GOOGLE has written to the California state government requesting permission to test riderless motorcycles on public roads.

The firm’s driverless car project remains in its prototype stage despite autonomously clocking up over one million kilometres. However, documents reveal how Google wants to extend its permission to use driverless cars to other types of vehicles, including motorcycles and trucks.

A prototype motorcycle that balances and steers without a rider has already been built by Google engineers.

Anthony Levandowski, Google engineer and creator of the riderless ‘Ghostrider’ motorbike, had groups protesting outside his home in January over his involvement with the project and his links to Boston Dynamics - a military robotics contractor acquired by Google last year.

Ron Medford, the director of safety for Google’s self-driving car programme, wrote in his letter to the Californian government: ‘It is certainly possible that future testing could include motorcycles or larger commercial vehicles.

‘If some innovator can demonstrate that testing autonomous technology on such vehicles is safe, then they should be allowed to test.’