Robotics with the Boe-Bot text v2.2
Chapter 6: Light Sensitive Navigation with Photoresistors · Page 219 
 PAUSE 20 
 RETURN 
Your Turn – Adjusting the Performance and Changing the Behavior 
You can adjust the program’s performance by adjusting the scale factor term in this 
constant declaration: 
' Average Scale factor 
LeftThreshold CON LeftBright + LeftAmbient / 2 * 5 / 8 
RightThreshold CON RightBright + RightAmbient / 2 * 5 / 8 
If you change the scale factor from 
5
/
8
 to 
1
/
2
, it will make the Boe-Bot less sensitive to the 
flashlight, which may (or may not) lead to improved flashlight control. 
√  Try different scale factors, such as 
1
/
4
, 
1
/
2
, 
1
/
3
, 
2
/
3
, and 
3
/
4
 and make notes about 
any differences in the way the Boe-Bot responded to the flashlight beam. 
By modifying the 
IF…THEN statement in the example program, you can change the Boe-
Bot’s behavior so that it tries to get the light out of its eyes. 
√  Modify the IF…THEN statement so that the Boe-Bot backs up when it detects the 
flashlight beam with both photoresistor circuits and turns away if it detects the 
flashlight beam with only one of its photoresistor circuits. 
ACTIVITY #6: ROAMING TOWARD THE LIGHT 
The example program in this activity can be used to guide the Boe-Bot through exiting a 
fairly dark room toward a doorway that’s letting in brighter light. It also allows for much 
better control over the Boe-Bot’s roaming by casting shadows over the photoresistors 
with your hand. 
Readjusting the Photoresistors
This activity works best if the photoresistors’ light collecting surfaces are pointing 
upwards and outwards. 










