May 24, 2011      

Power storage is the Achilles’ heel of the personal electronics world, the green-car world, and maybe the robotics world too. Home and office service robots can head back to a recharging station when their batteries run low. But charging takes time, and a power hook-up isn’t always available. What’s more, transporting extra batteries may not be the best option in all situations. U.S. soldiers must carry 80 pounds of batteries just to keep a unit’s radios running, according to the journal Environmental Health Perspectives. Robots, particularly those used by the military, would consume even more energy.

Enter hydrogen fuel cells as a possible alternative. Based in Folsom, Calif., Jadoo Power Systems Inc. is one company that’s already applying what is essentially off-the-shelf fuel-cell componentry to military robotic applications. Last year, the company, working with the U.S. Navy’s Office of Naval Research, successfully tested a specially designed lightweight fuel-cell stack as the power source for the avionics and payload on a NAVAIR Mako unmanned aerial vehicle (UAV).

One member of the research team, Timothy Eden, head of the Material Processing Division at Pennsylvania State University, notes, “The fuel cell with external fuel canisters has the potential to double the payload run time compared to a conventional battery system.”  

Jadoo sees additional robotics applications for its fuel-cell technology in search-and-rescue operations and to power undervehicle inspection robots at security checkpoints, both instances where fast recharging is essential to keeping equipment in continual operation. Moreover, company officials note that a solar-powered system able to create hydrogen from site-available water via electrolysis could form part of the robot’s overall system design, making it unnecessary to transport hydrogen to a battle or disaster zone.

Jadoo is also working with the U.S. Air Force to develop ammonia-borane-based materials for use in an advanced hydrogen-generation system for UAVs. Ammonia-borane is a white-colored solid rich in hydrogen that can be fabricated into pellets no larger than an average person’s small finger. The result, the company claims in a statement, “is a dramatic improvement in system size and weight,” critical to UAVs, of course. The hydrogen-borane also improves energy density while reducing the overall system’s cost.

Others see more placid applications for fuel-cell-powered robots. Check out the presentation by iRobot research engineer Pavlo Rudakevych (www1.eere.energy.gov/hydrogenandfuelcells/pdfs/128.pdf) at the U.S. Department of Energy’s Energy Efficiency and Renewable Energy website, which looks at oil drilling and industrial applications for fuel-cell-powered robots.

Elsewhere, Swiss designer Fabian Zimmerli (http://www.fazi.ch/uk/portfolioweedmaster2.html) envisions a methane fuel-cell-powered agricultural robot, no larger than an ice chest, with sufficient intelligence to distinguish a farmer’s plants from unwanted weeds, thus avoiding the need for herbicides. The methane could be captured from decaying organic materials. Swarms of fuel-cell-powered robots could revolutionize farming someday-and that’s just one example of the benefits the technology might bring to robotics.