillary force alters correspondingly. The pressure adjustment was realized by adjusting the height of the reservoir device precisely. Fluent software was used to simulate the fluid meniscus under different pressures. Experiments were performed to achieve controllable meniscus with different height difference of liquid level between the reservoir device and the capillary nozzle orifice, and microobjects griping operations were executed to verify the method.

Abstract: Based on the application drawback of the conventional motor reciprocating within certain angle, a novel permanent magnet arc guideway motor (PMAGM) is put forward which directly converts electrical current into limited angular moment, producing torque through a limited rotation angle of normally much less than ±180°. According to the permanent magnet (PM) magnetization and solenoid coil electrifying modes, five different magnetization orientations and three different electrifying modes are analysed. Results show that electromagnetic force of Y direction magnetized alone the external field force lines is larger than any other magnetization orientations, 40% higher than that of vertical magnetization. X direction electromagnetic force magnetized alone the external field force lines in proposal 3 is 2.5 times that of the vertical magnetization in proposal 2. The electromagnetic force and dynamic response performance of designed PMAGM could be improved effectively and provided with certain practical significance.

Abstract: This paper aims at proposing a structured approach in reliability design and analysis for mechatronic devices. Mechatronic systems are a complex integration of extremely advanced technological components able to perform tasks with high accuracy and flexibility. This complexity at all levels increases the risks of malfunction, failures and issues. The definition of an effective roadmap is necessary to provide prompt solutions in terms of product performances and duration. This study presents a set of reliability activities to be integrated in the product process development and during its cycle life. This approach may contribute to improve the mechatronic product functionalities and duration.

Abstract: In this paper, a motion control system based on 2-axis gimbal system is designed and implemented to drive a high speed and precision. The proposed system consists of the RS-422 interface, 2-axis gimbal platform, SCU (servo control unit) integrated with a high speed DSP chipset, SAU (servo amplifier unit), potentiometer sensor unit, and resolver sensor unit. The SCU using the DSP firmware is designed to get a fast response without an overshoot with step input and a RMS error of low probability with ramp input. The SAU using a voltage control is designed to resolve the zero-crossing distortion for precise motion. To verify the performance and stability of the implemented system, experiments are performed through a measurement of the time and frequency domain response in a laboratory environment by using a PXI (PCI extentions for instrumentation).

Abstract: The loader's steer-by-wire system combines the automatic control system and hydraulic system. The system cancels the mechanical or hydraulic connection between the steering wheel and the front wheels, which existed in the original steering system, optimizing the adaptation of the loaders steering systems road feeling to its working conditions, convenient for the integration with other systems, and harmonization of control. This paper puts forward a new measurement of a steer-by-wire system steering angel. It aims at more accurate corner detection, will design to optimize loader's steer-by-wire hydraulic system signal detection, and better meet the actual needs.

Abstract: The degree of compaction is a measure of the main evaluation index of road machinery compaction quality, but also affects the working characteristics of vibratory roller. In order to make the vibratory compaction always be in the best working state, we must adjust the operating parameters of the roller based on the real-time compaction pressure degree of the compacted material,for the best compaction effect. The paper analyzes the vibration frequency, amplitude, speed and other main working parameters and the relationship between degree of compaction,discusses how to select the main parameters, and carries out the research of Road Machinery Intelligent compaction system.

Abstract: Aim. The full paper begins with a variety of Electro-Hydraulic Pump (EHP) and a review on work of existing hydraulic pump, resulting in, in our opinion, the conclusion that it is absolutely essential to in-depth study on the EHP, a highly integration of electric motor and hydraulic pump. We now present a model how to get temperature field of our design plunger EHP that we believe that it can much better develop the EHP. In the full paper, we explain our method in some detail; in this abstract, we just add some pertinent remarks to naming the topics, such as motor thermal model, the fluid model and the heat conduction model. We discuss the temperature distribution under the different leakage decided by oil film thickness. Finally we do simulations in ANSYS. The simulation results in the full paper show our method for the temperature field is efficient to design the EHP.

Abstract: Properly controlling electro hydraulic power steering system can improve steering performance. The relation of motor speed, vehicle speed and steering speed is gained, according to the influence of motor speed on the steering performance. The force and angle input is set in the driver input model. Rotary valve is simulated by four orifices. The steering resistance between tire and ground is simulated by the coulomb friction on two tips of the rack. The method of double closed-loops PID is used to control the motor. The influence of the control strategy on the steering performance is realized by the simulations of three typical situation, which includes steering portability, road feel, the speed of assist force response and its stability. The results of simulation validate the availability of the control strategy, which is the basic of optimization.