Abstract:
A vehicular collision avoidance system comprising a system controller, pulsed laser transmitter, a number of independent ladar sensor units, a cabling infrastructure, internal memory, a scene processor, and a data communications port is presented herein. The described invention is capable of developing a 3-D scene, and object data for targets within the scene, from multiple ladar sensor units coupled to centralized LADAR-based Collision Avoidance System (CAS). Key LADAR elements are embedded within standard headlamp and taillight assemblies. Articulating LADAR sensors cover terrain coming into view around a curve, at the crest of a hill, or at the bottom of a dip. A central laser transmitter may be split into multiple optical outputs and guided through fibers to illuminate portions of the 360° field of view surrounding the vehicle. These fibers may also serve as amplifiers to increase the optical intensity provided by a single master laser.

Description:
REFERENCES TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 14/178,675 filed on Feb. 12, 2014 which is a continuation of application Ser. No. 13/285,800 filed on Oct. 31, 2011 both entitled FLASH LADAR COLLISION AVOIDANCE SYSTEM having a common assignee with the present application, the disclosures of which are incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    1. Field 
         [0003]    The present invention relates to the field of remote sensing of objects using LADAR and the application of LADAR to vehicular collision avoidance. 
         [0004]    2. Related Art 
         [0005]    Many collision avoidance systems have been built which rely on microwave radars, scanning LADARs, and passive thermal and IR sensing. LADAR systems typically require the transmission of a high energy illuminating pulse. Historically, these systems rely on solid state lasers operating in the near infrared with a lasing media of Neodymium-YAG or Erbium doped glass. Many of these systems utilize multiple pulses over a period of time to detect remote objects and improve range accuracy. These systems are often based on a single detector optical receiver. To develop a complete picture of a scene, the laser and optical receiver must be scanned over the field of view, resulting in a shifting positional relationship between objects in motion within the scene. Flash ladar systems overcome this performance shortcoming by detecting the range to all objects in the scene simultaneously upon the event of the flash of the illuminating laser pulse. 
         [0006]    U.S. Pat. No. 4,403,220 awarded to Donovan describes a collision avoidance system based on a scanning microwave radar. U.S. Pat. No. 5,5,29,138 issued to Shaw and Shaw details a vehicle collision avoidance system based on a scanning LADAR or sets of scanning LADARs. U.S. Pat. No. 7,061,372 awarded to Gunderson, et. al. describes a modular collision avoidance sensor which may incorporate any number of sensor technologies, including LADAR, ultrasound, radar, and video or passive infrared sensing. 
         [0007]    The present invention is a collision avoidance system enabled by a plurality of vehicle mounted flash ladar sensors incorporating elements of the flash ladar technology disclosed in Stettner et al, U.S. Pat. Nos. 5,696,577, 6,133,989, 5,629,524, 6,414,746B1, 6,362,482, and U.S. patent application US 2002/0117340 A1, and which provides with a single pulse of light the range to every light reflecting pixel in the field of view of the flash ladar sensor as well as the intensity of the reflected light. 
       SUMMARY OF THE INVENTION 
       [0008]    Many attempts have been made to solve the problem of how to create the true 3-D imaging capability and integrate it with a vehicle which would enable a vehicle based collision avoidance. The instant invention makes use of a number of new and innovative discoveries and combinations of previously known technologies to realize the present embodiments which enable the vehicle operator to benefit from a collision avoidance technology with the capacity to provide nearly 360° target detection and monitoring. When integrated with the vehicle navigation and control systems, both collision avoidance and robotic driving are enabled. This ability to operate the LADAR enabled collision avoidance system is provided by practicing the invention as described herein. 
         [0009]    This invention relies on the performance of a plurality of multiple pixel, infrared laser radar modules for capturing three-dimensional images of objects or scenes within the field of view with a single laser pulse, with high spatial and range resolution (Flash LADAR). The figures and text herein describe the electrical and mechanical innovations required to enable a cost effective LADAR based collision avoidance system which is particularly well adapted to the automotive environment, where low cost, reliability, and robust environmental performance are basic requirements. 
         [0010]    The vehicular collision avoidance system utilizes a pulsed laser transmitter capable of illuminating an entire scene with a single high power flash of light. The vehicular collision avoidance system employs a system controller to trigger a pulse of high intensity light from the pulsed laser transmitter, and counts the time from the start of the transmitter light pulse. The light reflected from the illuminated scene impinges on a plurality of receiving optics and is detected by a number of focal plane array optical detectors housed in independent ladar sensor units. An interconnect system typically comprised of a fiber cable and wire harness connects the individual vehicle mounted ladar sensor units to a central LADAR-enabled collision avoidance system which supports the functions central to the described vehicular collision avoidance system. 
         [0011]    The instant invention provides a nearly 360° coverage for a land or sea based vehicle with coverage above and below the plane of travel. While specifically adapted for ground based vehicles, the technology described may be easily applied to boats, hovercraft, and airborne platforms such as helicopters and airplanes. The collision avoidance system pioneers a number of new technical concepts, including the embedding of key LADAR elements within standard headlamp and taillight assemblies, and articulating LADAR sensors adapted to cover terrain coming into view around a curve, at the crest of a hill, and at the bottom of a dip. In one embodiment, a central laser transmitter is split into multiple optical outputs and guided through fibers to illuminate portions of the 360° field of view surrounding the vehicle. In a further embodiment, these fibers also serve as amplifiers to increase the optical intensity provided by a single master laser. 
         [0012]    Therefore it is an object of this invention to provide a LADAR enabled collision avoidance system which has low initial cost, high availability, nearly 360° field of view coverage, ability to proactively adapt to variations in terrain, and can be easily integrated into existing ground based vehicles, watercraft, and airborne platforms. 
         [0013]    The present invention comprises a vehicular collision avoidance system enabled by a flash ladar with a number of sensors specifically adapted for integration into a moving vehicle. The system described is designed to be manufactured economically, and to be integrated into a vehicle with minimum adaptation of the vehicle. Flash LADAR sensors are detailed which are integrated into a forward looking headlamp assembly which may be actuated on a motorized pivot mount. Side mounted flash ladar sensors are described which are integrated into turn signal indicator light assemblies, and rear view sensors are described which are integrated into taillight assemblies. Additionally, the flash ladar enabled collision avoidance system incorporates a central processing unit which incorporates object recognition software. Based on the objects in the field of view of the ladar sensors, the relative motion of these objects, and the vehicle dynamics, the collision avoidance system central processor produces audible, visible, or tactile warnings to the operator of the vehicle. In some cases posing extreme risk, the collision avoidance system takes active control of the vehicle in order to conduct evasive maneuvers. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is an overhead view of an automobile incorporating multiple flash ladar sensors and their overlapping fields of view. 
           [0015]      FIG. 2  is a side view of three possible mounting points for the forward looking flash ladar sensors. 
           [0016]      FIG. 3  is a side view of an automobile travelling along the crest of a hill and in the bottom of a dip in the road. 
           [0017]      FIG. 4  is an overhead view of an automobile travelling along a section of a left-curving roadway. 
           [0018]      FIG. 5  is a diagram of an integrated headlamp and flash ladar sensor. 
           [0019]      FIG. 6  is a diagram of an integrated headlamp and flash ladar sensor which illustrates an alternative arrangement of lensing elements for both illuminating the roadway with visible light and pulsed laser light, and collecting and directing reflected laser light to a detecting focal plane array, and shows washer and wiper hardware for keeping the forward surfaces clean. 
           [0020]      FIG. 7A  is a diagram of an integrated headlamp and flash ladar sensor which illustrates a rectangular arrangement of lighting elements as well as a reflecting lens apparatus for receiving laser light reflected from the scene, and features a laser external to the assembly. 
           [0021]      FIG. 7B  is a diagram of an integrated ladar sensor and headlamp which features a longer focal length reflecting lens and a remote external laser, with pulsed laser light delivered via an optical fiber. 
           [0022]      FIG. 8  is a diagram showing pivot mechanisms attachment to the integrated headlamp and ladar sensor for facilitating two axis angle adjustment. 
           [0023]      FIG. 9  is an overhead view of an alternative to  FIG. 1  showing overlapping fields of view of a ground vehicle employing the ladar sensor of  FIGS. 5 ,  6 ,  7 , and  8 , in which the collision avoidance system employs between four and six sensors, each at a corner of the vehicle. 
           [0024]      FIG. 10  is a block diagram of a collision avoidance system employing a plurality of independent flash ladar sensors. 
           [0025]      FIG. 11  is a detailed system block diagram of an advanced adaptation of the collision avoidance system of  FIG. 10 , which incorporates a number of digital and analog signal processing modules and a low power master pulsed laser transmitter with a distributed fiber amplifier and associated pump lasers. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0026]    A preferred embodiment of the present invention, the Flash LADAR collision avoidance system (CAS), is depicted in block diagram form in  FIGS. 10 and 11 . These FIG.s will be discussed in detail once foundational concepts of the LADAR enabled CAS are explained through the discussion of  FIGS. 1-9 .  FIG. 1  is an overhead diagram which shows one pattern of ladar sensor coverage which will enable a collision avoidance digital signal processor to determine which objects in the path of the vehicle, or travelling on an intercept path, necessitate evasive maneuvers by the host vehicle. 
         [0027]    The host vehicle  6  may be an automobile, boat, ship, hovercraft, airplane or robotic crawler.  FIG. 1  illustrates several basic requirements for a vehicle mounted collision avoidance system. First, a field of view  1  in the direction of travel of the vehicle must extend furthest from the vehicle. The field of view may be rectangular as shown for field of view  1 , to project illuminating laser flashes directly in the path of the vehicle at long ranges while driving on a straight highway  7  at high speed, or in an arc, typically with shorter range and wider field of view  2  to detect nearby objects when maneuvering at low speeds, e.g.; parking. 
         [0028]    Lateral sensor field of view patterns  3  and  4  monitor left and right sides of the vehicle respectively, and operate at medium ranges, providing input over a wide arc to facilitate low speed maneuvering, and to provide some level of early warning capability for potentially higher speed lateral impact events. A rear facing sensor field of view pattern  5  provides sensor coverage in a similar fashion to the side impact sensors  3  and  4 , by detecting stationary or slow moving objects near the rear of the vehicle in a wide arc, thus facilitating low speed maneuvers such as parking, while simultaneously enabling a rear impact sensor with a view of any vehicles approaching from the rear in an uncontrolled manner at higher speeds. 
         [0029]      FIG. 2  details one of the important design considerations regarding the ladar enabled collision avoidance system. A major issue is the question of where to mount the transmitter or transmitters on the vehicle as well as where the optical detectors should be mounted. In most of the previous work by the present inventors, these transmitters and receivers have been co-located as close as possible with parallel and overlapping fields of view along the same radial axis. By mounting the ladar sensor high on the vehicle, it might be possible to sweep an entire 360° field of view, thus keeping one aspect of system complexity to a minimum. However, as the diagram shows, a high mounted ladar sensor  8  co-located with the rear view mirror or dome light position, blind spots arise in the near field below the projection line  12  of the forward field of view  11  of the high mounted ladar sensor  8 . In a similar fashion, these blind spots will appear at the rear of the vehicle below a line of sight from the rear view mirror or dome light position  8  to where this line of sight is cut off by the trunk lid. To a lesser extent, additional blind spots will arise on the left and right side of the vehicle in the near field below a line of sight from the rear view mirror to the bottom of the driver&#39;s side window where it connects with the door panel, and likewise on the passenger&#39;s side where the window connects with the door panel. Other blind spots arise for a high mounted ladar sensor which are caused by the roof supports at either end of the front windshield, the front and rear doors, and the rear windshield. These are commonly referred to in industry parlance as the A, B, and C pillars, respectively. Additional optical transmission blockages may be caused by the vehicle occupants, seatbacks, headrests, and tissue boxes, stuffed animals, etc., stored on the rear windshield deck. The issues of optical transmission blockages are very similar for a high mounted ladar sensor  8  co-located with either the rear view mirror or the dome light. 
         [0030]    As shown in  FIG. 2 , the distance to where the lower line of sight limit  13  intersects the roadway surface  15  is greater in a dash mounted ladar sensor variant  9  than in the high mounted case shown by line  12 . This increase in the blind spots of the dash mounted variant  9  will be further exacerbated in the rear view and sides because of the much lower initial height of the dash mounted sensor  9 , creating a much lower angle as in the angle shown between line of sight  13  and roadway  15 . Additionally, optical transmission blockages in the passenger compartment such as occupants, seats, headrests, etc. will be exacerbated due to their being directly in the viewing path of a dash mounted ladar sensor  9 . These blindspots reduce the ability of the ladar sensor to perform adequately in slow maneuvers such as backing up from a driveway or parking. Though the high mount  8  ladar sensor position is preferable to the dash mount variant  9 , both options have significant limitations. At the bottom of  FIG. 2 , the preferred low level headlamp  18  mounting point or taillight/indicator light level mounting point  10  of the ladar sensor is depicted with a lower line of sight  14 . This mounting arrangement substantially reduces the blindspots in the search pattern identified above with respect to both the high mounted dome light or rear view mirror position  8 , and the mid-level dash mounted variant  9 . High mount  8  and mid-level mounting positions  9  for the ladar sensor would preclude the projection of a near field illumination and search pattern  16  if not mounted at the periphery of the vehicle. Near field illumination pattern  16  can be formed from the same light beam which produces far field illumination pattern  11  using a combination of refractive and diffractive optics. These refractive and diffractive optics may also serve as the collection mechanism for the light reflected from object in the field of view of the ladar sensor. Diffractive optics work on the principle of interference, not bending (refraction) of light. Diffractive optics, which are very thin and compact, are used to shape the laser beam so photons aren&#39;t emitted out to the field of view of the receive optics. 
         [0031]    Returning to  FIG. 1 , the coverage pattern in the horizontal plane could be achieved with four independent sensors. Patterns  1  and  2  can be formed from the same ladar sensor using a combination of refractive and diffractive optics for both the transmission of the illuminating light pulses and the collection of the light reflected from objects in the field of view. Patterns  3 ,  4 , and  5  can be produced from an additional three independent sensors placed at strategic points on the vehicle for a total of four independent sensors. However, in an automobile design, the difficulty associated with finding four new points for mounting of ladar sensors should not be underestimated. Engineers tasked with designing an automobile chassis and body would need to accommodate the additional four openings in the body panels and provide electrical wiring harness interfaces and routing of the harness to the new points. There becomes the need to increase the number of parts used in the sub assemblies and the top assembly, and there would need to be additional stations on the assembly line to install each of the new independent ladar sensors. 
         [0032]    A more sophisticated approach is to reuse the packaging of the headlamps, turn signals, and taillight/brakelight assemblies for the mounting of the ladar sensors. The advantages of this approach build on a significant body of knowledge gained over many years in the automotive industry. Headlamps and taillights have migrated to the periphery of the vehicle for issues of operation and visibility. Long gone are the days of single headlamps mounted at the forward center of the vehicle like a locomotive. Likewise, most headlamps and taillight/brakelight assemblies are mounted at the corners of the vehicle for reasons of illumination of the area of operation of the vehicle, and for visibility of the vehicle to operators of other vehicles in the vicinity. This great body of knowledge should be built on, rather than lightly disregarded when integrating a new function, the ladar sensor, into a moving vehicle such as an automobile. We expect a much easier path to adoption of this new functionality if it can be integrated with the present functions and hardware associated with the pathway illuminating systems of the vehicle rather than a fully independent approach with major accommodations made to the body and chassis and assembly lines if the ladar sensors are not incorporated into the existing pathway illuminating hardware. Therefore, the integrated headlamp and ladar sensor is developed herein as well as the integrated auxiliary lamp and ladar sensor assembly. By auxiliary lamp we mean any short range illuminating lamp or indicator light, to include at minimum, turn signals, brake lights, taillights, parking lights, or any similar lights commonly installed on moving vehicles. 
         [0033]    This approach to integrating the ladar sensor into the headlamp assemblies and auxiliary lamp or indicator light assemblies will produce fields of view as shown in  FIG. 9 , with identical overlapping far field illumination and viewing patterns  11  projected along roadway  7 . The overlapping horizontal projections of near field patterns  16  in  FIG. 9  are from ladar sensors integrated into indicator lights  10  as shown in  FIG. 2 , or from integrated ladar sensor and headlamp assemblies  18  as discussed in  FIGS. 3 and 4 . 
         [0034]    Referring to  FIG. 3 , an important feature of the integrated headlamp and ladar sensor we describe is the ability to steer the field of view of the ladar illumination pulse  11  along with the headlamps mechanically in the vertical and horizontal axes. The diagram in  FIG. 3  shows a moving vehicle  6  travelling at the crest of a hill  87 , with articulating ladar sensor and headlamp  18  at a depressed angle, illuminating the trough at the bottom of the curvature of the hill  87 . Likewise, the bottom of  FIG. 3  shows a moving vehicle  6  travelling at the bottom of a dip in the road, prior to ascending a hill,  17 . In this view, the ladar sensor and headlamp assembly  18  is at an elevated angle, sweeping out the incline of the curvature of the hill,  17  rising in front of it. 
         [0035]      FIG. 4  further illustrates the advantages of the beam steering capability of the ladar sensor and headlamp assembly  18 . Pictured is a motor vehicle  6  approaching a bend to the left in the roadway  19 . Both headlamp and ladar sensor far field beam patterns  11  are steered to the left to sweep out the area in the path of the vehicle at the greatest distance from the vehicle, therefore giving the greatest possible amount of time for collision threat detection and avoidance. 
         [0036]      FIG. 5  illustrates a number of design and construction features of the integrated ladar sensor and headlamp assembly  18 . At the right of  FIG. 5  is shown a cross section showing details of the assembly taken along line SS. The assembly is contained within a glass or high impact plastic transparent envelope  20 . A double lens system for collecting and focusing the light returned from the scene in the field of view is formed by large diameter lens  21  at the front of the assembly, which works with a second lens  35  directly in front of receive sensor  28 . Receive sensor  28  is comprised of an infrared focal plane array mounted atop a readout integrated circuit and thermal management interface. The ladar sensor is comprised of laser light source  31 , receive sensor  28 , and additional electronics contained in electronics housing  29 . Mounted between second lens  35  and receive sensor  28  is an optical bandpass filter  41  which blocks all wavelengths of light except the wavelength of the light from the laser light source  31 , typically 1.57 microns in the preferred embodiment. The laser light source  31  may be a solid-state laser, semiconductor laser, fiber laser, or an array of semiconductor lasers. In the preferred embodiment, laser light source  31  is a disc shaped solid state laser of erbium doped phosphate glass pumped by 976 nanometer semiconductor laser light. In an alternative embodiment, laser light source  31  is an array of vertical cavity surface emitting lasers (VCSELs). The operation of receive sensor  28  will be discussed in greater detail in connection with  FIG. 10 , the system block diagram. Supporting the large diameter lens  21  are a number of lens supports  22  which may be thermosonically bonded to transparent envelope  20 , or formed/molded into transparent envelope  20 . Large diameter lens  21  may be of a material which has a different index of refraction at the transmission wavelength of 1.57 microns from the index of refraction it exhibits at the headlamp illumination wavelengths in the 0.45-0.65 micron range. This dichroic behavior of the material of large diameter lens  21  may be put to good use, creating different illumination patterns for the 1.57 micron ladar sensor illuminating laser  31 , and the visible white light emitting diodes  33 . Visible white LEDs  33  supplant the incandescent or halogen bulbs of traditional headlamps in the instant invention, due to their much higher efficiency, and therefore lower heat production. Shown on the left side of  FIG. 5  is a radial arrangement of eight LED subassemblies ( 33 ,  25 , and  26 ) for simplicity and clarity of the drawing, but the actual number of LED subassemblies is typically much greater, on the order of 32-128, depending on the power desired for the particular headlamp or indicator lamp application. An example of a benefit of a dichroic material for large diameter lens  21  is the ability to project an illuminating 1.57 micron laser pulse in a far field pattern  11  to match the far field pattern of the LED light sources  33 , while at the same time illuminating the near field of the vehicle  6  with 1.57 micron pulsed laser light in a near field pattern  16 , with little or no light from the LED light sources  33  being diverted into the near field. Because the near field of the vehicle is not directly visible from the driver&#39;s position, it makes sense to not divert optical flux from the LED visible light into the near field  16 . It is preferred to have as much of the visible light transmitted so as to illuminate the driver&#39;s line of sight in the far field. 
         [0037]    As noted above, LED light sources  33  are chosen for this application because of their high efficiency. The high efficiency of LED light sources produces real benefits to the integrated ladar sensor and headlamp in three significant ways. First, it reduces heating of the adjacent receive sensor  28  of the ladar sensor. The detector array of receive sensor  28  is typically a two dimensional array of Avalanche PhotoDiodes (APDs), which are sensitive to shifts in operating temperature, and must be operated at a fixed temperature in the preferred embodiment of the invention. In order to keep the temperature of the receive sensor  28  comprised of APD array and readout IC constant, thermoelectric coolers are used as a heat pump to remove excess heat to an associated heatsink at the rear of the electronics housing  29 . Closed circuit control is then used to monitor and maintain the receive sensor  28  at a constant temperature by supplying a variable current to the thermoelectric coolers. Second, the ladar sensor may draw 30-40 watts of power from the vehicle electrical power systems. This additional power requirement can be offset by reducing the electrical power required to illuminate the roadway by substituting LEDs  33  for the traditional halogen or incandescent light sources, thus easing the burdens on the vehicle electrical system design, and facilitating the seamless integration of ladar sensing technology. Third, the dramatically increased life expectancy of the LED light sources reduces the probability the integrated ladar sensor and headlamp assembly  18  will have to be repaired during the life of the vehicle. Because the integrated ladar sensor and headlamp assembly  18  will of necessity be a subsystem with a higher value, the decision to repair or replace the integrated ladar sensor and headlamp  18 , should be based on the higher value component, the ladar sensor. This repair/replace decision is facilitated if the light sources chosen have an extremely low failure rate and very long lifetime as do the LED light sources  33 . 
         [0038]    Each LED light source  33  typically has a molded aspherical lens  25  and reflector/director  26  to collect and project substantially all of the light emanating from LED light source  33  into the far field pattern  11 . Additionally, an optional intermediate lens  23  may be positioned between the molded lens  25  and the large diameter lens  21  to provide additional conditioning of the visible light beam emanating from the LED light source  33 . Intermediate lens  23  may be held in place by support features  24  molded into, formed in, or thermosonically welded to transparent envelope  20 . The intermediate lens  23  may be made of a polymer, or a glass with flexibility and formed in a split ring, with split  36  designed to allow the ring to be compressed in diameter prior to inserting into transparent envelope  20 . Once the intermediate lens  23  with split ring design is compressed, it may be engaged with the detent in support feature  24 , and then released, allowing it to spring out to its full diameter, thereby retained and supported within transparent envelope  20  by support features  24 . Visible LEDs  33  are mechanically supported and electrically connected via printed wiring board  27  which may be a printed circuit board made of fiberglass, alumina, aluminum nitride, or other insulator/conductor printed wiring system. 
         [0039]    To complete the functionality of the integrated ladar sensor and headlamp  18 , a laser light source is necessary and is shown located on a parallel axis with receive sensor  28 . The laser light source has an eye safe filter  32  which limits the wavelength of light emitted through diffuser  34  to only those inherently eye-safe wavelengths of light. Diffuser  34  may be an ordinary refracting lens, an array of diffraction gratings, a series of ground or molded prisms, or a holographic diffuser. In the preferred embodiment, the wavelength of choice is in the range of 1.54-1.57 microns, though many other wavelengths may be useful as a source of illuminating laser light. A zero time reference is established by retro-reflector post  39  attached to transparent envelope  20  which indicates the leading edge of an outgoing laser pulse by feeding back a portion of the outgoing laser pulse energy to the receive sensor  28 , which detects it and processes the pulse in the same manner as all succeeding reflections from the scene in the field of view of integrated ladar sensor and headlamp assembly  18 . This reflected zero time reference optical signal is referred to locally as an Automatic Range Correction (ARC) signal, and the several pixels on receive sensor  28  illuminated by the ARC signal are referred to as ARC pixels, and are the zero time references for all range measurements made by integrated ladar sensor and headlamp assembly  18 . Retro-reflector post  39  may be formed of a plastic or glass and may be integrally molded with transparent envelope  20  or bonded to transparent envelope  20  thermosonically. The preferred method is to have retro reflector post  39  integrally molded into transparent envelope  20  and to apply a white epoxy paint or metallic coating as a reflective coating  40  to the exterior of transparent envelope  20  in line with retro-reflector post  39 . A metallic reflective coating  40  may be applied by any number of methods, including flame spraying, electroplating, or physical vapor deposition. Metallic coating may also be a thin film of metal applied under heat and pressure which causes the base material of transparent envelope  20  to reflow and permanently capture a metallic strip functioning as a metallic reflective coating  40 . The metal chosen for a metallic retro-reflective coating or layer  40  should be impervious to the effects of corrosion as it is an outside, exposed surface. Materials such as stainless steel, nickel, gold, and platinum are appropriate for this function. Finally, a sealant, or passivation layer may be applied over a metallic reflective coating  40  to further reduce the potential effects of a corrosive environment by using any of the above mentioned processes. The preferred method is to use physical vapor deposition in which a target of glass is heated in a crucible within a vacuum chamber to deposit a thin layer of passivating glass over the corrosion resistant metallic reflective coating  40 . Alternatively, if the transparent envelope  20  is plastic, any number of epoxy resins or plastic overmoldings may be applied as a passivating layer over reflective coating  40 . 
         [0040]    Forming the retro-reflecting post  40  within the transparent envelope  20  serves a dual purpose with respect to the ARC signal and ARC pixels. It is expected there will be some non-negligible and undesirable retroreflections from an outgoing laser illuminating pulse from laser light source  31  when the light pulse encounters scratches, dirt, dead bugs, ice, snow, or other light reflecting obstructions which may be adhered to the front surface of transparent envelope  20 . It is important to have the ability to “gate out”, or ignore, these signals by having an ARC signal which occurs later in time than these undesirable retro-reflections from the exterior surface of transparent envelope  20 . The additional delay occasioned by the height of retro-reflector post  39  and its non-unity index of refraction, creates additional delay over the thin sections of transparent envelope  20 , thus making the retro-reflected optical signal from a white or metallic reflective coating  40  occur slightly later in time than the undesired retroreflections from any materials adhered to the exterior surface of transparent envelope  20 . At the far right of  FIG. 5  is the interface connector  30  which carries bidirectional electrical signals, power, ground, and any necessary optical signals to and from the integrated ladar sensor and headlamp  18  and provides connections to the vehicle electrical and optical systems. Resident within electronics housing  29  are a serial communications port for bidirectional communications with a central ladar system controller ( 71  in  FIG. 10 ), power conditioning electronics, and interface electronics including analog to digital converters for reporting the status of the integrated ladar sensor and headlamp  18 , and its associated analog parameters such as temperature, voltage, power consumption, etc. The serial communications port also sends ordered pairs of range and intensity detected by the ladar sensor to the central ladar system controller ( 71  in  FIG. 10 ) and receives commands therefrom to control the direction of the sensor, the intensity of the laser illuminating pulse and the intensity of the LED light sources  33 . Electronics housing  29  also contains circuitry to convert digital signals and commands received from a central ladar system controller to analog values as required to point the integrated ladar sensor and headlamp  18 , to brighten or dim LED light sources  33 , or to run wiper/washer operations described in association with  FIG. 6 . 
         [0041]    Shown at the left of  FIG. 5  is a view looking into the integrated ladar sensor and headlamp  18  along the optical axis OA, showing a number of details of the design including the preferred rectangular shape  38  of receive sensor detector  28  as well as the rectangular shape  37  of the laser light source  31  of the preferred embodiment.  FIG. 5  is not a scale drawing; rather it is intended to illustrate the various design concepts incorporated in the preferred embodiment. Other lensing options with multiple convex surfaces, with concave surfaces, and alternatively, with some prismatic or diffractive surfaces may be employed to achieve the desired effects described herein. A shorter range, wider field of view integrated ladar sensor and auxiliary lamp  10  as anticipated in  FIGS. 2 and 4 , is an adaptation of the design described in association with  FIG. 5 . The integrated ladar sensor and auxiliary lamp  10  uses a wide field of view lens with a short focal length such as a fisheye lens, or an array of diffractive gratings or prismatic elements to survey a field of view in excess of 90 degrees, and up to approximately 180 degrees. The term auxiliary lamp includes taillights, brake lights, parking lights, turn signal indicator lights, fog lights, etc., commonly found on the exterior of an automobile. 
         [0042]      FIG. 6  shows a number of optional features and alternative embodiments of integrated ladar sensor and headlamp assembly  18 . The right half of  FIG. 6  shows a cutaway view of integrated ladar sensor and headlamp  18  along section line DD. As noted with respect to the discussion of  FIG. 5  above, there is a distinct possibility of non-negligible retro-reflections from a variety of materials which could be adhered to the exterior of transparent envelope  20 . A wiper system comprised of electric motor  42 , rotating shaft  43 , and wiper blade  44  works together with washer fluid pumping tube  45  and washer fluid spray nozzle  46  to keep the exterior surface of integrated ladar sensor and headlamp assembly  18  free of bugs, dirt, snow, hail, etc. as much as possible in order to facilitate better 3-dimensional ladar sensor capability. Washer fluid pumping tube  45  has a hose fitting  47  extending towards the rear to engage with a hose from the vehicle windshield fluid reservoir and pump. A different optical design and layout are shown, with a greater number of visible LED subassemblies arranged in a radial pattern. Each LED subassembly in this case features a concave lens  25  together with a parabolic reflector of different shape for a different far field lighting effect. Circuit board support  48  is attached to transparent envelope  20  and creates a mounting point for the LED circuit board  27  assembly which is in a slightly more forward location in this embodiment of the design. 
         [0043]    Connected to circuit board support  48  is lens mount  49  which is shown with two large diameter plano-convex lenses  21  and  50  mounted back to back to provide for a wide field of view for receive sensor  28 , though a number of other lensing arrangements are anticipated, including convex, concave, and aspherical shapes as well as arrays of prismatic and diffractive surfaces. Electrical connections  51  carry power and ground, brightness control, and other bidirectional signals through circuit board support  48  and electronics housing  29  to interface connector  30  for connection to the vehicle electrical systems. A further benefit of using a washer fluid spray system is the location of washer fluid spray nozzle  46 , which is positioned ideally to create a retro-reflected ARC signal suitable for illumination of the ARC pixels of receive sensor  28 . To function reliably in this manner, washer fluid spray nozzle  46  should be made of a corrosion resistant metal alloy such as stainless steel, nickel, gold, or platinum, or be powder coated white. The location of washer fluid spray nozzle  46  well outside the exterior surface of transparent envelope  20 , means the retro-reflected optical signals therefrom will be well delayed past any retro-reflected optical signals caused by bugs, mud, dirt, snow, or ice adhered to the exterior surfaces of transparent envelope  20 , making for an excellent solution to the question of where to locate and how to provide for an appropriate retro-reflected ARC signal suitable for illuminating the ARC pixels of receive sensor  28 . 
         [0044]    A common design trade-off for a ladar sensor is the range versus transmitted power consideration. Greater transmitted power yields additional range, at the expense of more complex laser designs, greater electrical power requirements, and therefore cost and weight of the system.  FIG. 7A  addresses this range problem in a new and unique manner with respect to ladar sensor design. Instead of arbitrarily increasing power to yield range enhancement, a much larger optical gain is realized in the ladar sensor optical receiver of this alternative embodiment by increasing the effective aperture of the ladar sensor optical receiver through beneficial use of a parabolic reflector  53  instead of the traditional glass or polymer lens elements of  FIG. 5 . Moreover, the aspect ratio of the optical aperture created by reflecting mirror  53  may be adjusted to be rectangular  52 , circular, square, or any other desired geometry.  FIG. 7A  illustrates a number of features not found in  FIGS. 5 and 6 . At the left of  FIG. 7A  is a front view of the integrated ladar sensor and headlamp assembly  18 . At the right of  FIG. 7 , a section of the front view along line FF looking to the left is shown. The parabolic reflector  53  captures light passing through the transparent envelope  20  and converges the captured incoming light at focus element  61  which is shown here as a secondary converging mirror, but may be a diverging mirror, or a convex or concave refracting lens, or a lens with an aspherical geometry. Focus element  61  conditions the light to pass through mirror aperture  60  so as to fall on the active area of receive sensor  28 . Focus element  61  is positioned and held in place by support beam  54  which is permanently affixed to, or integrally molded into, parabolic reflecting mirror  53 . Reflecting mirror  53  has a parabolic profile in the preferred embodiment and may be molded or formed out of metal, glass, or a fiber reinforced polymer, or another material suited to a particular application. Reflecting mirror  53  may alternatively be created in a characteristic shape which is spherical, hyperbolic, exponential, or another geometry which suits a particular application. The refractive lens designs as in  FIGS. 5 and 6  do not scale easily to large apertures and higher optical gains. A circular headlamp assembly may typically be 7 inches in diameter, thus leaving 6 inches for a large diameter lens  21  of  FIGS. 5 ,  6 . Such a large diameter lens  21  manufactured out of a solid glass blank will be expensive and heavy, and require a more substantial mechanical mounting system, with the additional associated weight and cost. Because the parabolic reflector  53  may be cast, molded, or formed out of a thin walled glass, powder metal, or fiber reinforced polymer, it will be much lighter for a given aperture and optical gain than an equivalent solid glass lens. This resultant lower weight has many benefits for man-portable and flight systems, and has a much lower cost of fabrication. 
         [0045]    The laser illuminating source  31  in the design embodiment of  FIG. 7A  is positioned outside the transparent envelope  20  of the integrated ladar sensor and headlamp  18 , and is coupled through a fiber coupler  59  and flexible optical fiber  58  and rigid lightguide  57  to corner cube  55 . Corner cube  55  rotates the transmission axis of the illuminating laser light 90 degrees into alignment with the optical axis shown as dashed line OA of the integrated ladar sensor and headlamp assembly  18 . Corner cube  55  may be a high quality device made of ground glass coated with a reflecting mirror surface and mounted to support beam  54  using epoxy, adhesive or mechanical means such as C-clips, U-clips or other friction or compression fasteners, or assembled to diffuser  56  and then attached as a compound unit to support beam  54  using any of the aforementioned attachment methods. Corner cube  55  may alternatively be integrally formed with support beam  54  and coated with a reflective metallic surface, with diffuser  56  attached thereto. Diffuser  56  acts to distribute the illuminating laser light in any of the desired patterns discussed herein, and may be an arrayed waveguide grating, interference filter, holographic diffuser, or other diffractive optic construction. Diffuser  56  may be bonded to corner cube  55  by any number of methods including glass bonding, epoxy or adhesive bonding, or mechanical mounting using sheet metal C-clips, U-clips, or other compression and friction fasteners. Shown at the left of  FIG. 7A  is the rectangular aspect of secondary lens  23  which is optionally included in the various embodiments shown herein. Also visible is the rectangular aspect of mirror aperture  60 , though other shapes are anticipated depending on particular applications of the invention as described herein. 
         [0046]      FIG. 7B  illustrates a number of refinements to the integrated ladar sensor and headlamp assembly  18  incorporating a reflecting mirror  53 . At the left of  FIG. 7B  is a front view of the integrated ladar sensor and headlamp assembly  18 . At the right of  FIG. 7B , a section of the front view along line FF looking to the left is shown. First, support beam  54  has been angled so focus element  61  can be above, or in this case, in advance of reflecting mirror  53 , thus increasing the focal length of reflecting mirror  53 , which is desirable in some cases to allow for an increased optical aperture without penalizing the optical performance. Increase of the optical aperture is desirable to produce a positive effect on optical gain. In this drawing it can be seen the proximity of diffuser  56 , corner cube  55 , and focus element  61  to the interior surface of transparent envelope  20  allows for them to be bonded directly to the transparent envelope  20  and for support beam  54  to be eliminated in low cost applications. An automobile might have two of this type of integrated ladar sensor and headlamp assembly  18 , plus four wide field of view ladar sensors integrated with auxiliary lighting assemblies  18 , resulting in the need for up to six laser light illuminating sources  31 . A further cost reduction mechanism anticipated is the concentration of all six laser illuminating sources into one central laser unit with a six-way power split output. This system architecture will be discussed in association with  FIG. 11 . Shown in  FIG. 7B  is flexible optical fiber  58  connecting within transparent envelope  20  through to interface connector  30  which in this embodiment connects to the vehicle optical and electrical harness (not shown in this FIG.). The optical transmission lines within the optical and electrical wiring harness then connect to a central illuminating laser source which will be discussed in association with  FIG. 11 . 
         [0047]      FIG. 8  illustrates details of the mechanism which provides the ability to point the integrated ladar sensor and headlamp assembly  18  both left and right, and up and down and responds to electrical positioning signals received over sub-assembly wiring harness  65 . Attached to transparent envelope  20  are two motorized horizontal pivots  62  positioned at the top and bottom of transparent envelope  20  which can rotate transparent envelope  20  both left (counter-clockwise) and right (clockwise) around vertical axis line VA. The second horizontal pivot  62  at the bottom of  FIG. 8  may be motorized, or may be a passive pivot consisting primarily of a rotary bearing. Motorized horizontal pivot  62  has electrical connections  66  which provide power, ground, and motor control to the motorized horizontal pivot  62 , and return motor status and rotational position status signals from the motorized horizontal pivot  62 . An outer housing  68  provides an attachment point for motorized horizontal pivots  62 , and may be in the shape of a full shell adapted to the contours of transparent envelope  20 , with adequate clearance to allow for a full range of horizontal and vertical angular displacement of transparent envelope  20 . Outer housing  68  is typically a full shell when the integrated ladar sensor and headlamp  18  is mounted on external hard points such as might be found on a military or utility vehicle. Alternatively, if the integrated ladar sensor and headlamp  18  is housed in a recessed opening in the body of a vehicle, as is typical in an automotive application, the full shell design for outer housing  68  can be replaced with a very simple open yoke which has a flattened toroid shape and only has sufficient depth to provide attachment to both motorized horizontal pivots  62  and motorized vertical pivots  63 . Horizontal pivots  62  and vertical pivots  63  and their respective rotational axes typically lie in the same plane. Motorized vertical pivots  63  attach to outer housing  68  and act to point the subassembly consisting of the outer housing  68 , motorized horizontal pivots  62 , and transparent envelope  20  up or down depending on electrical control signals received over electrical connections  67 . The second vertical pivot at the left of  FIG. 8  need not be motorized, and may be a simple passive pivot with rotary bearing. Electrical connections  67  provide power ground, and motor control signals to motorized vertical pivots  63 , and return motor status and angular position to a central controller. Both sets of electrical signal wires  66  and  67  pass through a vehicle mount  64  which may be a recess in a body panel in an automotive application, or a mounting bracket on an exterior surface of a utility or military vehicle. These two independent sets of electrical connections  66  and  67  then merge in a sub-assembly wiring harness  65  before terminating in an electrical connector  69  which is adapted to connect to the vehicle electrical systems. 
         [0048]      FIG. 9  shows an overhead view of an automobile  6  equipped with two of the integrated ladar sensor and headlamp assemblies  18  described in the text and in  FIGS. 5-8  above. The automobile is also equipped with short range integrated ladar and auxiliary lamp assemblies  10  at the four corners of the vehicle. The long range integrated ladar sensor and headlamp assemblies  18  provide a narrow and long distance field of view  11  along the length of straight roadway  7 , while the short range integrated ladar sensor and auxiliary lamp assemblies  10  provide an overlapping and much wider and shorter range field of view  16 . Typically the shorter range integrated ladar sensor and auxiliary lamp assemblies  10  are not capable of traversing, but operate in a staring mode, to reduce complexity and costs associated with the auxiliary lighting functions. In staring mode short range sensors are not capable of traversing in either a lateral angle or vertical angle like the headlamp assemblies. The overlapping region  70  between short range fields of view  16  at the rear of the vehicle is an area where object identification can be enhanced by post processing and comparing the 3-D images from the left and right short range integrated ladar and auxiliary light assemblies  10 . Object identification can be enhanced by the object rotating or moving through the field of view, or by the motion of the observing platform, or by simultaneous capture of 3-D information from two or more surfaces on the object not directly viewable from the same point of view, necessitating two independent ladar sensors with fields of view converging on the object in question as in overlapping region  70 . 
         [0049]      FIG. 10  shows a simplified system block diagram of a typical installation on a vehicle as anticipated herein and described in the preceding  FIGS. 1-9 . A ladar based collision avoidance system consisting of a central ladar system controller  71  connects to six independent ladar sensors through bidirectional connections  72  and  73 . Two long range units, each comprising an integrated ladar sensor and headlamp  18 , connect to system controller  71  through a set of bidirectional electrical and optical connections  72 . Connections  72  are comprised of electrical wires, optical fibers, and hybrid electrical/optical connectors in the preferred embodiment. Four short range units, each comprising an integrated ladar sensor and auxiliary lamp  10  connect to the system controller  71  through a set of bidirectional optical/electrical connections  73 . Connections  73  are comprised of electrical wires, optical fibers, and hybrid electrical/optical connectors in the preferred embodiment. Each integrated ladar sensor and headlamp  18  and integrated ladar sensor and auxiliary light  10  have at their core a receive sensor  28  first referenced herein in connection with the discussion of  FIG. 5 . Receive sensor  28  is comprised of a two-dimensional focal plane array of avalanche photodetectors mounted atop a readout integrated circuit in the preferred embodiment. A square array of 128×128 avalanche photodetectors on an indium phosphide substrate comprises the focal plane array of the preferred embodiment. The focal plane array is bonded to and electrically connected to a readout integrated circuit via a square array of 128×128 indium bumps formed on the circuit side of the focal plane array. Each detector of the array is individually connected to a unit cell of the readout integrated circuit. The unit cell contains an input low noise amplifier, bandpass filter, threshold detecting circuit, analog sampler, and analog sample shift register, as well as a timing circuit referenced to a global input indicating the start of a laser illuminating pulse. Other signal conditioning circuitry resides on the readout integrated circuit which enable high fidelity reception and detection of low level optical signals reflected from objects and features in the field of view of the ladar sensor. Additional support circuitry resides on printed circuit boards within electronics housing  29  of  FIG. 5  which provide global timing references, buffer the readout integrated circuit outputs, convert analog signals to digital signals, convert digital signals to analog signals, provide necessary bias voltages, and set or adjust variables used within receive sensor  28 . Each ladar sensor of the preferred embodiment is of the flash ladar type. As used herein, a flash ladar is capable of illuminating a field of view with a single pulse of laser light, detecting the reflections from the field of view incident upon a two-dimensional array of light sensitive pixels, and measuring both the intensity and range to each feature in the field of view identifiable by an optical return incident upon a pixel in the two-dimensional array. Further details of the operation of receive sensor  28  are given in the citations of the present inventors previous work in the prior art references which are incorporated herein by reference 
         [0050]      FIG. 11  details the inner workings of ladar system controller  71  and amplifies on the nature of its interoperation with a variety of external integrated ladar sensor and vehicle headlamp and signal lamp modules. Ladar system controller  71  is comprised of seven basic elements, each connected and operating as follows in this preferred embodiment. A digital processor/controller  81  supervises the operations of the ladar system controller internal components, as well as controlling communications with the host vehicle through bidirectional connections  85 . Processor/controller  81  is a general purpose microcomputer integrated circuit in the preferred embodiment, but may be a specialized automotive processor adapted specifically to a vehicle manufacturer requirement, or a state machine such as a field programmable gate array or other programmable logic device. If the processor/controller  81  is a state machine type of device, non-volatile memory  80  is not required and can be eliminated. Typically, upon power-up of the ladar system controller  71 , processor/controller  81  initiates a boot-up sequence wherein the non-volatile memory  80  is accessed for the operating firmware which is loaded into a memory resident within processor/controller  81 . The memory resident within processor/controller  81  is typically volatile memory such as DRAM. Non-volatile memory  80  may also be resident on some processor/controller  81  integrated circuit designs in the form of ROM or PROM. If sufficient non-volatile memory is available within processor/controller  81 , external non-volatile memory  80  may be eliminated to reduce cost and simplify design. Normally, non-volatile memory  80  is comprised of ROM, PROM, Flash memory, or optical or magnetic storage media. 
         [0051]    Processor/controller  81  supervises the data communications port  82 , which is a general purpose Ethernet port in the preferred embodiment. Data communications port  82  may also be of a type specifically adapted to the vehicle market such as a CAN bus interface port, IDB-1394, SAE J1708 interface, or any of a multiplicity of other choices. Data communications port  82  may also be resident on processor/controller  81 , and is often included on many commercially available general purpose and automotive digital controller integrated circuit designs. The host vehicle  6  may also provide through bidirectional connections  85  and data communications port  82  periodic updates to the firmware resident on the non-volatile memory  80 , which would typically occur during scheduled maintenance visits or vehicle recalls. The host vehicle may also provide through data communications port  82  a number of important data to the ladar system controller  71  during normal operation, such as current time and date, vehicle position, speed, acceleration, turning rate, angle of incline/decline, weather data, or other vehicle or global data useful in managing and controlling the vehicle ladar sensors and headlamps and auxiliary lamps. 
         [0052]    Processor/controller  81  determines the timing and initiates the pulsing of illuminating pulsed laser transmitter  79  in the embodiment detailed in  FIG. 11 . The pulsed laser transmitter  79  is a low power or medium power semiconductor laser in this alternative embodiment, with output in the 1.54-1.57 micron wavelength. The optical output of pulsed laser transmitter  79  is passed through a length of erbium doped optical fiber which is simultaneously optically pumped by a number of semiconductor laser diodes at a nominal wavelength of 976 nanometers, though other wavelengths of pump light may be used. The amplifier/pump diodes module  78 , comprised of a coil of erbium doped fiber and several pump laser diodes create an amplified and intensified optical illuminating pulse with sufficient power to illuminate all of the required fields of view ( 1 , 2 , 3 , 4 , 5 , 11  or  16 ) of the various and several ladar sensors positioned on the vehicle  6 . Pulsed laser transmitter  79  and amplifier/pump diodes  78  are typically housed together in laser transmitter module  86 , but other arrangements are anticipated. The output of laser transmitter module  86  is then split into six output fibers  76  by optical power divider  77 . Optical power divider  77  typically splits the optical signal from laser transmitter  79  into six fiber outputs  76  with unequal power ratios. Optical power divider  77  may be an optical fiber coupler, or may be comprised of a series of neutral density filters, or may be a spatial optical power divider using a lens to condition the optical propagating mode appropriately to be divided amongst a number of optical outputs. Two high power laser light signals are provided for use by long range units LRU 1  and LRU 2 , which are typically of the type of integrated ladar sensor and headlamp  18  described in  FIGS. 5-8 . Four lower power laser light signals are provided for use by short range units SRU 1 -SRU 4 , which are typically of the type of integrated ladar sensor and auxiliary lamp  10  described in  FIGS. 5-8 . The six fiber outputs  76  are connected to the remote ladar sensor units SRU 1 -SRU 4  and LRU 1  and LRU 2  through a fiber cable and wire harness  74  which may be routed throughout the vehicle in parallel with the host vehicle  6  wiring harness. 
         [0053]    Connections to each long range integrated ladar sensor and headlamp unit  18  at the terminus of the fiber cable and wire harness  74  are made through bidirectional connections  72  as described with respect to  FIG. 10 . Connections to each short range integrated ladar sensor and auxiliary lamp unit  10  at the terminus of fiber cable and wire harness  74  are made through bidirectional connections  73  as described with respect to  FIG. 10 . In an alternative to the embodiment of laser transmitter  86  described above, the coil of erbium-doped fiber is removed from amplifier/pump diode module  78 , and a length of erbium doped fiber is connected between output fibers  76  and each ladar sensor unit  10  or  18  positioned on the vehicle  6  periphery. The fiber cable and wire harness  74  is in this alternative embodiment an active optical system, with six separate optically amplifying erbium doped fibers routed through the harness  74 . Fiber cable and wire harness  74  may be partially comprised of steel or metallic wire, Kevlar®, or other fiber strength members. Fiber cable and wire harness  74  is typically also comprised of conductive wires of copper, aluminum, German silver, or other electrically conductive material. Fiber cable and wire harness  74  also comprises a number of optical waveguides suitable for optical communications or transfer of high power optical pulses, and fabricated from any number of glass or polymer compounds characterized for these purposes. Finally, the individual strength members and electrical conductors and optical waveguides of fiber cable and wire harness  74  are typically bound together by tape wound around the bundle, plastic tubing slipped over the bundle, or a plastic jacket overmolded onto the outside of the bundle. 
         [0054]    Processor/controller  81  also connects to sensor interface  84  which serves to condition the digital signals from processor/controller  81  appropriately for transmission to any one of two long range sensor units  18  or four short range sensor units  10 . Sensor Interface  84  has six bidirectional connection ports  75  which carry signals to ladar sensor units  10  and  18 , and return signals therefrom. These six bidirectional connection ports  75  connect with electrical conductors and optical waveguides embedded within fiber cable and wire harness  74 . The bidirectional connection ports  75  may be parallel electrical bus, serial electrical interface, serial or parallel optical interface, or some combination of electrical and optical interfaces, and also provide electrical power and ground return signals in the preferred embodiment. Sensor interface  84  also receives status signals and data signals from each of the long range sensor units  18  and short range sensor units  10  through connections  72  and  73 , fiber cable and wire harness  74 , and bidirectional connection ports  75 . The data signals consist of range and intensity pairs for each pixel in a two-dimensional focal plane array, which provide a complete 3-D image of an object or scene in the field of view of the sensor, from a single point of view. Sensor interface  84  passes status data to processor controller  81  and object and scene data in the form of ordered range and intensity pairs to scene processor  83 . Sensor interface  84  may contain analog to digital converters, digital to analog converters, pulse width modulation circuits, or any of a variety of other interface type circuits useful for controlling and monitoring a remote peripheral ladar and lighting subsystem. Sensor interface  84  may be an integrated circuit, and in some cases, may be resident on processor/controller  81 . 
         [0055]    Scene processor  83  makes use of the data received from all six ladar sensors of the short range type  10  and long range type  18  to synthesize a composite view of the area in front of, behind, and surrounding the vehicle  6  and objects within these fields of view ( 1 , 2 , 3 , 4 , 5 , 11 , and  16 ). Scene processor  83  also identifies and tracks objects both static and moving within the composited scene and features in the scene posing a risk, and may also compute the relative risk and timing of a potential impact with any of these objects or features in the composited scene. Alternatively, scene processor  83  may be resident outside of ladar system controller  71  and be associated with the host vehicle  6  central computing function, in which case ordered pairs of scene data are merely passed from sensor interface  84  directly to data communications port  82  and thence to the host vehicle  6  for further processing. It is also envisioned ladar system controller  71  may be entirely encompassed within the vehicle  6  central electronics and computing function, and may even be largely realized as a software/firmware function executable on the vehicle  6  standard computing platform. Several modes of operation for the overall collision avoidance function are envisioned. A first mode, enabled by the several described embodiments, consists of simply displaying a 3-D graphics image showing the various details of stationary features in the scene and objects in motion which may be in the path of the vehicle  6  or on a collision course with the host vehicle  6 . This first described mode relies on the vehicle  6  operator to make judgements and apply vehicle controls appropriately to maneuver the vehicle  6 . This first described mode is fully supported by the specification herein minus the details of the display. A second mode, in which warnings of an impending collision are communicated to the vehicle operator, relies on a collision threat computation made by scene processor  83  or by the host vehicle  6  systems based on the 3-D range and intensity data provided by the various embodiments described herein. In this second mode, the specification of the Flash LADAR Collision Avoidance System as described herein may require the host vehicle to make computations of risk based on the 3-D data provided, and warn the vehicle  6  operator by visual, tactile, or auditory means. In a third operational mode, host vehicle  6  makes computations of risk or threat of collision based on 3-D data provided by the invention described herein, and applies control to vehicle  6  steering, braking, and engine systems to effect collision avoidance and/or steer and guide the vehicle autonomously. All three of the described collision avoidance modes are supported and enhanced by the presence and operation of the Flash LADAR Collision Avoidance System comprised of the various embodiments described herein in association with the numbered drawings. 
         [0056]    Although the invention of the Flash LADAR Collision Avoidance System and the integrated ladar sensor and headlamp/auxiliary lamp and associated systems have been specified in terms of preferred and alternative embodiments, it is intended the invention shall be described by the following claims and their equivalents. 
         [0057]    Having now described various embodiments of the disclosure in detail as required by the patent statutes, those skilled in the art will recognize modifications and substitutions to the specific embodiments disclosed herein. Such modifications are within the scope and intent of the present disclosure as defined in the following claims.