What i learned

Sumo Bots

Building an autonomous sumo robot can be easy. You need to assemble a few key parts:
Power train - You need good gear motors. I look for gear motors everywhere (Ax man surplus stores around the Twin Cities area are a good source). Lego gear motors are also pretty good.
Body - Most sumo bots are built wedge shaped. Build it tough, it will take a beating.
Power - Select a reliable power source. I use 6-9 volt packs of rechargeable batteries.
Sensors - Detecting the edge of the ring is a must. I have used CDS cells, IR receiver and transmitter pairs and mechanical switches to detect the ring edge. Detecting the opposing robot is optional. You can use IR, acoustic or even mechanical bump switches.
Brains - The brains of a sumo bot can be quite simple. A basic control flow can be:
Select a direction to go. This can be based on detecting the opponent, picking a random direction, or just turning a little bit at a time one direction.
Go straight
If you detect the edge of the ring back up and try again.
Go to 1. This control flow can be hardwired or programmed into simple microcontroller such as a basic stamp. Smarter controllers will let you do complex actions based on sensor inputs.
So far I have built 4 sumo robots:
CAM: Was my first sumo bot and was built around a 555 timer. It runs forward till it detects the white ring edge, then trips a relay to reverse a motor for a short while and tries again. The front wheels turn when it goes backwards, causing it to go a new direction.
Bat and Rhino: These are similar stamp based robots that use CDS cells to detect the white line and IR emitter / receiver pairs to look for the opponent. The programs for these robots follow the flow described above in the brains section. You can see pictures of bat, rhino and other bots at: http://www.tcrobots.org/members/rwhil.htm
Brick: This robot is built with only Lego Mindstorm parts. The motors in the kit are great with excellent torque. The light sensor is great for detecting the white ring edge. Since it has no sensors for detecting the opponent, its program just selects a random direction, goes forward till it finds the ring edge, backs up a little, and repeats. It took me two evenings to build and much to my dismay, it regularly beats my other robots that I have put many more nights into building. Here are some useful web links:
Building a sumo bot: http://www.cercot.demon.co.uk/SUMO/BUILD.HTM Another bot building example: http://www.ece.concordia.ca/~dave/project/intro.html Rules and a simple bot circuit: http://www.robotgames.com/sumo.htm Seattle Robot Society Sumo Rules: http://www.seattlerobotics.org/nwrs/index.html Other sumo rules: http://members.tripod.com/rksingh21/sumo.htm
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Skype calls
the class called a guy in norway. he talked about the economy and the government. we asked him some personal questions about his religiouse aspects and such.

file sharing

a method of distributing electronically stored information such as computer programs and digital media. File sharing can be implemented in a variety of storage and distribution models. Current common models are the centralized server-based approach and the distributed peer-to-peer (P2P) networks.

Webhosting is also used for file-sharing; it is similar to the server-based approach, but uses the Hypertext Transfer Protocol (HTTP) and related technologies for file transfer. In small communities popular files can be distributed very quickly and efficiently without extra software in addition to the ubiquitous web browsers. Web hosters are independent of each other; therefore contents are not distributed further. Another term for this is one-click hosting.

To understand peer-to-peer file sharing and what was indeed the very first implementation of peer-to-peer file sharing, you need to go back before the popularized form of the Internet as we know it. First use of Peer-to-peer file sharing was on a network similar to the Internet known as WWIVnet. WWIVnet was like FidoNet but it used a distributed model of nodes where traffic was re-routed based on the shortest distance between nodes. It worked very much like the Internet but without a constant always on connection. The Internet existed prior to WWIVnet, but it was only available to academic institutions, governments and large corporations. FidoNet was a hierarchical (server/client) based network thus not peer-to-peer. WWIVnet was the first widely available distributed network model that you could bring to your home. That all being said, it did not have the capability to share files built in. It was not until the introduction of Linker34 by Jayson Cowan did we see the first P2P application over a distributed end user network.[2] Requests for file lists and specific files where handled by the peer much in the same way as second generation peer-to-peer file sharing and no central server was used for this process.

Peer to Peer vs Client-Server

Client-Server

In a client-server environment like Windows NT or Novell NetWare, files are stored on a centralized, high speed file server PC that is made available to client PCs. Network access speeds are usually faster than those found on peer-to-peer networks, which is reasonable given the vast numbers of clients that this architecture can support. Nearly all network services like printing and electronic mail are routed through the file server, which allows networking tasks to be tracked. Inefficient network segments can be reworked to make them faster, and users' activities can be closely monitored. Public data and applications are stored on the file server, where they are run from client PCs' locations, which makes upgrading software a simple task--network administrators can simply upgrade the applications stored on the file server, rather than having to physically upgrade each client PC.
In the client-server diagram above, the client PCs are shown to be separate and subordinate to the file server. The clients' primary applications and files are stored in a common location. File servers are often set up so that each user on the network has access to his or her "own" directory, along with a range of "public" directories where applications are stored. If the two clients above want to communicate with each other, they must go through the file server to do it. A message from one client to another is first sent to the file server, where it is then routed to its destination. With tens or hundreds of client PCs, a file server is the only way to manage the often complex and simultaneous operations that large networks require.

Peer to Peer

A peer-to-peer network allows two or more PCs to pool their resources together. Individual resources like disk drives, CD-ROM drives, and even printers are transformed into shared, collective resources that are accessible from every PC.
Unlike client-server networks, where network information is stored on a centralized file server PC and made available to tens, hundreds, or thousands client PCs, the information stored across peer-to-peer networks is uniquely decentralized. Because peer-to-peer PCs have their own hard disk drives that are accessible by all computers, each PC acts as both a client (information requestor) and a server (information provider). In the diagram below, three peer-to-peer workstations are shown. Although not capable of handling the same amount of information flow that a client-server network might, all three computers can communicate directly with each other and share one another's resources.

End of Skype

Skype was so FUN!!!!!!!!!!!

we got to play games, use cams, talk with people, and we also got to do some coferense calls!!!

its such a sad day...we ending our learning of skype and are moveing on...

SAD FACE!!!! I=(

switching to skype

the switch to learning to use skype has been so fun. we got to use webcams, microphones, and other awsome features.