For years, NovAtel has developed safety critical systems for the aviation industry, where precise satellite measurement information is vital. Now the company is using the experience and knowledge gained in the aviation space to enter a new market—a market with even more stringent performance expectations and a need for positioning accuracy.
NovAtel intends to become the solutions provider that makes driverless cars a common sight on our roadways, providing the autonomous driving positioning reference. To that end, NovAtel formed a specialized Safety Critical Systems group in 2015 and tasked the new team of engineers with creating safe Global Navigation Satellite System (GNSS) positioning technology for driverless cars and autonomous applications in markets such as mining and agriculture.
The growing team is made up of engineers from a variety of backgrounds, including aviation, commercial, safety and automotive, said Jonathan Auld, NovAtel’s director of safety critical systems. All are talented professionals that he handpicked himself to take on this challenging task.
“This is not a trivial problem to solve. You can’t wave a wand over a product to make it safe,” Auld said. “You can’t take a product to the lab, do a test, and declare it safe. There are design considerations and engineer process considerations you have to take into account.”
Why is NovAtel interested in leading the way for precise positioning in this application market? It just makes sense, said Auld. The company is known for its high-precision products that deliver centimetre- and decimetre-level performance. Because of its reputation in the industry, clients who plan to move to autonomous vehicles began turning to NovAtel for a positioning solution that’s not only precise, but that also meets safety standards.
Car manufacturers, many of which use NovAtel as their reference positioning system, also wanted to know if NovAtel could achieve centimetre accuracy in driverless cars, while still meeting industry safety standards, necessary production volumes, and the required price point.
The simple answer is ‘yes,’ according to Auld. The team is already working on this groundbreaking initiative and leveraging what they learned during NovAtel’s participation in the Federal Aviation Administration (FAA) GPS Wide Area Augmentation System (WAAS) project, a Satellite-Based Augmentation System (SBAS) that evolved through three generations of certified GNSS receivers provided by the company.
Meeting stringent safety standards will mean a lot more time and effort will go into the product development process, Auld said, which takes a special type of team to successfully execute. They’re ready for the challenges that come with providing a safety-critical GNSS solution for the automotive industry, and, because of their experience with safety certification, they know what to expect throughout the process, from laying out the initial objectives to completing the final design.
A Different Process from the Start
From the very beginning, when developing a safety-certified product, engineers have to look at it differently than a standard commercial product, Auld said. Before they can even get started, “They must determine the safety goal of the system they are designing and how it integrates with other parts of the overall system.”
“You have to think about how it’s going to fit into the whole equation,” Auld said. “It starts from day one with setting the requirements and carries on from there. There are also additional steps that need to be taken throughout the development cycle. There’s mandated deliverables and procedures you have to execute—for example, failure mode assessment—that aren’t always completed during standard commercial development.”
Engineers must consider the different ways the system can fail, Auld said, and what will happen if it actually does fail or provide misleading information. For example, if a safety-certified receiver outputs a position, it also outputs a quality indicator. If the receiver says it’s accurate to one metre but is actually outside that envelope, it represents misleading information that could lead to problems—especially if you’re talking about driverless cars, which must be able to identify exactly where they are on the road at all times. This scenario is identified as hazard in the image below. Examples of safe failure and safe operation protection are also illustrated.
“These products have extra algorithms that predict and provide qualification on the position that’s coming out so that you know that it’s good or, conversely, so you know not to trust it because you can’t make sure it’s safe,” Auld said. “Both of those are equally important.”