fischertechnik COMPUTING ROBO MOBILE SET 8 Mode D'emploi page 46

R
O B O
GB+USA
4 4
4 4
M S
O B I L E E T
A s s i g n m e n t 1 ( L e v e l 2 ) :
● First the robot should drive straight ahead. If it encounters an obstacle (I4) to the
left, it should back up a bit and then move to the right.
● If it encounters an obstacle (I3) to the right, it should back up a bit and then move to
the left.
Ti p s :
• Obstacle recognition when going backwards will be set aside until later.
• The main program queries the pushbutton sensors. Depending on which pushbutton sensor is
activated the model evades to the left or to the right. In each instance this is done using a
subprogram.
• The pulse count when turning right should be different from the pulse count when turning left (e.g. 3
pulses to the right, 5 pulses to the left). Otherwise it can happen that the model drives into a corner
and gets struck because it turns to the left and right in equal amounts.
• The finished program is called Obstacle 1.rpp.
There are two things the obstacle recognition model does not yet know how to do: It cannot recognize
obstacles when going backwards. Equally it does not yet recognize when there is an obstacle directly in
front of it. But it could be able to recognize both. If I5 is pressed while going backwards an obstacle is
behind the model. Are I3 and I4 activated at the same time while going forward an obstacle is located
directly in front of the model. In this case the robot could turn 90° immediately. In all we now have the
following possibilities the robot should be reacting to:
Pushbutton
O b s t a c l e S e n s o r
right only I3
left only I4
in front I3 and I4
behind I5
Some new program elements such as Operators (e.g. AND, OR) from ROBO Pro Level 3 can help you to
solve this problem in an elegant way. Level 3 offers you the possibility to exchange data between
different elements by using orange arrows. Switch to that level in the software to take full advantage
of these options. It would now be a good idea to take out the ROBO Pro manual and read chapter 5
carefully. After that you'll be ready for the next assignment.
A s s i g n m e n t 2 ( L e v e l 3 ) :
● Modify your obstacle recognition program in such a way that the model will react
as described in the table above.
● Take advantage of the possibilities offered by ROBO Pro level 3.
4 4
4 4
A B
C T I V I T Y O O K L E T
R e a c t i o n
move to the left (turn approx. 30°)
move to the right (turn approx. 45°)
move to the left (turn approx. 90°)
Only queried when going backwards. Stop, then
continue evading as planned.