All posts by Katie Woodward

Forget Cybermen and Iron Man: the next generation of soft, flexible robots is here

Traditionally, robots have been machine-like, rigid, fast and efficient contraptions, much like Doctor Who’s Cybermen and Tony Stark’s Iron Man suit.

But, researchers at École polytechnique fédérale de Lausanne’s (EPFL) Reconfigurable Robotics Lab (RRL) have turned this notion on its head with their soft robots.

These flexible, reconfigurable and air-actuated robots behave like human muscles and could be used in physical rehabilitation.

The soft robots are powered by muscle-like actuators, and are designed to be used on the human body to help people move, particularly for those undergoing physical rehab.

The muscle-like actuators

The muscle-like actuators

Made of elastomers, including silicon and rubber, they are controlled by changing the air pressure in specially designed ‘soft balloons’, which also act as the robot’s body.

In addition to patient rehabilitation, these soft robots can be used to handle fragile objects, in biomimetic systems, as well as for home care.

“Our robot designs focus largely on safety,” explained Jamie Paik, RRL director. “There’s very little risk of getting hurt if you’re wearing an exoskeleton made up of soft materials, for example.”

Controlling actuators

In an article published in Nature – Scientific Reports, the researchers showed that their model can accurately predict how a series of modules moves. The cucumber-shaped actuators, as seen in the video, can stretch up to five or six times their normal length and bend in two directions.

“We conducted numerous simulations and developed a model for predicting how the actuators deform as a function of their shape, thickness and the materials they’re made of,” said Gunjan Agarwal, lead author.

A test was conducted to show that different materials could be used in the construction of the soft robot. One of the variants, for example, consisted of covering the actuator in a thick paper shell.

“Elastomer structures are highly resilient but difficult to control,” Agarwal explained. “We need to be able to predict how, and in which direction, they deform. And because these soft robots are easy to produce but difficult to model, our step-by-step design tools are now available online for roboticists and students.”

Rehab belt

Other researches from RRL have been working to develop these soft robots for medical purposes.

One of their designs is a belt made from several inflatable components, which holds patients upright during rehabilitation exercises and guides their movements.

“We are working with physical therapists from the University Hospital of Lausanne (CHUV) who are treating stroke victims,” said Matthew Robertson, the researcher leading the project. “The belt is designed to support the patient’s torso and restore some of the person’s motor sensitivity.”

All images courtesy: ©Marc Delachaux/EPFL 2016

All images courtesy: Marc Delachaux / EPFL 2016

But the potential applications for the soft actuators used in these robots are endless. The EPFL team, for example, is using the technology to develop adaptable robots capable of navigating in cramped or hostile environments.

Because they are soft and flexible, the robots should be able to withstand squeezing and crushing.

“Using soft actuators, we can come up with robots of various shapes that can move around in diverse environments,” Paik noted. “They are made of inexpensive materials, and so they could easily be produced on a large scale. This will open new doors in the field of robotics.”

The space brain problem: will astronauts remember their journey to Mars?

A new study by scientists at the University of California, Irvine has raised concerns about a phenomenon called “space brain” – the fact that astronauts travelling to Mars could risk chronic dementia after being exposed to galactic cosmic rays.

Professor of radiation oncology Charles Limoli and his colleagues have found that exposure to highly energetic charged particles, much like those found in galactic cosmic rays, causes significant long-term brain damage in rodents. The exposure resulted in cognitive impairments, as well as dementia.

The study has been published today in Nature’s Scientific Reports, and follows another study last year that showed shorter-term brain effects from exposure to galactic cosmic rays.

“This is not positive news for astronauts deployed on a two-to-three-year round trip to Mars,” Limoli said.

“The space environment poses unique hazards to astronauts. Exposure to these particles can lead to a range of potential central nervous system complications that can occur during and persist long after actual space travel – such as various performance decrements, memory deficits, anxiety, depression and impaired decision-making.

“Many of these adverse consequences to cognition may continue and progress throughout life.”

Image courtesy of NASA. Above: Image courtesy of NASA/Paul DiMare

The study, which was carried out at the NASA Space Radiation Laboratory in New York, subjected rodents to charged particle irradiation. The rats were then sent to Limoli’s laboratory for analysis.

After six months of exposure, the scientists found significant levels of brain inflammation and damage to neurons. The brain’s neural network was impaired through the reduction of dendrites –short branched extensions of nerve cells, along which impulses received from other cells at synapses are transmitted to the cell body – and spines on those neurons, disrupting the transmission of signals among brain cells.

The radiation also affected “fear extinction” – a process in which the brain supresses prior unpleasant or stressful associations.

“Deficits in fear extinction could make you prone to anxiety, which could become problematic over the course of a three-year trip to and from Mars,” Limoli warned.

Images courtesy ofNASA. Featured image courtesy of NASA/Paul DiMare

Images courtesy of NASA. Featured image courtesy of NASA/Paul DiMare

Similar types of more severe cognitive dysfunction, which often results in poor performance on behavioural tasks designed to test learning and memory, are common in brain cancer patients who have received high-dose radiation treatments.

Although dementia-like deficits in astronauts would take months to appear, the time required for a mission to Mars is sufficient for these impairments to develop.

The study is part of NASA’s Human Research Program, which undertakes work to predict, assess and solve the problems that humans encounter in space. Investigating how space radiation affects astronauts is critical to future space exploration, and NASA must consider the risks as it plans for missions to Mars.

Partial solutions to the problem are being explored, such as designing spacecraft to include areas of increased shielding.

“But, realistically, the highly energetic charged particles will traverse the spacecraft regardless, “and there is really no escaping them,” Limoli warned.

Preventive treatments, however, could be more effective. The UCI team is currently working on pharmacological strategies involving compounds that scavenge free radicals and protect neurotransmission.