LAB.5 - Racing competition part 1

Date: 30/9-2010
Duration of activity: 11:15 - 17:00:
Group members participating: All
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Schedule for the day:
- Get the existing line follower to work
- measure value from the NXT sensor
- implement the old sensor system
- measure values from the old sensor
- run line follower with old sensor
- improve sweep mode (lost black and it spins around, not a good solution)
- build soulution that takes care off all the issues

Problems and progress:
- NXT sensor green and black values in same region
- Smal bugs corrected with old sensors
- First linefollower showed loss of black line and not enough power to wheel wen driving in cirkels
- Smarter turning system failed first test, there might be problems with a motor.

- cant sample fast enough, removed screen output, but it didnt work.
- decided to move forward with a new sweep method
- implementet a 2 and then 3 sensor setup, attempted to improve line following but stil lagging

Measurements
The values are from the blackwhitesensor.java
- NXT sensor green 32-34
- Old sensor
white 32-35
green 22-24
black 18-21
- Old sensor raised 1cm
green 27
black 23
- Motor +70+ and -70
for 100 ms 9 grader
for 150 ms 2*9
for 550 ms 90 grader
that means the turn function is turn(degrees){ sleep(degrees/9*50ms + 50ms}
there is some mismatch when returning and overall but that is because of overshooting and motor not delivering the same power
- No traction uphil, experimentation with different wheels, and more speed
- we are using 3 sensors to determine the borders and and will try to optimize speed by using the total width of the sensor hookup

Detailed description of solution
- The new sweep method.
As shown on the picture the system is intended to turn lets say 10 degres left and then 20 degress to the rigth to compensate for the degrees rigth. this setup increses ontil the devise has turned 180 or has hit a black or green spot.

- 2 sensor solution: pseudo code (LS = left sensor, RS = Right sensor, W = white, B = black)
if LS and RS == B
then forward
else if LS == B and RS == W
then turn left
else if RS == B and LS == W
turn right
else
sweep mode

- 3rd sensor system improves the system by letting the car drive as long as the middle is black or one of the other sensors,exception if all are black, then there is a stopline.
example the car drives so the middle turns white but left is stil black

Final Status:
- all states of state machine that manage sensors not implemented
- no solution to detecting and turning in the corners
- no solution to stopping and turning in top-platform