Patent Description:
This section provides background information related to the present invention which is not necessarily prior art.

A driver of a vehicle should have awareness of the surrounding environment to maximize safety. Vehicles require headlights for improving visibility at night. Further, various other types of electronics such as radar may also be used in a vehicle to improve and sense various conditions.

Certain vehicles such as motorcycles have a frame that moves relative to the road. That is, a motorcycle operator leans the frame of the vehicle during a turn. Because headlights and sensors are mounted to the vehicle or frame, the direction of the lights and sensors is also oriented in a sub-optimum position during leaning. For example, a headlight may illuminate the actual road directly in front of the vehicle rather than providing a beam down the road. Radar sensors or other types of sensors may also be misdirected.

Illuminating the road in front of the vehicle as well as down the road of the vehicle is important for the driver being aware of the curvature of the road ahead and objects in the road, as well as other drivers being aware of the vehicle. One example system is provided in <CIT> which discloses a head lamp system for a straddled motor vehicle. The head lamp system is operable in high beam mode and low beam mode and comprises a head lamp unit positioned centrally in the front cowl of a vehicle and a sub lamp unit including multiple individual sub-lamps mounted in the cowl to the left and right of the head lamp unit which can be operated according to the bank angle.

This section provides a general summary of the invention, and is not a comprehensive disclosure of its full scope or all of its features.

The present invention provides a lighting system for a vehicle such as but not limited to a motorcycle.

In one aspect, the present invention provides a lighting system for a vehicle having a vehicle structure, as defined in claim <NUM>. The lighting system includes a headlight housing, a primary high beam element disposed within the headlight housing for forming a primary high beam light output, a secondary high beam element disposed within the headlight housing for forming a secondary high beam light output, the secondary high beam element being discrete from and vertically aligned with the primary high beam element and comprising a first secondary high beam element and a second secondary high beam element, a lean angle sensor coupled to the vehicle structure for generating a lean angle signal, and a controller coupled to the lean angle sensor for controlling the first secondary high beam element and the second secondary high beam element in response to the lean angle signal.

Optionally, when the lean angle signal corresponds to a lean angle greater than a predetermined angle, the first secondary high beam element is illuminated and the second secondary high beam element is not illuminated.

Optionally, the primary high beam element is illuminated and when the lean angle signal corresponds to a lean angle greater than a predetermined angle, the first secondary high beam element is illuminated and the second secondary high beam element is not illuminated.

Optionally, the light system comprises a plurality of driving lights, wherein the controller controls the driving lights in response to the lean angle signal.

The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present invention.

The drawings described herein are for illustrative purposes only of selected examples and not all possible implementations, and are not intended to limit the scope of the present invention.

Although the following description includes several examples of a motorcycle application, it is understood that the features herein may be applied to any appropriate vehicle, such as snowmobiles, all-terrain vehicles, utility vehicles, moped, scooters, etc. The examples disclosed below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather, the examples are chosen and described so that others skilled in the art may utilize their teachings.

Referring now to <FIG>, a vehicle <NUM> such as a motorcycle is set forth. The motorcycle includes various mounting configurations for vehicle sensors. In <FIG>, a top view of the vehicle is illustrated. The vehicle sensors may be mounted in various locations of the vehicle. The sensors may be incorporated within different types of light housings. This allows designers to maintain an aesthetically pleasing appearance without sensor locations being obvious. The vehicle <NUM> includes a frame <NUM>, handlebars <NUM> and a pair of wheels <NUM>, one of which is illustrated in <FIG>. The front wheel may be enclosed by a fender <NUM> on which a sensor <NUM> is mounted. As mentioned above, the sensor <NUM> may be incorporated within a light housing <NUM> or other decorative trim disposed on the fender <NUM>. The sensor <NUM> may be, but is not limited to, radar, lidar or other proximity sensors.

Sensors <NUM> may be coupled to the steering mechanism <NUM> of the vehicle. The sensors <NUM> may be directed in various directions including toward the side of the vehicle <NUM>. The frame, highway bars and lower fairings are suitable places to mount sensors <NUM>.

The vehicle <NUM> may also include a seat <NUM>. Seat <NUM> may include sensors <NUM> directed at lateral sides of the vehicle <NUM>.

The vehicle <NUM> may also include saddlebags <NUM>. The saddlebags <NUM> may have various sensors incorporated therein. The sensors may include a front-facing sensors <NUM>, rear-facing sensors <NUM> or side-facing sensors <NUM>.

The vehicle <NUM> may also include a headlight assembly <NUM>. The headlight assembly <NUM> may be an adaptive headlight, as will be described in more detail below. In addition, the headlight assembly <NUM> may include a sensor <NUM> such as a visibility sensor.

Referring now specifically to <FIG>, the vehicle <NUM> may include a fork <NUM> used for securing the front wheel <NUM> to the frame. A side-mounted sensor <NUM> may be used for sensing adjacent vehicles. One sensor <NUM> may be used on either side of the wheel <NUM> on each fork <NUM>.

Referring now to <FIG>, a front view of the vehicle <NUM> is illustrated in further detail. In this example, the sensor <NUM> may be enclosed within the headlight <NUM> as illustrated in <FIG>. However, various other locations for a sensor include a sensor <NUM>, <NUM> positioned below the headlight <NUM>. Other sensors <NUM> may be located within the driving lights <NUM>. Sensors <NUM> may be located in the turn signals <NUM>.

Referring now specifically to <FIG>, a portion of the vehicle <NUM> has been cut away. By positioning the sensors such as the sensor <NUM> between a light housing <NUM> and a lens <NUM> of the headlight assembly <NUM>, the controller <NUM> may be located in a remote location. That is, the controller <NUM> may be positioned in a more favorable environment in terms of heat and moisture. In the present example, the controller <NUM> is located within the instrument panel of the vehicle <NUM>. This allows the controller <NUM> which is microprocessor based to operate in more favorable positions. The controller <NUM> may be located within a common housing <NUM> with a sensor <NUM>, which may be an inertial sensor sensing the attitude of the vehicle. The controller <NUM> may be incorporated as part of a vehicle control module (VCM).

Referring now to <FIG>, the headlight assembly <NUM> is illustrated in further detail. In this example, a primary portion <NUM> of low beam elements is set forth. The low beam elements 210A, 210B and 210C form a primary portion or first portion <NUM> of the low beam. In this example, elements 210A and 210C are adaptive, meaning that they are controlled to be on (emitting light) or off (non-light emitting) depending upon the lean angle of the vehicle, as will be further described below. A first secondary portion <NUM> of the low beam may be formed using a plurality of elements 220A, 220B, 220C and 220D. A second secondary portion <NUM> of the low beam may be formed by elements 222A, 222B, 222C and 222D. As is illustrated in this example, four lenses are used to form the first secondary portion <NUM> and the second secondary portion <NUM>. However, various numbers of elements may be used.

The elements 220A-220D and 222A-222D may be disposed at least partially around the periphery of the light housing. The elements 220A-220D and 222A-222D may be generally rectangular in shape and extend radially inward. However, other shapes and sizes may be used. Further, each element or several elements may be differently shaped.

A high beam having a primary portion <NUM> is also illustrated. The primary portion <NUM> may be a single lens as is illustrated in the present example.

A secondary portion <NUM> of the higher beam is also set forth. The secondary portion <NUM> of the high beam may include a first lens 232A and a second lens 232B. The secondary portion <NUM> of the high beam may be adaptive in that one or the other or both of the elements 232A, 232B may be activated or light-emitting depending upon the various conditions of the vehicle such as the lean angle.

Referring now to <FIG>, the light output of the primary low beam elements 210A, 210B and 210C are illustrated. The screen has markings at <NUM> degrees which represents the center in front of the vehicle, L15 which represents <NUM> degrees from the center toward the left and L30 which represents <NUM> degrees to the left of center. Likewise, the screen also has a position marked R15 for <NUM> degrees to the right of center and R30 for <NUM> degrees to the right of center. In this example, lens 210B is shaped to illuminate the area between L15 and R15. Lens 210A is shaped to illuminate the area between L30 and R30. Likewise, lens 210C also illuminates the area between L30 and R30.

Referring now to <FIG>, the screen <NUM> is illustrated in a similar manner. However, the lenses for each of the elements 210A, 210C are changed to direct light in a different direction. That is, element 210A illuminates the area between <NUM> degrees and L30. Element 210B illuminates the area between L15 and R15, as set forth in <FIG> and element 210C illuminates the area between <NUM> degrees and R30. Depending upon the configuration of the vehicle <NUM>, either of the examples set forth in <FIG> may be implemented.

During operation, the elements 210A-210C of the low beam may be selectively activated. In a standard driving mode in which the vehicle is relatively straight, that is, with no lean angle, all of the elements 210A-210C may be used to illuminate the road surface. However, as the vehicle begins to lean in either direction, the individual elements 210A, 210C may be turned off or reduced in intensity to prevent objects that are not in the path of travel from being illuminated. A reduction in intensity may be about <NUM> percent of the "on" intensity. That is, as the vehicle is driven, and the vehicle leans, the elements 210A and 210C may be selectively controlled to "off" or reduced intensity in response to the lean angle of the vehicle. That is, selective control of elements 210A and 210C may be between <NUM> and <NUM> percent.

Referring now to <FIG>, the headlight <NUM> illustrated in <FIG> is set forth at an angle <NUM> corresponding to the lean angle of the vehicle.

Referring now to <FIG>, a simulated view of a landscape including a road <NUM> is illustrated. In this example, the light is generated using the primary low beam light that is illuminating various portions in a manner similar to that set forth above with respect to <FIG>. In this example, however, the element 210C is not illuminated or is reduced to about <NUM> percent of the fully "on" intensity to reduce driver distraction and help the driver focus on the path. Element 210C is illuminating above the travelled direction.

<FIG> is a simulated view similar to <FIG> operating with a single low beam element 210B.

Referring now to <FIG>, a light output plot of the output of the secondary portion <NUM> is set forth. In this example, all of the light from elements 222A-222D is illustrated for comparison purposes. The light output for all elements 220A-220D is the mirror image. In this example, the shape of the lenses corresponding to the elements may be shaped differently in <FIG>. In <FIG>, a high punch output beam is illustrated for each of the elements. Although the elements are not shown, the output of the elements is shown by the reference numerals. When contrasting <FIG> has higher punch and sharp cutoff which shows a greater amount of light directed to the edges of the corresponding element. In <FIG>, the intensity of the light is reduced toward the rightmost edge of each element. Depending on the various types of vehicles and the desired engineering requirements, a suitable shape for the elements 222A-222D to achieve the punch or cutoffs may be selected by a vehicle design. As the vehicle <NUM> leans, the elements 222A-222D may be selectively and sequentially illuminated to provide the desired light output.

Referring now to <FIG>, the output for the adaptive high beams is illustrated. In <FIG>, the screen plot of the light output of the primary element <NUM> illustrated in <FIG> is set forth. In <FIG>, both of the secondary elements 232A and 232B form the elements <NUM> and <NUM> on the screen. As is illustrated, the output of the combination of the primary element <NUM> and the secondary elements 232A, 232B provide high punch and less spread. However, should lower punch and more spread be desirable, the shape of the lenses of the elements 232A and 232B may be changed so that the light output corresponding to the boxes <NUM> and <NUM> are formed by the high beams.

Referring now to <FIG>, the elements 232A and 232B may be selectively used to generate a light output. In this example, the light and thus the lean angle of the vehicle is toward the left. When the vehicle leans toward the left, directing the high beam corresponding to the element 232A is undesirable. In this example, element 232A is shut off and thus only the output of element 232B is provided. That is, <FIG> is translated to the angular position while one of the boxes, corresponding to <NUM>, is shut off or not illuminating.

In <FIG>, an alternate control scheme for high, low beam lights and driving lights is illustrated at various lean angles. The position E corresponds to straight up where the three primary low beam elements are illuminated. Once enough lean angle is detected, the secondary low beams begin to illuminate depending on the direction. Once the lean angle is over a predetermined amount, only the central primary element is illuminated along with more secondary elements. Eventually, in positions A and I, four secondary elements and one primary low beam element are illuminated. The primary low beam elements act the same when high beams are selected. However, once the predetermined angle increases, the secondary high beam element is illuminated in the direction of the lean angle.

Referring now to <FIG>, a simplified version of a headlight <NUM>' is illustrated. The headlight <NUM>' may include the sensor <NUM>' housed therein. The sensor <NUM>' may, for example, be a radar sensor or optical sensor. Of course, the light <NUM>' may include one of more of the elements set forth in <FIG>. The sensor <NUM>' is preferably placed behind the outer lens covering <NUM> so that the radar beam <NUM> is emitted therethrough.

Although a headlight <NUM>' is illustrated, the sensor <NUM>' may be included in various types of light housings such as a brake light, an auxiliary light, a turn signal or the like. A number of different locations of lights or other locations on the vehicle were illustrated in <FIG>.

The headlight <NUM>' may also be an adaptive headlight for changing the length of the beam pattern emitted from the vehicle. As illustrated in <FIG>, the beam pattern illustrated is wider W<NUM> and shorter D<NUM> at lower speeds such as <NUM> kilometers per hour illustrated in <FIG>. In <FIG>, the beam pattern is at a mid-range (length D<NUM> and width W<NUM>) at <NUM> kilometers per hour and the beam pattern is at a far range D<NUM> and narrower width W<NUM> at <NUM> kilometers per hour as illustrated in <FIG>. The distance D1, D2 and D3 may be calculated based upon a time. Therefore, the distance may correspond to a time for seeing ahead <NUM> seconds. Thus, although the distances D1-D3 are different, the amount of length or the time in front of the vehicle that is illuminated may be the same. Thus, based upon a speed, the amount of beam pattern ahead of the vehicle may be calculated.

Referring now to <FIG>, a block diagrammatic view of the control system <NUM> is illustrated. In the example, a controller <NUM> that may correspond to the controller <NUM> illustrated in <FIG> is set forth. In this example, the control system <NUM> may control the operation of a radar housing <NUM> or a light housing <NUM>. That is, the controller <NUM> may control the output of the radar within the radar housing <NUM>. The controller <NUM> may also control the light housing <NUM> by controlling an actuator <NUM> to adjust the focal length of the system by moving the outer lens a small distance to correspond to the desired distance for the amount of illumination to be provided by the light housing. The actuator <NUM> may be a small motor that moves the lens or changes the pressure within a water- or oil-filled membrane. An example of this will be set forth below in <FIG>.

A switch <NUM> may be in communication with the controller <NUM>. The switch <NUM> may be used for selecting between a low beam headlight output or a high beam headlight output.

A speed sensor <NUM> may provide a speed of the vehicle to the controller <NUM>. Various types of speed sensors may be used including conventional rotational sensors coupled to the vehicle wheels.

The controller <NUM> may also be in communication with an inertial measurement unit <NUM>. The inertial measurement unit <NUM> may be one or more sensors used for sensing various types of movement of the vehicle. The inertial measurement unit <NUM> may generate signals for lateral acceleration, longitudinal acceleration and vertical acceleration. The inertial measurement unit <NUM> may also generate signals corresponding to a roll moment, a yaw moment and a pitch moment. The lean angle of the vehicle may be calculated using the yaw moment and roll moment.

A steering wheel angle sensor <NUM> may also be incorporated into the system. The steering wheel angle sensor <NUM> may provide a steering wheel angle corresponding to the angle of the front wheel relative to the frame of the vehicle. Various sensors may be used for controlling the distance the light projects from the vehicle and for controlling the number of primary low beam elements, the number of secondary low beam elements and the number of secondary high beam elements based upon a lean angle of the vehicle.

Referring now to <FIG>, a block diagrammatic view of the controller <NUM> of <FIG> is illustrated in further detail. In this example, various modules within the controller <NUM> determine the various light elements that are illuminated. For example, a lean angle determination module <NUM> determines the lean angle from the inertial measurement unit <NUM>. In particular, the lean angle corresponds generally to the roll angle of the vehicle. However, as described below, a correction based on yaw angle in the yaw correction module <NUM>. Thus, the output of the lean angle determination module <NUM> is a lean angle signal.

A speed module <NUM> generates a speed signal from the output of the speed sensor <NUM>. The speed module may, for example, receive a plurality of pulses from the speed sensor <NUM> and convert the pulses to a vehicle speed.

A pitch angle determination module <NUM> determines a pitch angle from the inertial measurement unit <NUM>. The pitch angle may be used for compensating the direction of the headlights based upon a load. That is, more than just side-to-side movement of the light may be compensated for. If the pitch angle of the vehicle indicates the front end of the vehicle is higher than the rear end of the vehicle, the light may be actuated into a more downward position using the actuator <NUM> illustrated above.

The steering angle module <NUM> generates a steering wheel angle signal from the steering wheel sensor <NUM>. The steering wheel angle may be used to determine the direction of the vehicle to determine the elements desired for illumination.

A light driving control module <NUM> is used to control modes of operation of the adaptive light. In particular, the light driving control module controls the high beam, low beam and switching therebetween. A switch control module <NUM> may receive a switch signal from a switch and provide an output to a low beam control module <NUM> and a high beam control module <NUM>. That is, the switch module <NUM> may generate an indication as to whether a high beam or low beam is desired by the vehicle. In response to the lean angle <NUM> or lean angle corrected by the yaw angle acceleration, the primary elements and secondary elements of the low beam and the high beam may be controlled in the desired manner as described above. A focal point actuator <NUM> may control the focal point of the light housing <NUM> so that a desired focal point and thus the beam pattern of illumination in front of the vehicle may be changed.

Referring now to <FIG>, the light housing <NUM> is illustrated in further detail. The light housing <NUM> may include an actuator controller <NUM> and an actuator <NUM> as mentioned above. The controller <NUM> and actuator <NUM> may be within the housing or external to the housing, as illustrated in <FIG> as <NUM>. The actuator <NUM> may pressurize oil for changing the shape of the lens element or changing the position of the lens element relative to the light emitters. The light emitters may, for example, be LEDs or incandescent lights. The LED light emitters may also be moved while the lens is held stationary. The controller <NUM> and actuator <NUM> may also be connected to the secondary high beam elements <NUM> for controlling one or more of the high beam elements according to the lean angle of the vehicle. The primary low beam elements <NUM> may also be in communication with the actuator <NUM> for illuminating or controlling the illumination of each individual element as described above. The secondary elements <NUM>, <NUM> may also be controlled by the actuator <NUM> based upon the lean angle of the vehicle. A radar element <NUM> may also be controlled by the actuator <NUM>. The separation of housing <NUM> from housing <NUM> of <FIG> allows strategic positioning and incorporation of various components in each.

Referring now <FIG>, the actuator <NUM> illustrated in <FIG> is illustrated coupled to an external lens <NUM> of the vehicle. By moving the lens <NUM> in the direction indicated by the arrows <NUM>, the light output may be changed from a narrow beam <NUM> to a wide beam <NUM> and sizes therebetween. Thus, by shifting the focal point of the exterior lens <NUM>, the actuator <NUM> provides the desired light output for the light assembly. The actuator <NUM> may be an electrical motor, a hydraulic element such as an oil-filled element or a water-filled element which manipulates the exterior surface of the lens.

Referring now to <FIG>, a method for controlling the headlight of a vehicle is set forth. In step <NUM>, the lean angle of the vehicle is continually monitored by the controller so that the appropriate elements of the high beams and low beams are illuminated or extinguished. The lean angle is determined from the inertial measurement unit set forth above. However, a discrete lean angle sensor may also be used.

Step <NUM> determines whether a lean angle is less than a second predetermined angle. If the lean angle is less than a second predetermined angle, step <NUM> operates all the primary low beam elements. The low beam elements may be configured in a manner to provide the light illustrated in <FIG>. By operating while the lean angle is less than a second predetermined angle, the vehicle is more vertical.

Referring back to step <NUM>, if the lean angle is not less than a predetermined angle, the lean angle is compared to various thresholds in steps <NUM>, <NUM> and <NUM>. Therefore, the amount of the secondary low beam elements that are illuminated are changed. On the "low side" of the vehicle, the elements are activated one by one while the elements on the high side of the vehicle may be deactivated. This allows the illumination patterns illustrated in <FIG>. As mentioned above, it is desirable not to have elements too high to dazzle oncoming drivers. Thus, in step <NUM> when the lean angle is greater than a third predetermined lean angle, the appropriate secondary elements are operated. That is, the secondary low beam elements on one side are powered on or illuminated and the elements on the other side are extinguished in step <NUM>.

In step <NUM>, it is determined whether the lean angle is greater than a fourth predetermined angle. The fourth predetermined angle would be less than the third predetermined angle. The third predetermined angle is an indicator that the vehicle is at a substantial lean angle. The fourth predetermined angle is less than the third predetermined angle and it is determined whether the lean angle is greater than the fourth predetermined angle in step <NUM>. If the lean angle is greater than the fourth predetermined angle, step <NUM> illuminates the selected secondary elements and turns off other selected secondary elements on the other side of the vehicle depending on the lean angle. Step <NUM> is performed if the lean angle is not greater than a fourth predetermined angle. In step <NUM>, it is determined whether the lean angle is greater than a fifth predetermined angle. The fifth predetermined angle is less than the fourth predetermined angle. This indicates that even a lower amount of angle but greater than the second predetermined angle of step <NUM> which indicates the vehicle is nearly upright. If the lean angle is greater than the fifth predetermined angle, step <NUM> illuminates selected secondary elements and extinguishes or turns off other secondary elements based upon the lean angle as described above. In steps <NUM> and <NUM>, the primary elements on either side of the middle may be extinguished. That is, the amount of secondary elements that are illuminated is based upon the lean angle. For high lean angles, all four elements as illustrated in <FIG> may be illuminated on the low side of the vehicle. The amount of comparison to different angular thresholds depends upon the number of elements. As the vehicle turns from side to side, the lean angle is used to illuminate or extinguish or turn off various elements. The lights may be gradually turned off to provide more pleasing effect.

When step <NUM> is negative and after steps <NUM>, <NUM>, <NUM> and <NUM>, step <NUM> is performed. In step <NUM>, a switch setting to determine whether the high beams or low beams are desired is monitored. The control set forth herein corresponds to <FIG>. If the high beams are illuminated, step <NUM> is used to determine whether the lean angle is greater than a first predetermined angle. If the angle is not above the predetermined angle, the primary high beam element is operated in step <NUM>. Referring back to step <NUM>, if the lean angle is greater than a predetermined angle, the primary element of the high beam is operated plus one of the secondary elements.

Referring back to step <NUM>, if the switch indicates that low beams are to be operated or the high beams are operated, step <NUM> is performed. That is, in one example, the low beams are operated according to the following for both high beams and low beams. After steps <NUM> and <NUM>, the method ends and may be restarted as the lean angle changes.

Referring now to <FIG>, a method for adjusting the focal point of the light is set forth. In step <NUM>, the vehicle speed is determined. In step <NUM>, a desired visibility distance is established. The desired visibility distance corresponds to an amount of time corresponding to the amount of illumination provided by the headlights. In step <NUM>, the focal position of the headlight is determined based upon the speed. At low speeds, the spread of the light may be greater but the distance does not need to be as great as at high speeds where the light beam is narrower and illuminate a further distance in front of the vehicle. In step <NUM>, an actuator is controlled based upon the calculated focal position of the headlight. As the vehicle speed changes, the method set forth in <FIG> is repeated and the focal length and width of the headlight is changed.

Referring now to <FIG>, a plot of the controlled light output lean angle versus the adaptive light output level is set forth. A deadband <NUM> is provided where the light level does not match the calculated lean angle. Within the deadband <NUM> the controlled light output lean angle is set to zero due to the mismatch. In the shoulder areas 1712A and 1712B, a the controlled light output lean angle ramps the values from zero at the deadband back to a value where the light output lean angle matches the actual lean angle.

Referring now to <FIG> the deadband <NUM> is shown relative to a calculated lean angle. A maximum and minimum threshold relative to a yaw angle acceleration is also illustrated. The yaw angle acceleration drops into a threshold zone and causes the calculated light lean angle to start stepping down until it is within the deadband. As illustrated, as the yaw drops below the threshold, the calculated lean angle starts stepping down at <NUM>. When the calculated lean angle drops below the deadband, the stepping down stops at <NUM>.

Referring now to <FIG>, the improved system illustrates the yaw angle acceleration dropping below a threshold and the calculated lean angle starts to step down. However, when the yaw angle acceleration rises above the threshold, the calculated lean angle stops stepping down. That is, when the yaw angle acceleration drops into the threshold zone and causes the calculated light lean angle to start stepping down. The stepping down stops as soon as the yaw angle acceleration comes back above the maximum threshold.

That is, while the vehicle is traveling straight there should be no yaw angle acceleration. While cornering there will be a measurable yaw angle acceleration that increases proportionally with the factors such as speed, corner radius and the bank angle. A minimum and maximum yaw angle acceleration may be defined such that when the yaw angle acceleration is between the minimum and the maximum yaw angle acceleration it can be assumed that the vehicle is not cornering. In the present example, plus or minus two degrees per second<NUM> is used as the yaw angle acceleration threshold. However, other values may be used. Thus, the threshold may be defined as a maximum absolute value relative to two degrees per square second. The yaw angle acceleration threshold may be used as an indicator of a very low lean angle to compensate for roll angle inaccuracy at low lean angles. When the yaw angle acceleration is between the maximum and the minimum yaw angle acceleration thresholds, the vehicle is most likely not cornering regardless of the roll acceleration calculation. Thus, the roll acceleration calculation may be corrected based upon the bank angle. When the yaw angle acceleration is within a threshold the calculated bank angle can be incrementally decreased until it is within the lighting deadband.

Referring now to <FIG>, a flowchart of a method for correcting the light lean angle is set forth. In step <NUM> the inertial measurement unit measures the various accelerations including the yaw angle acceleration and the roll acceleration. In step <NUM>, the roll acceleration and a previous bank angle are used to calculate a new bank angle. In step <NUM> it is determined whether the yaw angle acceleration is less than a threshold. When the yaw angle acceleration is less than a threshold in step <NUM>, the bank angle is determined and compared to a deadband. When the bank angle is outside of the deadband in step <NUM>, the bank angle is decreased in step <NUM>. When the yaw angle acceleration is not less than the threshold, the bank angle is not outside the deadband and after step <NUM>, step <NUM> uses the bank angle to calculate the light elements to illuminate in step <NUM>.

Referring now to <FIG>, a fault detection circuit <NUM> using components from the adaptive headlight that has an adaptive headlight housing <NUM> and components from the vehicle such as the light driving control module <NUM> and the fault detection module <NUM>. The light driving control module <NUM> is coupled to the adaptive headlight housing <NUM> using a connection <NUM>. In this example, a high beam input 2014A and a low beam input 2014B are set forth. The adaptive headlight housing <NUM> may be coupled to a common or ground such as vehicle ground <NUM>. The adaptive headlight housing <NUM> includes light controlling circuitry <NUM> that is used to drive the light elements <NUM>. Many governmental entities require a vehicle manufacturer to provide an indication when a headlight is faulty. Traditional headlights are very simple and fault detection module within a vehicle includes the capability to detect an open circuit such as when the filament of the bulb is broken. Another failure mode in a typical system is when an excessively high amount of current is drawn through the light assembly. In this case, the fault detection system <NUM> of the vehicle would not adequately notify the vehicle operator of a fault in one or more of the light elements <NUM> particularly when only a few light elements <NUM> (or segments thereof) are faulty. Errors in the circuitry or software would not be detectable using traditional systems.

In the following examples, the light controlling circuit <NUM> may include a fault detection module <NUM> and switching control circuit <NUM>. The switching control circuit <NUM> is used to control switches 2034A and 2034B within the housing <NUM>. In a normal setting, the switches 2034A and 2034B are used to communicate with the connection 2014A and 2014B, respectively. That is, in normal operation the connectors 2014A and 2014B are coupled to the light controlling circuitry <NUM> through the switches 2034A and 2034B, respectively. When a fault is detected in one of the high beam elements, the fault detection module <NUM> generates a high beam fault signal that is communicated to the switching control circuit <NUM>. The switching control circuit <NUM> changes the position of the switch 2034A to place a different circuit component between the connector 2014A and the light control circuitry <NUM>. In this example, a resistive load 2036A is placed within the circuit. The resistive load 2036A has a different electrical characteristic then the normal connection between the electrical connection 2014A and the switching control circuit <NUM>. By providing a change in the electrical characteristics, the fault detection module <NUM> of the vehicle may control a fault indicator <NUM> to indicate to the vehicle operator that a fault is present within the high beam elements. The fault indicator <NUM> may, for example, be an amber indicator light that is illuminated either constantly or flashing, a multi-segment LED generating a code error, a touchscreen display generating an error or circuitry that is used to drive the high beam element to rapidly flash or provide some other change in the characteristic to indicate to the vehicle operator that the high beam is not functioning properly.

The low beam circuitry may also operate in the same manner. The low beam includes a resistive load 2036B that is switched into the circuitry when an error or fault is detected by the fault detection module <NUM>. In the same manner, the fault detection module <NUM> controls the fault indicator <NUM> to inform the vehicle operator that a fault is present in the low beam light elements.

The fault indicator <NUM> may be illuminated when the fault detection module <NUM> within the adaptive headlight housing <NUM> determines a fault. Faults may include, but are not limited to, one or more of the low beam or high beam elements having an open circuit. In an adaptive headlight, various other errors may be detected such as a software error, circuitry malfunction, individual light emitting diodes segment failures, a sensor error (e.g., IMU) and the like.

Referring now to <FIG>, another way to indicate to the fault detection module <NUM> that an error has occurred is by providing an open circuit between the connections 2014A and 2014B and the light control circuitry <NUM>. In this example, a switch 2050A is disposed within the high beam circuit and a switch 2050B is disposed within the low beam circuit within the housing <NUM>. When the fault detection module <NUM> determines a fault within the high beam light elements or the low beam light elements, the appropriate switch 2050A or 2050B are activated into an open position. By providing an open circuit, the fault detection module <NUM> provides an indicator appropriate for a fault within either the high beam or low beam elements. The remainder of the circuit of <FIG> is the same and is appropriately labeled in <FIG>.

Referring now to <FIG>, the circuit illustrated in <FIG> has been modified to include a current draw element 2054A and 2054B that are disposed within the high beam circuit and the low beam circuit, respectively. In this example, a current draw element is switched by the switching control circuitry <NUM> when a fault is indicated. The current draw element 2054A and 2054B may be sized to allow a fault to be indicated to the fault detection module <NUM> without the fault detection module <NUM> shutting down the entire light control circuitry <NUM>. The current draw elements 2054A and 2054B are used to change the electrical characteristics of the circuit within the lighting assembly.

Referring now to <FIG>, step <NUM> illustrates the adaptive headlight functioning in a fully functional manner. In step <NUM> a fault is detected. When no fault is detected step <NUM> is again performed. When a fault is detected in step <NUM>, step <NUM> changes an electrical load on the light input pin/connector to the light driving control module. That is, the electrical characteristic of either the high beam or low beam or general light control connection is changed.

Referring now to <FIG>, the first two steps <NUM> and <NUM> are identical as set forth above. However, in this manner step <NUM> determines whether the high beam or low beam elements are active. When the high beam elements are active, step <NUM> determines whether a change in the electrical load or other electrical characteristics is present within the high beam input. That is, when the electrical characteristic of the connection 2014A is provided, step <NUM> allows a fault to be indicated by the fault indicator <NUM>.

In step <NUM>, when the load beam is active and an electrical load or electrical characteristic of the load beam circuitry is indicated at the connection 2014B, a fault may be indicated at the fault indicator <NUM>.

Referring now to <FIG>, the same elements <NUM>, <NUM>, and <NUM> are provided in this example and will not be repeated. In step <NUM>, when the high beam is determined to have a fault, an open circuit is generated by the circuit illustrated in <FIG>. When a low beam element indicates a fault when the low beam is active in step <NUM>, step <NUM> generates an open circuit and a fault may be indicated by the fault indicator <NUM>.

Referring now to <FIG>, the flowchart of <FIG> is repeated in that steps <NUM>, <NUM> and <NUM> are identical. However, in this manner step <NUM> is performed when the high beams are active in step <NUM> and a fault is detected by the fault detection module <NUM>. The current draw may be increased by switching a current draw element 2054A or 2054B into the circuitry such as in <FIG>. When a low beam element is active in step <NUM> and a fault is detected at the fault detection module <NUM> for the low beam element, step <NUM> increases the current draw in the low beam input and thus the fault is detected at the fault detection circuit <NUM>.

Referring now to <FIG>, a method having the first three elements of <FIG> is set forth. In this example, the description is not repeated. When a high beam is active in step <NUM>, step <NUM> is performed. In step <NUM> the current draw is increased on the high beam connector 2014A above a vehicle control module's threshold to set a fault but below a threshold that the voltage control module turns off the high beam driver within the light driving control module <NUM>. As was illustrated above, an electronically actuated switch that adds a resistive load within the headlight housing <NUM> may be performed. For example, a resistive load 2036A may be provided. Of course, other electrical characteristics may also be changed and sensed.

After step <NUM>, step <NUM> detects an error state using the light driving control module. The light driving control module, may be part of the vehicle control module. A high beam failure is thus indicated by flashing gages such as a round gage to indicate the high beams are not functioning properly. In addition to or instead of step <NUM>, step <NUM> allows the vehicle control module to switch to the low beam light output and thus a high beam may not be provided when a fault is indicated at the high beam elements.

Referring back to step <NUM>, when the low beam is active step <NUM> increases the current draw on the low beam input above a vehicle control module threshold to set a fault. The current draw is below that which would shut down or turn off the low beam driver within the light driving control module <NUM>. This is performed in the same manner as that set forth in step <NUM>, but with the low beams. After step <NUM>, step <NUM> detects the error state at the fault detection module and enters a low beam fault or failure mode. After step <NUM>, step <NUM> may be performed to generate an indicator that the low beams are faulty.

Referring back to step <NUM>, the vehicle control module may also be switched to a high beam input in step <NUM>. That is, the high beams may be used as a failsafe for the low beams. However, the light may be pulsed to provide a reduced amount of light output. That is, pulse with modulation may be used to reduce the amount of light output from the high beams so that a failsafe mode may be provided.

In the manner provided in <FIG> and <FIG>, failure detection of low beam elements and high beam elements of an adaptive headlight are provided without having to provide additional equipment in a vehicle. That is, the existing vehicle fault detection circuitry may be used and the adaptive headlight is used to provide the fault indication. This allows an adaptive headlight to be provided in an after market situation because no modification of the vehicle circuitry is required to be provided. But, fault detection is provided.

Also, the resistive load is placed in parallel to the switch in <FIG>. The resistive load may also be placed in series. What is important is that the electrical characteristic of the high beam or low beam circuitry is changed and that the fault detection circuit within the vehicle can detect the change.

Claim 1:
A lighting system for a vehicle having a vehicle structure, said lighting system comprising:
a headlight housing (<NUM>);
a primary high beam element (<NUM>) disposed within the headlight housing for forming a primary high beam light output;
a secondary high beam element (<NUM>) disposed within the headlight housing for forming a secondary high beam light output, the secondary high beam element being discrete from and vertically aligned with the primary high beam element and comprising a first secondary high beam element (232A) and a second secondary high beam element (232B);
a lean angle sensor (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) coupled to the vehicle structure for generating a lean angle signal; and
a controller (<NUM>) coupled to the lean angle sensor for controlling the first secondary high beam element and the second secondary high beam element in response to the lean angle signal.