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Seaglider One-Pager

Quick-reference notes for common Seaglider basestation and piloting operations. This page grows over time — add notes as new important reminders are identified.

Source

Paraphrased from the APL-UW IOP Basestation3 and seaglider.pub Best Practices note, the Extended PicoDOS Reference Manual, the Seaglider Piloting Parameters guide, IOP PLOCAN training material, and pilot working notes. Always confirm against the Parameter Reference Manual and defer to APL-UW IOP documentation.

Basestation Shortcuts

Command What it does
gcd sgXXX Jump straight to glider sgXXX's current mission directory.
basepy <script>.py --help Run a basestation3 script with the correct interpreter (/opt/basestation/bin/python3) without typing the full paths.
tail -f comm.log Watch a glider's call-in log live as it happens.

Starting and Ending a Mission Cleanly

Use NewMission.py / MoveData.py for every mission

basepy NewMission.py . MyMissionName before a mission sets up the mission directory (copies in sg_calib_constants.m, symlinks pagers.yml, and points current at it) so the glider and pilot are both working from the right place. basepy MoveData.py -m . -t ArchiveName after a mission files everything away. Skipping either one is the easiest way to end up with stray files and a messy basestation before the next mission.

Editing missions.yml Without Breaking vis

  1. Copy it: cp missions.yml ~/missions.new
  2. Edit the copy.
  3. Test it: basepy vis.py -r ./ -f ~/missions.new -t
  4. Only if that comes back clean: cp ~/missions.new missions.yml

Simulating an Incoming Call

Test the basestation without waiting for the glider to phone home

Logging into a glider's dedicated basestation user account and exiting (su - sgXXX then exit) re-runs the same call-processing pipeline a real Iridium call triggers — handy for testing basestation-side scripts or plotting changes on demand.

PicoDOS Batch Commands

Useful pdoscmds.bat / interactive PicoDOS commands beyond the basics covered on the Dive Cycle & Control Files page:

Command What it does
target NAME / targets NAME RADIUS Switch the glider's current target (and optionally its radius) without editing the full targets/mission file.
resend_dive /d 289 1 Resend one 4 kB chunk of dive 289's data file (/l log, /c capture, or drop the chunk number to resend the whole file).
xr FILE / xs FILE (also get / put) Receive (xr/get) or send (xs/put) a file over XMODEM.
ren OLD NEW / del FILE Rename or delete a file on the CF card.
strip1a FILE Strip trailing XMODEM padding — required on anything transferred to the glider over XMODEM.
tar c ARCHIVE.tar FILES / tar x ARCHIVE.tar Bundle or unpack files on the CF card, e.g. before pulling a batch off.
menu /path/to/command args Run any command from the glider's menu tree by absolute path.

Swapping a sensor's .cnf file via a batch

ren pam.cnf pambad.cnf
del pam.cnf
xr pam.cnf
strip1a pam.cnf
menu param/config init=1
Rename the old config out of the way, receive the replacement over XMODEM, strip the padding, then reinitialize the sensor's config menu so it picks up the new file.

Loitering / Subsurface (Park) Dives

Two different things both get called "loitering":

Picking a depth to sit at. Look at the T/S and density (SigmaT) casts to find a stable density surface at the target depth. As a rule of thumb, about 1 SigmaT unit ≈ 50 cc of buoyancy adjustment, and 1 cc ≈ 4 AD counts of VBD travel — useful for estimating how far to offset the VBD to sit neutrally buoyant there.

Making the glider actually stay there. $T_LOITER holds the glider at apogee (neutral buoyancy, zero vertical velocity) for that many seconds before it pitches up to climb. While loitering the glider will pump but never bleed, and it does not servo on depth. Remember to extend $T_MISSION / $T_ABORT manually to cover $T_DIVE + $T_LOITER, or the mission timeout will cut the loiter short.

Subsurface finishes and comms can miss each other

$D_FINISH / $D_SURF / $N_NOSURFACE let a dive finish at depth instead of the surface ($D_FINISH must be ≥ $D_SURF, or the glider always surfaces normally). If you combine this with $CALL_NDIVES > 1, make sure the dives on which the glider actually calls line up with a real surface finish — otherwise you won't hear from the glider again until $N_DIVES or a low-battery recovery trigger.

Bumping the Baud Rate for Fast File Transfers

Loading a new main.run or other large file over the serial/XMODEM link at the default rate is slow. From PicoDOS:

PicoDOS> baud 38400

Change the terminal program's serial port setting to match, run the transfer, then set it back to the default (9600) afterward — the glider and terminal must agree on baud rate to talk at all, and leaving it changed will strand the next session.