19 observations in 6 expeditions
Expeditions Contributed to
This is a very late post (like 2 years late). On another trip to this lake another survey was done. After spending time searching, the tether came into sight and we were able to trace that to the ROV. This video is the story of the entire search and recovery effort!
The third dive of the day was completed using Brian’s ROV. This ROV is an OpenROV v2.8 and has external lights as well as a neutrally buoyant tether.
Jaime conducted the first dive with his custom ROV (which utilizes the OpenROV electronics, software, and external lights). Manyu conducted the second dive with his OpenROV v2.6.
We did a little bit of research using Google Maps to get an idea of where we were going. Once we had everything packed up we just went for it!
The three dives were all successful. Visibility was extremely limited and without the external lights this mission would have been nearly impossible past about 1m of depth. There was one small entanglement issue when the ROV was left un-piloted momentarily and the current swept it into the pilings. Since visibility was so bad it was impossible to see where the tangle was. After some effort the ROV was able to break free and drive to shore. The tangle was still wrapped around the pole. The tether was disconnected from the ROV (thank goodness for quick disconnects) and then pulled back around to untangle it. Overall the expedition was a success with everyone having a good time and the robots seeing some interesting things. We are all looking forward to next months Monthly Expedition Day!
After doing some brainstorming of places to go for the Monthly Expedition Day we settled on doing some exploring around the Fruitvale Bridge to see what is around there. We wanted to see is there was any life and if we could find anything interesting.
We went back to the drain pipe with an OpenROV v2.8 with an external light and neutrally buoyant tether to investigate even more of the pipe.
Ultimately we did not end up finding the ROV. The dock that it was tied to was removed and we are guessing it was either dragged to a different part of the lake, or the tether snapped and we need to search the exact spot the ROV was tangled. I hope to go back sometime this summer and continue the search. We are also going to follow up on a lead with the person who removed the dock.
ROVs packed up and ready to rescue their lost friend. Time to drive from North Lake Tahoe to South Lake Tahoe.
On August 3, 2014 OpenROV #589 was left of the bottom of Fallen Leaf Lake. It was being used to inspect some chains that were holding a dock to the shore. The tether was tangled in fallen trees, resulting in the ROV being stuck on the bottom. The decision was made to leave it there and conduct a long term test of the ROV at depth. It has now been 9 months and it is time to retrieve the ROV and see what state it is in. Follow along to learn the state of the little lonely robot.
The production team from OpenROV made the trip to rescue this ROV since we were in Tahoe for the weekend testing other various systems. We set up a version 2.7 ROV and deployed it from a dock.
After 2.5 hours of searching we found the SS Tahoe. The bow was sitting in water that was 112 meters deep. If you watch the last 40 minutes of the video below you can see the ship.
We will be using two ROVs to attempt to find and explore the SS Tahoe. You can watch the live stream of our attempt.
After bringing the ROV up from a depth of 93 meters (over 300 ft) we believe we have determined the cause of the failure. The endcaps on this ROV are similar to the traditional endcaps but there is one layer that is aluminum instead of plastic. As the ROV descended and the pressure increased, these layers delaminated (seen on the right side of the image) causing water to flood into the electronics tube. We believe that this happened at a depth of just over 50 meters after analyzing the video and the rate of decent. With the endcaps failed, there was a tremendous amount of pressure on the electronics chassis and the shock of hitting the bottom of the lake caused the chassis, including the electronics board, to snap (as seen in the middle of the image). Once the electronics board snapped communication with the ROV was lost.