Abstract:
An augmented-reality helmet comprises a full-face motorcycle helmet with a look-down micro-display that projects a virtual image in-line with the helmet&#39;s chin bar. In order to accommodate the power requirements, the helmet includes a battery pack mounted at the base of the motorcyclist&#39;s skull. A wind turbine charges the batteries. Exhaust from the turbine is then deducted through the helmet to cool the battery pack and/or the motorcyclist&#39;s head. The turbine is controllable so that it can operate as a circulating fan to provide ventilation. A digital gyroscope provides a control input to a controller for operating a steerable headlight of the motorcycle to track the rider&#39;s head movements; and provides acceleration output to an algorithm that will contact emergency responders if the rider is non-responsive after a collision. A 170 degree rear-view camera is mounted within an aerodynamic fairing on the back of the helmet.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    This invention relates generally to display systems for helmets and in particular for display systems for motorcycle helmets. 
         [0002]    Heads-up displays have been suggested for implementation in a multitude of transportation applications including automobiles, aircraft and motorcycles. Heads-up displays typically comprise an image projector, an optical collimator; and a beam splitter (combiner). The beam splitter is typically an angled flat piece of transparent or partially reflective material located directly in front of the viewer. The beam splitter reflects the image from the image projector in such a way that the user is able to see the field of view and the projected image at the same time. The optical collimator focuses the image from the image projector into parallel rays of light so that the user sees a virtual image that appears to be at an infinite distance. 
         [0003]    The necessity of having a beam splitter as part of a heads-up display causes little inconvenience in automobiles and aircraft where there is a significant amount of space between the user and the front windscreen of the vehicle within which to mount the beam splitter. For motorcycles, however, installing a beam splitter in the limited space between the rider&#39;s face and the helmet windscreen presents significant design obstacles. U.S. Pat. No. 5,537,092 issued to Suzuki et al. suggests simplifying the information displayed to a motorcycle rider (e.g. by using a linear array of LEDs) and projecting it as a virtual image along the base of the visor (partially obstructing the field of view) as a means of overcoming the space limitations inherent in helmet information displays. This approach, however, severely limits the amount of information that can be communicated to the motorcycle rider and results in a reduction of the rider&#39;s field of view. 
         [0004]    Additionally, as the demand for more and more real-time display of information increases, the processor speed and power consumption necessary to accommodate the demands also increases. In a wireless environment, this dictates the need for larger and heavier batteries in the helmet battery pack, use of tethered batteries and/or powering the helmet with a cable from the vehicle power system. US patent application 2009/0109292 to Ennis for example discloses a video camera system including a heads-up display that is operated from a battery belt pack connected to the camera by a cable. This is not an ideal implementation for a motorcycle helmet since a cable connected between the motorcyclist&#39;s helmet and a belt-mounted battery would be cumbersome especially with the exposed cable subjected to windblast at high speeds. 
       SUMMARY OF THE INVENTION 
       [0005]    The present invention comprises a helmet having a battery-operated augmented reality display. According to an illustrative embodiment, the helmet comprises a full-face motorcycle helmet with a look-down micro-display that projects a virtual image in-line with the helmet&#39;s chin bar (which is space that is already obstructed from the motorcyclist&#39;s field of view.) In order to accommodate the power requirements of the micro-display and associated processor, a battery pack consisting of 4 lithium ion batteries each rated at 2200 mAh for a total capacity of 8800 mAh housed within a crescent-shaped housing that is attached to the rear of helmet at the base of the motorcyclist&#39;s skull. This unique battery mounting position puts the center of mass of the helmet as close as possible to the base of the neck so that, despite the mass of the batteries, the helmet provides little inertial resistance to quick movements of the head. In the illustrative embodiment, the helmet includes a wind turbine that operates to charge the batteries when the helmet is exposed to a wind blast of greater than approximately 10 mph. Exhaust from the turbine is then deducted through the helmet to cool the battery pack and/or the motorcyclist&#39;s head. The turbine is controllable so that at low speeds and high ambient temperatures the turbine operates as a circulating fan to provide ventilation to cool the motorcyclist&#39;s head. The helmet further includes a three axis digital gyroscope mounted to the helmet controller board which (1) provides a control input to a controller for operating a steerable headlight of the motorcycle to track the rider&#39;s head movements; and (2) in the event of a rapid deceleration possibly indicating an accident, provides acceleration output to an algorithm that will contact emergency responders if the rider is non-responsive. In the illustrative embodiment, the helmet further comprises a 170 degree rear-view camera mounted within an aerodynamic fairing on the back of the helmet. The rear-view camera eliminates blind spots behind the rider&#39;s head while the aerodynamic fairing reduces lift and reduces wind buffeting noise of the helmet. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0006]    The present invention will be better understood from a reading of the following detailed description, taken in conjunction with the accompanying drawing figures in which like references designate like elements and, in which: 
           [0007]      FIG. 1  is a front perspective view of a helmet incorporating features of the present inventions; 
           [0008]      FIG. 2  is a diagrammatic cross section of the helmet of  FIG. 1 ; 
           [0009]      FIG. 3  is an exploded view of a mounting system for the display of the helmet of  FIG. 1 ; 
           [0010]      FIG. 4  is a representative view from the perspective of a user wearing the helmet of  FIG. 1 ; 
           [0011]      FIG. 5  is a functional block diagram of the electronic modules of the helmet of  FIG. 1 ; 
           [0012]      FIG. 6  is a cross section of the helmet of  FIG. 1 ; 
           [0013]      FIG. 7  is a partial cross section of a portion of  FIG. 6  showing details of the rearward-facing camera; 
           [0014]      FIG. 8  is a partial cross section showing details of the forward-facing camera; 
           [0015]      FIG. 9  is a perspective view of the helmet of  FIG. 1  with the battery pack removed; and 
           [0016]      FIG. 10  is an enlarged view of a portion of  FIG. 6  showing details of the air-powered generator. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    The drawing figures are intended to illustrate the general manner of construction and are not necessarily to scale. In the detailed description and in the drawing figures, specific illustrative examples are shown and herein described in detail. It should be understood, however, that the drawing figures and detailed description are not intended to limit the invention to the particular form disclosed, but are merely illustrative and intended to teach one of ordinary skill how to make and/or use the invention claimed herein and for setting forth the best mode for carrying out the invention. 
         [0018]    With reference to the drawing figures and in particular  FIG. 1  there is shown a helmet  10  incorporating features of the present invention. Although helmet  10  is depicted as a motorcycle helmet, a helmet incorporating features of the present invention may be implemented as a bicycle helmet, industrial safety helmet, military or other helmet without departing from the scope of the invention. Helmet  10  is preferably constructed of conventional materials with an inner liner formed of expanded polystyrene or polypropylene foam (EPS) and an outer shell  12  made from a homogeneous plastic such as polyamide, polyethylene or polycarbonate, or from a composite material such as fiberglass, aramid, carbon fiber or other composites. 
         [0019]    Helmet  10  includes a conventional face shield  14  and a chin bar  16 . Chin bar  16  has a plurality of conventional ventilation intakes  18  which are adjustable to allow a controlled amount of air to enter the helmet for the purpose of reducing fogging of face shield  14  in humid weather and/or for ventilation of the rider. Helmet  10  further includes a plurality of air intakes  20  and a forward-facing camera port  24  the function of which will be discussed more fully hereinafter. 
         [0020]    With reference to  FIGS. 2 and 3 , helmet  10  includes a display device  24  mounted to the rear surface  26  of chin bar  16 . Display device  24  preferably comprises a virtual image display (VID) unit consisting of a liquid crystal display (LCD), backlight, collimating optics and magnification optics encased in a single device. In the illustrative embodiment, the VID unit comprises a 0.59″ WVGA CyberDisplay® display unit manufactured by Kopin Corporation of Westboro, Mass. Display device  24  is attached to chin bar  16  by means of a hinge unit  28 , attached to a track engaging member  30 . Track engaging member  30  engages a horizontal track  32  having a substantially T-shaped cross section which is rigidly attached to rear surface  26  of chin bar  16 . 
         [0021]    With additional reference to  FIG. 4 , track engaging member  30  and tack  32  form a sliding mount that enables display device  24  to be moved from the right side position  24 A to the left side position  24 B of chin bar  16  to accommodate left eye dominant and right eye dominant users. Track engaging member  30  is locked in place along track  32  using a thumb-wheel cam  34  or similar locking mechanism. The tilt angle of display device  24  may be adjusted by moving the lower surface  36  outward as necessary and locking the display device  24  in place using thumbscrew  38  acting on curved bracket  40 . Track engaging member  30 , track  32  and cam  34  are preferably made of injection-molded plastic such as polyamide, polyethylene or polycarbonate. Hinge unit  28  may be a conventional strap hinge but is preferably a “live” hinge made of homopolymer polypropylene or other suitable plastic material. As shown in  FIG. 2 , Display device  24  produces a virtual image  44  which appears to the rider to be behind the chin bar  16  at optical infinity. Because the virtual image  44  appears to be behind (i.e. passing through) the chin bar  16 , the virtual image  44  appears in an area that is already obscured from the rider&#39;s field of view and therefore does not interfere with or reduce the rider&#39;s field of view as with prior art helmets. Optionally the virtual image  44  can be positioned at the top edge of the chin guard. 
         [0022]    With additional reference to  FIG. 5 , helmet  10  includes a helmet control module  50  mounted within the interior of outer shell  12 . Helmet Control Module (HCM)  50  comprises a System on Chip (SoC) integrated circuit  52  for managing the video and audio I/O, Wi-Fi connection, power management and other functions. HCM  50  may also include a digital output gyroscope/accelerometer  54  the purpose of which is discussed more fully hereinafter. HCM  50  receives video information via a Wi-Fi link  62  which HCM  50  then converts into the appropriate video format for display on display device  24 . Although in the illustrative embodiment HCM  50  receives information via Wi-Fi link  62  the invention is not limited to Wi-Fi wireless link. Other wireless communication protocols such as Bluetooth® or other wireless protocols now existing or hereafter developed may be used within the scope of the invention. HCM  50  similarly processes audio information received via Wi-Fi link  62  which is then amplified and played through headset  56  housed within helmet  10 . HCM  50  similarly processes voice commands, which may be received via microphone  58  embedded in or otherwise attached to helmet  10 . In the illustrative embodiment, System on Chip IC  52  comprises a Broadcomm BCM 2835, Wi-Fi link  62  comprises a Texas Instruments CC3000, the display driver comprises an Intersil TW8835 and the audio amplifier comprises a Maxim MAX98090. 
         [0023]    As noted hereinbefore, HCM  50  includes a gyroscope/accelerometer  54  the purpose of which is twofold. Gyroscope/accelerometer  54  may be used to track the head movements of the rider in order to operate a main or auxiliary headlamp that moves in sync with the rider&#39;s head rather than with the front wheel. Additionally, however, gyroscope/accelerometer  54  may be used to provide input to an algorithm that automatically contacts emergency responders in the event of a sudden deceleration (indicative of a possible collision) followed by an absence of movement and/or absence of vocal command. To avoid false positive detection of a collision, an additional sensor such as a proximity sensor and/or thermal sensor is incorporated to determine if the helmet is being worn, or has simply been removed and thrown onto the ground or otherwise discarded. In the illustrative embodiment, gyroscope/accelerometer  54  comprises a Maxim MAX21000 3-D rate sensor. 
         [0024]    With additional reference to  FIGS. 6-8 , helmet  10  is equipped with a rear facing camera  60 , preferably having a 150°-200°, preferably approximately 170° field of view. As is known in the art, it is common to equip motorcycle helmets with the rear spoilers in order to reduce lift and/or wind buffeting of the helmet and associated noise at high speed. In the illustrative embodiment, rear-facing camera  60  is mounted within rear spoiler  64  of outer shell  12  thereby utilizing what would otherwise be wasted space. The image from rear-facing camera  60  is processed by HCM  50  and displayed on VID  24  thereby providing the rider with a rear view image, obviating the necessity of the rider to turn his/her head in order to view oncoming traffic. Optionally, rear facing camera  60  may be gyroscopically stabilized using the output from gyroscope/accelerometer  54 . An additional chin spoiler  100 , preferably formed of a soft polymer material may be attached to chin guard  16  to further reduce wind noise and lift at high speeds. Optionally, chin spoiler  100  may include a microphone and/or additional electronics for operating VID  24  and is removably attached with magnets (e.g. with neodymium or other rare earth permanent magnets) which also act as signal transmitters between chin spoiler  100  and helmet  10 ). 
         [0025]    Macroscopic adjustments of rear-facing camera  60  may be affected by moving lens port  66  upwards and downwards within corresponding apertures  68  and  70  formed in the outer shell  12 . Movement of lens port  66  enables rear-facing camera  60  to pivot about a pivot  72 . Appropriate seals  74  disposed between lens port  66  and apertures  68 ,  70  are provided for weatherproofing. Helmet  10  may optionally be equipped with a forward-facing camera  76 . The mounting and adjustment of forward-facing camera  76  is identical to the mounting and adjustment of rear-facing camera  60  and therefore will not be discussed in detail herein. Coaxial infrared light emitting diodes  78  are also included to improve visibility in low-light conditions. In the illustrative embodiment rear-facing camera  60  and optional forward-facing camera  76  each comprises an OV7670 Robot Camera Module manufactured by Shenzhen Shanhai Technology Ltd. of Guangdong, China. Additional sensors, such as scanning LIDAR and radar are used to extend the rider&#39;s visual range during night or impaired weather conditions. These sensors are also used to detect objects under all atmospheric conditions so as to warn the rider of a possible impact. The warning may consist of an image displayed on VID  24 , a visual warning symbol, as well as an audio signal. The rider will have the option to add full or partial automatic brake control to assist in impact prevention. 
         [0026]    The power requirements of HCM  50  and the other components embedded in helmet  10  necessitates use of a relatively high-capacity battery pack to provide reasonable service life between charges. With additional reference to  FIG. 9 , in order to minimize the adverse effects of mounting a heavy, high-capacity battery pack, helmet  10  incorporates a battery pack  80  comprising a body having a substantially arcuate profile within inside radius R 1  of approximately 65 millimeters and an outside radius R 2  of approximately 92 millimeters and a height H of approximately 75 millimeters. The shape of battery pack  80  allows it to fit low and close around the base of the rider&#39;s neck extending substantially from ear-to-ear, while the outer surface conforms to the helmet outline. By positioning battery pack  80  low and close around the base of the rider&#39;s neck, the moment of inertia of battery pack  80  is minimized relative to the normal turning and tilting motion of the rider&#39;s head. Battery pack  80  is replaceable using conventional plug-in connectors and releasable catches. Optionally, helmet  10  includes a barrier wall formed as part of outer shell  12  to isolate battery pack  80  from the rider wearing helmet  10 . 
         [0027]    With reference to  FIGS. 6 and 10 , helmet  10  is equipped with an internal air passageway  82  which leads from air intake  20  to exhaust port  84 . Ram-air entering air intake  20  passes through an air-powered electrical generator such as air turbine/generator assembly  86  housed within air passageway  82 . Electricity generated by air turbine/generator assembly  86  is used to augment the power supplied by battery pack  80 , thereby extending battery life. A portion of the ram-air passing through the air turbine/generator assembly  86  may also be directed to a series of cooling ports  88  to cool the rider&#39;s head in warm weather. The remaining portion of the ram-air passing through the air turbine/generator assembly  86  exits exhaust port  84  which is connected to air inlet  90  of battery pack  80 . Air entering air inlet  90  is directed through a series of cooling channels  92  formed in battery pack  80  to cool the batteries within battery pack  80  ultimately exiting battery pack  80  via battery pack exhaust port  92 . In warm weather and slow speeds, air turbine/generator assembly  86  can be electrically reversed to operate as a circulating fan to cool the rider&#39;s head by drawing air through air intake  20  and discharging it through cooling ports  88 . A thermal sensor may be incorporated into the helmet to determine when the fan should be switched on to cool the helmet interior. 
         [0028]    With reference again to  FIG. 5 , a main control module (MCM)  100  is a System on Chip integrated circuit provided to control certain functions associated with helmet  10 . MCM  100  includes a smart phone link  102  (iOS, Android or other smart phone operating system) to provide GPS navigation, voice and data communication and other functions associated with a smart phone  104 . MCM  100  also includes the input output control  106  receiving signals from the manual control interface  108 . In the illustrative embodiment, although most commands are contemplated to be voice commands via microphone  58 , a manual control interface such as a joy-button or other physically manipulated switch array may be provided as appropriate. MCM  100  further includes a light sensor control  110  which receives signal from an ambient light sensor  112 . Light sensor control  110  adjusts the light output of VID  24 , determines when infrared LEDs  78  are necessary and performs other functions as necessary based on the ambient light conditions. Light sensor control  110  may also be used to adjust the darkness of face shield  14  to control the ambient light within the helmet. Alternatively face shield  24  itself may have an auto-dark function. MCM  100  also includes a wireless or wired interface with the vehicle engine management system to receive vehicle speed, engine oil pressure, engine temperature, fuel reserve, fuel economy and other vehicle metrics. In the illustrative embodiment, the System on Chip IC comprises a Broadcomm BCM 2835, the smart phone link comprises a USB to iOS (iPhone) cable and the ambient light sensor comprises a Maxim MAX44009 light sensor. 
         [0029]    Although certain illustrative embodiments and methods have been disclosed herein, it will be apparent from the foregoing disclosure to those skilled in the art that variations and modifications of such embodiments and methods may be made without departing from the invention. For example, although in the illustrative embodiment display device  24  is not a heads-up-display, use of a heads-up display in combination with the other features of the present invention is considered within the scope of the invention. Additionally, although voice commands and/or manual switches are shown in the illustrative embodiment, simple thought commands (e.g. yes/no) detected by EEG are within the scope of the invention as are blink detection commands using an optical eye or eyelid detector. Additional programming functionality may include lockouts that prevent manual input under certain conditions, e.g. speed above a particular threshold, so as to avoid an unsafe condition. Accordingly, it is intended that the invention should be limited only to the extent required by the appended claims and the rules and principles of applicable law. Additionally, as used herein, references to direction such as “up” or “down” are intend to be exemplary and are not considered as limiting the invention and, unless otherwise specifically defined, the terms “generally,” “substantially,” or “approximately” when used with mathematical concepts or measurements mean within ±10 degrees of angle or within 10 percent of the measurement, whichever is greater.