Robohub.org
 

Are skintight suits the future of robotic exoskeletons?

by
13 July 2016



share this:
Supersuit in the future? Source: Bigstockphoto

Supersuit in the future? Source: Bigstockphoto

Children with a rare neurological disease were recently given the chance to walk for the first time thanks to a new robotic exoskeleton. These devices – which are essentially robotic suits that give artificial movement to a user’s limbs – are set to become an increasingly common way of helping people who’ve lost the use of their legs to walk. But while today’s exoskeletons are mostly clumsy, heavy devices, new technology could make them much easier and more natural to use by creating a robotic skin.

Exoskeletons have been in development since the 1960s. The first one was a bulky set of legs and claw-like gloves reminiscent of the superhero, Iron Man, designed to use hydraulic power to help industrial workers lift hundreds of kilogrammes of weight. It didn’t work, but since then other designs for both the upper and lower body have successfully been used to increase people’s strength, help teach them to use their limbs again, or even as a way to interact with computers using touch or “haptic” feedback.

These devices usually consist of a chain of links and powered joints that align with the user’s own bones and joints. The links are strapped securely to the user’s limbs and when the powered joints are activated they cause their joints to flex. Control of the exoskeleton can be performed by a computer – for example if it is performing a physiotherapy routine – or by monitoring the electrical activity in the user’s muscles and then amplifying the force they are creating.

Heavy and painful

But despite half a century of research, exoskeletons still aren’t widely used. This is largely because they are usually very uncomfortable to wear for long periods of time, as individuals’ bodies differ from the one-size-fits-all structure of the suits. Some exoskeletons are designed to be adjusted to fit a user’s body better, but if the robotic joints and the user’s real joints don’t rotate in exactly the same position it can produce unnatural motion, causing discomfort or pain. This is made worse by the stiffness of each part of the suit.

Another problem, especially with upper-body exoskeletons, is how heavy they are, usually because of the strong materials needed to support the body weight and the powerful actuators that move the joints. Current suits also aren’t designed to cope with temperature changes or rain, which makes them difficult to use in the real world. And their appearance, which hasn’t been a primary concern of designers so far, can put people off.

Prototype soft exoskeleton glove. Source: Steve Davis.

Prototype soft exoskeleton glove. Source: Steve Davis.

To make exoskeletons more practical and appealing, we need innovations to make them more like a “second skin” than a giant robotic suit. Exoskeletons typically use heavy electric motors, but lightweight actuators such as pneumatic muscles are now being considered. These can produce similar forces to electric motors but at a fraction of the weight. The muscles consist of a rubber bladder surrounded by a woven sleeve. When pressurised, they increase in diameter and contract in length, pulling the joint. They are made from lightweight materials but can generate the force needed to lift many hundreds of kilogrammes.

Soft robotics

However, even these lightweight actuators still need to be attached to a rigid mechanical structure mounted to the user’s body. Myself and my colleagues at the University of Salford’s Centre for Autonomous Systems and Robotics are developing another alternative: soft robotics. This technology uses physically soft advanced materials to carry out similar tasks to traditional rigid robotic devices. They are particularly well suited to interaction with humans as they are typically lightweight which means if they collide with a person they are unlikely to cause injury.

We recently developed a new “soft continuum actuator”, a joint that bends like an elephant’s trunk. Unlike a traditional rigid robot joint, if it encounters resistance in one part of its body it will still bend but at a different location elsewhere along its length.

By equipping a skintight material suit with these actuators, we can create a soft exoskeleton that bends at the precise location of the wearer’s joints. This means the suit will fit a range of users comfortably without needing mechanical adjustment or calibration. Plus, the system is lightweight and can be worn like clothing rather than a bulky mechanical frame.

Exoskeletons are now starting to be sold commercially and we’ll probably see more of them in the coming years. In 2012, paralysed woman Claire Lomas even completed the London Marathon wearing one. But there are still significant engineering challenges to be addressed before we will see widespread use of these systems. For one thing, we need a way for people to power the suits without having to plug themselves in every half an hour.

This article was originally published on The Conversation. Read the original article.



tags: , , ,


Steve Davis graduated from the University of Salford with a degree in Robotic and Electronic Engineering in 1998, and an MSc in Advanced Robotics in 2000.
Steve Davis graduated from the University of Salford with a degree in Robotic and Electronic Engineering in 1998, and an MSc in Advanced Robotics in 2000.





Related posts :



Sense Think Act Pocast: Erik Schluntz

In this episode, Audrow Nash interviews Erik Schluntz, co-founder and CTO of Cobalt Robotics, which makes a security guard robot. Erik speaks about how their robot handles elevators, how they have hum...
19 October 2021, by and

A robot that finds lost items

Researchers at MIT have created RFusion, a robotic arm with a camera and radio frequency (RF) antenna attached to its gripper, that fuses signals from the antenna with visual input from the camera to locate and retrieve an item, even if the item is buried under a pile and completely out of view.
18 October 2021, by

Robohub gets a fresh look

If you visited Robohub this week, you may have spotted a big change: how this blog looks now! On Tuesday (coinciding with Ada Lovelace Day and our ‘50 women in robotics that you need to know about‘ by chance), Robohub got a massive modernisation on its look by our technical director Ioannis K. Erripis and his team.
17 October 2021, by
ep.

339

podcast

High Capacity Ride Sharing, with Alex Wallar

In this episode, our interviewer Lilly speaks to Alex Wallar, co-founder and CTO of The Routing Company. Wallar shares his background in multi-robot path-planning and optimization, and his research on scheduling and routing algorithms for high-capacity ride-sharing. They discuss how The Routing Company helps cities meet the needs of their people, the technical ins and outs of their dispatcher and assignment system, and the importance of public transit to cities and their economics.
12 October 2021, by

50 women in robotics you need to know about 2021

It’s Ada Lovelace Day and once again we’re delighted to introduce you to “50 women in robotics you need to know about”! From the Afghanistan Girls Robotics Team to K.G.Engelhardt who in 1989 ...
12 October 2021, by and

Join the Women in Robotics Photo Challenge

How can women feel as if they belong in robotics if we can't see any pictures of women building or programming robots? The Civil Rights Activist Marian Wright Edelson aptly said, "You can't be what yo...
12 October 2021, by





©2021 - ROBOTS Association


 












©2021 - ROBOTS Association