Just a few years ago the only course of action for a driver faced with a pedestrian in his path would be to stamp on the footbrake, wrench the steering wheel and hope for the best.
Successive advances in braking technology, such as ABS, emergency braking and brakeforce distribution have increased the chances of avoiding impact. While these have become standard features of today’s mainstream cars, Toyota achieved a step-change in preventive safety with the introduction of its Pre-Collision System. This uses radar detection to spot pedestrians and other hazards, by and day by night, and initiate alerts and automatic braking to cut the risk of an accident.
Toyota has now added an extra dimension to this technology with automatic steering, a feature it believes will help prevent collisions in cases where automatic braking alone is insufficient, for example when the vehicle is moving too fast, or a pedestrian steps suddenly into its path.
PCS uses an on-board sensor to detect a pedestrian in the vehicle’s path. If it determines there is a collision risk, it triggers a warning light on the dashboard, immediately in front of the driver; if the likelihood of an impact increases, it sounds an alarm to warn the driver to take avoiding action and initiates pre-collision braking force and automatic braking.
If the system detects that a collision cannot be avoided by braking alone, and there is sufficient room for avoidance, it activates steer assist to direct the vehicle away from the pedestrian.
In 2012 Toyota introduced the system with increased pre-collision braking force and automatic braking in the Lexus LS 600h. It aims to make the technology more affordable and more widely available in its model ranges by 2015, prior to bringing the PCS with Pedestrian-avoidance Steer Assist to the market.
Toyota has also developed a next-generation advanced driving support system – Automated Highway Driving Assist (AHDA) – designed to support safer highway/motorway driving.
The system links two driving technologies to help secure safer driving and reduce the workload on the driver: Co-operative-adaptive Cruise Control, which communicates wirelessly with vehicles ahead to maintain a safe distance; and Lane Trace Control, which helps steer the vehicle on an optimal driving line within a traffic lane.
Toyota recognizes that it is important for the driver to be in ultimate control of a vehicle, so its intention is to introduce AHDA and other advanced driving support systems with which the driver remains in command, and there is no compromise in driving pleasure. It proposes to market AHDA from the mid-2010s together with other systems that can make driving safer and more secure.
Toyota presented its new technology at the Intelligent Transport Systems World Congress in Tokyo, and began road trials on Japan’s Shuto Expressway from 15 October.
Co-operative Adaptive Cruise Control: unlike standard radar cruise control which uses millimeter-wave radar to detect other vehicles, Co-operative Adaptive Cruise Control uses 700-Mhz band vehicle-to-vehicle ITS communications to acquire acceleration and deceleration data from the vehicle ahead. This allows the speed of the following vehicle to be adjusted accordingly and better maintain an appropriate distance. By reducing unnecessary acceleration and deceleration, it improves fuel efficiency and helps reduce traffic congestions.
Lane Trace Control: Lane Trace Control features brand new Toyota automated driving technologies. It uses high-performance cameras, millimeter-wave radar and control software to keep an optimum, smooth driving line within a traffic lane at all speeds, adjusting the vehicle’s steering angle, driving torque and braking force when needed.
