Tokyo — Honda has set itself the ambitious goal of having zero collisions in its cars ten years from now, and hinges most of that safety improvement on adding active safety features that help prevent accidents, as well as Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I) technologies to give drivers more warning about their surroundings. We sampled some of the new ideas at a briefing at Honda’s R&D center in Japan.
The first new feature is Automatic Emergency Braking. Like similar systems from other automakers AEB sounds an alarm inside the cabin and can apply the brakes if a front-end collision is imminent. The system is aimed at reducing pedestrian fatalities and currently only works at speeds up to 37 mph, but it proved very effective in our brief test. We drove a test car fitted with AEB at a steady 31 mph toward a dummy of a pedestrian. As we approached, the car’s instrument cluster flashed a warning and produced loud chirping, then the system applied full braking power and stopped the car a few feet away from the pedestrian cutout. AEB brakes so aggressively that the tires chirped and the ABS system activated. We repeated the demo with another pedestrian cutout that was suddenly pushed out in front of our car, and AEB stopped the car equally well.
AEB uses input from a windshield-mounted camera and a millimeter-wave radar sensor in the car’s grille. That allows the car to determine the position, speed, and even direction of a pedestrian. The system can also prevent crashes with cars or other solid objects that are at least one meter (three feet) tall. Based on crash data from Japan, Honda estimates that AEB could prevent about 90 percent of all pedestrian fatalities caused by cars traveling 37 mph or slower.
Riding The Green Wave
Honda’s so-called Green Wave technology aims to promote safety and better fuel economy by providing the driver with directions on how to drive. Infrared transmitters on traffic lights transmit data to sensors in the car’s passenger window and dashboard, which interpret the information and display in on a screen mounted in the dashboard. Honda used IR technology rather than radio waves because many Japanese traffic lights already have IR transmitters, and the government plans to overall and expand the V2I transmitters within the next two or three years.
The first part of the Green Wave recommends a driving speed at which the car will reach the next traffic light when it’s green. In our test Japanese-market Honda Odyssey, this meant we traveled at 26 mph while a control car in the adjacent lane drove at about 35 mph. While the other car had to brake, stop at a simulated red light, and then accelerate again, we breezed through the fake intersection about five seconds after the light turned green. This is designed to promote smoother, more fuel-efficient urban driving, and to reduce the risk of rear-end collisions from frequent stop-and-go traffic. But it might frustrate other drivers who wonder why you’re driving so slowly.
Green Wave also lets drivers know when traffic lights will turn green, so they’re less likely to be rear-ended by impatient drivers. A series of five bars on the in-car screen counts down, until it displays “Confirm road ahead” and the traffic light turns green. Honda believes Green Wave could go into production in about two to three years.
Adaptive Cruise Control With Cut-In Prediction
i-ACC is Honda’s enhancement of adaptive cruise control, which benefits from a new feature called Cut-In Prediction. With normal adaptive cruise systems, the computer will brake aggressively and then subsequently re-accelerate when another vehicle changes lanes in front of the car. Honda’s system, by contrast, guesses when a car in an adjacent lane may move over and adjusts its speed pro-actively.
i-ACC uses a camera and radar to track up to six vehicles, and uses information like closing speeds between vehicles to determine which cars are likely to change lanes. Honda says Cut-In Prediction can react up to five seconds earlier than normal adaptive cruise control, keeping a safer distance between vehicles and also saving fuel by driving more smoothly. The front-facing camera can also be tasked with lane-departure warning and traffic-sign recognition duties. Honda showed a static demo of i-ACC in an Accord sedan, but didn’t allow us to test the system.