1. What is computer science (CS)?
CS != programming
What is computer science (CS)?
Take CS 121

2. What is computer science (CS)?
CS != programming
What is computer science (CS)?
Take CS 121
"not equal to"

3. a vehicle, not a destination
CS != programming
programming : CS ::
machining : engineering
grammar : literature
Programming
equations : mathematics CS
a vehicle, not a destination

4. CS == computing science
Study of complexity (or complex things?)
How can it be done?
How well can it be done?
Can it be done at all?

5. CS == computing science
Study of complexity (or complex things?)
How can it be done?
How well can it be done?
Can it be done at all?
"equal to"

6. Information What information does Google work with?
What technical problems does Google face?

7. Information What information does Facebook work with?
What technical problems does Facebook face?

8. Information What information does the iPhone work with?
What technical problems does the iPhone face?

9. Computer Science and Information
Information is life’s fundamental building block
CS is a set of fundamental techniques for understanding and leveraging this information

10. Goal: whole-environment coverage with only local sensing…
Homework problem
walls
Picobot
Picobot
area not covered (yet!)
area already covered
Goal: whole-environment coverage with only local sensing…
inspiration?

11. Goal: whole-environment coverage with only local sensing…
Picobot
walls
Picobot
area not covered (yet!)
area already covered
Goal: whole-environment coverage with only local sensing…
iRobot's Roomba vacuum
inspiration!

12. NeWs Surroundings N E W S
Picobot can only sense things directly to the N, E, W, and S N W E S
For example, here its surroundings are
NeWs
Surroundings are always in NEWS order.
N E W S

13. How many distinct surroundings are there?24
== 16 possible …
news
News
nEws
neWs
newS
NEws
NeWs
NewS
nEWs
nEwS
neWS
NEWs
NEwS
NeWS
nEWS
NEWS
(won’t happen)

14. State
I am in state 0.
My surroundings
Are neWS.
Picobot's memory is a single number, called its state.
State is the internal context of computation.
Picobot always starts in state 0.
State and surroundings represent everything the robot knows about the world

15. Rules Aha! I should move N. I should enter state 0.
I am in state 0.
My surroundings
Are neWS.
Aha!
I should move N.
I should enter state 0.
Picobot moves according to a set of rules:
state
surroundings
direction
new state
neWS N
If I'm in state 0 seeing neWS,
Then I move North, and change to state 0.

16. Wildcards Aha! This matches nW state surroundings direction new state
I am in state 0.
My surroundings
Are neWS.
Aha! This matches nW
For a “wild card”, omit the letter and it will match walls or empty space:
state
surroundings
direction
new state nW N
E/e and S/s omitted here, so those directions may be wall or empty space

17. n -> N -> s -> S ->
What will this set of rules do to Picobot?
state
surroundings
direction
new state n
-> N N
-> X 1 1 s
-> S 1 1 S
-> X
Picobot checks its rules from the top each time.
When it finds a matching rule, that rule runs.
Only one rule is allowed per state and surroundings.

18. To do
Write rules that will always cover these two rooms.
(separate sets of rules are encouraged…)
hw0, Map 0
hw0, Map 2
but your rules should work regardless of Picobot's starting location

19. Alter these "up & down" rules so that Picobot will traverse the empty room…n N 1 X s S
state
surroundings
direction
new state
->
the empty room

20. Ideas for the maze?
the maze