May 17 2010
New Zealand researchers have designed a new kind of sensor that allows sports scientists to measure the impact forces of athletes’ performance.
Sports players wearing these sensor devices will allow sports scientists to assess their performance and reduce the likelihood of potential injuries.
Kean Aw and team from the University of Auckland have written in the ‘International Journal of Biomechatronics and Biomedical Robotic’ about new type of materials called ionic polymer metallic composites (IPMCs). These IPMCs generate electricity when they are compressed. The IPMCs are also light weight, long-lasting and flexible to the extent that they can be easily designed into sensor equipment. Impact sensor devices can be worn by athletes without hampering their performance.
Ionic polymers such as Flemion and Nafion are generally used to produce ionic polymer metallic composite materials. The Flemion and Nafion polymers are coated with conducting metals such as gold and platinum.
The IPMC sensor devices can be placed inside the runner’s shoes. This sensor will help in determining the impact energy of the foot as it hits the hard surface of the ground. The sensor can also be inserted into the shoulder pads of rugby players to assess the impact forces used during play.
Earlier, scientists have used ionic polymer metallic composites as artificial muscles. When an electric current is applied to the artificial muscles, ion movements produce an electrostatic repulsion that makes the muscles flexible. In the sensor technology, the same effect is applied in the reverse order in which the material gets stretched when the migration of ions produce an electrical current.
The IPMC sensor device has been tested in the lab. Researchers used different impact forces and matched those data with those obtained from standard measurement techniques. The tests showed that the IPMC sensor device needs to be calibrated with both low and high impact forces before testing it on the players. Nevertheless, high and low voltage measurements from the IPMC sensor can be easily changed into an impact force measurement with an accuracy of 10%.