The link below if for the PX4 OF Kit at 3DR. Anyone have any ideas or online links about how this might be installed on Solo. I get the impression from 3DR that they have no plans in 2015 to release an Optical Flow solution. It was not even an option on today's 3DR survey. The one from DJI works great but nothing soon from 3DR.
https://store.3drobotics.com/products/px4flow
https://store.3drobotics.com/products/px4flow