Pedestrian Detection More Crucial in AEB Systems
April 14, 2020—Recently, the Insurance Institute of Highway Safety (IIHS) announced that four automakers have met a 2016 commitment to incorporate automatic emergency braking (AEB) systems into their new model year vehicles. So far, four automakers have incorporated AEB into their fleets—Tesla, Volvo, Mercedes-Benz and Audi.
While approximately 11 automakers have made progress towards the commitment, David Zuby, executive vice president and chief research officer for the IIHS, says there are currently no plans to modify the commitment.
However, he says the IIHS research in the years since 2016 has shown that not only do AEB systems help reduce crashes, but AEB systems with pedestrian detection help save more lives.
Percent of Vehicle Series with Pedestrian AEB:
Standard Optional Not Applicable
2019 35% 21 % 43 %
2020 51 % 15 % 34 %
Due to the safety implications, Zuby says the IIHS is promoting automakers to fit their vehicles with the safety feature. In order for OEs to receive a top safety award from the IIHS, the vehicles must have an AEB system that is pedestrian-detecting.
According to AAA's Automatic Emergency Braking with Pedestrian Detection report from October 2019, 56 percent of 2018 model year cars come equipped with automatic emergency braking with pedestrian detection as either standard or optional equipment. These systems will warn the driver through an audible, visual or haptic alert when it determines a crash risk exists.
AAA tested vehicles with pedestrian detection systems at speeds of 20 mph and 30 mph. The results were that the effectiveness of the systems was vehicle specific.
The Sensors that Pedestrian Detection Systems Use
According to AAA, here are the four types of sensors AEB with pedestrian detection uses.
Most ADAS such as forward collision warning/mitigation, adaptive cruise control and lane keeping assistance use the same sensors. For example, current pedestrian detection predominantly relies on inputs from radar and image sensors.
- Radar: Generated radar waves are reflected by solid objects back to the sensor. Object attributes like distance, position, velocity and shape are determined. The advantages of using radar for these systems include functionality through most weather conditions like fog and snow. Radar sensors can usually be integrated behind plastic grills and bumper, allowing engineers more room for design.
- Image Sensors (Cameras): Cameras detect visible light within the EM spectrum and convert the input into digital code. Cameras are a popular addition because they have a low cost and are durable. Cameras can evaluate the driving environment in short or long distances and it is possible to create a 360° view around the car.
- LiDAR: Lidar sensors measure distance to objects by emitting infrared radiation and evaluating the reflected energy.LiDAR can measure object velocity and create high-definition maps of the environment. lidar resolution can allow for object classification and lane marker detection with accuracy currently approaching that of high-quality image sensors. However, liDAR sensors are sensitive to precipitation and fog.
- Ultrasonic Sonar: This sensor is typically integrated into parking assistance systems. It has an effective range of 20 feet or less.
The Crash Tests Involving Pedestrian Detection
According to the IIHS, the pedestrian autobrake test is the fourth crash avoidance evaluation in the institute's safety tests.
- IIHS began rating front-crash prevention systems in 2013.
- IIHS began rating headlights in 2016.
- IIHS began rating rear crash prevention systems in 2018.
In the new tests, vehicles are rated as basic, advanced or superior. The crash tests involve testing how well the car detects and mitigates a crash with pedestrian dummies.