T-spline based unifying registration procedure for free-form surface workpieces in intelligent CMM

With the development of the modern manufacturing industry, the free-form surface is widely used in various fields, and the automatic detection of a free-form surface is an important function of future intelligent three-coordinate measuring machines (CMMs). To improve the intelligence of CMMs, a new visual system is designed based on the characteristics of CMMs. A unified model of the free-form surface is proposed based on T-splines. A discretization method of the T-spline surface formula model is proposed. Under this discretization, the position and orientation of the workpiece would be recognized by point cloud registration. A high accuracy evaluation method is proposed between the measured point cloud and the T-spline surface formula. The experimental results demonstrate that the proposed method has the potential to realize the automatic detection of different free-form surfaces and improve the intelligence of CMMs

Measuring information integration model for CAD/CMM

A CAD/CMM workpiece modeling system based on IGES file is proposed. The modeling system is implemented by using a method of labelling the tolerance items of 3D workpiece. The concept-feature face is used in the method. Firstly the CAD data of workpiece are extracted and recognized automatically. Then a workpiece model is generated, which is the integration of pure 3D geometry form with its corresponding inspection items. The principle of workpiece modeling is also presented. At last, the experiment results are shown and correctness of the model is certified

Investigation of the horizontal collision damage behavior of fruit during transporting based on a new instrumented impactor

Horizontal collisions between fruit and rigid walls are a common occurrence in postharvest packaging and transportation. To address this issue, a novel high-precision instrumented impactor was developed, comprising a high-speed imaging system, an ejection device, and a force sensor. Results showed that the impactor was able to effectively simulate the horizontal collision process between various small spherical fruits (such as cherry tomatoes, plums, sweet cherries, and winter jujubes) and packaging materials at three velocities: slow, medium, and high. Output parameters included the impact force and impact time of the fruit acting on each packaging material, as well as the displacement, displacement rate, impact energy, rebound energy, and absorption energy of the fruit. During the horizontal collision simulation, it was observed that the winter jujube exhibited the largest impact force and the shortest impact time among the four types of fruit tested. Conversely, the sweet cherry demonstrated the lowest proportion of damage area when colliding with the EPE board compared to the rigid board and foam board. This study presents a powerful tool for investigating the horizontal collision behaviour between fruit and rigid plates

AMY coordinated observations, reanalysis and data management

Proceedings of GRENE 3rd Workshop (17-19 March, 2014, Bali, Indonesia