This study proposes an experimental method for the performance evaluation of a commercial combined probing system equipped with a contacting probe, an imaging probe, and a line laser scanner developed by our cooperation. According to its application purpose, this method first obtains the circular characteristics of our novel designed 3D artefact composed of 2D rings, cone and cylinders. It is suitable to measure the touch probe, imaging probe as well as optical sensor. Next, detailed measuring procedures were defined for this artifact, in order to achieve comparable results and make the measurements feasible for the different sensors involved. A series of representative experiments were carried out on a commercial combined probing system produced by our partner. The experimental results show that multiple probing system form error and location error were less than 4.0μm, and multiple probing system size error was less than 2.0μm in three different registration positions. System combination errors were less than its maximum permissible errors (MPEs). On the other hand, its root mean errors (RMSE) were less than 0.5μm. Therefore, we can conclude that the designed artifact is suitable to be used to assess the performance of CMMs with multiple probing systems. These conclusions are helpful for further use of this combined probing system and can be utilized to optimize those combined parameters further.
The characteristics of turbidity in the watershed of Chongqing City’s water supply system in interconnected reservoir basins between JiaLingJiang River and Chang Jiang River are investigated and analyzed by dynamic light scattering method (DLS). Three months of continuous turbidity measurements in seven sampling sites along the JiaLingJiang River were respectively performed from March to May in 2018. The experiment results demonstrated that the particles with highly similar light-scattering features are the main contribution to turbidity in the JiaLingJiang River. The analysis of turbidity time series showed that the particle populations from water sources impacts in downstream waters and the influence of urban wastewater pollution and wet weather pollutant was not obvious in those months. On the other hand, the relative errors of turbidity measurement results were always less than 3% with national turbidity standard.