A: 1. Limited camera resolution 2. Limited bandwidth over USB 2.0 3. Baseline of plane
Higher resolution cameras, and USB 3.0 will allow detection at longer distances.
Q: Why not look at multiple depths, instead of just one depth?
A: These CPUs were maxed with just one depth, at 120 Hz More powerful CPUs are already on the market, and will enable multiple depths.
Links to the research papers:
Andrew J. Barry and Russ Tedrake. Pushbroom Stereo for High-Speed Navigation in Cluttered Environments. In Proceedings of the 2015 IEEE International Conference on Robotics and Automation (ICRA), May 2015. http://groups.csail.mit.edu/robotics-...
Andrew J. Barry, Helen Oleynikova, Dominik Honegger, Marc Pollefeys, and Russ Tedrake. FPGA vs. Pushbroom Stereo Vision for MAVs. Vision-based Control and Navigation of Small Lightweight UAVs, IROS Workshop, 2015. http://groups.csail.mit.edu/robotics-...