One of the biggest problems with the development of autonomous cars is the detection of small and vulnerable motorcyclists in traffic.
So the San Francisco chapter of the Iron Order Motorcycle Club recently volunteered the services of seven members to help develop Aurora Driver technology.
They spent a day riding around with cars driven in manual mode by testers from Californian autonomous vehicle company Aurora.
Some of the unique situations tested were detecting riders who were lane splitting, which is only legal in California in the USA, and stopping in an offset position, rather than right in front of a car.
The bikes included four Harley-Davidsons, a KTM, an Indian and a Yamaha cruiser.
Detecting motorcycles is a bit of a headache for autonomous cars development.
In one incident in San Francisco last year a lane filtering rider was hit by a Chevrolet Bolt electric vehicle being driven in autonomous mode.