ITK 168 Decisions

Dr. Doug Twitchell

September 20, 2005

IF

What if I want the robot to pick a thing up if there’s one there, but not pick a thing up if there isn’t?

if

if(bob.canPickThing()){bob.pickThing();

}

if(<<test>>){<<list of statements>>

}

if

if(bob.canPickThing()){bob.pickThing();

}

if(<<test>>){<<list of statements>>

}

boolean statement

if

if(bob.canPickThing()){bob.pickThing();

}

if(<<test>>){<<list of statements>>

}

boolean statement

true or false

if Flowchart

if

Can I use this to see if there is a wall in front of me?

if

if(bob.frontIsClear()){bob.move();

}bob.turnLeft();bob.move();

<<previous statements>>if(<<test>>){

<<list of statements>>}<<continue with following>>

if

What if I want it to left if the front isn’t clear?

if

if(!bob.frontIsClear()){bob.turnLeft();

}bob.move();

<<previous statements>>if(<<test>>){

<<list of statements>>}<<continue with following>>

if

Can I check to see if the robot is on a certain street?

if

if(bob.getStreet == 1){bob.move();

}

if(<<test>>){<<list of statements>>

}

== equal> greater than< less than>= g.t. or equal<= l.t. or equal!= not equal

while

what if I want the robot to pick up all of the things in a row

while

while(bob.canPickThing()){bob.pickThing();bob.move();

}

while(<<test>>){<<list of statements>>

}

while

while(bob.canPickThing()){bob.pickThing();bob.move

}

while(<<test>>){<<list of statements>>

}

boolean statement

true or false

while Flowchart

while

How about moving the robot until it gets to avenue 50?

while

while(bob.getAvenue() < 50){bob.move

}

while(<<test>>){<<list of statements>>

}

if…else

What about when want to turn right if wall is in front and turn left otherwise?

if…else

if(bob.frontIsClear()){bob.turnLeft();

} else {bob.turnRight();

}bob.move();

if(<<test>>){<<list of statements>>

}

boolean statement

true or false

if…else Flowchart

Example

How can we change the street cleaning robots to make it work better with if and/or while statements?