Day+Two+NXT

=**NETWORKS/GRAPHS/MAPS**=

For this class, we will build a Lego NXT robot and design the software for an android controller for the robot. To check its functionality, we will have a competition on the last day of our class.We will base this project on the information in the O'Reilly book "App Inventor" by David Wolber, Hal Abelson, Ellen Spertus and Liz Looney. We will probably need to make some modifications such as being able to change the motor power between the range of 0-100% because of reaction time and communication delays with bluetooth. If you don't consider this, you may not be able to "hit" any of the cities as you move your robot around the map you have been given. 100% power might be good for the straight-aways, but that much power will make turning any amount less than 360 degrees nearly impossible.

For our competition on the last day of class, we will have three different events where you traverse your map with your robot in different ways--a minimal spanning tree, a shortest path tree, and a traveling salesperson. You will need to attach a dry-erase marker to your robot so it will leave a trail on your map. The following information will help you to see how to complete each of the three events on your map so you can have a plan in place before the competition. Hopefully, the "minimal" part will show up in which team completes each event in the shortest possible time.

[|Background Information on Graphs (CSILM 1st activity only)]

[|Minimal/Minimum Spanning Trees (CSILM Activity One and Two)]
 * Definition in your own words:**

[|Shortest Path Tree]
 * Definition in your own words:**

[|Traveling Salesperson (minimal Hamiltonian Circuit)]
 * Definition in your own words:**

Which of the three would find the cheapest busfare? (shortest path) Which would minimize the total cost of a network connecting every node (phone network)? (minimal spanning tree) Which would take the least amount of material (wire, waterpipe, etc) to construct? (minimal spanning tree) Which of these would find the shortest route between two cities? (shortest path) Which would find the shortest circuit to get approval signatures from 6 department heads in different offices and bring it back to the president? (traveling salesperson) Which one always has one link less than the number of nodes? (minimum spanning tree) Which one always has the same number of links as nodes? (Traveling Salesperson) Which never has a loop? (shortest spanning tree and minimal spanning tree)

trees_minimal_spanning_hamiltonian.doc Word Worksheet

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= ANDROID PROGRAMMING =

= = =^= = = =<= = = =X= = = =>= = = =-= = = =V= = = =+= = = =Disconnect= || = Bluetooth connection = = = = move forward = = = = rotate left = = = = stop = = = = rotate right = = = = decrease power to motors = = = = move backwards = = = = increase power to motors = = = = cut bluetooth connection = ||
 * [[image:lhs-android/controller.jpg]] || =Connect...=