• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.1
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• pp.8-15
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• 2003

The cylindrical object such as a water pipe or an oil pipeline are widely used in the infrastructure. Those pipes should be inspected periodically by human or a robot. However, since there is no edge or vertex in the pipe, it is very difficult for the robot to navigate along the pipe. In this paper in order to guide the robot along the axis of the pipe, an algorithm which find the axis using the measured range data from the robot to the pipe wall is developed The algorithm is verified using both the simulated range data and the measured one.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.12
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• pp.38-44
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• 1995

This paper presents a method to measure the position and orientation of a Cylindrical Object(unknown the eiameter and length) lying on a floor, using a camera. The two extreme cross section of the cylinder will be viewed as distorted ellipese or circular are, while its limb edge will be shown as two straight lines. The diameter of the cylinder is determined from the geometric properties of the two straight lines, which in turn provides information regarding the length of the cylinder. From the 3-dimensional measurement, the 3D coordinates of the center points of the two extreme cross sections are determined to give the position and orientation of the cylinder. This method is used for automated pick-and-place operations of cylinder, such as sheet coils, or drums in warehouses.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.211-212
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• 2012

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.24-27
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• 2003

This paper discusses practical strategies for transition from a pinching to a power grasping, where a multi-fingered hand mounted on a robotic arm envelops a cylindrical object on a table. When the manipulation system grasps a cylindrical object like a pen on a desk, a complete enveloping is not impossible in the initial configuration. The system firstly pinches the object only with two or three fingers and then grasp it with fingers and a palm after regrasping. In this pinching-grasping transition maneuver, human unconsciously selects proper strategy according to some conditions including object dimensions and initial pinching positions. In this paper we therefore develop six possible strategies for this pinching-grasping transition and then investigate their performances for some objects with various dimensions and various grasping positions, using numerical simulations. Based on their results, effective strategies are implemented by using a hand-arm system.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.7
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• pp.167-174
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• 1998

This paper presents an unoccluded cylindrical object pose measurement using a slit beam laser in which a robot recognizes all of the unoccluded objects from the top of jumbled objects, and picks them up one by one. The elliptical equation parameters of a projected curve edge on a slice are calculated using LSM. The coefficients of standard elliptical equation are compared with these parameters to estimate the object pose. The hamming distances between the estimated coordinates and the calculated ones are extracted as measures to evaluate a local constraint and a smoothing surface curvature. The edges between slices are linked using error function based on the edge types and the hamming distances. The linked edges on slices are compared with the model object's length to recognize the unoccluded object. This proposed method may provide a solution to the automation of part handling in manufacturing environments such as punch press operation or part assembly.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.1017-1018
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• 2010

• International Journal of Naval Architecture and Ocean Engineering
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• v.12 no.1
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• pp.733-742
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• 2020

Taking the cylindrical float of the floating fence of a floating litter collection device as the research object, based on the shallow immersion characteristics of the cylindrical float, the Morison equation is modified, and the interaction between regular waves and the partially immersed horizontal cylindrical float is discussed in combination with scale model test. The results show that the modified Morison equation can accurately predict the wave force of the horizontal cylindrical float and reveal the influence of amplitude, immersion depth and period on the wave force of the cylindrical float. For partially immersed cylindrical floats, the wave force increases with the increase in wave height and decays with the increase in period. The positive value distribution of the wave force is larger than that of the negative direction, and the difference between the positive and negative directions is mainly affected by the immersion depth.

• Korean Journal of Optics and Photonics
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• v.16 no.3
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• pp.177-181
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• 2005

Although there are many ways to measure the diameter of a cylindrical object, in this study, the diameter of a cylindrical objects were measured by the geometric optical method and interference-diffraction method which are two kinds of tipical non-contact methods. In geometric optical method, the curved laser beam is formed on the cylindrical surface by spreading the inclined laser beam using the cylindrical lens. The curve is captured by CCD camera and the diameter is calculated by geometry. And the interference and diffraction patterns of investigated cylindrical objects are analyzed in interference-diffraction method. In this study, the cylindrical objects, whose diameters are $0.05\;mm\;\~\;100.50\;mm$ were measured by the geometric optical method and interference-diffraction method. The results show that in each method, the relative errors of the measurement are within $2\%$ and $1\%$, respectively and these non-contact methods can be applied in the quick measurement of many objects.

• IEMEK Journal of Embedded Systems and Applications
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• v.18 no.3
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• pp.117-124
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• 2023

In the machine vision inspection equipment, diameter measurement is important process in inspection of cylindrical object. However, machine vision inspection equipment requires complex algorithm processing such as camera distortion correction and perspective distortion correction, and the increase in processing time and cost required for precise diameter measurement. In this paper, we proposed the algorithm for diameter measurement of cylindrical object using the laser displacement sensor. In order to fit circle for given four input outer points, grid search algorithms using root-mean-square error and mean-absolute error are applied and compared. To solve the limitations of the grid search algorithm, we finally apply the singular-value-decomposition based circle fitting algorithm. In order to compare the performance of the algorithms, we generated the pseudo data of the outer points of the cylindrical object and applied each algorithm. As a result of the experiment, the grid search using root-mean-square error confirmed stable measurement results, but it was confirmed that real-time processing was difficult as the execution time was 10.8059 second. The execution time of mean-absolute error algorithm was greatly improved as 0.3639 second, but there was no weight according to the distance, so the result of algorithm is abnormal. On the other hand, the singular-value-decomposition method was not affected by the grid and could not only obtain precise detection results, but also confirmed a very good execution time of 0.6 millisecond.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.703-704
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• 2010