Tulum - Day 1 (Report from the field)


Colin just sent us a report from his first day exploring cenotes in Tulum. Here are a few pictures of how he packed for his trip:

And an OpenROV in the field:

Colin in the cave:

Successful @OpenROV deployment at Cenote Naval. Man is it beautiful down there :D pic.twitter.com/6OKUy1j5o9

— Colin Ho (@ohcolinho) August 17, 2013

Here are the rest of the photos from the day. Here's the full report from Day 1:

8/13/2013 - Monkey Cave

Destination - large dry largely unexplored cenote/cave, pool about 150m into cave. possible entrace into underwater cave system. Cave also houses Maya ruins (beautiful intact altar with carving of a monkey, as well as pots), Robby discovered the spot about year ago, we came back to actually document the site and take pictures (gigapan), as well as see if the rear pool in the cave was an entrance into a greater underwater cave system.


Colin Ho (me), Fabio Amador (Nat Geo), Bil Phillips (speleotech), Robbie Schmittner (Xibalba dive)

Bil is walking cave diving history. he has mapped out hundreds of kilometers of underwater caves, and has been doing it since the beginning (for over 30 years); wise, knowledgable, always prepared and very methodical. And hilarious

Robbie is another amazing diver, has been doing cave exploration for 20 years. He is a maverick, going forward with gusto and often not as much regard for safety as he should. But he makes great discoveries and has the luck to stay alive :P. He and Bil together make an excellent team that balances both ways

Fabio Amador is a Nat Geo program manager, but is also a Archaeologist and visual communicator (photographer). He takes amazing underwater photos. He is the one that made this trip possible! :D

Traveling to:

Off-roading for few kilometers into the jungle. Final stetch of road was made a longgg time ago - pretty much over grown (was a few intances where we had to get out and chop away with machetes)

approx 1km hiking into jungle- hot, buggy, thorny, and jungly. We didn’t have a GPS location of the site, but Robbie knew the way. Initially Robbie and Bil couldn’t find the entrance after an hour or so of poking around where Robbie thought it was, and we had almost given up hope of finding it. Robbie went out one last time down the mesura (the barely cut rough trail that marks the boundaries of peoples large jungle properties), and sure enough with his luck, he found it again! (he almost missed the entrance, he just so happened to pass by it on his return search pass.

Brought single ROV (#240), laptop, and no spares. Strapped ROV to back of backpack by using front cross bar as a clip in, worked perfectly. New shell polyproelene shell is resilient to dense underbrush smacking it. Noticed that after hiking in, the internal structure slipped out of the shell; it had to be snapped back in place. ROV also took quite a beating going into the jungle, really rough off-roading, bumping, shaking and jittering.

First deployment:

  • deployed in back of cave pool; 7m away from edge of shallow pool to where it gets deeper. Deployed on top of a calcite pile that just so happened to form in the shallow pool. Perfect flat deployment spot

  • made two trips back and forth. The first only about 10m into the cave (had to come back and give it more tether and double check for leaks) and the second 20m.

  • was able to deploy ROV 20m into the cave. Far enough to be clear out of sight, and no light visible from ROV lights.

  • Determined that the cave pool might be worth exploring, couldn’t see the end of it.

  • Almost wrapped around a salagmite/tite column. was able to follow tether around the right way to get back.

  • On the way back, was able to follow negatively buoyant tether back. The bottom of the underwater cave was steeply sloped and mostly free from salagmites.

  • was mostly neutrally buoyant. slightly positive, but diving down was pretty easy

  • Noticed a little bit of fogging at the end - forgot to place descciant package in tube in the morning - (note - actually the tube was slightly leaking)

First deployment notes:

  • tether management system still iffy - sometimes pulling on it makes a whole crap ton of tether come out tangled-ish. But much better than before. You pretty much have to stop driving and purely feed out some tether. Can’t do simultaneously

  • camera tilt was absolutely necessary in order to avoid smashing into bottom/top of cave, as well as figuring out how to get around salagtites/salagmites without ensnaring tether

  • scaling lasers are absolutely critical to not bump into things. in underwater caves there isn’t really any way to easily judge scale and how close you are to objects, since visibility is so good, and

  • video stream screwed up; was not able to successfully capture video stream in VLC (files are corrupt?) - after debug tonight, seems to have found way of validating if video stream is successfully recording

  • e-tube slightly leaked - very little amount of water, just enough to fog up tube.

  • Great first dive! IT WORKSSSSS AND I GOT IT BACK

  • also, CAVES ARE BEAUTIFUL. its an alien world

  • ALSO - I found a fully intact Mayan pot! you can still see the glaze on it! it was in the dry cave and I just so happened

Post Deployment Notes:

After trip back, back at Speleotech, Booted up ROV to calibrate lasers and check fogging issue.

  • booted once and connected, and then stopped connecting

  • noticed that network comm lights would not come on.

    During reassembly, usb cable from camera moved and added a little more friction to the camera arm. Ended up stripping servo. replaced servo; still very very hairy. Maybe get metal teeth servo/servo saver in the future?

    • traced connection through everything - even with direct ethernet connection to laptop did not turn on

    • solution was to just swap beaglebone out - transferred modified JS code over to backup BB

    • Open issues - still not sure why that beaglebone network comm crapped out

  • Calcite from the underwater cave totally craps out o-rings (like sand), ended up replacing o-rings.

Index: Amazing ROV Photos

That is absolutely incredible.


Wow how exciting to be able to explore areas like this and use this kind of technology. Can't wait to see your videos when you return.


Those pictures are great and I love your kit bag. Very cool to see the rov getting used in the jungle.



This stories thrills me!

I am eager to hear about day 2!