Finally focused on this project a little.
In a nutshell the newly redesigned robot is now controlled from Bluetooth and the hacked drone from WiFi. All from an Android smartphone. Just got the pair working concurrently.
The robot trundled along whilst the drone took off. However, bad light stopped play as the drone positioning system relies upon a well lit scene below. It crashed!
This did prove that the robot and drone (+ human) can work together.
It also provided insights into human factors: the stresses & strains of the cognitive load, etc though that would ease with practice and different roles (currently experimenter/observer & pilot/driver).
The solar computer is also included in the new kit together with chargers etc but is yet to be integrated into the ensemble.
Hopefully, further opportunities will present themselves to work on this. Overall though progress is quite satisfactory.