Lego PC Bot Software

We would like to use the Floor Finder obstacle avoidance technique described in the Obstacle Avoidance tutorial to move the robot around the room avoiding obstacles that are not the same color as the floor plane.

We load in the following robofile which performs this task specifically using the Lego NXT robot.

Once the video has started and verified we can turn on the NXT. The final task is to press the green Start button in the RoboRealm popup button interface to actually start the robot. This provides a quick way to start and stop the robot and is even possible to click while the robot is moving (tap the mouse pad to click the button).

Videos

Notes:

1. The biggest issue (after Sability of the platform) is the viewable area of the camera. As the camera is pointed towards the ground and the robot base is quite wide the camera cannot see a wide enough view in front of the robot in order to avoid all obstacles. It is possible for an obstacle to slip by the camera view and collide with a wheel. This issue can be solved by either using more than one camera (one for each wheel) or a camera with a wide field of view.

2. There are a couple of issues to solve to make this a reliable platform for continuious use. Improving stability by using a different design or more parts from a second NXT kit would help. In addition the Asus Eee will only last about an hour in terms of power. As the system does not have a charging solution continious operation is not possible at this point. Note that there are two power systems in operation with this platform, the laptop being one and the other being the NXT.

3. Note that none of the other sensors available in the Lego NXT are NOT being used. One could improve the reliability of this implemention by adding in the other sensors. The sensor attachment side of the NXT is kept clear to allow for these additions. Again, all these sensors could work in conjuction with the onboard vision system either within the NXT or combined with the vision logic within RoboRealm.

The End

That's all folks. We hope you've enjoyed this little adventure into an application of machine vision processing and have inspired you to download a free trial of our software.

If you have any questions or comments about this tutorial please feel free to contact us.

Have a nice day!