The present invention relates to a control device of a rearview mirror of a vehicle, and more particular to a control device for automatically adjusting a view angle of a rearview mirror of a turning vehicle. The present invention also relates a control method for automatically adjusting a view angle of a rearview mirror of a turning vehicle in response to an output of a navigation system such as an electronic compass or a global positioning system (GPS).
When a driver is seated in a vehicle, he should adjust all of the interior and exterior rearview mirrors according to his need. The rearview mirror can be adjusted manually or automatically by pushing buttons. After the adjustment of rearview mirrors is done, the view angle of each rearview mirror seen by the driver is constant, and it is difficult and also dangerous for the driver to further change the view angles while driving.
In practice, when a driver would like to change to another lane or turn to another direction, he will need to realize more about the situation of the adjacent lane to see whether there is any vehicle oncoming. For a simple plane mirror serving as the exterior rearview mirror, the view angle is not wide enough. Therefore, a mirror consisting of two sections is developed to solve this problem, as shown in FIG. 1. The two sections, for example, may be two plane mirrors 11, 12 deflected from each other (FIG. 1A) by a fixed angle, or one plane mirror 13 and one curved bump 14 (FIG. 1B). This kind of rearview mirror, although improves the view angle to some extent, still has the following disadvantages. First, the manufacturing and assembling processes of the two-sectional mirror are complicated. Further, the outer section of the mirror is generally small, so it is uneasy for the driver to watch it clearly, especially for the mirror at the passenger""s side.
In order to solve this problem, it is desired that the view angles of the rearview mirrors can be automatically adjusted in order to avoid any blind spot. For example, when the vehicle is turning right, it is desirable that the driver clearly sees the right lane by rotating the exterior rearview mirror at the right side of the vehicle outwards. Further, it is more preferred that the rotating angle of the rearview mirror depend on the turning angle of the vehicle.
Therefore, an object of the present invention is to provide a control device and method, which can adjust the view angle of the rearview mirror automatically while the vehicle is turning.
Another object of the present invention is to provide a control device and method, which can adjust the view angle of the rearview mirror dynamically according to the turning angle of the vehicle.
A first aspect of the present invention relates to a control method for automatically adjusting a view angle of a monitoring device of a turning vehicle. The method includes steps of receiving an output of a navigation system; determining a turning operation of the vehicle according to the output of the navigation system; and triggering the monitoring device to move in response to the turning operation of the vehicle. Preferably, the movement of the monitoring device is adjusted dynamically. In other words, it is preferred that the method further includes a step of determining a turning level of the turning operation, and the monitoring device is triggered to move to an extent corresponding to the turning level. The monitoring device, for example, can be an exterior rearview mirror and/or a charge-coupled device (CCD) camera.
When the navigation system is an electronic compass, the turning level of the vehicle can be determined by comparing the output of the electronic compass with a preset value. Therefore, it is preferred that the receiving, comparing and triggering steps are repeated to dynamically adjust a view angle of the rearview mirror of the vehicle.
Preferably, the control method further includes a step of counting a time period to determine the preset value. The time period is accumulatively counted when the turning level is kept to be zero, and the time period is counted over whenever the turning level is determined to be non-zero. In an embodiment, the output of the electronic compass is indicative of one of sixteen direction zones, the preset value is indicative of one of the sixteen direction zones, and the turning level is determined to be zero when the output of the electronic compass and the preset value indicate the same direction zone. The output of the electronic compass replaces for the preset value to serve as a new preset value, and the rearview mirror is triggered to be restored to its initial position when the counted time period exceeds a predetermined value, e.g. 2 seconds.
Preferably, the turning level correlates to an angle between the direction zones indicated by the output of the electronic compass and the preset value.
In another embodiment, the navigation system is a global positioning system (GPS). The turning level correlates to a predetermined turning angle under the guidance of the GPS. The control method further includes a step of triggering the rearview mirror to be restored to its initial position when the GPS indicates the completion of a turning operation by the predetermined turning angle.
A second aspect of the present invention relates to a control device for automatically adjusting a view angle of a monitoring device of a turning vehicle. The control device includes a microprocessor which repetitively receives an output of the navigation system, determines a turning operation of the vehicle according to the output of the navigation system, and triggers the monitoring device to move in response to the turning operation of the vehicle. Preferably, the movement of the monitoring device is adjusted dynamically. In other words, it is preferred that the microprocessor further determines a turning level of the turning operation, and the monitoring device is triggered to move to an extent corresponding to the turning level.
A third aspect of the present invention relates to a control device for automatically adjusting a view angle of a rearview mirror of a turning vehicle in response to the output of a global positioning system (GPS). The control device includes a microprocessor electrically connected to the GPS and a controller area network (CAN) bus. The microprocessor monitors the output of the GPS. When the output of the GPS indicates that the vehicle arrives at a predetermined turning position, the microprocessor sends out a digital encoding signal to a rearview-mirror actuating device via the CAN bus to trigger the rearview-mirror actuating device to rotate the rearview mirror. The rotation of the rearview mirror is preferably dynamically adjusted.
A fourth aspect of the present invention relates to a control device for automatically adjusting a view angle of a rearview mirror of a turning vehicle in response to the output of an electronic compass. The control device includes a microprocessor electrically connected to the electronic compass and a controller area network (CAN) bus. The microprocessor monitors the output of the electronic compass. When the output of the electronic compass indicates that the vehicle is heading a direction different from a preset direction, the microprocessor sends out a digital encoding signal to a rearview-mirror actuating device via the CAN bus to trigger the rearview-mirror actuating device to rotate the rearview mirror. The rotation of the rearview mirror is preferably dynamically adjusted.
Preferably, the control device further includes a timer electrically connected to the microprocessor for counting a time period, wherein the direction that the vehicle is heading replaces for the preset direction to serve as a new preset direction when the counted time period exceeds a predetermined value.