Flock data

The Flock data was based on a similar setup to the Nintendo data. In fact, the same software (with minor modifications to cope with two sets of data: one left, one right) was mostly used. However, much improved equipment was used.

The new equipment consists of:

• Two Fifth Dimension Technologies (5DT) gloves, one right and one left.
• Two Ascension Flock-of-Birds magnetic position trackers, one attached to each hand.
• A four-port serial card to cope with four data sources.
• A PC (128MB RAM, Intel Pentium II 266MHz) was used.

In terms of the quality of the data, the Flock system was far superior to the Nintendo system. Firstly, this was a two-hand system. Secondly, each position tracker provided 6 degrees of freedom - i.e. roll, pitch and yaw as well as x, y and z. The gloves also provided a full five fingers of data. But the big improvements were in resolution - both accuracy and temporal. Position and orientation were defined to 14-bit accuracy, giving position information with a typical positional error less than one centimetre and angle error less than one half of a degree. Finger bend was measured with 8 bits per finger, of which probably 6 bits were usable once the glove was calibrated. The refresh rate of the complete system was close to 100 frames per second; and all signals had significantly less noise than the Nintendo data.

Samples from a single signer (a native Auslan signer) were collected over a period of nine weeks. In total, 27 samples per sign, and a total of 2565 signs were collected. The average length of each sign was approximately 57 frames.