Samantha. What is it? –It is a Wi-Fi interface for the Lego Mindstorms –It replaces the Bluetooth connection for running matches It is mostly for running.

Samantha

Samantha

• What is it?– It is a Wi-Fi interface for the Lego Mindstorms– It replaces the Bluetooth connection for

running matches• It is mostly for running matches• You theoretically can download software over this

link

Samantha

• How does it hook up to the NXT?– The Samantha hooks up to the USB port on

the NXT – It does not use up a sensor port– It will see the “name” of your NXT and use

that to identify your NXT to the field control system

Samantha

• What does it mean to me for competition?– You do not have to bring a laptop to the

competition field!– You do not have to bring joysticks to the

competition field!– All you have to bring is your robot (and drive

team)– Matches will be controlled from a central

computer

Samantha

• What does it mean to me for practice?– You will need Wi-Fi to test your robot under

actual competition conditions– Samantha can use an existing Wi-Fi

infrastructure• Configuration is done using the Samantha Network

Configuration program (included with FCS)• The network information is written to a file on a

USB flash drive.• This file is read by the Samantha to configure the

network

Samantha

• What does it mean to me for practice?– The Samantha FCS will be available for download.

• Team Resources• FTC Toolkit• Field Control System Resources

– The installation package also provides utilities for verifying the network connection

• RobotC– Samostat

• Labview– Samostat– Communications_status

Samantha

• What is Samostat?– The Samostat program is a useful Wi-Fi

status and network verification tool– The first message you may see is Acquiring..

Samantha

• What is Samostat?– When the Samantha module connects the

network information is displayed on the screen

Samantha

• What does Samostat tell me?– The first line is WiFi Stat and the software

version number (1.42 in this case)– Next is the IP address of the module– Following that is a series

of number indicating the

basic state of the TCP

connection

Samantha

• Networks line?– These are the Wi-Fi networks the Samantha

has detected. There are two character positions in front of the network names. If the first character is an * then this is the connected network. If thesecond character is an @,then it is an ad hocnetwork, if it is blank, it isan infrastructure network.

Samantha

• What is the Comunications Status program?– The Communications Status (LabView only)

program is a communications monitoring tool– It tracks the messages being received in the

NXT mailbox and reports the status to the NXT LCD

Samantha

– The first line provides NXT and external battery voltage

• Msg Cnt is the number of messages received• Msg Rate is the packet to packet time (not averaged)• Msg Delay is the additional packet to packet time relative to

the expected 20 messages per second time slice. This is reset to 0 every 5 seconds.

Samantha

• The Communications Status program– This is strictly meant as a verification tool for

message traffic integrity– The writes to the display take too long, and

the messages get read too fast to all be visible to the user.

– The data displayed is provided as a “reasonable” representation of the message traffic.

Samantha

• Mounting– Preferred is vertical with USB facing down– Horizontal has most potential for loosened

connections, but this can be mitigated with proper strain relief

– Use zip ties to hold cables in place– Mount as high as possible– Do not bury it behind a bunch of metal

Samantha

The ½” gear hub that is supplied in the TETRIX kit is the right size and is a good choice to use as a spacer for proper strain relief with the original Samantha. Experiment to find the best solution with the newer modules.

Samantha

• Robot Power Management Using Anderson Powerpole© Connectors

• This comes from a document on the USFIRST web site Samantha resources

Samantha

• The newer Samantha units work the same as the older units. The connectors seem to be a bit more rugged.

• CAUTION– If you are loading new network information (re-flashing

the unit). Do not attempt to only change the encryption type for a network. The Samantha does not seem to correctly update if only the encryption has changed. It is best to rename the network to something different then flash again to set the proper name and encryption.

Samantha

• Any Questions?