Developed by Teledyne Webb. A very professional and robust hardware especially in the last G3 generation thanks to the number of units they have sold dominating the USA market and having time to perfect the design but kind of unnecessarily complicated and not at all flexible on the software side, at least from my perspective. It's also a hassle to integrate your own sensors on them, however the new Back Seat Driver feature, has made this easier at least on the software side. If you are operating in a coastal environment with strong currents, their shallow glider with a thruster is a great option!
Their new glider is called Sentinel and it's massive! No longer two person operable but with a great endurance and payload capabilities.
Apple of the glider world, great product with a sleek user interface. Developed by Alseamar a massive French company in Subsea domain many years after the original three gliders so they had plenty of time to learn from them. They are a major part of glider competition because they have quite a strong marketing strategy and provide quite a good cutomer service. Although this is a great product, I feel since they are simply after selling more units and dominating the glider market, their claims are usually over-exaggerated or what they brag about, is either not as good as it sounds or already done by other glider teams. Either way, if you want a glider that is very simple to use with minimal training then go for this one. But beware that you will be sucked into their echo-system. Unless you buy a Seaexplorer directly from them, you will likely not be able to touch or work with one of their units, therefore most of the information presented here is based on Seaglider and Slocum which I have personally worked with.
An interesting fact about their design is that apparently the short wings make it possible for these to be launched from torpedo tubes!
Developed by APL at University of Washington and ever since the development, their team has been the major user with largest fleet of Seagliders. All the development is still happening at the UW. They have been prioritizing good quality of scientific data with an outstanding efficiency. They used to say "half a knot on half a Watt", and as a long time user I can testify to that. From my experience with other gliders and from the numbers I have seen, I doubt any other glider can come anywhere close to that. An example of how efficiency was one of their main design goals, is the signature isopycnal hull they use. The idea is that this design has the same compressability factor as the sea water and therefore the glider will keep the same density difference with water as it descends or ascends and therefore there is no need for any buoyancy adjustments to maintain a constant vertical speed. This makes the design 10% more efficient than a simple cylindrical design. But perhaps the most important advantage of Seagliders over the other ones, at least for me, was that the software is very robust and very well written and that it allows users to integrate quite complex sensors, simply by writing a short driver file for them. What Seaglider lacked and still lacks today is a proper business behind them to develop and market it properly but that was never their goal in the first place. If you need a reliable deep glider with great performance, and you want to get nerdy with your glider operation, then go for this option!
They have just recently released a new version of their glider called sgx which is supposed to be even better!
Nortek which is a dominant player in ADCP market basically felt like they have pushed ADCPs as far as they could and afraid of loosing their bright engineers out of boredom, decided to start something totally new! building gliders! They seem to be focusing on basic physical oceanography and passive acoustic so far. Small form factor gliders so ideal for some swarm action! They have an interesting design where they flip 180 degrees and climb upside down to invert the lift vector and maintain a constant glide angle. Their glider is smaller and therefore much cheapter than the other three.
A glider developed by Tianjin University in China. While everyone in the glider community trying to create a reliable deep glider that can at least dive down to 2000m, these guys have recently made a glider to reach the Mariana trench and went down to 10000m just because they couldn't aim it exactly to the trench from what I gathered, which is pretty impressive!
Developed jointly by Scripps and WHOI. One of the original three which was not commercialized. But recently the licence has been given to MRV-Systems who have commercialized it under Spray2 with some modifications. One major modification is that the pressure hull is much larger than other gliders, something similar to Sentinel glider under development by Teledyne. An interesting design of Spray is that its antenna is situated in its wing, so at surface it rolls to one side to stick its wing out of the water and initiate a call, which is cute!
The new version of this glider is called Spray2 which is similar to Sentinel glider in terms of size and it's being commercialized by MRV.
