Tas Silg Temple

We had an incredible opportunity to access an archeological site restricted to the public to investigate the cisterns on site. The temple has a great deal of history... from being a pre-historic site of worship, to a Roman temple that stood as a beacon from the bay below. One interesting feature of the temple was the clay walkway that surrounded the center of the temple (only about half still in tact) that was patterned with evenly-spaced square pieces of marble. Our archeologist on site, David, said that this was a way of defining a "medium" for extremely important ground and common ground. It was a mix, making it a sort of semi-formal site. The temple was of course in ruins above ground, but was currently being excavated for further discoveries in the area. There was a full-immersion baptism site, signs of large columns to hold the roof, and clear signs of divisions within the temple.

The cisterns, however, we more intact underground than the remains above ground. The first cistern was square with 4 hallways in each direction. One was too shallow to investigate, and was even hardly noticeable, as the water level only allowed us to see the slit of the bottom of the hallway. The other three hallways led to large rooms filled with rubble. Each of these rooms had at least two off-shoots that showed signs of even more caves. Unfortunately, all of these accesses were too shallow for the ROV to pass.

The second cistern was similar, but only one hallway was deep enough to explore. This hallway was back towards the first cistern. Once we reached the end of the hallway, it was clear that this hallway connected the two. Below, you can see the mosaic of the sonar images we gathered from the cistern. As you can see, this was a very complex and exciting cistern.

We explored one more cistern out in a nearby field, but it was only a circular well with no outlets. Below is the group with our archeologist, David, at the temple site.

More Projected Geometry

Projected geometry has improved! Surface extraction for a cistern has made it through the pipeline and (as shown below) is now visualized. At the moment, we have a simple keyhole cistern... one of the most common outline shapes for cisterns. It is interesting to see how the sonar scans picked up other objects at the level of the scan that have been interpolated into vertical barriers (seen as pillars).

In addition to surface extraction, I now have multiple projections that can be merged together as a mosaic on the wall of the cistern. Below you can see the mosaic merged together in Microsoft Word on the left. On the right, the same mosaic is replicated in the 3D environment on a wall of the keyhole cistern. The images are actually taken from the ISIS boat trip. On the ISIS, we recorded the ROV's video of the shipwreck. From the video, I took screenshots that represent sequential frames of different features of the shipwreck. With a little patience, I put the images together (as accurately as I could) to represent the shipwreck.

This process will be the same for combining images from the all of the surveyed sites with their corresponding geometry. The mosaic process of projective texturing still has a lot of work to help streamline the process more. Just for the record... this is all REALLY cool :P

Underwater Roboticists Unplugged

Snorkeling Day 1

On Chris's last day we decided to be a bit more adventurous than usual. Chris really wanted to go swimming in the Mediterranean and what a better way to enjoy the beautiful weather than laying out on the beach and snorkeling for a few hours. The scenery was picturesque with clear shallow water surrounded by a bright blue sky. The best part of snorkeling was not the wildlife in the water (as there was about 2 fish that I saw) but spending a good length of time enjoying our surroundings both above and below the water. A good chunk of the time we spent in the water was laying on our backs while floating in the water, enjoying each others company, and taking everything in. It was truly a unique experience.

Exploring the Mediterranean

Postcard worthy view of the beautiful underwater landscape

Putting on the flippers!

Laying back and enjoying the view

Up-close and personal looking up at the bright blue sky

Acrobatics underwater

Enjoying the warm, clear waters of the Mediterranean.

The saying,"A picture is worth a thousand words" couldn't be more true in this picture.

Inspiring the Next Generation - Teaching Robotics

Part of the ICEX goals this year have been reaching out to elementary school aged children and introducing them to robotics and inspiring them to go into science and technology fields. During the quarter back at Cal Poly, we visited two different 2^nd grade classrooms at Pacheco elementary school every Wednesday. We switched off between the classrooms and had hands-on lessons that talked about design, testing and programming. It was very successful. The kids seemed to really enjoy it and retain a lot of what we taught. We even got a book of thank you notes written by all the students afterward – a nice touch.

Originally, that was going to be the extent of our outreach. At the suggestion of Timmy though, we packed a suitcase full of little robots so we could continue the lessons at several Maltese grade schools. We started off with a brief lecture about different types of robots and introduced the robots we brought and the paper disks used to program them.

The disks we used were small circular pieces of paper (that we had to individually cut out beforehand). The robots have two sensors that read the disk as it rotates and determines if the 2 rows of squares are black or white. Depending on the combination of black and white, the robot will go forward, stop, or turn left or right.

We then broke the students into groups of 3-4 and let them each “program” the robot to navigate a simple maze we created on the floor with tape by coloring disks with black pencils and pens. Overall, the students were very excited about it and there were several students who even inquired about where they could get their own robot so they could do more on their own.

It was encouraging to be so enthusiastically received by both the students and faculty of the schools and in addition to being a good educational experience for the students there, it was a great experience for the ICEX team as well to be able to talk with so many students (who represented a variety of ethnic backgrounds).

The Cave of Wonders

You will wish you were here! Day two of the cave had a few exciting discoveries... as well as a couple of newly created set-backs. Because our sonar was out of commission the first visit, we spent all of Thursday repairing and splicing the tether that caused the problem. Today, we finally had a chance to map the cave and the wonders contained within its depths.

The newly repaired tether worked like a charm as we mapped the surface of the first pool in the cave. We also mapped varying depths at multiple locations in the cave that we hope to "paste" together. This will hopefully be enough data to completely represent the water within the pool in the cave. In addition to horizontal scans with the sonar, we ran a couple of lengths in the pool with the sonar strapped vertically to the ROV. This will provide us with two sets of dimensions to log the depth of the pool. We used this method primarily to make up for our faulty depth sensor in the ROV's control box.

After mapping the pool, I drove the ROV around to get some close up video of the sides and bottom of the pool. I found a lot of interesting things... a couple of tires and oil bins, plenty of rubble, bottles, and occasional sections of wood. One particular piece of wood had a community of water creatures... either miniature crawdads or a type of shrimp. It was pretty cool!

Unfortunately, our repaired cable suddenly failed and we lost driving ability for the robot. We switched to our other tether, but that one didn't connect sonar, so we only did visualizations from then on.

All in all, the cave was very exciting. I only wish I had my scuba gear to dive down in it!

(More?) Hardware Repair

So we decided to stay home on Thursday (March 10th) after running into some hardware troubles on Wednesday and ended up getting a lot of troubleshooting done. Our major goals for the day were making the partial ROV water-proof so that we could check its depth sensor in our makeshift pool (a large trashcan), checking the depth sensor of the full ROV, and doing some work on one of our tethers so that we could get full communication with the ROV (one of the problems we experienced Wednesday).

Tyler and I worked with the ROV and Brig and Jeff took on the tether job. We hoped to meet up later in the day to connect the 2 hopefully-fixed pieces of hardware. Tyler and I put the trashcan into the shower and filled it up with water.

We waterproofed the partial ROV and put it in the water for the first time since we've been here in Malta (we had been primarily using it for parts). We used both ROVs and both of our control boxes to test the depth sensors. We received inconsistent readings of depth on the control boxes, and could not communicate with the sonar unit at all. After some testing, we took a break and got some McDonald's coffee down the road. We were even graced by Timmy's presence midway through our day.

Jeff came down and finished up splicing the new piece of the tether together so that we could combine our jobs from the day.

The fixed tether solved the sonar communication problem completely! We now knew that the problem was in the other tether (the one not spliced) so we could now actually get sonar data from the cave! We also tested both cables connected in tandem so that we might be able to get some extra length in the huge cave. The cables connected and were able to control the ROV, but we still did not have sonar communication, which again assured us that the error was within the tether.

The final step was to waterproof the new connection. This required wrapping each connection in electrical tape to prevent shorts, sealing all the connections with epoxy, heat shrinking the epoxy, covering this in a sturdy hose-like wrap, and finally epoxying the ends of the cover.

By the end of the day, the ROVs were back together and waterproofed, and the tether could now communicate with the sonar. Although we lost a day at the cave, we were able to successfully remedy some major problems, and the entire team felt like it was a good choice.

Gozo

In addition to collecting information at various sites throughout Malta, we’ve been able to go to several sites on the smaller island of Gozo. Gozo is only 14km long and 7km wide and has approximately 31,000 residents. It is known as being much more green compared to Malta and the industry is more focused around agriculture. Below is a view over part of the island, as seen from the citadel in Victoria (also called Rabat) which is the capital city of Gozo.

Our sites on Gozo (on Monday) were focused on water galleries (as opposed to cisterns or wells). It was a neat change of pace to see the lay out horizontally instead of relying completely on sonar and video data from the ROV to get an idea of the layout and general structure of the cistern.

We did two sites on Monday. The first one, Ghar Ilma (Water Cave), was at a private residence and was apparently very important in supplying most of the water for the citadel back when residents of Gozo would have to sleep within the protected walls of the citadel (to stay safe from pirate attacks). I was surprised at the extent of this gallery. There were several different passageways and the main one extended for over 900 ft. We collected data for a lot of it, but were unable to map everything due to the limited length of our cable (only 250 ft) and the fact that there was a pile of debris blocking part of the main passageway.

Our second site was another private residence in someone’s garden. We set up in a small grove of tangerine/orange trees and ran the cable down to the water gallery. The depth readings on our control box were still not working properly, but we were able to get good sonar scans for the entire gallery.

After we finished collecting data, we packed up quickly and drove to the ferry in order to catch it on time (so we could meet our driver on the other side at the scheduled time). We got there in time, but almost missed the ferry anyways due to complications getting all of our equipment (a large generator, several large robot boxes, and various other bags and toolboxes) into a luggage container. We did end up making it, enjoyed the beautiful ride back to Malta and concluded another successful day of data collection.

Projective Texturing of Cisterns

For the final presentation of the cistern exploration project, all of the video and images will be mapped to the geometry generated from the sonar data. The screenshot below is a mock world generated to serve as example data extracted from sonar. Using mathematical calculations, the images are loaded into a program and projected onto the geometry (just like you would think a projector to work) to make the world look more realistic and similar to what it actually looked like from the perspective of the robot. There is currently only one projection of one image taken of a cistern a couple of years ago.

At this point, there is certainly more work to be done to merge our actual data and images together. The previous plan was to automate the video frame extraction with the location and orientation of the robot and project it. After completing many projects, we realized that it would be near impossible to complete this automatically and accurately.

Currently, my plan is to (once the geometry is loaded into the program) load images that correspond to the cistern and scan through them until one matches the current orientation within the world. At this point, the image projection will be saved, and a new image can be loaded to project and save to overlay or stitch with previous projections. This method will be an easy way to accurately bring multiple images together and place them in the right place in the geometry to make the world realistic.

The Cave

Today (Wednesday) we began exploring a cave at St. George's Bay in St. Julian's. It was huge! It is this large, deep pool of water contained completely in this cave. We had a bit of a trek to get to the entrance, and when we got there, we had to walk down a staircase which led to the water. We set up our equipment up near the entrance so we had some light to work in, and Andy and Brig practiced their driving skills for the first time since we've been here in Malta.

Unfortunately, like yesterday, we had a lot of technical problems with the sonar communication (a relatively new problem since Chris showed up...impeccable timing). We ended up deciding to not dedicate too much time initially to troubleshooting the problem, and get on with exploring the cave. We took a lot of video and really just wanted to get a feel for the size and environment of the cave. With 3 days to explore, we wanted the first day to be dedicated to getting a grasp on the cave as a whole.

Around lunchtime, we decided to pull the ROV out, and attempt to do some debugging on the sonar connection. We narrowed the problem down to the actual connection between the ROV and the tether, but were not able to come up with a solution on site.

Deciding to continue with just video, we put the ROV back in the water and I took control of the control box for awhile. My goal was to get as deep into the cave as possible, given the limited amount of cable we had.

After exploring for awhile, I hit a maximum depth of about 35 meters (114 feet!). I went into the cave as far as I could, and when I was pretty sure I had run out of cable, we decided to turn around. Upon trying to surface, I realized that there was a bit of a problem: I had created some significant snags in the tether while driving around. This was probably one of the worst tangles that the ROV had experienced thus far, according Chris, so as one could guess, there was a bit of stress around the cave site. Half of the team was down in the cave, waiting to wrap up the cable as it became untangled, while the other half watched the video feed and attempted to strategize a plan to untangle the ROV. Chris ran back and forth between the computer and the cave to try and quickly solve the problem so we didn't end up becoming completely stuck in this massive cave. It took quite awhile to remedy, but after some careful driving, we were free and to the surface. Getting stuck allowed us to more closely see some of the natural formations of the lower parts of the cave, which were super interesting!

With the significant technical problems of today, we have decided that it would be best to stay home and troubleshoot tomorrow instead of trying to explore the cave with non-functioning equipment. We hope that by Friday, we will be able to have the sonar connected so we can create some maps of the cave (not an easy task), and maybe even connect our second tether so we can explore even deeper!

Mdina, Round 1

Our site for Wednesday was within the walled city of Mdina (http://en.wikipedia.org/wiki/Mdina). The first cistern was located in a restaurant called Bacchus, which was not open for the day yet.

This caused our time for exploration to be slightly shortened, as we had to be out before they opened. After arriving, during setup and some of the time spent in the cistern, about half of the team was able to wander around the restaurant with the owner getting a bit of a history lesson. There was much history to discuss since the room was built between 1657 and 1660! Since it was before business hours, many people transporting supplies for Bacchus were filtering in and out of the front entrance where we were located. Many stopped momentarily to see what we were doing, and were very interested in our sonar maps of the underside of the restaurant as well as the images we were receiving from the VideoRay.

In an effort to rotate drivers during different sites, Christina watched closely as I drove the VideoRay through this site so she could become familiar with the logging process and hopefully gather useful data. After gathering data for awhile, the ToughBook lost communication with the control box. After a quick bit of unsuccessful troubleshooting, it was about time to leave, so we headed to the next location.

The next spot was The Mdina Experience, right down the street. There was very limited space here, and it was during normal business hours.

There was actually a tour group passing right through our site when we arrived. They watched as we brought in and setup all of our equipment, but weren't interested enough to ask any questions. We switched to the Samsung backup since we thought the problem was with the ToughBook and did not have time to continue troubleshooting it on-site. Slightly different connections had to be made when using the Samsung, since it lacked a serial port, but everything worked out and we got the VideoRay through the small entrance and into the water.

Space was limited, so team members not directly involved couldn't really be present, so exploration presented itself again!

Another restaurant was our final location of the day. The cistern here was located in the basement. We had to walk through the restaurant which caused for some further stares of the other patrons. There was an extremely narrow passageway leading down to the site, and our equipment had to make it carefully down the long staircase. To add a bit to difficulty, the passageway was lined with wine bottles so there was little room for error. Luckily, Tyler and I made it all the way down successfully.

After making it downstairs and setting up, the data collection process began. Christina drove for for the first time on this site, and did an awesome job grabbing sonar scans and video for the cistern we were on top of. This cistern was composed of a large circular room and a narrow hallway that didn't lead to anything. We ended our day here, and loved the view off the balcony behind the restaurant!

It’s the Small Things…

Still???

On the flight from Chicago to Frankfurt, we flew on a German airline: Lufthansa. This was a long eight hour expedition, so it was nice to have the two meals included on the flight. Behind me, Joseph was happily eating his chicken-rice-vegetable teriyaki-like dinner with his glass of water. When the steward walked by a second time, he asked me if I wanted another drink. I requested my orange juice, as usual. When the steward asked Joe, he replied, “Water please.” The steward responded, “Still?” Obviously confused why the steward was rudely wondering why he wanted more water, Joe asked, “What?” “You want your water still?” By this time, we understood that the steward was asking if Joe wanted still water, as opposed to sparkling water. We mentioned to the steward the reasoning for our confusion—that we thought he was asking if he wanted water again, since we are never asked to clarify our choice of water in the United States as either sparkling or still. The steward realized the confusion and laughed with us at the different contexts of the word ‘still.’

On the topic of water…

Having been unprepared for a long day away from our apartment in Mdina, we realized we were thirsty and had depleted our repeatedly refilled plastic and metal water containers. I went on a water hunt in the ‘Walled City,’ expecting any institution to gladly fill me up. I asked a woman handing out fliers if she knew where a water fountain was, and she pointed down an alley, but as she did so, she continued to explain (in Maltese) about the flier she just gave me. Deciding that she assumed I was interested in what was on her flier, I thanked her for the information and didn’t go down the alley that I wished had a water fountain. I asked a woman in front of a restaurant for a drinking fountain, but she clearly didn’t understand me, so I pointed to my empty water bottle. She said, “Oh yes, I can throw that away for you.” After clarifying my question, she said water had to be purchased. I went into a little cafeteria and asked for a water refill. An employee directed me to the bathroom, and I filled up. I returned with Andy and a handful of empty water bottles. Following our fill-up in the same bathroom, a lady stopped us: “You can’t just fill up like that and go! You need to leave these bottles here and buy water here.” I explained that I was directed to the bathroom for water previously and didn’t know that we couldn’t fill up water there. “No, I think you knew. You need to leave these here and buy this water. This is a private place; you need to go to a public facility for free water.” We dumped our bottles and left outside the Walled City to a public bathroom, where a gentleman went into the back of the bathroom to fill our bottles in a janitor sink. I later left a tip for him—a few of the bathrooms I ran into worked this way, where a janitor cleaned and monitored the bathroom all day (and some cleaned after each use) and asked for tips. The moral of this long story about water? Water is not expected to be provided complimentary in public places, or even in a private restaurant/café/shop. What did we learn? Fill up extra bottles with Britta filtered water before we leave.

Why the difference in water accessibility? Perhaps water isn’t considered a free resource as it is in the US. Perhaps its availability is less here in Malta. Maybe it’s just not a standard adopted here, and the US has placed bathrooms and water fountains in the same category as handicap accessibility and fire safety. We just made it a necessity, where here in Malta, it’s a privilege. We might consider the lack of water as an inconvenience. A Maltese person might consider our abundance of free water wasteful. Is one way right? No. Just different.

Early Morning Groceries

Last night was the first time in a while that I went to bed at a reasonable hour (9pm). Consequently, I was bright and bushy much earlier than the previous days. Although today it was less bright and more cold and blustery. With an appetite for pancakes, and no butter or syrup in the apartment, I went off on my own about 7am. I found a tiny grocery shop less than two blocks away off the busy and narrow Triq Guze’ Howard street. There was a bustle of about five people gathering their daily groceries of bread, butter, milk, etc. I found my _humble_ container of syrup. It took some time finding it, and only recognized the word “maple,” but decided there wasn’t much else with maple flavoring. Butter, ketchup, soy milk, syrup, and jelly, all humble sizes and pricing about ten euros. I filled my little re-useable fabric grocery bag with my daily groceries in the early morning, anticipating my return the next morning like a native of Malta would. Hopefully within the next week, I will have the map of the area down in my head like a native.

Taste of Maltese Culture

We had our first set of cistern explorations at Gomerino Palace on Tuesday. While waiting to get into the area though, we got a chance to walk down the road and explore a little. In addition to the beautiful landscape and lots of old rock walls and structures, we met an elderly Maltese man who invited us into his garden to show us the statue of St. Paul we had seen from outside earlier.

Beautiful Maltese countryside. There were walls like this all over

Lots of beautiful flowers in bloom and no shortage of interesting buildings.

Shrine/statue of St. Paul in the Maltese persons garden. He saw some of us looking over the low, stone fence and he invited us into his garden to get a better look. Most of the group went to Gomerino to go look at the cisterns as we had just got access to the site, but Brig and I stayed behind briefly to see what the guy had to share.

Side of the shrine. There is a small door (can be seen here somewhat) which leads inside to a small circular room

Inside there were several shelves of religious items set up. It was very interesting to see and brought to mind the statistics we had learned about the large religious presence in Malta.

Talking to the Maltese man. He was very nice but spoke next to no Engligh (only Maltese). It made communication a little hard but with some hand gestures and a charades-like guessing of meanings, we were able to understand the general idea. It was great to meet some of the locals already and it was encouraging to be treated so nicely by someone who was a complete stranger not long before.