Cycle Safety Shield Forward Colision Warning (FCW)
Rear-end accidents are the most common accident types. The importance of keeping sufficient headway for reduction of accidents is recognized by traffic authorities worldwide and is being enforced in an increasing number of countries. Even when sufficient headway is kept a momentary lack of concentration can lead to a situation where a rear-end collision can occur. Cycle Safety Shield`s Vision-only Vehicle Detection provides a Forward Collision Warning (FCW) in situations where the host vehicle is approaching a preceding vehicle with a high closing rate. This FCW alerts the driver of the critical situation and therefore can prevent or mitigate an accident.
The Forward Collision Warning system is based on Mobileye’s core Vision-only Vehicle Detection technology and provides the driver with a warning in critical situations where a collision is imminent (within up to 3.0 seconds)
Forward Collision Warning detects whether a crash is imminent by computing the ‘Time To Contact’ (TTC) taking into account host vehicle speed, relative speed and relative acceleration. The latter are measured using change of the image size of the target (scale change). In case of a predicted crash, a ‘critical’ warning is given to the driver.
The FCW collision warning ‘track’ can also be used as a trigger message to other vehicle systems to provide pre-crash functionality, such as: secondary restraint system pre-conditioning or brake pre-fill.
Cycle Safety Shield`s FCW algorithm also takes into account specific scenarios where the system is expected by the driver to have different sensitivity. Such scenarios include the following cases:
• The vehicle in front is standing still – in this case there is a major advantage in using a vision sensor which does not require the target to be moving in order to be acquired. In many cases this is a constant speed scenario with a high closing rate. A warning can be given up to 3.0 seconds before a possible impact.
• The vehicle in front is braking – the braking is first detected by recognizing the target vehicle’s brake lights. This is an acceleration scenario with a lower closing velocity. In this case a warning can be given up to 7 seconds before a possible impact.
• The driver is already pressing the brake pedal – in this case the warning can be given a little later as the drivers response time may be reduced as the brake pedal is already depressed and the time to avoid the collision can be shorter. On the other hand it is important to provide the driver with an alert also at these cases because in such conditions the driver may not notice the slow drift. It is a backup mechanism to alert the driver that the danger has not yet passed.
Cycle Safety Shield Urban Forward Collision Warning (uFCW)
As a natural extension to Cycle safety shields FCW feature, the uFCW allows operation of the Forward Collision Warning System also at low speeds. While the main goal of FCW is to save lives, uFCW – by virtue of its low speed environment – seeks to reduce the incidence of non-fatal ‘fender bender’ accidents.
This scheme uses the concept of a ‘virtual bumper’ which adds a ‘buffer zone’ on top of the known physical bumper location to allow a more appropriate warning scheme to be implemented at the close range. Cycle safety shield is making use of additional vision cues, such as license plates, when driving at close range.
Cycle safety shield Headway Monitoring and Warning (HMW)
Traffic authorities worldwide have recognized how important keeping sufficient headway is to preventing collisions on the road. In fact, many countries have made safe headway keeping law.
Cycle safety shield AWS and C2 products all have Headway Monitoring and Warning (HMW) as a core feature.
Headway is defined as the time it will take to reach the current position of a vehicle driving ahead, and is calculated by dividing the distance to the vehicle ahead with the travel speed of the host vehicle.
The Headway Monitoring Warning system is based on Cycle safety shields series level Vision-only Vehicle Detection system, which operates in all light and weather conditions, and recognizes the preceding vehicles in the host vehicle’s lane and adjacent lanes and provides accurate range estimation for the targets. Cycle safety shields threat assessment identifies the Closest In Path Vehicle (CIPV) and from it s range and current speed the headway estimation in Seconds is derived. The HMW feature level notifies the driver of the current headway and provides a warning should a preset threshold be passed.
As with all Cycle safety shield features, HMW works in all weather and light conditions.