YPSILANTI, MI — The specially equipped demonstration car moves slowly through the tight, winding course carved out by a series of orange traffic cones stationed around an empty lot here at the American Center for Mobility proving ground.

The track is just slightly wider than the car itself, but the vehicle is traveling only at about 5 mph (8 km/h). Normally, driving at such a low speed would make it fairly easy to avoid mowing down one of the cones.

But here’s the rub: there’s no opportunity to see in or out, as windshield and all other glass in the vehicle is completely covered. The only way to successfully steer through the course is to pilot a digital rendering of the vehicle along the route displayed on a video screen mounted just above the steering wheel.

Despite all that, our uninitiated driver maneuvers through the slalom without a hitch – no cones are toppled or crushed along the course that takes several minutes to complete – thanks to the extremely precise, satellite-fed positioning data used to guide us along the correct path.

The demo, put on recently by Swift Navigation in conjunction with a Society of Automotive Analysts panel discussion on the scaling up of safe autonomous driving, is meant to prove how wider use of more-precise Global Navigation Satellite System (GNSS) technology may be one of the critical missing pieces needed to make fully autonomous vehicles a reality.

Precision GPS, as this next-level GNSS is commonly known, represents an exponential leap in positioning accuracy from today’s more conventional GPS technology. Whereas today’s more ubiquitous base-level GPS technology can track a vehicle’s position to within a margin of error of about 6-30 ft. (2-10 m), Precision GPS can place the car within less than a few inches of its actual location.

The gap in precision would have made a significant difference in our test run. Had the demo car been relying on standard GPS data in our test run, many cones would have been knocked down as the vehicle weaved its way along the route, as the driver would not have been as accurately informed of its actual position on the makeshift road.

Such vague positioning would be a disaster for AVs expected to travel on their own over a variety of roads while facing a wide range of traffic conditions.

One of the reasons standard GPS is less accurate is that signals coming from space can be distorted by the satellite’s imperfect orbit, the atmospheric conditions the signal must pass through and other factors. The Swift Navigation technology, dubbed Skylark, relies on those same satellites but employs a widespread network of substations to collect that data and then uses its proprietary software to correct for any distortions. That cleaned-up data ultimately is then accessed by the vehicle to zero in its global positioning.

“It’s been a tough mathematics problem to solve,” Swift’s James Tidd, vice president of systems engineering, says of the target of plus or minus less than 3 ins. (3-7 cm) promised by Swift’s Skylark service. “But we think we are hitting the metrics (we’ve set).”

While the demo vehicle is packed with hardware in its cargo bay, adding the Skylark technology requires no components not already found on today’s vehicles, and the software needed takes up little bandwidth, Tidd says, meaning automakers won’t have to wait for next-generation software-defined-vehicle architectures and high-powered computing for this to work.

Such ease of implementation is essential to developing the future of autonomy, experts say.

“We have to make use of components already in place on existing vehicles, so (any solution) has to be integrated with the vehicle as is, just a software update, and the technology has to be available worldwide,” panelist Daniela Steinbacher, program director for German supplier Bosch, says of what it will take to get automated driving to the next level of adoption.

Precision GPS perfectly complements other technologies required to make autonomous vehicles safe and reliable, panelists say. Today’s sensor suite of radar, lidar and cameras work well where GNSS doesn’t, such as in a tunnel or parking structure, but GNSS outperforms sensors where they are weak, such as in low light conditions, in inclement weather and along featureless landscapes that sensors have difficulty defining.

In working together, onboard computers can switch back and forth between reliance on the sensor and GNSS data every 50 milliseconds to ensure a vehicle stays on path, says Curtis Hay, technical fellow-Vehicle Location for General Motors.

And because High Precision GNSS is a fairly low-cost solution to taking today’s advanced driver-assistance systems to Level 3 (hands off/eyes off highway) autonomy and beyond, it has potential for application in privately owned vehicles, not just commercial and mobility-service fleets, opening the way for higher-volume application.

Swift says it has access to 100-plus satellites and a dense network of ground stations, typically numbering in the hundreds to cover a single continent-sized market, to collect the data. That assures availability of its service 99.9% of the time, a performance rate the San Franciso-based tech firm believes gives the company an edge over its competitors.

AV advancement hit a development wall in the last few years for several reasons, panelists say, primarily because the technology solution has proven far tougher to come by than engineers envisioned.

“The business case stalled,” points out Mark Barrott, a partner at Plante Moran, who says his consultancy once predicted nearly every automaker would have AV technology on the road by 2024. Today, it lists just a handful of players it expects to have AVs running in significant numbers by the end of this decade.

“It became increasingly apparent what a massive technology challenge it was,” Barrott says of the industry’s AV-development retreat.

“There’s a big jump required in validation to Level 3 autonomy,” Steinbacher acknowledges.

The lingering question is when – or whether – consumers will want to pay for advanced auto-pilot features on their personal cars and more and more mobility-service customers will feel comfortable riding in the back of driverless cabs. But panelists believe Precision GPS’ ability to help a vehicle remain locked on course will help sway consumers in the right direction.

Swift won’t reveal which automakers it currently is providing its service to or working with on future programs, but the panel that included executives from GM and Bosch suggests those two companies may be among them.

“Seventy percent of (the global automotive brands) are using it or have it planned for model years ’27, ’28 and ’29,” Tidd says of Precision GPS. “Another 20% are evaluating it. The other 10% are missing out, in my opinion, or just not looking at the advanced use cases (this would support). So it has a very high adoption rate.”

Swift says on its website it so far has been awarded programs covering more than 10 million ADAS-enabled and autonomous vehicles worldwide, meaning its version of the technology is on the verge of reaching full commercialization scale.

For higher levels of autonomy to take hold “we need standardization,” Steinbacher says in support of wider Precision GPS deployment. “We can’t have everyone doing their own thing. Level 3 (autonomy) will cost so much more if (companies are) doing everything on (their) own.”