The design and implementation of a DSP-based tactile vocoder system.

摘要

In this thesis, a laboratory prototype of a wearable, DSP-based tactile vocoder is designed, simulated, implemented, and tested. In conjunction with a software simulator implemented in the "C" language, the DSP-based tactile vocoder provides a powerful means to examine the effects of parameters which were previously difficult to change.;The DSP-based tactile vocoder incorporates a new type of tactile stimulator. These stimulators are studied in detail with respect to electro-mechanical frequency response and transfer characteristics. A novel driving waveform and driver configuration is proposed, tested, and incorporated into the DSP-based tactile vocoder.;The laboratory prototype is wire-wrapped on a 9 x 9 inch board. There is a considerable amount of space left on the board for prototype circuits. The prototype contains an interface to a personal computer (IBM PC/AT compatible). (Abstract shortened by UMI.).;A TMS320C25 DSP is used to replace a large portion of the signal processing hardware. The DSP implements a filter bank with 16 bandpass filters, spaced according to critical bandwidth theory. The outputs of the filter bank are full-wave rectified, low pass filtered, logarithmically compressed, and transformed into a bipolar, pulse-width-modulated driving waveform for the tactile stimulators.