Robots who can handle soft tissue

28 November 2017
Associate Porfessor Bioengineering Leo Cheng
Dr Leo Cheng

How does a rigid, steel robot grip a piece of fruit and know it is gripping it hard enough so it won’t drop, but not too hard so it doesn’t damage it?

The answer to this is complicated. While traditional robots can carry out multiple tasks, they are made of steel and designed for precise interactions. Now the challenge is to develop robots that can interact in a soft, flexible way with things like fruit and vegetables, meat, plants and humans.

“Soft materials or tissues are often subject to damage or injuries when handled by rigid robots and so far there have been few attempts to improve this situation,” says associate professor of Bioengineering, Leo Cheng.

Dr Cheng is a spokesperson for a unique collaboration between the University of Auckland’s Bioengineering Institute and Faculty of Engineering, and the University of Stuttgart in Germany, to advance research in soft tissue robotics internationally.

The collaboration is part of the New Zealand-Germany Science and Technology Cooperation Agreement, which has just celebrated 40 years with a visit to New Zealand by the President of Germany, Frank-Walter Steinmeier.  

Specifically the robotics collaboration, called an International Research Training Group (IRTG), allows for 20 professors, 10 from each institution, to supervise 20 PhD students with a unified aim of researching different aspects of soft tissue robotics.

“Each student will interact closely with one supervisor in Auckland and one in Germany,” says Dr Cheng. “We will integrate all these students with extended research exchanges between the two universities.”

Over four years the students will work on projects to create computer simulations of soft tissues, measure electrical activity of muscles and find ways that the robots can get information in real time by using sensors and sensor technology. “This will enable information to be fed back to the robot so it can grip and un-grip appropriately,” says Leo.

One student is already using Electromyography (EMG) – an electro-diagnostic medicine technique for evaluating and recording the electrical activity produced by skeletal muscles – to measure electrical activity in human arms.

“So if an arm muscle flexes we can record the electrical activity causing that muscle to contract. We can use these measurements to potentially interact with a robot,” explains Dr Cheng.

Another student, currently visiting Auckland from Stuttgart, is constructing a mathematical model of the upper arm and modelling how the muscles in the arm work.

“So upper arm motion is being simulated on the computer,” says Dr Cheng.

He hopes the long term result of the New Zealand German collaboration will be to set the standard for soft tissue robotics globally.

“And eventually the knowledge gained can start to be applied to industry.”



Tess Redgrave| Media Relations Adviser

Auckland Bioengineering Institute


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