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In this paper, several approaches are applied for 3D reconstruction of range gated imaging with the objective to improve the 3D performance in terms of accuracy and resolution. Feasibility of the proposed image processing, 3D reconstruction model, super-resolution technique, and mesh refinement is demonstrated. Our test case shows that the depth error of 3D reconstruction is improved from 2.26% to 1.65% after mesh refinement. This gives a constructive idea to provide optimised 3D solution and benefit various applications. The proposed approaches and the findings presented may stimulate further interest in the relevant fields such as machine vision and 3D active imaging.

Despite the advances made in laser and sensor technology, setting up an accurate range gated imaging system remains a challenge. In this paper, we emphasise on the importance of system setup and its impacts to the performance of three-dimensional (3D) range gated reconstruction. Study is performed to analyse some of the system setup criteria and parameters involved in the laser and camera synchronisation, images acquisition and reconstruction, and illumination setup. It is hoped that the presented findings establish better understanding of the setup influences in range gated reconstruction and contribute to optimise the system performance.

The objective of this work is to demonstrate an experimental methodology based on structural intensity technique to visualize energy flow in hard disk drives with a scanning laser Doppler vibrometer. Preliminary experimental results illustrate the feasibility of the proposed methodology to locate sources/sinks and chart energy flow paths in a hard disk drive.

Track access time is an important parameter for high performance hard disk drives (HDDs). Presently, the resonances of the head actuator assembly (HAA) caused by the pivot stiffness and mass of the HAA are becoming an even more urgent problem, since these resonances have become the main design factor which limits further reduction of track access time and improvement of the servo control bandwidth in HDDs. This paper investigates the influence of the driving pulse waveforms on residual vibrations and attempts to identify a seeking pulse waveform which will lead to very low residual vibrations. If an appropriately chosen waveform and time duration of the seeking pulse waveform is employed, very low track seeking residual vibrations and quick track access can be achieved. The method has been developed based on a conceptually simple, yet representative, HAA model. The effectiveness of the proposed method has been verified through extensive analytical calculations, finite element simulations and experimental testing.

Currently, ultrasonic wire bonders with precision capillary tips are widely used for bonding wires to IC chips and circuits. In the bonding process, a metallurgical bond is achieved through the proper transmittal of ultrasonic energy under pressure to the bond surface at a constant ultrasonic frequency (60 kHz and above depending on the wire materials used). However, bond quality and strength are affected significantly by the change of the vibration characteristics of the bonding capillary and system during the bonding process, which is not yet well understood. Research effort has been made to develop a noncontact, nonperturbative and low-cost monitoring device for vibration measurement, in order to improve bonding quality control. This paper reports the initial study on the understanding of the capillary vibration. The capillary vibration characteristics, such as natural frequencies and vibration modes, are first analyzed using the finite element method. The predicted displacement profile along the capillary tip was compared with measurements using a noncontact laser vibrometer, and good agreement between prediction and measurements was obtained.