Looking to prepare for the eventual reality of an autonomous-vehicle future, Ford partnered with Virginia Tech Transportation Institute (VTTI) to conduct a user-experience study to test a method for communicating a vehicle’s "intent" by soliciting real-world reactions to a self-driving car on public roads.
Additionally, Ford is working with several industry organizations to push toward creation of a standard, including SAE International and the International Organization for Standardization. The hope is that a common visual-communications interface most people can understand across all self-driving vehicles in all locations will help ensure safe integration into all global transportation systems. Ford said that as part of a separate work stream, it also is working on ways to communicate with those who are blind or visually impaired.
No driver? Not really
The study adopted a decidedly unique approach to "simulating" an autonomous vehicle: the Virginia Tech team developed a way to conceal the driver with a “seat suit," which creates the illusion of a fully autonomous vehicle with nobody in the driver's seat.
The illusion of no driver is necessary to test and evaluate real-world encounters and behaviors, according to the partners.
“Understanding how self-driving vehicles impact the world as we know it today is critical to ensuring we’re creating the right experience for tomorrow,” said John Shutko, Ford’s human factors technical specialist, in a release. “We need to solve for the challenges presented by not having a human driver, so designing a way to replace the head nod or hand wave is fundamental to ensuring safe and efficient operation of self-driving vehicles in our communities.”
As part of Ford’s efforts to ensure autonomous vehicles can safely share the road with humans, the joint research project set out to investigate lighting signals on the exterior of a simulated self-driving vehicle that communicate whether it is driving, yielding or about to accelerate from a stop. For that, Ford outfitted a Transit Connect van with a light bar placed high on the windshield.
Can lights replace human signals?
The researchers then went to work experimenting with three light signals to signal the communication of the vehicle’s intent: Yield is indicated by two white lights that move side to side, signifying a vehicle is about to yield to a full stop; Active autonomous driving mode, using a solid white light to indicate the vehicle is driving autonomously and Start to go, noted by a rapidly blinking white light to indicate the vehicle intends to accelerate from a stop.
Throughout August 2017, the simulated autonomous Transit Connect was driven on public roads in northern Virginia, which has a high-density mix of traffic and pedestrians, with researchers capturing video and logs of pedestrian reactions. More than 150 hours of data over approximately 1,800 miles of driving was collected in an urban environment, including encounters with pedestrians, bicyclists and other drivers. The van's light-bar signals were activated more than 1,650 times at various locations around Arlington, Va., including at intersections, parking lots, garages, airport roadways and various other locations.
Multiple high-definition cameras mounted in the study vehicle provided a 360-degree view of the surrounding area and recorded the reaction of other road users to what they believed was a driverless vehicle. According to the partners, this data will be valuable to understanding if other road users change their behaviors in response to self-driving vehicles and the signals they employ.
"This work is of value not only to vehicle users and manufacturers, but also to anyone who walks, rides or drives alongside autonomous vehicles in the future,” said Andy Schaudt, project director, Center for Automated Vehicle Systems, Virginia Tech Transportation Institute. “We are proud to support Ford in developing this important research.”
“Preparing for a self-driving future is going to take all of us working together,” Ford's Shutko added. “That’s why we’re developing and advocating for a standard solution so it can be adopted by the industry and applied to all self-driving vehicles.”
For a demonstration of the Ford Transit Connect simulated autonomous vehicle in action, visit https://youtu.be/EwujR1ARsog.