Autonomous Vehicle Hopes Hinge on Crash Avoidance Technology
The Importance of Redundancy
The apparent rivalry between lidar and camera-based technology has become heated enough that Elon Musk has described lidar as “a fool’s errand,” and anyone relying on the technology as “doomed.”
Tractica’s Kirkpatrick said ultimately such claims and debates about which technology is better to overlook a more grounded reality: Most present-day autonomous vehicles use a mix of technologies for collision avoidance, and that could continue to be the case for at least the near future.
This is made possible with the help of sensor data fusion, the popular IoT concept that Tractica’s Kirkpatrick described as “the idea of taking data from all of these disparate sensors and systems, and trying to make sense of all that.” This is done by algorithms that can weight different data points, and analyze and process them to “ascertain, for example, if lidar is telling us that there is some sort of object that is some feet away on the road. We may need another technology to tell us what that object is, and how the vehicle should react,” he added.
Whereas lidar paints a comprehensive 3D view of objects in the driving environment, cameras can identify those objects. Each may perform more or less accurately depending on weather or lighting conditions, or the guidance required for navigational functions. Other technologies may also contribute to the sensor data mix, such as traditional radar, which can sense objects at a greater distance than either lidar or computer vision, or GPS, which in some cases may provide the best fix on a vehicle’s location.
While companies like Velodyne and TuSimple are firm in arguing the advantages of their respective technologies and the disadvantages of others, they seem to buy into this notion.
As TuSimple’s Sun said, “We believe that lidar is important. We believe in sensor fusion. We have cameras all around the vehicle, and we also have lidar, radar and GPS on the vehicle, so all of the sensors give us really good input for understanding the environment around us. All kinds of sensors have limitations, but mastering the art of using the best of the sensors and the echoing of information will give us the best implementation.”
She added that while in TuSimple’s view lidar “has a limitation when it comes to rain, it also gives us a very good 3D view of the world. Some of our cameras are on the truck’s rooftop, but lidar gives us a good view from the ground up,” Sun said. “If a company can make good use of all the sensors that are available in the market, they have a good path to success.”
Velodyne had a similar take, as its spokesman said via email, “Sensor redundancy is an asset for autonomous vehicles. Building vehicle systems with sensor suites that include lidar along with other sensor technologies enables the strengths of each type of sensor to be optimized for the various use cases.”