Sparks

Renewable for robots

 By Robin Wylie

Robotic technology already plays a vital role in modern life, and its influence is set to grow exponentially over the coming decades in order to modernize global production procedures and remote environmental sensing techniques. As the field of robotics continues to grow, green power solutions will be required – and engineers have already come up with various ingenious designs to integrate renewable energy power systems into robots…

Renewable energy is helping to transform mankind’s environmental impact. But by powering the next generation of unmanned robotic vehicles, it is also allowing us to probe the unexplored frontiers of our planet — and beyond. One environment where renewable-driven robots are making progress is the Earth’s polar regions. The budget for scientific exploration in these inaccessible regions is spent mostly on logistics. Mobile robots could help reduce this burden and thereby help expand scientific research in polar regions.

One of these is NASA’s GROVER robot. Short for Goddard Remotely Operated Vehicle for Exploration and Research (and additionally for “Greenland Rover”), GROVER is an autonomous, solar-operated robot designed to roam the Greenland ice pack, carrying scientific instruments with the ability to peer below the frozen surface. GROVER navigates the ice surface on repurposed snowmobile tracks, powered entirely by the two solar panels mounted on top. The panels are positioned in an inverted V shape, which allows them to collect both direct sunlight as well as reflected radiation from the ice surface.

NASA's GROVER on Greenland's Ice Sheet. By Lora Koenig / NASA Goddard

GROVER is equipped with a GPS navigation system, which allows it to move autonomously, along with a ground-penetrating radar, which NASA scientists use to visualize the layers of snow which are gradually accumulating on Greenland’s massive icesheet in an attempt to understand how it gains and looses ice.

Another unmanned vehicle getting a boost from solar energy is another NASA creation, called Helios (pictured below). It’s an ultra-lightweight, remotely piloted aircraft, which is kept airborne by an array of 14 two-blade propellers distributed along its single, curved, carbon-fiber wing. The motors are powered by a combination of solar power, derived from the panels which cover the upper surface of the wing, and a fuel-cell based energy storage system, which keeps the motors running at night.

Launching saildrone in Dutch Harbor. AK ©Saildrone Inc. 2015

Helios is not strictly a robot — the craft is controlled remotely by a pilot on the ground — but it’s a long way from your average drone. With a wingspan of 247 feet, Helios is broader than a Boeing 747, and can carry a payload of over 600 lb.

This eye-catching craft is still in prototype phase, however NASA’s ultimate goal with Helios is to carry a payload of scientific instruments and communications equipment onboard in order to conduct missions lasting up to several months. But robots powered by renewable energy are not confined to Earth. NASA’s Opportunity rover, which is currently active on Mars, is solar powered, as was the Spirit rover, which was active between 2004 and 2010.

These robotic explorers have returned incredible images and scientific data from the red planet. But the next generation of robotic extraterrestrial explorers could harness another renewable resource — wind. One of the most promising prospects for the exploration of alien worlds is a new concept for a wind-driven robot nicknamed “tumbleweed” rovers. Another NASA brainchild, tumbleweed rovers are a conceptual design for a large, wind-propelled vehicle, similar to an inflated ball in appearance, carrying a set of scientific instruments. The vehicles are approximately 6 feet in diameter, and can travel at speeds of up to 13 miles per hour.

Interior of a tumbleweed rover. Credit: NASA

So far the tumbleweeds have yet to make it into space, though they have been successfully trialled in Antarctica, where they were used to collect data relating to temperature, ice thickness and ozone depletion. Yet despite their early stage of development, tumbleweed rovers have been hailed as “a new paradigm for planetary exploration” by NASA scientists. Their low mass and scant power requirements could make these unmanned vehicles ideal for traversing the surfaces of planets or other rocky bodies. Researchers one day envision “swarms” of these tumbleweeds being deployed to places like Mars, Venus and Titan.

SEE MORE: California’s cleantech revolution by Andrew Burger

about the author
Robin Wylie
Freelance earth/space science journalist. Currently finishing off a PhD in volcanology at University College London.