1. Ocean Observing with
Slocum Gliders

2. What is an AUV/glider? Autonomous Underwater Vehicle
Remotely controlled through satellites (Iridium)
Connection available when glider is at the surface
Sampling devices
CTD (standard)
Optics
Chlorophyll
Turbidity
Light penetration

3. Antenna (Iridium, Freewave, GPS & Argos)
Buoyancy Pump
Science Payload Bay
Control Board
Pitch Motor
Air Bladder
Rudder
Altimeter
CTD
Fore Hull
Aft Hull
Cowling

4. How gliders “fly”
Buoyancy pump in  the glider pulls in 0.5 L of water
When surfacing to connect glider inflates air bladder
Sink downward on an angle
one dive and one climb is called a ‘yo’
Push pump out  glider inflects and floats upward on an angle

5. The Brains – turning glider on
We have a sealed up glider and a computer, now what?
GliderDOS & PICODOS
Analogy: Windows vs MSDOS
How do we talk to glider?
Use a serial interface (like USB but much older)
Freewave and/or Iridium (in tail)
Terminal Software
Procomm, ZOC, minicom, etc (freewave)
Dockserver (freewave or iridium)

6. Glider Rules, do’s and don’ts
Never run a glider open
Never turn glider on without an internal vacuum, if not sure remove vacuum plug and re-seal
Vacuum should be set to 6 in Hg on a shallow glider, 7 in Hg on a deep glider – higher is safer…
You can test your freewave and comms prior to turning on! (little black button back of FW)
Glider communication rate N1
N1 (freewave modem)

7. Glider ‘Operating Modes’
MISSION
Science sampling & data logging
Surfacing interval
Reasons for mission abort
Swimming/Glide Profile
Waypoints/navigation
Glider in water or lab
(2 operating ‘modes’)
GLIDERDOS
We can also sample, transfer data, etc
Need to set up the glider to drift or else it will try to swim!
Ballasting, lab work, etc

8. Command & Control
Power on default glider behavior: (it tries to surface and take action)
Max buoyancy & turns on air bladder
Establish communications
Sequences missions (initial.mi and lastgasp.mi)
Our Goals
Note any errors upon startup
Wait until scroll slows and then try to break out of sequence with CTRL^C
Make sure we are at a prompt
Turn off air pump (only if in lab!)
Check internal vacuum

9. Command & Control 2 Callback xx (iridium)
What are sensors, how do we interface with them
Masterdata
Put c_air_pump 0
Get m_vacuum
Lab_mode on
Neuters safety timer 10 minutes (u_max_time_in_gliderdos)
Loadmission lowpow.mi (lab only!!)

10. Common commands help Where Use Consci Zero_ocean_pressure Send Zs
Dockzr Zr
Exit
Exit reset
Run
sequence

11. Sensors and Autoexec.mi
Masterdata
Glider encylopedia
Stores all default information for missions and sensors!
Sensors U_
Sci_ C_ M_
Mission defaults and constructs/definitions
Great to use for piloting and data handling!
AUTOEXEC.mi
Gliders identity file
Longterm.dat

12. Opening & Closing glider
Take your time
Be clean and thorough
Glider is delicate (aluminum) never over-tighten anything. If anything is tighter than finger-snug, something may be wrong
Every glider is a little different
For the most part make all electrical connections
Take a picture before you seal it
Make a checklist (if need to) of things you un-plugged and then re-plug back in
Glider may not correct missing connections!

13. Glider Ballasting (prep glider)
Make sure well sealed glider
Make sure all parts present
Check vacuum again
Ballast
puts pump at 0 cc
puts battery at 0 in
Loadmission lowpow.mi (lab only!!)
Before placing in tank, check vacuum again
Ballast, yes again

14. Glider Ballasting D = M / V 1 density unit is 1 sigma BUOYANCY!
D is in units of kg / m^3 or g / ml
1 density unit is 1 sigma
1 kg/m^3
.001 g / ml
Typical densities = 1025 kg / m^3 or g / ml
BUOYANCY!
B = Vg * Dw
Sea Water equation of state (Density from conductivity and temperature, and depth)

15. Glider Ballasting Pump size is ~ 400 mL (+- 200 mL)
We operate from neutral, 0 ml (ballast)
Maximum range of 50 kg / (50 + pump) L
+- 4 sigma, use +-3 for safety margin
Maximum range is 6 sigma units!
We need help to improve range, how do we do it?
We shrink a little at depth (V decreases, D increases) so we can get a bit deeper (this is the only way its possible for a 1 km glider to get deep!)
Ballasting considerations (in priority order)
Lowest surface density (for entire deployment!)
Coldest surface water
Densest deep water

16. Deep Glider Example

17. How a deployment works MISSION Science sampling & data logging
Surfacing interval
Reasons for mission abort
Swimming/Glide Profile
Waypoints/navigation
Glider in water or lab
(2 operating ‘modes’)
GLIDERDOS
We can also sample, transfer data, etc
Need to set up the glider to drift or else it will try to swim!
Ballasting, lab work, etc

18. Missions Missions are: What is a behavior
Prioritized
List of Behaviors
Defined by behavior arguments
What is a behavior
Glider is capable of a dozen or so behaviors
Sampling, surfacing, diving, climbing, navigating, hovering, etc
Behavior arguments
Define start and end of behavior
Define how deep we dive, climb, or when we surface
Why does priority of behaviors matter?
Aborts and shared behaviors
Missions are mostly static, define your missions, verify they work and stick with them. Often a mission skeleton can be used across gliders

19. Missions & MAFiles MAfiles make a mission flexible and changeable
Goto Yo
Sample
Can’t edit a file on glider, thus we use MAfiles (snippets of a mission file)
Missions can also be used for sensor value setting, like put, but for many sensors: for instance lowpow.mi

20. Glider Data Files Uses of each type of file
2 computer, Glider and Science
Each computer generates 4 filetypes of similar construct
D(inkum)BD – EBD
M(edium)BD – NBD
S(mall)BD – TBD
MLG – NLG
Uses of each type of file
Decoding into Matlab or ASCII

21. How a deployment works
‘Dockserver’ (Remote glider access and control, scripts) (Glider terminal)
Iridium modem (SBD, SURFACE DIALOGS, RE-TASKING)
Glider deployed
Data websites
‘Ironman’ (Rutgers computing server and fileserver) (data parsed and plotted in MATLAB) (automatic file syncronization between dockserver and IMCS fileserver)
Google Earth piloting and display
monitoring, diagnostic pages, alerts and broadcasts

22. Piloting Surface logs, websites Google Earth
Plots you should have to pilot
WINSCP, SSH access
KML to goto
Decoding, plotting
Any other questions?