Wednesday, April 8, 2009
light strip proof-of-concept
On April 7th I completed construction and testing of the proof-of-concept WiiCane light strip. The purpose was to test the feasibility of using the WiiCane setup with infrared LEDs embedded in a strip on the floor. The light strip provides waypoint markers which can be detected by the remote and software to provide additional positional and movement data. The active LED strip is an improvement on and supercedes the previous concept of using reflective strips on the floor to provide additional movement data.
This version was built as a six-foot strip, with infrared LEDs spaced 12 inches apart. The LEDs are constantly illuminated, drawing approximately 50 mA each and supplying 7 mW of light with a wavelength of 940 nm. The LED package chosen emits with a 34 degree viewing angle.
Initial results look very good - the remote is able to see the LEDs at a fairly oblique angle, down to about 50 degrees off-axis. The lights show up at a distance of at least two or three feet, even against moderately-bright background lighting. The bottom picture shows the view reported by the remote when two LEDs are in the remote's field of view.