ASU Researchers Develop Jetpack Technology to Help Ground Troop Mobility
To run faster, training, proper diet and weight lifting are your best bets. While we don’t often find ourselves in positions where we need to run faster, there are people in professions where being able to run four or five seconds faster can mean the difference between life and death. Now, researchers are trying to make that speed boost a reality.
“Can we enhance that mobility of our soldiers so that they can maneuver, get out of bad situations, or even run fast enough to catch somebody that’s running away?” said Dr. Joseph Hitt, a former program manager at the Defense Advanced Research Projects Agency, or DARPA.
Hitt says until now, adopting technology for ground troops has been a slow process.
“Our dismounted soldiers have capabilities similar to what they had in Vietnam," he said. "Over those same years we have brand new aircraft carriers, we’ve had shuttles that went to the international space station.”
The average U.S. ground soldier carries as much as 100 pounds of gear, three and a half times more weight than enemy soldiers. Historically, most battles involving U.S. troops have been fought on foreign soil, where opposing forces have better knowledge of local terrain and access to resources. American troops are forced to carry everything they could possibly need for battle.
“What that causes is a perception among our potential adversaries that a place where they think they can find us vulnerable is at the dismounted scale," Hitt said. "So, they want to fight us on the ground on foot because that’s where they think they have some equal match.”
Even though ground battle can be brutal, injury from attack is not usually the main reason troops are pulled out of their deployments. Strain from the gear weight is the chief culprit. To keep the upper hand, U.S. military researchers are trying to lighten the stress on soldier’s bodies. The answer, these researchers say, might be in wearable robotics.
“Kind of a holy grail in robotics has been this idea of can you develop a device that actually overcomes its weight burden and gives you metabolic augmentation, so it’s actually easier to walk with the device or run with the device than no device at all," said Dr. Thomas Sugar, a professor of Engineering and Robotics at ASU.
In Sugar's lab, projects, parts, prototypes and tools are scattered about with whiteboards covered in math equations. Student Jason Kerestes excuses the mess, but this place looks like an inventor’s dream. He introduces me to his 4 Minute Mile project, a jetpack made for running.
“We’ve kinda gone through this development process of how can we make the robots as comfortable as possible while reducing their weight as much as we can,” said Kerestes.
It fits just like a backpack. The team experimented with several frames, starting with stiff aluminum to using a plastic mold. Kerestes hopes to move to a stronger and lighter weight carbon fiber frame soon. But the prototype testing has had it’s errors.
“We actually had a soldier run in that and a thrust bearing bolt vibrated loose because the fans are actually spinning at 60 to 70,000 RPMs," Kerestes said. "So there’s some really unique vibrations that occur within the frame itself.”
Two fans propel the pack. Each consumes roughly 2500 watts of power at full thrust. To compare, a CFL bulb consumes only about 15 watts, so the researchers turned to high-grade lithium ion batteries. Thick wires run to the propellers that sit next to each other in what looks like two shortened coffee cans on the lower back, positioned nearly 45 degrees downward. While it took multiple trials to get to this stage, Dr. Sugar says the 4MM project is getting closer to it’s goal.
“When you wear that jet pack, even though it’s an extra 11 pounds, it’s actually easier to run," Sugar said. "So we’ve had people run faster with a lower heart rate.”
So I was curious. How would I do with it? With permission I put the jetpack on, strapped in and fired it up.
“My shoelace came undone!” I said.
“It’s a really interesting feeling you know," said Kerestes. "We had one military soldier describe it as it feels as if the hand of God is pulling you along.”
“And, I’m out of breath. That’s amazing,” I replied.
“Yeah, it’s a, you know honestly, it’s an exciting technology that can be used for soldiers, but it’s also a lot of fun,” Kerestes said.
The project needs more testing before use in the military and is years away from public use if it gets to that point. But Kerestes points out that idea isn’t far fetched.
“You know, GPS was a concept originally funded by DARPA as well," said Kerestes. "And now it’s something that just about every person has. So if we can continue that process of human/machine integration and develop cutting-edge machinery and robots to integrate with humans and assist people, there’s no limit to the potential.”
Until then, if you want to run faster, diet and exercise is still your best bet.