Study on the dynamic characteristics of a virtual-axis hybrid polishing machine tool by flexible multibody dynamics

Advances in Mechanical Engineering

2013

The assurance of software reliability of the CNC system is difficult to realize with the continuous increase in the computational complexity and software scale of the CNC system. Therefore, there is an increasing demand for efficient methods that are able to locate the defect codes quickly and accurately. This study proposes a practical fault location method which is based on the similar path set and artificial neural network (ANN). The detailed fault location process involves the following steps: (1) according to the execution information recorded by the monitor, the failed path is generated; (2) the similar path set is obtained from the control flow graph and the failed path; the ANN is trained by the learning sample which is composed of the failed path and the similar path set; (3) the defect code is judged by ANN. The results of the fault location experiment on the interpolation module showed that the proposed method located the software fault quickly and accurately without depending on the experience and intuition of maintainers.

Section: Analysis Of Fault Location Of Cnc Softwarementioning

confidence: 99%

Software Fault Location of CNC System Based on Similar Path Set and Artificial Neural Network

Yuan

Advances in Mechanical Engineering

2013

“…Meanwhile, it can compensate the shortcoming of the small workspace of the parallel mechanism. Yu et al (2004) studied the dynamic characteristics of the hybrid machine tool by means of the theory of dynamics of flexible multi-body systems. The stable status of polishing can be obtained at all periods of the movement of the machine except the beginning of the movement.…”

Section: Structure Of Machine Tool and Experimentsmentioning

confidence: 99%

Process optimization of the serial-parallel hybrid polishing machine tool based on artificial neural network and genetic algorithm

Zhao

et al. 2010

J Intell Manuf

A kind of serial-parallel hybrid polishing machine tool based on the elastic polishing theory is developed and applied to finish mould surface with using bound abrasives. It mainly consists of parallel mechanism of three dimensional moving platform, serial rotational mechanism of two degrees of freedom and the elastic polishing tool system. The active compliant control and passive conformity of polishing tool are provided by a pneumatic servo system and a spring, respectively. Considering the contradiction between the machining quality and efficiency, the optimization model of process parameters is found according to different machining requirements, namely single objective optimization and multi-objective optimization, which provide a choice of parameters as a basis for the operators in practice. Many polishing experiments are conducted to collect the data samples. The genetic algorithm integrated with artificial neural network is used for researching for the optimal process parameters in term of the various optimization objectives. This research also lays the foundation for further establishing polishing expert system.

“…Many automatic mold polishing systems have been developed in past years, which are mostly based on conventional machine tool structure (Guo et al, 2013;Suzuki et al, 2010), the industrial robot (Fusaomi et al, 2007;Robin et al, 2011), and other structures (Liao et al, 2008;Yu et al, 2004) such as series-parallel hybrid structure (Li, 2002;Sun et al, 2004). Although numerical control (NC) machining technology can control polishing tool movement well, NC programming is more complicated.…”

Section: Introductionmentioning

confidence: 99%

“…Typically there is the conflict of workspace, precision and rigidity for traditional articulated robots polishing systems. To essentially reduce the shortcomings of a serial system mentioned previously, Yu et al (2004) and Wang et al (2012) developed a kind of serial-parallel hybrid polishing system, but it could not be used to polish a large mold surface due to the workspace. Up to now, polishing equipment used to finish a large mold free-form surface, such as a large automobile panel mold surfaces, are relatively scarce in the literature.…”

Section: Introductionmentioning

confidence: 99%

Development and Polishing Process of a Mobile Robot Finishing Large Mold Surface

Machining Science and Technology

Zhang

Zhao

et al. 2014

2 A novel self-determination polishing robot finishing large mold free-form surface is developed, and the finishing process method is researched. Contrary to traditional approaches, our premise is that a large mold surface can be polished by using a small robot. This robot system is mainly composed of a polishing robot part, a computer system and a visual positioning system. A type of robot with four uniform distribution wheels was designed, which has two driving wheels and two driven wheels. Active compliant control of the polishing tool was provided by a pneumatic servo system, and a new special compliant abrasive tool was proposed on the basis of robot characteristics. The process planning steps consisted of subdividing the free-form surface, choosing an abrasive tool, planning the polishing path and optimizing machining parameters. Based on the orthogonal experiment and the grey relational analysis method, the optimal parameter combination was obtained for polishing force, tool speed and feed rate. Aiming to polishing times, the surface roughness method and polishing efficiency method were studied in detail. The polishing experiments were carried out in the robot using process parameters obtained by the efficiency method. These research results provided significant theory foundation and experimental data for a mobile robot planning polishing to realize intelligible process parameter selection.