If you think that our body is a long experience adaptation to the
environment, you can think it is some kind of a highly developed robot.
This organic robot is pretty nice to supply examples when building
electromechanical robots. A great percentage of humans just don't go
where they can't see or understand (as a protection system), so a robot
could do something similar, if the sensors can't determine what is
ahead, just avoid it, or apply a sticker in the robot's front head
"Adventurer" and reprogram the unit to find out what is in the unknown
and unreadable by the sensors space ahead.

A memory (E2prom) mapped is the best choice, one byte per each 4 sq
inches (aprox 10x10cm) can save 256 different meanings for that space,
along with a nice electronic compass and space positioning by beacon
triangulation.  We use something similar based on space/time.  When
traveling you can have an idea how far you are and probably "where" you,
also where is North or South based on the movement/distance/time, if you
sleep during the travel you got confused and you can't guess where are
you (you can miss it by hundreds or thousands of miles, and you will
need a compass or other trick to say where is South).

A beacon can be used somehow with a transponder that works as a
retransmitting system.  Your robot send a signal (ultrasound or
something) and the fixed stations (three) will receive it and send
another signal back. Your robot will receive it and analyze distances,
positioning, etc.  Each station has a different preset delay to send
back the signal, so one will not interfere with another, they can use
the same signal frequency (if ultrasound). In real you would be
recreating a GPS system.  This is cheap and works, and your robot will
know exactly where it is in the mapped area. You need to consider
problems with signal bouncing, walls, objects, and so on, that can
interfere in the "understanding" of time/space. Measurements of arriving
signal amplitude and delays can tell the robot several other important
informations.

Pre-programmed objects and locations would be nice, as power outlets
(battery recharging), hiding and resting areas and so on.  The
understanding of the environment is pretty nice, as for example stay in
a corner during the night (connected to a power outlet) and working as
an automatic light upon noise (it can light your way to the bathroom
night run), or working as a "learning repeater unit", turning on the TV
and select a specific channel at certain time of the day, because it
"saw" it happens several times at its "infrared receiver", or "yell" to
the kids to go sleep because it is after 10pm.

Just don't forget to include the organic robots common mistakes as
"marriage", "get fat", and other minor specialties. :)