• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.44 no.1
• /
• pp.64-69
• /
• 2007

This paper designs an interpolator for a high speed ultra wide bandwidth (UWB). The UWB wireless technology will play a key role in short-range wireless connectivity supporting very high bit rates availability, low power consumption, and location capabilities. Because the UWB needs high operating speed, a cubic interpolator based on variable parameters for the UWB needs to be operated at a high speed. In order to improve an operating speed, the modified cubic interpolator is based on both a parallel processing and a pipelining in the existing interpolator simultaneously. Experimental results show that a maximum operating speed and period of the proposed interpolator using Stratix II EP2S60F1020C3 is 102.42MHz and 9.764ns, respectively. Compared to the conventional interpolator, the designed cubic parameter interpolator has been improved more than about 190%.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.10a
• /
• pp.51-54
• /
• 2002

This paper deals with an implementation of NUBS interpolator and presents the process of its integration into PC-NC. For more accurate feed, NURBS algorithm is improved. Also, Evaluation of real time NURBS interpolator is provided to verify fred accuracy and geometrical accuracy of NURBS curve. NURBS machining of fee surface is simulated on the real time NC simulator so that machining time is compared to that of linear path machining.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.33 no.2
• /
• pp.62-69
• /
• 1984

In this paper we present a microprocessor-based interpolator using algebraic arithmetic method. The interpolator consists of 2900 "bit-slice" microprocessor chips and 0.5K ROMs of 36-bit microprogram memory. The system design is an instuction-data-based architecture with 250ns cycle time. A significant feature of the interpolator is that it has flexibility, very fast interpolation speed of 250 K pulses/sec, and performs additional functions simultaneously. Throughout the paper detailed explanations are given as to how one can design the hardware and software, and experimental results are presented.presented.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.43 no.6 s.312
• /
• pp.71-82
• /
• 2006

For real-time animation, keyframe animation that consists of translation, rotation, scaling transform nodes is used widely in 3D graphics. This paper presents geometrical watermarking using vertex coordinates in CoordIndex node and interpolator watermarking using keyvalues in PositionInterpolator node for 3D keyframe animation based on VRML. Experimental results verify that the proposed algorithm has the robustness against geometrical attacks and timeline attacks as well as the invisibility.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2004.04a
• /
• pp.323-328
• /
• 2004

Finish machining of a curved surface is often carried out by an NC system with curved interpolation in a high speed machining strategies. This study aims to develop the NURBS interpolator for the PC-NC based machine tools. In the case of a finish cut using a ball-end mill in high speed machining, low machinability at the bottom of a tool produces a harmful effect on surface roughness. The developed interpolator considers the relation between inclined angle, surface roughness, and feed rate, and adjusts real-time feed rate in order to generate surfaces which have isotropic surface roughness. The proposed interpolator is fully implemented and an experimental results are shown.

• Journal of the Korean Society for Precision Engineering
• /
• v.21 no.12
• /
• pp.60-66
• /
• 2004

Increasing demands on precision machining of 3D free-form surface have necessitated the tool to move smoothly with varying feedrate. To this regard, parametric interpolators such as NURBS (Non-Uniform Rational B-Spline) interpolator have been introduced in CNC machining system. Such interpolators reduce the data burden in NC code, increase data transfer rate into NC controller, and finally give smooth motion while machining. In this research, a new concept to control cutting load in NURBS Interpolator was tried based on the curvature of curve. This is to protect cutting tool, and to have good machinability. For proof of the system, cutting force and surface topography were evaluated. From the experimental results. the interpolator is good enough for machining a free-form surface.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2001.04a
• /
• pp.492-495
• /
• 2001

In order to utilize a parallel machine tool for CAM system, the development of adequate interpolator is necessary. This paper presents a quintic B-spline interpolator with algorithm of limiting maximum interpolation error. The favored property of near arc-length parametrization in the curve representation is used in the implementation of the reference command generation. Then, this interpolator is applied to cubic parallel manipulator to show its validity.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2000.05a
• /
• pp.1032-1035
• /
• 2000

Increasing demands on precision machining with computerized numerical control (CNC) machines have necessitated that the tool to move not only position error as small as possible, but also with smoothly varying feedrates in space. This paper presents a new high precision interpolation algorithm for 3-dimensional (3D) Non-Uniform Rational B-Spline (NURBS) curve in the reference-pulse CNC technique. Based on the minimum path error strategy, real-time NURBS interpolator was developed in software and this was implemented with a PC-NC milling machine. The several experimental results have shown that the proposed NURBS interpolator is useful for the high precision machining of complex shapes. It is expected that this algorithm can be applied to the CNC machines for the machining of 3D free-form surfaces.

• Journal of Korea Multimedia Society
• /
• v.10 no.1
• /
• pp.36-48
• /
• 2007

This paper proposed 3D keyframe animation using orientation interpolator. 3D keyframe animation consists of a number of transform nodes that have geometrical node of initial model and several interpolator nodes that represent the object moving. In the proposed algorithm, we randomly selects transform nodes with orientation interpolator node and performs to resample quaternion components for haying uniform key time. And then, watermark bits are embedded into quaternion components with large rotation angles. Experimental results verified that the watermark embedded by the proposed algorithm had good robustness against geometrical attacks and timeline attacks and also PSNR of keyvalue in orientation interpolator node is above 42dB.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.3C
• /
• pp.287-296
• /
• 2007

3D keyframe animation is used widely in 3D graphics for real-time animation. This is a method that registers the animated key values in the important several frames among the entire frames and generates the rest frame by interpolator using the registered key values. This paper proposed the watermarking for 3D keyframe animation using PositionInterpolator. The proposed algorithm selects randomly the embedding meshes, which are transform nodes among the entire hierarchical structure. Then the watermark is embedded into keyValues of PositionInterpolator in selected transform node. Experimental results verified that the proposed algorithm has the robustness against geometrical attacks and timeline attacks.