It may be a device to test the aerodynamic loadings on the front wing as the car is out on track. Obviously on-track data is different to windtunnel data (as Honda found out a couple of years ago).
I think you're right with your assumption, Greyhead, this definitely looks like measuring equipment they would use during testing only. The wires connecting it to parts of the front wing suggests it's indeed some kind of load testing / measuring device.