Scientists have developed special algorithms that enable body scaffolds called exoskeletons to adjust to the walk of the person wearing them, making these robotic aids more efficient and personalised.
The enhanced mechanics are able to tweak their behaviour based on feedback from the wearer’s metabolism and other measurements, and the team behind the system is calling it human-in-the-loop optimisation.
At the end of the process, you get an exoskeleton configuration that’s tailored to the wearer’s individual body and walking style, maximising how helpful it is, according to the researchers from Carnegie Mellon University.
“Existing exoskeleton devices, despite their potential, have not improved walking performance as much as we think they should,” says team member, Steven Collins.
“We’ve seen improvements related to computing, hardware, and sensors, but the biggest challenge has remained the human element – we just haven’t been able to guess how they will respond to new devices.”
Right now this human-in-the-loop optimisation requires a treadmill and some sophisticated monitoring equipment, but eventually you could get fitted out for your robotic walking aid in a clinic and then take your programmed profile with you.
The algorithms combine with emulator hardware that tests responses to 32 different patterns, working out which ones help the wearer use their energy more efficiently and which ones don’t.
As the human body adapts to using the exoskeleton, so the exoskeleton can adapt to the individual, making walking more efficient. It’s that loop that makes the technique so useful. For example, one of the settings the system could adjust was the degree of torque, or turning force, applied by the exoskeleton as each joint changed direction.
The exoskeleton was tested on 11 different volunteers, who were put through their paces on the treadmill with scaffolds fitted around their ankle and lower leg.
By the end of their experiments, the researchers had created customised walking profiles that saved users up to 24 percent of their energy compared to using standard exoskeleton configurations.
Whether it’s people with disabilities who have trouble walking as normal, or emergency aid workers who need to call on some robot-assisted superpowers to shift rubble or cover ground, that extra energy-to-power ratio has plenty of potential uses.
Energy efficiency is only one way to measure the effect of an exoskeleton though, and the researchers say future studies could look at limb speed, balance, heart rate, and even perceived comfort as well.
Plus, the same techniques could be applied to artificial prosthetics too, and the team behind this research says there are all kinds of possibilities.
“I could see them in the far future being used to make sports more exciting,” one of the researchers, Kirby Witte, told Kaleigh Rogers at Motherboard. “You could have people with exoskeletons slam-dunking on hoops twice as tall as they are now, doing crazy, sci-fi stuff.”