Check - which systems from a craft can not be tested on a ground but in orbital flight. The critical one
(a) GPS data collection from raw data ID 30,
(b) orientation system (on a ground it can be only a simulation),
(c) communication system with 2.4 GHz,
(d) orientation system with 3 axes
(e) astro-navigation system (calculation direction to the center of Earth, and star matching system).
(f) backup communication.

GPS any way needs to be developed for correct main impulses direction. Electronics can be done in 2 weeks, and software will be major development. First it will transfer ID30 satellites reading using backup communication. Then by formula on a ground calculates Keplers elements and transfer orbit params back using backup system. Weight for a sensor 25 g. For ground tests can be used the same TRA app with 5 GPS satellites Keplers element and simulation of a ID30 data. When formulas finalized and errors estimated the same source code can be inserted into a flight main computer. No backup calculations of Keplers elements in microcontrollers.

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