NEWS

5/3/07 New Chassis for Serial Button Box! See below...

Updates to the 31 Input USB Response Box

The first incarnation of the 31-input response box utilized a mechanical joystick, the shaft of which could be rotated 360 degrees. The joystick was machined to rest on the down-center position, rather than center-center as is common. Since the X-axis of was locked, the joystick could only be moved up and down (-Y to + Y).The box was programmed to output signals for clockwise and counterclockwise shaft rotation, as well as partial (Y = 0) and complete (Y = +Y) motion along the vertical axis.

It was later determined that the resolution of this joystick was lacking. The precise hand movements the researcher was hoping to measure were lost because the system was fairly insensitive.

To solve this problem, we replaced the mechanical (microswitch) joystick with a precision analog joystick. A small analog to digital conversion circuit was designed which allows 'trigger points' to be set on both the Y and rotational axis. This new circuit allows nearly 65,000 degrees of resolution - a vast improvement over 2 fixed microswitch positions. The X-axis of this joystick is also locked.

These trigger points are programmed into a small microcontroller, and each can be adjusted as needed.

It is anticipated that the new design will greatly increase the precision of the data collected.