Sapphire Operations Working Page

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Vehicle Status

Updated 7/8/2004
  1. Sapphire is in "extremely extended" mission operations, which means he goes essentially untended for extremely long periods of time (i.e. months).  You can contact me (mas@wustl.edu) with questions.
  2. Sapphire's primary role is as a training tool for schools; schools have first priority in contacts.
  3. Sapphire's secondary role is as an APRS digipeater; I refer you to www.aprs.org for much more information on APRS.  Anyone is welcome to use Sapphire's APRS function (I refer you to http://web.usna.navy.mil/~bruninga/pcsat.html for a detailed discussion of digitpeating through spacecraft and the user service agreement that covers both PCSat and Sapphire is: http://web.usna.navy.mil/~bruninga/pcsat/contract.txt).
  4. Sapphire uses a slightly modified Kantronics TNC for packet communications.  However, please do not use the TNC's BBS; this is an unintended (ahem) "feature" accidentally left enabled.  We do not have administrative access to the BBS, and there is a glitch in the way that the TNC and CPU share login information such that using the BBS "locks out" operators from the CPU.  The only way to correct this is to reset the spacecraft (erasing all stored data in the process).

How to Contact Sapphire

These instructions are for the schools who have arranged to practice spacecraft operations through Sapphire.  If you want to participate, please contact Michael Swartwout (mas@wustl.edu).

The information here is just the data you'll need to contact Sapphire itself; more general information about how to build a station, find kep files, track, manage doppler shift, etc. is left as an exercise for the reader =-).

Level One:  Just listening

These instructions are for just picking up Sapphire transmissions from orbit and can be done by anyone, anytime.

  1. Sapphire is listed in most amateur & NORAD databases, under either Sapphire or NO-45 [Navy OSCAR 45].  In the official orbital element catalogs, Sapphire is object number 26932.  (You'll need that object number to pull off the keplerian elements from STK's website, for example.)
  2. Sapphire's downlink frequency is about 437.100 MHz (I say 'about' because the frequency has drifted as the crystal has aged, so it may be more like 437.095 MHz now).  [If anyone has an updated measurement, please let me know!]
  3. Sapphire sends a burst of carrier wave (just carrier, no data) every 15-60 seconds; it will sound like a blip or a 'hiss' depending on your radio setup.  (The period between bursts depends on mission control commands; we vary the period to do things like manage on board power and make it easier to track.)
  4. If someone is sending data to/through Sapphire, the downlink will sound more like a buzzing noise; this is 1200 baud AFSK packet (standard amateur radio TNC packets).  You are, of course, welcome to listen in on any packet traffic; the data will appear as lines of text.  (Sapphire's callsign is KE6QMD, which will appear at the start of any packets sent by him.)

Level Two:  APRS digipeating

Sapphire's main operational function today is as an APRS digipeater; I refer you to www.aprs.org for much more information on APRS.  Anyone is welcome to use Sapphire's APRS function (I refer you to http://web.usna.navy.mil/~bruninga/pcsat.html for a detailed discussion of digitpeating through spacecraft and the user service agreement that covers both PCSat and Sapphire is: http://web.usna.navy.mil/~bruninga/pcsat/contract.txt).

If you do try to repeat packets through Sapphire, you need to send them up at 145.945 MHz and listen in on 437.100.

Level Three:  Actual contact

Sapphire acts as a bulletin board system, and users "log in" to the system (which behaves similarly to an old UNIX text interface).  If the 'guest' password works (see below), then you are free to take data and download files (type 'help' or simply 'h' for a list of commands).

The process is:

  1. Configure your station:  145.945 up, 437.100 down, 1200 baud, 8 bits, 1 stop bit, no parity bit (1200 N81), AFSK modulation, standard amateur radio packet protocol.
  2. When Sapphire is in range, attempt to connect ["connect KE6QMD"]
  3. If successful, you will get the "*** CONNECTED to KE6QMD" followed by a passcode and a request for your password.
  4. Enter guest as the password.
  5. Sapphire has two basic operational modes, one which allows guests and the other which does not.  If the (default) no-guest mode is active, you will be disconnected.  If the guest-allowed mode is active, you will be logged in to the system.

Level Four:  Command & control

If you get all the way through Level Three, contact me again.  We can find interesting things for you to do.

Commands to Send After a Reset

Assuming that whatever caused the reset has been resolved, these are the commands needed to restore Sapphire to full operations.  The first few commands set the clock, beacon and allow multiple users.  The table commands set up a crude timer to reset the TNC after a given amount of time.

  1. os time [current GMT in this format:  hh:mm:ss mm/dd/yyyy]
  2. os users capacity 5
  3. os beacon period 30
  4. os beacon message 00
  5. os beacon go
  6. sensor table stop
  7. sensor table create 0  0 -    0 1 1
  8. sensor table create 1  0 -    0 1 "quickset 32 step 1"
  9. sensor table create 1 32 - 8600 1 "os users broadcast 'TNC must be power-cycled; you will be disconnected'"
  10. sensor table create 1 32 - 8600 1 "os pins cycle 16"
  11. sensor table create 1 32 - 8600 1 "quickset 32 0"
  12. sensor table go

File Management

Updated 04/10/2002 10:30 (CDT)

Download these files:

(in order of importance)

Any new file.

Ignore these files:

 

 

Operations Plan

Updated 2/19/2002 1113 (CST)

 Current tasks include:

Vehicle Performance

Our primary operational task is to gather enough data to characterize vehicle behavior.  This consists of commanding sensor file captures and then downloading them.  The first thing to do on every pass is to log in and check status:
  1. os time
  2. sensor view 0-33
  3. os files list
  4. os error list
Next, these commands should be executed:
  1. sensor acquire 0-31 1 1                    [vehicle snapshot]
  2. sensor acquire 0-7,10-15 1 180    [attitude/pointing/power snapshot]
  3. sensor list   [to find the names of the above-generated files]
  4. sensor get [filename]
[Remember that the commands are space-sensitive - don't put any spaces in the sensor list or the command will not execute correctly.]

These commands can be executed during the contact or scheduled for a later time (os scheduler add relative [hh:mm:ss] sensor acquire ...)

Camera Performance

Our second operational task is to characterize the camera performance.  This consists of letting the camera heat up, then snap pictures and then to download them.  Students are developing a set of table commands to do this.  Here is the working script:

s t c 0 32       -     1   1    1
s t c 0 24    2320     -   1    "o p s 2 1"
s t c 1 33       -     1   1    "quickset 33 0"
s t c 1 14       -   2900  1    "quickset 33 step 1"
s t c 1  1     150   -     1    "quickset 33 step 1"
s t c 1  2     150   -     1    "quickset 33 step 1"
s t c 1  6     150   -     1    "quickset 33 step 1"
s t c 1  7     150   -     1    "quickset 33 step 1"
s t c 1 10     180   -     1    "quickset 33 step 1"
s t c 1 11     180   -     1    "quickset 33 step 1"
s t c 1 33       -   7     1    "s a 0-31 1 1; c a; s a 0-31 1 1"
s t c 1 33       -   7     1    "s a 0-31 1 1; c a; s a 0-31 1 1"
s t c 1 33       -   7     1    "s a 0-31 1 1; c a; s a 0-31 1 1"
s t c 1 33       -   7     1    "quickset 32 0"

THD Performance

Until Sapphire resumes spinning, THD data must be scheduled for specific events:  crossing from eclipse into daylight (or vice versa) and during the flips Sapphire makes near the North/South poles.  For either event:
  1. os pins set 0 1
  2. os scheduler add absolute [hh:mm:ss mm/dd/yyyy] sensor acquire 1,2,10,11,14,20-23 20 30
  3. [repeat at 30-second intervals for 2-3 intervals]
  4. os scheduler add absolute [time + 5 minutes] sensor acquire 0-31 1 1
  5. os scheduler add absolute [time + 5 minutes] os pins set 0 0
  6. os scheduler list

Old Operations Activities

"Go Navy!" Voice Message

This week is Army/Navy week, culminating in the Army/Navy game on Saturday.  Since Sapphire is a USNA vehicle, he will be voicing his support.  Nominal plans call for 10 repeats [max allowed] every 120 seconds.  The trick is to identify the passes where Sapphire flies over USNA (Annapolis, MD).  Choose the scheduled time according to the start of the pass.
  1. voice speak 10 20 "Go Navy!  Beat army!" [use this to test the command syntax and voice clarity]
  2. os schedule add absolute [hh:mm:ss mm/dd/yyyy] voice speak 10 120 "Go Navy!  Beat army!"
  3. [repeat for all predicted passes]
  4. os schedule list

OSCAR/Marconi Anniversary Messages

From 12/5 through 12/12, Sapphire broadcast two voice messages in celebration of the 100th anniversary of Marconi's first transatlantic radio broadcast and the 40th anniversary of OSCAR-1, the first amateur radio satellite. This was also the first time the on-board table system was used for controlling the spacecraft in flight.

These tables are set up to repeat two messages every 24 cycles (just over two minutes).

  1. sensor table create 0  0 -  0 1 "quickset 32 step 1"
  2. sensor table create 0 32 - 24 1 "voice speak "thank you, mr. mar kol knee!  from sapphire""
  3. sensor table create 0 32 - 24 1 "quickset 32 0"
  4. sensor table create 0  0 -  0 1 "quickset 33 step 1"
  5. sensor table create 0 33 - 24 1 "voice speak "happy birthday oscar 1,, happy birthday to you!""
  6. sensor table create 0 33 - 24 1 "quickset 33 0"
  7. os schedule list