Project week 2

Wednesday and Thursday (08/12 an 09/12)

From 9 o’clock until 16:00

Participants: Michael Kaalund and Brian Hansen

Shcedule of the week
-Get RGB readings and calibration
-RGB test, measuring color over distance
-Get sonice reading and calibration
-distance testing, can we detect lego color towers (bunch of matching bricks)
-Construct a simple environment for testing


Progress (notes)
We did ...

RGB sensor:

We had some problems with the RGB sensor in our lejos, that we could'nt get it to read from the sensor because of some bugs in the ”Classes.jar” and at first we could find some chatter about you'll need to recompile the ”Classes.jar” package and reflash the NXT (source: http://lejos.sourceforge.net/forum/viewtopic.php?t=2165&highlight=colorsensor).

After some additinonal searches we found another thread in the lejos forum, where they had found the problem.

The problem lies in that the new RGB sensor acualt uses the checksum. They have found that the error is in the ”SensorPort.java”, and as the checksum is'nt really being used in the other sensors, it has'nt been fund before. The linies that creates the checksum is between 452 to 454 (see the picture)

After we recompiled the ”Classes.jar” and our test program, we runnend some test of the RGB sensor, where we discovered, that we could'nt meassure further that a couple of centimeters away. This meanes for our robot that it either shall turn (the hole robot) around and drive to the object or we are going to make some constructions changes, so that the sensor arm will be extended so the sensors reaches to the sides. Update: We made an quick measuring of the RGB sensor, where we measured the minimum distance to the an object is 0,5 mm and the maximum distances is 40 mm.

UltraSonic:

We did an test on the ultrasonic sensor, the distances is measured from the sensor.

Real distance : Measurement from ultrasonic sensor.

--------------------------------------------------------------

1 cm : 4

2 cm : 5

3 cm : 5

4 cm : 6

5 cm : 7

6 cm : 8

7 cm : 9

8 cm : 10

9 cm : 12

10 cm : 13

11 cm : 13

12 cm : 14

13 cm : 15

14 cm : 16

It gives 24 when there is no object in front of it. As there can been seen from our measurements, there is instances where it in two measurements gives the same reading.

Environment:

The area is 237 x 104,5 cm in it dimensions, futher the environment is defined to not have any obstructions 30 cm from the edge.

Behavior:

The way we imagning how the robot is going to accomplish the main tasks

We have decided here at the beginning, there are two "modes"
The first "fashion" it must run is "define outline" where to find the edge around the track. While driving, the swing's sensor to find the edge, if it were to find a red or ayellow pad, then it will just "remember" where it is, find back there after it has foundall around.

The second mode is where it should not have found the red or the yellow brick in its"define outline" mode, then starting its "search"mode. Where the goal is to find thered block, then send its coordinates to the computer.
When running in search mode and then it will still swing the sensor back and forth acircular motion, to identify possible obstacles and respectively the red and yellowbrick.
For this "search" mode, there will be various search methods. descibed below.

Next week
- Get the robot to define outline
- Search drive with and without RGB sensing
- Find atleast one tower.
- Send koordinate for tower