Connected Electric Autonomous Vehicles (CEAV)Developing a Safety Plan for Self-Driving Shuttles
December 16th, 2020
Autonomous vehicle pilots are an important part of the Smart Columbus portfolio. As the city of Columbus is the 14th largest city in the U.S. and home to diverse business and residential communities, autonomous vehicles, also called self-driving shuttles, fit into the landscape of smart mobility options being piloted in the region through Smart Columbus’ efforts.
After deploying a successful one-year pilot of the Smart Circuit in downtown Columbus starting in December 2018, with more than 15,000 riders, Smart Columbus launched its next self-driving shuttle pilot in Linden, a residential community.
Launching the Linden LEAP
The goal of the Linden LEAP is to pilot self-driving technology in a neighborhood setting while connecting residents to community resources and public transit. The shuttles were provided by EasyMile, an autonomous vehicle company based in France. EmpowerBus, a local microtransit provider, was contracted by Smart Columbus to provide operators and training. Of the 10 operators hired, seven live in or are from the Linden community.
In February 2020, two Linden LEAP shuttles launched in the community. The shuttle began seeing success in the community, allowing residents to get more food from the St. Stephens Community Center and have better access bus rapid transit line, the CMAX.
Like the launch of the Smart Circuit shuttle, Smart Columbus deployed 115 rigorous safety and operational tests and tabletop exercises with stakeholders. However, like with all technology, the shuttle faced challenges.
On Feb. 20, one of the Linden LEAP shuttles was traveling at 7.1 miles per hour and came to a sudden stop. As a result, one of the two passengers slipped from her seat to the floor and sought medical attention. Smart Columbus temporarily suspended operation of both Linden LEAP shuttles, pending further review. On Feb 24, EasyMile arrived on-location to initiate its review. On Feb. 25, the National Highway Traffic Safety Administration (NHTSA) suspended all U.S-based operations of EasyMile pending a safety evaluation. Upon review, EasyMile determined that a slight deviation in the steering of the shuttle, similar to the steering wheel slipping in a car, caused the sudden stop on Feb. 20.
Making safety and operational adjustments
Sudden stops in autonomous vehicles can be caused by a multitude of factors, including some that are not apparent to the eye. These can include objects, such as insects or exhaust from another vehicle being picked up by the shuttle’s sensors. Stops can also be caused when operating conditions conflict with safety chain requirements, a set of rules that need to be met in order to safely operate the shuttle. In the case of the incident on Feb. 20, the steering deviation didn’t fit within the established safety chain rules. The shuttles are programmed to stop when there is a discrepancy between the defined rules and current conditions. Factors including weight distribution and road conditions can affect the vehicle’s ability to meet the safety chain requirements and, therefore, stop.
As a result of these findings, EasyMile has made adjustments in its safety chain to modify the rules, within established safety limits, to reduce sudden stops. Columbus-based operators have also received additional training to proactively identify external factors that could cause a sudden stop and how to make adjustments to prevent them.
While these modifications will reduce the frequency of sudden braking, they will not prevent them, especially if the vehicle detects an obstacle in its path. All passengers should ride Linden LEAP with the understanding that the vehicle may unexpectedly stop.
EasyMile has worked closely with NHTSA to complete their safety evaluation. With input from Smart Columbus and the 10 other U.S. stakeholders operating EasyMile shuttles, EasyMile developed a Passenger Safety Enhancement plan. The plan details changes that need to be made before all U.S. shuttles can return to passenger service. These changes include:
- Audio alert reminding passengers the vehicle can make sudden stops
- Additional signage
- Additional operator training on safety,
- Alternative manual remote for the operator,
- Operator performance measuring, and
- Seat belts installed on all vehicles
Upon the implementation of these changes, EasyMile will submit a request for reinstatement to NHTSA before the Linden LEAP can return to passenger service.
Independent review of shuttle safety
Per our Safety Management Plan, Smart Columbus convened an independent incident review panel consisting of operational, technical and project management experts to review the incident and provide feedback. Based on their feedback, we’re making the following adjustments to our standard operating procedures, operator training, test plan and safety management plan:
- Install additional signs for riders to be aware of the potential for sudden stops
- Install signage that describes the passenger rights and rules
- Operators will limit the moving of the vehicle following an incident unless instructed to do so by supervisor or law enforcement
- If the vehicle needs to be moved following an incident, it will operate only in manual mode
- Operators will communicate information and next steps with passengers during an incident
- Additional simulated incident training for operator
- Additional validation vehicle testing
- Equip shuttle with regulation orange triangle signage to be placed on road to caution drivers about stopped vehicle ahead
Evaluating and preparing for the shuttle relaunch
Smart Columbus will follow guidelines set forth by the State and City regarding COVID-19 and those impacts on the Linden LEAP’s return to service. We will be regularly assessing based on the current state of affairs when it is prudent to return to service and continue piloting self-driving technology in a neighborhood to connect Linden residents to needed community resources. The safety of our passengers and the public will continue to be our top priority.
For the Linden LEAP to return to passenger service, the following will need to take place:
- Installation of NHTSA approved safety mitigations including signage and seatbelts by vendor
- A detailed plan provided by the vendor describing how Operator Performance Monitoring will be conducted
- Request for reinstatement will need to be submitted by vendor and accepted by NHTSA
- A new local operator will need to be brought on-board since EmpowerBus, the local mobility startup that provided operator service for the Linden LEAP, ceased business operations as a result of COVID-19 impacts
- Additional improvements to the safety management plan, standard operating procedures, and test plan will be implemented
Please visit lindenleap.com for service updates.
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