This invention relates in general to motor vehicle lighting safety systems, and more particularly related to turn signals.
Motor vehicles sold in the United States are required by law to have a turn signal system such that a driver of a motor vehicle is able to signal intentions of an impending turn to other drivers. By activating a left or right turn signal via a hand operated lever, the driver is communicating directional intentions and thus is reducing the risk of a collision. The turn signal is an important safety feature that serves to prevent countless accidents each year. Appropriate turn signal usage makes an important contribution in attaining effective crash avoidance and passive safety. Usage of turn signals is required by law in virtually all jurisdictions, but the use of the turn signal in a motor vehicle is a voluntary act that is left to the discretion of the driver. Therefore, while all vehicles have the turn signal feature, diligent and proper use of turn signals is left solely to the driver's physical activation of the turn signal in appropriate situations as he or she would see fit.
Due to the voluntary nature of turn signal activation, it is therefore logical to conclude that proper usage of turn signals by all drivers in all locations would be less than 100%, assuming that driver neglect is the root cause. Other secondary causes of turn signal non-use would include various in-vehicle distractions which are greater in number now than in the past and cause a compromise in a driver's attention and contribute to turn signal neglect. Another contributor to turn signal neglect relates to marked dedicated turn lanes at intersections. Many drivers in specified turn lanes may not necessarily feel compelled to use a turn signal. This action may be rationalized by the driver since the vehicle is in a turn lane and may have an intersection traffic turn light, thus it is thought that other drivers already know his or her intended path. It remains important that the vehicle still use the appropriate turn signal in these situations, but commonly, they are not used. Additionally, turn signal non-use is still a violation of most local laws in these situations. Ideally, 100% compliance for all drivers would be the goal. In order to effectively reduce accident rates on a large scale, it would be desirable to have a system that would remedy a driver's neglect with regards to turn signal usage. The hypothetical perfect automatic turn signal system would be one that would accurately anticipate a pending vehicle turn a distance of a few hundred feet before the driver-intended turn and activate the correctly anticipated left or right turn signal at the appropriate point every time. However, no known practical automatic turn signal activation systems as such have been developed or are offered for sale. Unfortunately, this system would be highly complex, if at all possible given current technology and would literally involve a form of mind reading to anticipate the very thoughts of the driver. That is to say, such an automatic system could not know with certainty for instance, if a vehicle is going to turn left, turn right or go straight when approaching a simple four way stop intersection.
There are several cases of relevant art that teach automatic activation of turn signals at the point when a vehicle turn is initiated. These generally teach of an automatic activation that would indeed turn on the turn signal at the onset of a turn, and subsequently shut off the turn signal at the completion of the turn, based on a measured position of the steering system. This general method however, would not communicate the driver's intentions of a turn until the turn has begun, and thus would not adequately forewarn other drivers of a pending turn with sufficient time or travel distance. Additionally, these systems could not adequately distinguish a turn from a simple curve in the road. It is conceivable therefore, that turn signals of this type would be turning on and off in a seemingly random manner merely by steering the vehicle. This method would be considered an uncontrolled nuisance to all drivers and is likely the main reason these automatic systems are not in production. Other variations on automatic turn signals use other methods for automatically triggering turn signals, but these are not considered reliable or practical. None of these types of systems achieve the goal of consistently actuating the turn signal to effectively communicate the driver's intentions. Automatic turn signal activation systems like these described would not likely meet turn signal requirements as prescribed by the United States Government's National Highway Traffic Safety Administration and therefore would not be legal to sell as part of a vehicle turn signal system, nor would they satisfy laws regarding turn signal usage.
Alternatively, increasing turn signal usage amongst drivers might be achieved with increased enforcement of existing turn signal laws, but this effort would not be a widespread practical usage of law enforcement personnel and resources.
The types of prior art cited have surfaced over a long period of time and would serve to establish that there is a need for an improved system resulting in increased appropriate usage of turn signals. What is needed therefore is a practical, cost effective system residing within the vehicle whereby the driver who repeatedly neglects to use turn signals is effectively self-motivated to use turn signals such that usage approaches 100% over time, yet this system would not be a nuisance to drivers who consistently and appropriately use turn signals.