Artificial muscles: Bridgestone working on walking machine

Bridgestone Corporation doesn’t just make tyres. In fact, the company says it is committed to helping people realise an “active and healthy lifestyle” through the utilisation of technologies and expertise in a whole range of rubber-related fields. This commitment can be seen in a joint development venture it is undertaking to improve the health of senior citizens.

The joint project announced today is with Professor Kenji Kawashima from Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University (TMDU) and focuses on the development of a walking training machine for people with weakened or atrophied muscles. The training machine utilises pneumatic rubber artificial muscles; these are attached to the user to assist when walking or applying loads. The aim of the device is to help the user increase physical strength. A prototype has already been completed, and verification tests will commence in 2018.

The work focuses on developing a walking training exoskeleton that uses the rubber pneumatic artificial muscles created by Bridgestone and the system control technologies developed by Professor Kawashima. In addition to helping to build up strength, the artificial muscles provide assistance when walking.

Bridgestone developed the artificial muscles by drawing upon experience gained through the development of tyres and rubber hoses. The rubber pneumatic artificial muscles it came up with are a type of McKibben artificial muscle, made up of a rubber tube and a cylindrical reinforcement layer made of fibres wrapped around the tube. Changes in air pressure within the tube cause the tube to contract or expand, mimicking the movement of human muscles. As the artificial muscles are lighter and more flexible than other actuators such as motors, a training machine that uses them places less physical burden on the user.