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Sunday, December 2, 2007: Weeks of testing finally pay off
Today was one of the most eventful SCINI days we have had in a long time. BLee, Bryan, Bob and myself planned on launching SCINI so that we could evaluate her performance over several engineering test that BLee had established. These tests were going to help determine if SCINI was ready to take on science missions. In the past I felt we have really rushed into getting SCINI in the water for science missions without having strict test to judge her performance. But today’s test was solely focused on maneuvering and reliability. The past two weeks have focused on making the robot reliable and has helped to build our confidence. Now after weeks of testing SCINI was ready to get wet once again.


The weather today started off with blue skies and lots of sun. It was as if Antarctica granted SCINI approval to dive beneath the ice shelf. In the lab Bob did a dry run of setting up the whole computer system with some help from Bryan. Bob is the cohesion in this project and he will be the one to carry on the lessons from this season to the next two years. During this dry run BLee and Rusty prepared our navigation holes while I worked the GPS system. These simply tasks sound quick and easy but let’s not forget we are in Antarctica. By the time everyone was on the same page, task wise, and it was time for lunch.

After a fabulous Sunday brunch we were packed, loaded and ready for our test. At the dive site we unloaded everything and once again allowed Bob to set up the operation but this time without the help of Bryan. This was Bob’s true test and he passed it with only asking one question. Before SCINI is dropped in the water we have established a pre-deployment checklist to ensure that all of the motors spin and in the correct direction, the lights turn on and off and that we are able to capture video. Thanks to previous weeks of testing SCINI passed the test without any problems and was ready to get wet. BLee took over the piloting position while Bob deployed the robot.

Once in the water the first test we conducted was a maneuverability test. One example of this test was to drive the robot laterally so that the vehicle would move sideway without changing its direction. SCINI passed all six maneuverability test and we moved onto the depth test. We have two sensors that measure vehicle depth. One sensor is located on SCINI and the other sensor is located on the transponder of the navigation system. The navigation system has a default depth sensor that we wanted to verify with an external sensor. To check the depth of both of the sensors we can place a tape measure down the dive hole and compare the readings of the senor to the tape. Both of the depth sensors checked out within a meter of each other and this was acceptable. Next we moved onto the navigation test. First we tested the noise levels of all three transducers while the robot was at a standstill. If there is too much noise our navigation system won’t work and we will have sporadic navigation that will be unusable. Our navigation noise levels checked out just fine and we moved onto navigation tracking while moving. There was some difficulty driving the vehicle at this point and it could have been a result of several things. For whatever the reason we were unable to complete our maneuverability navigation test so we moved onto driving test. These tests were similar to the previous ones but required us to pick an object at some distance away and follow it straight ahead and another object vertically in the water column. The two other tests required SCINI to hold a position in the water column while looking at an object and was followed by a test that point the camera bottle at the bottom of the ice. These tests were designed to judge if SCINI is capable of mapping physical features along the ocean bottom. Again due to driving difficulties we were unable to complete the entire driving test.

We were unable to complete many of our designed tests but left the dive site with a huge accomplishment. The total time of our test ran nearly five hours and this was the longest duration we had ever run SCINI without turning her off. Not only does this prove the reliability in a single dive but five hours is much longer than any science dive will ever require. So in the end we had some victories and we will head back to the lab to plan out where SCINI should go from here.

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This material is based on work supported by the National Science Foundation under Grant No. ANT-0619622 ( Any opinions, findings and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.