Law-makers have been urged to consider the time it takes a driver to take back control from automated systems after new research revealed a significant gap in reaction times.
The latest Venturer report by AXA and Burges Salmon found delays of up to three seconds between a vehicle deactivating its autonomous mode and a driver taking back control.
At 70mph that equates to a car travelling 308 feet with neither the human driver or autonomous system in control.
The report calls for for legislators to take this handover delay into consideration when formulating regulations around self-driving vehicles, as well as the effects of a driverâ€™s abilities.
The Venturer research project is a collaboration between academic, public and private bodies examining the possibilities and obstructions to the introduction of autonomous vehicles. Its latest report focuses on safety, technical and legal implications of the the transfer between human and computer control while a car is in motion.
It raises questions over who is liable for the handover period between self-driving systems and suggests that staged handover systems may be needed to ensure a safe transfer of control, especially at higher speeds.
As well as the gap in control, the research shows that following handover, participantsâ€™ driving styles were slower and had a marked delay in achieving normal performance when retaking control at speeds ranging from 20-50mph.
It notes: â€œThe findings…suggest that designers of AV technology with handover functionality need to proceed with caution. The experiments highlight the need to consider human performance under multiple driving conditions and scenarios in order to plot accurate takeover and handover time safety curves.”
The report also highlights the risk of â€œde-skillingâ€ among drivers who become overly-reliant on autonomous technology and suggests drivers might need specific training for operating autonomous cars.
Practical and safety questions
David Williams, technical director at AXA UK, commented: â€œThe exciting part about Connected Autonomous Vehicles (CAVs) is that they open up a world of opportunity and mobility for those who may have previously struggled. At the same time, it also raises questions regarding practicalities, liability and, most importantly, safety. The latest Venturer report investigates just one aspect of the driverless experience â€“ the handover stage â€“ and calls for greater understanding of how motorists will adapt to this new process.â€
One of the main conclusions in the report is that while legislators need to take into consideration the handover period while determining new regulation, itâ€™s still important to highlight the capability of drivers and avoid stifling the appeal of the technology by unfairly penalising them.
â€œSetting the boundaries of driver and autonomous system liability will require a detailed understanding of how users interact with technology. Defining the parameters of handover is an important step in delivering the driverless experience which people will expect.” Chris Jackson, Head of Transport Sector, Burges Salmon
The latest report comes at a difficult time for the developers of autonomous vehicles. Ride-hailing firm Uber cancelled its self-driving vehicle tests in the United States after one of its vehicles was involved in a fatal collision. And Tesla is currently at loggerheads with Americaâ€™s National Transportation Safety Board over a fatal crash in March involving a Model X that was running in Autopilot mode.