After many hours of discussion and debate it seems the Bonus Features could be an IR Sensor. A commenter by the name of "wtff" explains on the Notion Ink Blog
Linking the riddle to the Hex number:
"Concerning the riddle about the hex number (“-D5720A80″:
There seems to be a quite some speculation about it going on, despite the fact that it has been pointed out, that – interpreted as a unix timestamp – the number resolves to Tesla’s birthday.
First of all: congratulation to those who resolved the riddle or took a part in it. Good work!
I meant to add that to my mind, we can all rest assured that the timestamp interpretation is the correct one. The fact that the timestamp resolves into a GMT date ending in 00:00:00 is already evidence enough for the hex number being a nix timestamp. The additional fact that this timestamp coincides with Teslas birthday just casts this theory into bronze.
Further speculations about FCC codes seem reasonable to me only under the assumption that a grantee can choose his own EPC code but I don’t think this is possible.
So, Tesla it is then."
Possible use cases:
"There is a lot to be had for little money from a simple set of IR emitter/receiver:
- as you decribed: infrared imaging at night, or the fotographic effect of altering daylight images by incorporating the infrared spectrum
- a universal remote control for TV / hifi equipment
- measuring distances
a ) for supplication of camery images with depth information, in order to achieve kinect-like game control
b) for actual distance measurement between a reference point on the adam and an object
all this and more can be realized by one and the same set of equipment and the price for that is LOW! Just an IR diode and a webcam that is there anyway. (It is usual for photographic sensors to be sensitive to the IR spectrum and one could employ a small extra budget to get components that do specifically well in that regard. )"
In various Videos Rohan's hints at the possibilities made available to the team by the hardware present in the Adam such as the 12mp Camera.
I am inclined to agree with wtff's observations and justification.
The second possibility seems to be that the code is the second half of an FCC related code. Greg (a Notion Ink Blog Commenter) explains: "FCC assigns the grantee code (Y2G in this case) and Notion Ink designates the EPC. So the resulting FCC ID for the adam will eventually be Y2G-D5720A80."
This theory does seem plausible but does not lend itself to solve Rohan's riddle, Therefore creating some doubt. It could be that both observations are indeed true.
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