Editor's Note: This post marks the second in a short series we're featuring on the Unreasonable at Sea program. Check out the first installment "Entrepreneurs Take on the World -- By Cruise Ship

Call it an aquatic update.

It's been six weeks since the mobile-accelerator program Unreasonable at Sea set sail on the MV Explorer for a four-month trip around the world, and as we promised, we're checking in with our intrepid entrepreneurs. First up is Cesar Harada of Protei, who dropped us a line as he was departing Singapore.

Through Protei, Harada hopes to make an open-source sailing robot, or drone, that cleans up environmental waste. But he still has major challenges, which he hopes to tackle throughout the voyage. Not only is he aiming to crack the engineering puzzle that is building a shape-shifting hull, he wants to create a global community that develops the technology. He'll also need to fine tune his technology, which has multiple applications -- from cleaning up oil spills to plastic pollution and more.

"It is hard to think of a better place as the middle of the ocean with some of the world's most notable entrepreneurs to reinvent how technology can connect us back with the environment in a meaningful and sustainable way," he says.

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Thus far, the CEO and his colleagues have visited Hawaii, Japan, China, Hong Kong, Singapore and they're currently are in Burma. Given Harada's Japanese heritage -- and the March 2011 earthquake and tsunami that spurred a level seven nuclear crisis, the worst since Chernobyl -- he was most eager to revisit his roots and start to apply his technology, which can also be used to clean up radioactivity.

"Half of my family lives in Niigata, and I was horrified [when the tsunami hit]. Hundreds of thousands of people were evacuated," he recalls.

When the Unreasonable ship docked in Japan, Harada and his team built underwater radioactivity sensors in Tokyo. They then drove to Fukushima and immersed the instrument at the border of the exclusion zone to measure significant amounts of radioactivity on the seabed.

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They also were able to meet with FuRo (Future Robotics Laboratory of Chiba University) that provides TEPCO, Japan's national energy company, with "Quince," the remotely-operated robot that was sent inside the damaged reactor for remote sensing and operations. "We are now integrating FuRo Electronics in Protei design and hope to come back as soon as we possibly can to deploy a fleet of Protei in Fukushima surrounding waters," Harada says.

The community environment that the academic host company Semester at Sea fosters has been beneficial to Protei's development, notes Harada. The term "We're in the same boat" has taken on a whole new meaning, he adds. "We share meals. We work together. We celebrate our small victories together. We cheer each other up in hard moments."

He's also learning more about himself. "I like people, but it's actually hard for me to really like people -- until this trip," says Harada. I usually focus on work. Yet, I've connected quite intensely with the mentors and the organizers." The program also boasts 50 faculty members and 600 Semester at Sea students, with whom the traveling treps interact.

Related: Crisscrossing the Globe In the Name of Entrepreneurship

While prior to the voyage, Harada was focusing on Japan, it's China that may have proven most impactful to Protei's future so far. "We found amazing manufacturing partners in Shenzhen. We have seen that our technology is relevant for environmental measurement there, and we have found a place where we can scale Protei production."

Following the voyage's completion in May, Harada now plans to relocate Protei from his native Paris to Shenzhen, one of the world's centers for electronic manufacturing.

-For more from Harada on his journey and Protei's development check out his blog,cesarharada.com.