368 research outputs found

    Interaction indirecte en réalité virtuelle à l'aide d'un médiateur

    Get PDF
    Currently many researches in the field of multimodal interfaces (input, output) have been made in order to be able to achieve complex tasks merely, naturally, and quickly. Expert interfaces should be considering the risks resulting from an ordered action, to prevent any harmful action and to suggest possible alternatives. Taking into account the complexity of the tasks to achieve and exponential growth of information, the adaptive systems are henceforth essential to make possible and facilitate the work of the operator. A good man-machine interface is thus strongly required. We note that multiple interaction and manipulation techniques are currently available, but at this time, the characteristic tools of the WIMP paradigm (Windows, Icons, Menus and Ppointing device) did not find their equivalent in 3D interfaces. There still remains way to make to be able to find the perfect tool and to enforce it as a standard for the 3D interfaces and applications. Therefore, our research was focused gradually towards the proposal for a mediating interface: a very adaptive and functional interface, intended to simplify to the maximum the human interaction in the execution of complex work. The concept of the "mediator" might be clarified in the following way, i.e.: A user in full immersive system named mediator world will be able to control or interact a front distance, through an intermediary haptic devices, on another virtual or real world named controlled world. Let us recall that the Human needs simple tools to be able to achieve complicated tasks. In such a case, one of the ultimate goals is to make the machine adapt to the human instead of forcing the human to adapt to the machine

    Data acquisition and imaging using wavelet transform: a new path for high speed transient force microscopy

    Get PDF
    The unique ability of Atomic Force Microscopy (AFM) to image, manipulate and characterize materials at the nanoscale has made it a remarkable tool in nanotechnology. In dynamic AFM, acquisition and processing of the photodetector signal originating from probe–sample interaction is a critical step in data analysis and measurements. However, details of such interaction including its nonlinearity and dynamics of the sample surface are limited due to the ultimately bounded bandwidth and limited time scales of data processing electronics of standard AFM. Similarly, transient details of the AFM probe's cantilever signal are lost due to averaging of data by techniques which correlate the frequency spectrum of the captured data with a temporally invariant physical system. Here, we introduce a fundamentally new approach for dynamic AFM data acquisition and imaging based on applying the wavelet transform on the data stream from the photodetector. This approach provides the opportunity for exploration of the transient response of the cantilever, analysis and imaging of the dynamics of amplitude and phase of the signals captured from the photodetector. Furthermore, it can be used for the control of AFM which would yield increased imaging speed. Hence the proposed method opens a pathway for high-speed transient force microscopy
    • …
    corecore