Toyota’s latest safety technology may be of greater interest to those outside the vehicle than the passengers in it. Based on our initial impression, from a demonstration by the automaker, the Active Pedestrian Detection System adds a significant element of safety, but it would benefit from further refinement.
Like similar systems from Mercedes-Benz and Volvo, the Active Pedestrian Detection System is designed to help avoid hitting a pedestrian and to minimize injuries by stopping or slowing the vehicle, if the driver does not react in time.
Where Toyota says its system differs from some others on the market is in its use of radar in addition to a camera system to monitor the road ahead. And that, they say, makes it more effective at night, when many such accidents occur.
To demonstrate the system, the traveling road show included a Lexus LS 600h so-equipped, along with a "walking" pedestrian dummy named Steve and a gantry used to suspend and transport him into harm’s way.
In the course of several passes at various speeds, the Pedestrian Detection system performed with mixed results. Sometimes, the Lexus stopped with room to spare, letting Steve saunter along as oblivious as an ear-budded New Yorker. Other times, he ended up splayed on the pavement, reduced to a pile of parts.
While the system does not promise to bring the car to a complete stop at speeds greater than 24 mph (40 kmh), the Lexus failed in its first demo at just 10 mph. Both the system and Steve faired better in subsequent runs. In two runs at 25 mph, the Lexus stopped in time only one of the two passes, reflecting that the system was operating at its limits. When the car braked in time, stops were anything but smooth, with some tire lockup and jerky stops that seemed to mimic a panicked driver standing on the pedal.
In comparison, a Mercedes-Benz demo with an S550’s Pre-Safe system last year produced flawless results, with a series of modulated, drama-free halts.
The system added a clear safety margin, protecting both the car and pedestrian, and it will at least scrub off some speed to mitigate injuries even when the car is unable to come to a complete stop. But the demonstration reminded that, for now, such active systems are not a replacement for an attentive driver.
Toyota says its Active Pedestrian Detection System is still subject to ongoing development, although it is available now on the Lexus LS L and hybrid models. Bundled with Lane Keep Assist and other features, the system is part of the Advanced Pre-Collision System Package and adds $6,500.
We applaud the efforts automakers are putting into these important safety systems and remain impressed with the rapid proliferation and increased sophistication we’re seeing in general. But the LS demo reinforces the notion that drivers need to be fully focused on the task at hand and not rely 100 percent on extra safety aids. We’re guessing that would be Steve’s advice, as well.
Copyright © 2005-2014 Consumers Union of U.S., Inc. No reproduction, in whole or in part, without written permission. Consumer Reports has no relationship with any advertisers on this site.