Hello,
can you give examples of photodiodes used as sensors in robotics? what are the applications?

 

Is Google broke?...

 

If Google is broke you could try https://duckduckgo.com/
The application is to sense the intensity of visible, IR or UV light. (Depending on the specification of the device which can be found on the data sheet.)
https://duckduckgo.com/
Les.

 

Is Google broke?...

no

 

To detect changes in light...
Obstacle avoidance, line following, edge detection, near field communication,etc...