Autonomous trucking technology company Plus (formerly Plus.ai) has filed a safety self-assessment report describing its approach to putting self-driving big rigs on the road even as concerns persist about the usefulness of the voluntary reports in determining the safety of a given autonomous system.
The 34-page document from Plus, released on Thursday, comes a few months before the company’s Level 3 automated driving system starts mass production in China.
Level 3 trucks can make informed decisions for themselves, such as accelerating past a slow-moving vehicle, but still require human drivers.
Generally speaking, the report suggests a measured, incremental approach to the company’s eventual launch of fully autonomous trucks, known as Level 4. Two key metrics define that approach, according to Plus.
The first involves developing a self-driving system that leads to a reliable product: specifically a truck that is capable of driving the so-called “middle mile,” from hub to highway and back to another hub.
The second highlights Plus’ benchmark for safety: “Before taking the driver out of the vehicle,” the report states, “we need to prove that our system is safer than a human-driven truck.”
Plus doesn’t pull any punches in terms of what that means in concrete terms: “Billions of real road miles” will be needed, the report states, “to statistically prove the safety of the system before making fully driverless trucks commercially available.”
Voluntary reports under scrutiny
The National Highway Transportation Safety Administration’s (NHTSA) automated vehicle guidance contains 12 relevant safety elements for testing, and the federal agency encourages AV companies to submit safety self-assessments based on these areas.
To date, 24 self-driving vehicle companies have submitted the self-assessments, including companies that, like Plus, aim to automate long haul trucking: TuSimple, Kodiak, Waymo and Ike.
These assessments are interesting and some are fairly detailed in terms of showing how the company determines safety, said Michael Ramsey, a connected-vehicle analyst with Gartner.
“But in truth they are more like marketing documents than a detailed engineering analysis,” Ramsey told FreightWaves, “and there is no common standard for safety between the companies.”
Assuming the assessments are intended to identify companies that have done everything necessary to be safe, he said, “every report needs to be the same, and pass tests that are linked to real and verifiable data.”
That assessment and conclusion aligns with that of the National Transportation Safety Board (TSB), an independent agency and persistent critic of existing voluntary federal guidance on AVs.
How can you “determine the adequacy of risk and mitigation strategies,” asked Ensar Benic, a TSB project manager, speaking during a panel discussion this summer at the Automated Vehicles Symposium, “since there are no standards and assessment protocols.”
Redundancy and more redundancy
Responding to those concerns, Shawn Kerrigan, Plus COO and co-founder, said the report is simply one document that helps provide an overview of a company’s approach in developing their automated vehicle system.
“The real question those critics seem to be asking is — how do we know that the self-driving system works safely as the company reports?” Kerrigan said in an email to FreightWaves.
Citing a recent agreement with the Transportation Research Center, a well-regarded vehicle testing and proving ground, to test the Plus system using a variety of real-world scenarios, Kerrigan said the startup’s “pursuit of independent testing and certification is the best way to provide the public that reassurance.”
A systems approach
The Plus report appears to qualify as one of the more detailed submissions, showing how safety is embedded across its corporate culture, engineering process, operations and hardware choices.
That comprehensive approach dovetails with a systems approach to safety, a top-down, organizational methodology that is becoming the standard among AV companies following the deadly crash involving an autonomous Uber vehicle in 2018.
Kerrigan called out as one of key takeaways in the report Plus’ continued expansion of the so-called Operating Design Domain (ODD), the region and conditions in which the system is expected to operate safely.
In addition to continually expanding the ODD, Plus has implemented a “checker” to ensure the conditions meet the ODD, and if they don’t, to transition the system to a safe state, i.e., a redundant system or a manual driver.
“Every Plus feature includes a structured ODD definition and a set of tests for determining whether the operating conditions meet the defined ODD,” Kerrigan said.
Cybersecurity, perception systems and driver training are among the other topics covered in the report.