YARB (yet another robotic blimp) is back in business, now carrying a new Surveyor SVS (stereo vision system) controller with a pair of Blackfin cameras. The new rig weighs about the same as the previous single-camera setup with added sensors. It is actually a bit too light, so ballast has been added using washers held in place on the Wifi antenna.
There is a new simplified console that steers via 4 arrow keys for direction (up, down, left, right), the return key for reverse, and the spacebar to stop motors. Control via keyboard seems more direct than using mouse clicks, though the console will be able to steer via mouse clicks directly on the display window - this would work nicely with portable phones (iPhone, Android, etc).
Viewing of the live or archived video requires anaglyph (red/cyan) 3D glasses
. Here is a short 3d stereo video clip captured from the blimp ...yarbsvs1.avi (5.2MB)
It is fun to fly YARB around using stereo vision, but the real point of this exercise is to develop the functions that compute disparity between views of the two cameras in order to create a depth map. Similar to human depth perception, this enables the robot to measure distances to objects and obstacles without any additional ranging sensors (e.g. sonar, IR, laser). Work has already started to develop this capability in the Blackfin firmware.
Comments
The problem becomes more difficult once the camera is airborne, as an IMU is needed to estimate pose, i.e. to determine exactly where the camera is pointed in order to properly correlate depth map results. It is an interesting technical challenge.