Farewell for now from Cal Poly!

It feels like this month has gone by so quickly! But either way, the time came for us to bid adieu to the Maltese Islands. From interesting cisterns, to collaboration with Harvey Mudd; from interesting cultural tours, to once-in-a-lifetime opportunities; this experience was unforgettable for each and every one of us. Just to name a few of the highlights were Timmy's never-ending knowledge of the Maltese Islands, Davide's tours of the Siracusa area, and the wealth of intriguing talks at our apartments, on topics including the Maltese language, Maltese politics, robotics control systems, subterranean Valletta, ancient water systems, and cultural heritage management.

Although our Mediterranean excursion has come to an end, we certainly have more work ahead of us, with the conclusion of our individual research projects, and quite a bit of data processing as a team. Thank you to all of our collaborators, supporters, suppliers, and followers, and stay tuned for progress and wrap-ups on our projects!

Aerial view of Gozo from our Air Malta flight

Stateside welcome upon entering customs at LAX

Late night view of the San Luis Obispo airport upon returning

Malta vs. Italy FIFA World Cup Qualifying Match

The ICEX team outside the stadium

While we were back in the U.S. the whole team did some research on cultural things we could do while we were in Malta. During our researching, Andrew discovered that Malta and Italy were going to play a FIFA World Cup Qualifying Match during our stay and we could not pass this great opportunity. On Tuesday night, after mapping the St George Bay cave, the time finally arrived
and the whole team was super excited for the match. Even though Malta did not win, the cheering crowd was not affected by the overall score. We even got to do the Mexican wave!

Ian and Amanda cheering for Malta

Fans forming the Maltese flag

Jeff, Andrew, and Erik entering the stadium

St. George's Cave

On Monday and Tuesday we visited St. George’s Cave. When we arrived at the cave, we discovered that the water level had risen significantly since the last deployment 2 years ago. The land bridge that had previously connected a large rock hill was approximately 1 foot underwater, so we were forced to setup our control box and other equipment outside of the cave.

Rock hill on the right

More of the cave...Pictures just don't do it justice in scale

We quickly deployed with the Smart Tether and began taking sonar scans.  It took a couple of hours just to map the outer walls of the cave, and it was lunchtime before we knew it.

After lunch, we redeployed with the HOBO sensor. When we went to put the ROV in the water, we noticed that the water level had risen since the morning. This made us wonder if the cave is somehow connected to the sea. Our HOBO data may help us answer this question.

Andrew on tether

Tape for our "Slices of Pie"

We quickly ran into a number of Smart Tether issues. After about an hour of troubleshooting we decided to begin taking manual measurement by driving the VideoRay to a wall, marking the tether with tape, diving to the bottom, and marking again. We kept a log of time stamps and approximate locations in my journal, in addition to our usual log books. These timestamps will help us match up the corresponding HOBO data. We decided to call this our “Slices of Pie” method, since we were taking new readings ever few degrees around the semicircle cave.

By  By the end of the day, we had finished collecting dense HOBO data for about half of the cave. When we returned on Tuesday, we decided to continue our “Slices of Pie” method for the remaining half of the cave. Interestignly, about 1/3 of the cave was blocked from view by the rock hill mentioned above.

View from the cave entrance

I quickly volunteered to be the adventurer who would cross the submerged land bridge to assist with the measurements on this portion of the site. As soon as I had crossed the bridge, we began having some software issues, so I spent ~20 minutes alone in the dark cave. It was a little creepy at first, then quite peaceful, and then very fun, as my eyes slowly adjusted and I explored more. By the end, I felt like Gollum sitting inside a dark cave surrounded by water.

Once the ROV software was back up and running, we quickly finished our slices of pie. One of the slices had a deep channel below it. We dove about 20 meters and could not descend lower, but still saw pitch black below, indicating that it went much further!

I’m excited to see the results of this deployment. Even with our manual logging style I am hopeful that we will get some interesting results.

Mapping and Visualization Updates

Hi everyone! We've been working hard on producing maps and visualizations of some of the cisterns. I have been particularly interested in reconstructing medium sized features from stereo camera data (archways, stairs, bumps, etc.) in the Mediterranean Conference Center cistern that I made a sonar mosaic of the other day. To affix our stereo data to the rough SONAR generated models, first we have to make a map and reconstruction of the cistern.

The cistern was enormous, and our software can only support chunks of the larger models at any one time (well... before we use up 8 gigs of RAM and crash our software), so I have been working on the cistern piece by piece.

I captured some great stereo images in one of the main chambers of the cistern. From the 2D sonar mosaic the room doesn't look too interesting. However, from a 3D standpoint the chamber looks like a mushroom! Much more interesting! This is why 3D SONAR is so important to us and to our archaeologist friends.

Mediterranean Conference Center 2D Sonar Mosaic

Mediterranean Conference Center 3D Sonar Mosaic

I took the 3D sonar mosaic and converted from pixel space to 'blender space', and then from 'blender space'  to meters. I then loaded the scans into our mapping algorithm to produce a 3D occupancy grid of the SONAR data. Here is the map which we will use to construct the final 3D mesh which will be a closed surface and will look much nicer!

Mediterranean Conference Center SONAR Occupancy Grid

So far this room in the map is about halfway through our visualization pipeline. We have a couple more steps to go in order to make it a pretty 3D graphic that people can use for study and learning. I intend to fuse some of the stereo data from this cistern into the model as well. The work on that front has been a little more difficult due to the underwater image noise and poor quality of our stereo hardware, but here are a couple of preliminary disparity maps that were processed (in the method described a day or two ago) from raw underwater captures on the stereo cams.

The plan is to add some of these features back into the meshes, so stay tuned for results on the computer graphics end in the next couple of days!


Footnote: Just for fun - Vanessa just posted this, but here is a picture of me driving the robot in this very cistern (in the deep dark depths of the paint closet) to give a little bit of context.

Saturday Deployment with HMC

Last week was an exciting week with the Harvey Mudd students and faculty! We were sad they couldn't stay for longer, but were happy to have their help and expertise for the time they were here.

Working with the HMC Students

On our last day together, we went to MCC for the third time to use double sonar (vertical and horizontal scans). We were successful in using this new technique to map the cisterns in 3D. The cisterns at MCC were really complex and we are excited to have some models made by Erik and Ben! Given that we are from different campuses we had only met once before the trip, but we quickly learned how to work together efficiently and effectively! We hope to visit HMC next quarter to share our results and experiences.

Deploying the ROV (Erik, Spencer)

And, of course, our wonderful professors grading!

Zoe and Chris

Final thoughts

The Harvey Mudd ICEX team (Chris, Alistair, Joshua, Ben and I) wrapped up our trip and are now stateside. Minus a couple pieces of luggage, we made it back in the middle of the night and in time for Chris' autonomous robot navigation class.

The Maltese coastline alongside Valletta

All in all, this trip has a great experience - this includes learning about the rich history of Syracuse and Malta, having the opportunity to access private properties and catacombs to conduct research, and the chance to play the many roles needed in each deployment. To run a deployment and document our work, the team needs someone on the log books, the ROV tether, driving the ROV and collecting sonar data. Here are some great shots Zoe got from our last HMC-Cal Poly deployment in Valletta -

Vanessa and I on tether.

Driving the ROV and collecting data
during a deployment.

It wasn't hailing this time, and on these last few deployments we got some great data from 3D sonar data of some really intricate cisterns and deploying both ROVs!

Our 3D sonar set up on the ROV :)

Now that the cistern data collection has ended for us, our next steps are to map and localize the ROV using this information, and we also hope to work with younger students in Southern California to inspire the next generation of computer scientists and engineers with our work and outreach efforts.

The complete ICEX team, and our gracious dinner host.

I feel very lucky to have had the opportunity to be a part of this project. I want to thank the Cal Poly students for their work all month and getting us on board during our time in Malta/Sicily, our advisors (Jane, Zoe and Chris) for their guidance and great company, Timmy for enriching our trip by putting our work in a cultural and international context, and my teammates for pretty much everything. I wish the Cal Poly team luck in the rest of their work this coming week in Malta :)

Tentative Conclusions

I set out at the beginning of this journey with the goal of researching some of the most important natural resources to Malta. So far, I have investigated water, oil, coal, and stones. I would still like to research a number of additional resources such as wood and metals. I am also very interested in discovering what Malta does with its waste and what products it recycles. I have done a significant amount of research on this topic already but have not yet had time to write a nice summary.

A number of different research questions have become visible during my research. I highlighted some of them at the bottom of each post. For example, I am interested in researching how much water is imported into Malta in the form of food products.

I am also interested in exploring the sustainability of the current natural resource usage. I found some interesting information about limestone depletion and would like to continue researching this topic.

Even though my research is far from complete, our Maltese trip is quickly coming to a close. I am attempting to visit the University of Malta during my last week so that I can speak to some students and professors about my research topics. Specifically, I am very interested in their opinions on how a lack or abundance of certain resources has affected the development of engineering projects in Malta.