08-LaunchTowerComputer.markdown

title	layout
Launch Tower Computer (LTC) Setup And Configuration	base

Launch Tower Computer Setup

Procedures for LAUNCH TOWER

Equipment List

• Launch tower computer
• 2x 12 volt batteries with Anderson PowerPole (APP) connectors
• Solar Panel
• LTC Field Box
  • Ignitor cables
  • APP cables
  • Shorting bar (sometimes called "launch key", but really called "shorting bar")
  • N connector coax for LTC antenna

Required Tools

• Miniature flathead screwdriver
• Large Phillips screwdriver
• DMM

Mount To Tower

1. Mount LTC box to the launch tower.
2. Turn power and arming switches on side bulkhead to off.
   • Verify that the arming switch actually turns off using the DMM in "beep" mode
3. Verify shorting bar is in place on side bulkhead.
   • Verify that shorting bar actually shorts using the DMM in "beep" mode.
4. Check fuse on side bulkhead.

Power Connections

1. Run battery cables though bottom bulkhead opening A, and connect to upper left Powerpole connector.
2. Run solar panel cables through bottom bulkhead opening A, and connect to lower left Powerpole connector.
3. Run ignition cables through bottom bulkhead opening A, and connect to upper right Powerpole connector.
   • Verify that the Away Box is empty (there's no shorting bar in it).
4. Attach launch tower computer interlock box to LTC with caribiner
5. Verify that the following indicators are illuminated:
   • BATT LED on the power interface board
   • SOLAR LED on the power interface board

Data Connections

1. Connect rocket umbilical cable to connector on lower left of bottom bulkhead.
2. Connect WiFi antenna cable to connector on lower right of bottom bulkhead.

Power-On

1. Launch control prepares for LTC bring up. Coordinate with launch control to proceed
2. Turn on the red LTC power switch on side bulkhead. (It should illuminate)
3. Verify that the following indicators are illuminated:
   • LTC power switch
   • PWR LED on power interface board
   • 5V LED on power interface board
   • PWR LED on ignition board
   • Power LED on BeagleBoard
   • USB hub power LED on BeagleBoard
4. Notify launch control team that LTC has been powered on. Wait for launch control team to confirm a remote connection to the LTC.
5. Replace bottom bulkhead cover plate.
6. Connect internal ignition battery. Notify launch control team. Wait for confirmation.

Launch Tower done, unless a launch test is requested.

Procedures for LAUNCH CONTROL

1. Make sure Launch Control is set up

2. Wait for notification of LTC poweron

3. Begin to ping the LTC on the wireless address

4. Start launch tower computer software:

    $ ./ltc.py
   

5. Wait for launch-tower-comm to connect

6. If launch-tower-comm does not connect, you may need to start the phidgetswebservice (it is automatically executed on system boot). To do this:

   • Open ssh session on LTC. Login as root and execute:

       # phidgetwebservice21 -v
     

LTC Poweroff Sequence

1. Confirm filesystem is in read-only mode
2. # poweroff -t now
3. Turn off power switch.

Reference

Suggested Radio Responses

1. LTC is connected to network: "I see your beagles coming in hot." -- Nathan
2. Confirm LTC you heard LTC is up: "Copy. Hot dogs on the move." -- Theo

LTC User Accounts

Username	Password
root	psaslv1b
ltc	ltc

LTC Network Configuration

Parameter	Value
WiFi (wlan0) IP Address	10.0.0.2
Ethernet (eth0) IP Address	10.10.10.1
USB Wifi Mac Address	00:c0:ca:32:b7:17
Ethernet Mac Address	2a:d3:77:aa:1e:f7

LTC WiFi Access Point Configuration

Parameter	Value
Channel	802.11b ch. 11
SSID	psas
WPA-2 Passphrase	psasrocket
AP IP Address	10.0.0.0/24
Static Range	10.0.0.1 - 10.0.0.9
DHCP Range	10.0.0.10 - 10.0.0.249

Common LTC Commands

• Reboot computer without delay:

   # reboot –t now
  

• Shut down computer without delay:

  # poweroff –t now
  

• View IP addresses assigned to network interfaces:

   # ip address show
  

• Make filesystem read/write

   # remount_root_rw
  

• Make filesystem read only

   # remount_root_ro
  

Figures