Overview

MIRO has stereo cameras, one in each eye. The cameras perform automatic exposure and focus is fixed with a large depth of field.

Geometry

All figures in this section are approximate—some variability is present between individual physical robots.

MIRO's eyes are fixed in the head, at 45 degrees of elevation and 27 degrees of divergence from straight ahead in each (that is, the horizontal divergence between the cameras is 54 degrees). Each camera has a horizontal/vertical field of view of 90/67 degrees and the aspect ratio is 4:3 (pixel aspect ratio is 1:1). The resulting stereo overlap region is greater than 30 degrees, and the two cameras together provide a wide horizontal field of view of greater than 140 degrees.

Eyelids

The two eyelids can be moved together either under direct servo control or using the built-in blink generator.

Timing

Frames from the two eyes are delivered asynchronously. When the cameras are both well lit, they will deliver frames at the same frequency and at a fixed time offset (if they have been well lit since they were last reset, the time offset will be near zero). In general, however, neither synchronicity nor frequency matching between the two cameras is guaranteed, since they will automatically reduce their frame rate if there is insufficient light to deliver frames at the selected rate.