[9] applied a vision system to automatically http://www.selleckchem.com/products/Perifosine.html detect the surface cracks in welds. Shafeek et al. [11] developed an expert vision system to inspect different weld defects during the gas pipeline welding. Among different types of vision systems for inspection purpose, the vision systems based on principle of laser triangulation attract much attention both from academia and industry. Laser triangulation method was initially developed for distance measurement in a one-dimensional space. Based on the function of distance measurement, laser triangulation sensors are also developed for other applications such as a novel pulse measurement Inhibitors,Modulators,Libraries system developed by Wu et al. [12].

By extending laser triangulation sensor into two-dimensional space, it also can be applied as 3D imaging and reconstruction sensors in different Inhibitors,Modulators,Libraries areas such as automotive [13], culture heritage, medicine, criminal investigation [14] and integration with robot for the purpose of measurement [15] and manufacturing industry.Table 1.Different types of Inhibitors,Modulators,Libraries weld defects.Based on reported data, the feasibility of using vision system to inspect weld quality has already been studied. However, most of the vision systems themselves are usually complex systems consisting of expensive and bulky hardware and software. The cost of the vision system, the practical implementation difficulty of the vision system into industrial environment, and the image processing efficiency always bring up some challenges that greatly limit their applications. As shown in Table 2, the costs and Inhibitors,Modulators,Libraries features of different systems are compared.

It can be observed that most of the systems cost much more than 10,000 dollars while only one laser scanner from NextEngine is lower than 10,000 dollar. However, it can be noted that this relatively GSK-3 cheap system is not developed for real-time industrial application. For example, the USB cable used by this system only has a maximum length of 0.5 m and the low scan speed and small amount of image data that can be processed per second are not suitable for industrial application with requirements on the hardware and real-time processing.Table 2.Costs and features of different laser range sensors.In order to solve these issues, a low-cost laser-based vision system is developed in this study to achieve the weld quality inspection efficiently.

In order to satisfy the demand for weld quality inspection in industrial environment, a Gigabit Ethernet (GigE) industrial camera is adopted selleck chem to overcome the disadvantages of the commercially available cameras. The GigE camera can transfer images at a high speed up to 196 frames per second with a cable length up to 100 m. These features of the GigE industrial camera well accommodate the requirements for the high speed welding of large structures in a hostile industrial environment and for the post-weld quality inspection.