Award-winning New Zealand scientist's creation of life-like reflexes in artificial muscles opens up new realms of science

Part 5 of a 6-part series

When Dr Benjamin O'Brien invented technology that gave artificial muscle devices lifelike reflexes, he unlocked a world of endless possibilities.

Picture prostheses that can think, or soft robots that can adapt to changing environments.

The young University of Auckland scientist's breakthrough - the invention of what's called the dielectric elastomer switch - holds worldwide ramifications.

As well as blue-sky research, Dr O'Brien is deeply involved in high-tech commercialisation.


With colleagues Dr Todd Gisby and Associate Professor Iain Anderson, he co-founded StretchSense Ltd, a company that sells sensors for fine-tuning athletes, helping people to recover from injuries, or control virtual avatars for motion capture and gaming.

In its first year, StretchSense has grown to 11 people, won two categories at the New Zealand Innovators Awards and shifted into a factory to support its increasing international sales volumes.

Last year, this mix of fundamental research and commercial activity earned him the Prime Minister's MacDiarmid Emerging Scientist Prize.

At the core of the science are Electro-Active Polymers, known as EAPs, rubber bands that respond in a useful way to electricity.

Since the technology was invented in California 15 years ago there has been a worldwide effort to develop it further.

But Dr O'Brien and his colleagues realised when they joined the field back in 2006 that materials were simply not enough.

"You also need clever electronics if you want to do anything useful," he told the Herald.

"We became very good at this - developing electronics for other research groups and eventually we started selling demonstration devices using artificial muscles in clever ways."

StretchSense CEO Ben O'Brien talks about the Stretch Sensor technology and how it can be used. Video / StretchSense

His own journey began when a friend noticed an advertisement for a summer studentship in Associate Professor Anderson's Biomimetics Lab.

From there, he completed his final-year project in mechatronics, working with the lab in building self-sensing artificial muscles.

His PhD investigated controlling groups of artificial muscles and was followed by a post-doctoral research project that resulted in the completion of an artificial muscle computer.

The people he met along the way would become great friends and form the backbone of his new venture.

During his PhD, he invented the dielectric elastomer switch, which allowed artificial muscles their own simple reflexes, just as real ones have.

"Artificial muscles with reflexes are very exciting for anyone building soft robots and lifelike prostheses," he said.

"The problem we were trying to solve was, how do you get a large number of artificial muscles to work together as a team?"

The solution was to build reflexes into these devices, so that each one would react automatically and the collective output would prove both clever and useful.

Building a sophisticated device took around nine months, and after testing different materials, it took four months to find the one that exhibited the correct behaviour.

The prototype "worked horribly" but allowed him to refine his materials, design and fabrication techniques until he had a nicely working device.

Its group of artificial muscles was smart enough to play with a ping-pong ball, rolling it around a set of rings without any higher level control.

Dr O'Brien was further able to show artificial muscles could be used to make logic circuits, opening up the intriguing possibility of combining a large number of logic circuits into an artificial muscle computer.

He built a computer, but it was extremely slow and probably would have required billions of years to do a simple calculation, he said.

"However, despite these limitations it was Turing-complete, which means it could solve any problem given enough time and memory."

In layman's terms, you could use it to play the Battlefield 4 video game, but the time lag would be terrible.

In 2012, Dr O'Brien, Dr Gisby and Associate Professor Anderson launched StretchSense out of the Biomimetics Lab, set up with a mission of making it easy to measure human body motion. "Our sensor product is basically a rubber band with Bluetooth - when you stretch the sensor it talks to your smartphone and tells you how much it has been stretched," Dr O'Brien said.

"This is fantastically exciting if you want to measure body motion for health and rehabilitation, animation and gaming, or sports training."

One of his concepts harnesses his interest in Brazilian ju-jitsu, a martial art based around leverage and submission holds.

"I have this idea of building a sensing suit and smartphone app so that the student can see in detail both the nuances of a position, but also see an animation of their submissions.

"For example, when performing an armbar, what is the perfect angle for the hips to put pressure on the elbow?"

There's also potential to tap into wearable computers, a field he suspects is going to boom in coming years.

"At the moment if you are angry with your computer you can stomp on it, but if that computer is built into your contact lenses you might think twice," Dr O'Brien said.

"The point is that once computers are intimately coupled to our bodies they need to become more emotionally aware - they cannot antagonise us or there will be genuine consequences."

One idea was to explore the use of soft sensing technology to measure body language - gestures, posture and agitation - to create wearable computers that are more aware.

As the field of EAPs expanded, the scientists would remain focused upon the development of new materials and control electronics.

The final frontier, which StretchSense is at the heart of, is commercialisation.

"The challenge has been getting the technology into a useful form that can be built upon and directly used for customer applications, and we have achieved this with sensors," Dr O'Brien said.

"I see this as a very important process because commercial success requires technology that is not only functional, but also easy to use."

In its first year, StretchSense has grown to 11 people, won 2 categories at the NZ Innovators Awards & moved into a factory to support its increasing international sales volumes. Photo / Dean Purcell
In its first year, StretchSense has grown to 11 people, won 2 categories at the NZ Innovators Awards & moved into a factory to support its increasing international sales volumes. Photo / Dean Purcell

Wearable computers may become daily attire

Could emotionally-aware computing technology become so much a part of our lives that we'd wear it every day?

Dr Benjamin O'Brien believes so, yet there are still a lot of unknowns.

"First, wearable computing needs to become commonplace - I think this will happen but when is hard to predict," he said.

"You will hear about it for a long time and then all of a sudden you will blink and it will be everywhere."

Wearable sensing also needed to measure emotions in a useful way, he said.

"We don't really know if this is possible - that's why we are going to do some science first by building a body suit and testing it."

Finally, people needed to tolerate wearable sensors in their everyday lives.

"I think this is a no-brainer as already you are seeing a proliferation of wearable sensor devices out there with many benefits, showing that people not only tolerate but they enjoy being able to sense their bodies."

Microsoft researchers recently designed a smart bra which monitors a woman's heart rate, breathing, skin activity and movement in an attempt to prevent emotional overeating.

Similar examples have included a "power shirt" able to generate electricity to power small electronic devices, Ray-Ban style sunglasses that serve as a laptop and smartphone, and a wearable onesie for babies that includes sensing technology detecting changes in temperature, motion and respiration.

Tomorrow's feature will look at Kiwi researchers' experiments with Google Glass, the first truly wearable computer that could be sold in large numbers for general purpose use.

The full series

Part 1: Tackling the obesity epidemic
Part 2: Solving the human jigsaw puzzle
Part 3: The Kiwi-made biotech wonder
Part 4: Learning mental time travel
Part 5 (today): The birth of the artificial muscle
Part 6: The age of wearable computing