Getting a grip

Australian cricket bat promises more comfort thanks to a handle equipped with piezoelectric sensors and a vibration-absorbing synthetic material. Siobhan Wagner reports.

Australian cricketers don’t seem to need much help scoring runs, but a hi-tech cricket bat from sports manufacturer Kookaburra could do just that.

Its innovative design reduces zinging vibrations felt by batsmen when they strike the ball and gives them greater freedom to hit out. The handle is equipped with piezoelectric sensors, actuators and a vibration-absorbing synthetic material that converts shockwaves from ball impact into heat and dampens vibration by generating waves in the opposite direction.

The bat’s carbon fibre shell with a polymer insert employs technology called active vibration control which can effectively increase the ‘sweet spot’ — the zone in which batsmen experience the least discomfort.

The man behind the design is Sabu John, an Indian-born, UK-educated mechanical engineer from Melbourne’s RMIT University. The idea for the bat first came to him in the 1990s. He said he noticed vibration reduction developments in sports equipment like baseball bats and tennis rackets in the US market.

‘I thought it would be nice to try the same technology on cricket bats,’ he said. ‘I looked at the laws of the game and found that while there were restrictions about the blade, the handle specifications were largely absent.’

John teamed up with Kookaburra through a connection he had with the research director of the company. After receiving government funding in 2002, he began work on the project with two doctorial students. The group went through at least three earlier designs before arriving at their final product.

The bat’s vibration control technology is similar to that used in baseball bats, tennis racquets and other sports equipment, but John noted that the exact technology could not just be re-applied to cricket bats because the dynamics and materials used are very different. For the handle of the bat, John said the researchers re-used existing electric shunt circuit technology and adapted it to the specific characteristics of the bat. ‘One major problem was the non-linear behaviour of wood,’ he said. ‘We used alternative materials technology to overcome this difficulty.’

The team used polymeric carbon-fibre components, which had to be specially designed to engineer antinodes of vibration in ‘suitable’ locations on the handle.

Antinodes are the maximum amplitude of vibration waves caused when the ball strikes a bat. Its vibration-absorbing material will dampen this impact and generate waves in the opposite direction.

John is hesitant to reveal too much because he is still awaiting a patent.

While a new hi-tech bat might raise the eyebrows of cricket purists, John insists the bat is within International Cricket Council (ICC) regulations, and will in no way de-skill the game. ‘The bat is not expected to deliver sixes every time it strikes the ball,’ he said. ‘All the skills of a top batsman will still be needed — which is to try and hit the ball with the middle of the bat. nothing has changed.’

Still, while the bat might be within the rules, John said he wouldn’t be surprised if it raised eyebrows among regulators. ‘About a 100 years ago, rubber — then a hi-tech material — was incorporated into the handle of a bat to do exactly what we are trying to do,’ he said. ‘All we are attempting today is to do the same thing with new-age materials and systems to further sort out an old problem. The game’s lawmakers should look at this development in the same light.’