Speed limits and driving conditions along any given route may change frequently, particularly in urban settings. In addition, along a given route speed limits may change according to the time of day, such as during school hours or rush hours. The current and accepted method of informing the driver of the speed limit is through posted speed limit signs on the side of the road. However, it is easy for drivers to become distracted and not notice changes in speed limit sign postings. In addition, drivers may intentionally or unintentionally exceed the posted speed limit. Exceeding a posted speed limit can have negative consequences such as personal injury, property damage, and fines from speeding tickets. Moreover, when multiple speed limit signs are posted for a single section of road (e.g. a day speed limit and a night speed limit), a driver must determine which speed is applicable.
Several systems have been developed to warn drivers about exceeding the posted speed limit. Most of the current systems are based on the use of a Global Positioning System (GPS) receiver that determines the position of the vehicle and compares it to the posted speed limit by searching a centralised database. U.S. Pat. No. 6,515,596 from the Assignee is an example of such solutions and is incorporated by reference herein particularly for the description of the GPS communication protocol.
While such system provides alternative to posting speed limit signs, it is oriented as a reporting system and not as an reacting system to adjust the speed of the vehicle to the posted speed limit.
Adjusting the speed of a vehicle has been described for example in U.S. Pat. No. 6,462,675 from the Assignee by activating a speed controller. A driver may include a preference for a speed controller application to automatically govern the speed of the vehicle when excessive speeds are detected.
While this patent provides an additional feature of controlling a vehicle speed limit, such system is operating when a posted speed limit is exceeded.
However, there is no known solution to audit the behaviour of a driver to comply to an upcoming speed limit. Anticipation of an upcoming speed limit would leave him with the possibility to comply smoothly to the upcoming posted speed limit. Additional automatic adjusting of the speed would also be made in a progressive manner.
Therefore, in view of the foregoing, a need exists for a method, system and program for alerting a driver of upcoming speed limits and for adjusting the speed of the vehicle in case of non compliance to the warnings.
Moreover, it would be desirable that the cost of implementing such system would not be prohibitive. The present invention offers such low cost solution by working with the existing transportation infrastructure.