Abstract:
An Outrigger Obstruction Detection System for an Aerial Fire Truck that will warn the driver of an impending obstruction to an outrigger prior to full extension of the outrigger. The system comprises ultrasonic sensors located at or near each outrigger assembly on the aerial fire truck, which can be programmed to detect an object within the travel range of the outrigger. In addition, a control/indicator panel is mounted in the cab of the aerial fire truck. The control/indicator panel is positioned in the cab to allow the driver physical and visual access. The control/indicator panel contains the power switch, diagram of the truck and indicator lights used to warn the driver of an obstruction. The sensors provide an electrical signal to a control/indicator panel located in the cab of the aerial fire truck to alert the driver if an object is detected. This alert allows the driver to reposition the truck to clear the obstruction, which in turn reduces the time to react to the emergency. The ultrasonic sensors are affixed to the aerial fire truck via a pivotal mounting assembly, which allows proper sensing alignment to be achieved.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This application claims priority on U.S. Provisional Application Ser. No. 60/766,777, filed Feb. 10, 2006, entitled Outrigger Obstruction Detection System for Aerial Fire Trucks. 

   FIELD OF THE INVENTION 
   The present invention generally relates to aerial fire trucks and particularly to an outrigger obstruction detection system (OODS) to allow the driver to park the truck in a position where no obstructions will be in the way of the outriggers when the outriggers are extended. 
   BACKGROUND OF THE INVENTION 
   When the aerial apparatus of a fire truck is used, outriggers are extended to provide support for the chassis by widening the support base of the fire truck. When the aerial fire truck arrives on a scene, the driver of the fire truck must position the fire truck so that there are no obstructions to prevent the outriggers from fully extending. 
   The task of positioning an aerial fire truck at the scene of a fire/emergency involves many factors, including but not limited to the location of the fire/emergency; overhead obstacles such as trees, guide wires, electric wires, telephone wires, overhanging structures; obstacles such as telephone poles, vehicles, garbage dumpsters, buildings, and curbs, sidewalks, and slopes in terrain. Each of these obstacles need to be quickly evaluated by the driver of the aerial fire truck in order to effectively and efficiently position the truck in order to employ the aerial device to attack the fire/emergency. 
   One of the major complaints of fire fighters is the inability to effectively position the aerial fire truck to ensure that the outrigger will not be obstructed when being extended. It is important that the outriggers be fully extended. If the outrigger cannot be fully extended, the safety features of the aerial device will have to be overridden in order to operate the aerial device. This potentially puts the fire fighters in jeopardy, along with those being rescued. 
   In order to set up an aerial fire truck at the scene of a fire, the driver of the fire truck must position the truck in such a way as to not obstruct the outward movement of the outriggers. Currently, this is accomplished through experience of the driver visually determining whether an obstruction exists. If the driver was not correct in his judgment, the truck might have to be repositioned after a failed attempt to fully extend the outriggers. This increases the response time of the fire fighters to attack the fire/emergency. In other words, someone&#39;s house continues to burn; someone trapped in the building might be exposed to the fire/carbon monoxide/smoke longer; or someone might be swept downstream by the rushing currents because they could not hang on any longer. This could all be due to the environment surrounding the fire/emergency and the false judgment of the driver of the aerial fire truck. 
   Time is of the essence when emergency services such as fire fighters are called to a fire/emergency. If the aerial fire truck arrives on the scene, stops, and then must be repositioned because the initial stopping point has obstructions preventing the outriggers from fully extending, valuable time is lost which can lead to unnecessary property damage, bodily injury and even death. 
   Therefore, it would be advantageous for the fire fighters to ensure that the aerial fire truck is positioned at the scene so that there are no obstructions to prevent the outriggers from extending. Further, it would be advantageous to have a system and method for ensuring that obstructions do not prevent the outriggers from being extended thereby preventing valuable time from being wasted due to repositioning the aerial fire truck. 
   SUMMARY OF THE INVENTION 
   The advantages of the invention are provided by an outrigger obstruction detection apparatus for an aerial fire truck having an outrigger comprising an outrigger zone defined by an area occupied by the outrigger when the outrigger is in an extended position; a sensor carried by the fire truck for detecting an obstruction within the outrigger zone; and a warning indicator operatively associated with the sensor so that the warning indicator is actuated when the sensor detects an obstruction in the outrigger zone; a method for detecting outrigger obstructions for an aerial fire truck having an aerial apparatus comprising the steps of detecting whether an obstruction is present within the outrigger zone defined by an area occupied by an extended outrigger of the fire truck through use of a sensor; and actuating a warning indicator carried by the fire truck if an obstruction is detected within the outrigger zone; an outrigger obstruction detection apparatus comprising an aerial fire truck having an aerial apparatus; an outrigger carried by the aerial fire truck having an extended position and a retracted position; an outrigger zone defined by an area occupied by the outrigger when the outrigger is in the extended position; a sensor carried by the fire truck for detecting an obstruction within the outrigger zone; and a warning indicator operatively associated with the sensor so that the warning indicator is actuated when the sensor detects an obstruction within the outrigger zone; an outrigger obstruction detection apparatus for an aerial fire truck having an outrigger comprising a computer readable medium carried by the fire truck; a sensor in communications with the computer readable medium for detecting an obstruction within an outrigger zone defined by an area occupied by the outrigger when the outrigger is in an extended position; a warning indicator in communications with the computer readable medium; and a set of computer readable instructions embodied in the computer readable medium for receiving a detection signal from the sensor when an obstruction is detected within the outrigger zone and actuating the warning indicator once the detection signal is received. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be more readily understood by referring to the specification and the drawings that are a part thereof. 
       FIG. 1  is a perspective view of an aerial fire truck that has arrived at the scene of an emergency showing outriggers extended and a potential obstruction at the left of the truck; 
       FIG. 2  is a top view of an aerial fire truck that has arrived at the scene of an emergency showing outriggers extended and a potential obstruction at the left of the truck; 
       FIG. 3  is a top view of an aerial fire truck that has arrived at the scene of an emergency showing an obstruction at the left rear of the truck preventing the left rear outrigger from being full extended. 
       FIG. 4  is a is a top view of an aerial fire truck showing the outriggers retracted and the outrigger zones; and, 
       FIG. 5  is a schematic of the invention. 
       FIG. 6  is a perspective view of an aerial fire truck. 
       FIG. 7A  is a side view of a pivotal mount for a sensor. 
       FIG. 7B  is a side view of a pivotal mount for a sensor. 
       FIG. 8  is a side view of a pivotal mount for a sensor. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1  depicts an aerial view an aerial fire truck  19  that has just arrived at the scene of the fire. It is up to the driver to position the aerial fire truck so that the truck&#39;s outriggers can be fully extended in order to safely operate the aerial device. Left front outrigger  20   c  and left rear outrigger  20   d  are shown in the extended position. Outriggers provide stabilization for the fire truck when the aerial apparatus is in operation, and particularly, when the aerial swings to a side of the fire truck chassis. 
   Mounted next to each outrigger are ultrasonic sensors shown as  22   c  and  22   d  on the left side of the fire truck. There are potential obstructions  24   a  and  24   b  located near the rear of the aerial fire truck  19  in potential conflict with the outrigger  20   c  and  20   d  from being extended. In the preferred embodiment, ultrasonic sensors are used. Other sensor technologies, such as lasers, tactile sensors, and infrared sensors were also considered, but found to have limitations or unneeded complexity to accomplish the same task as the ultrasonic sensors. 
     FIG. 2  depicts the fire truck from the top. Fire truck  19  is shown arriving at the scene of the fire/emergency. Outriggers  20   a  through  20   c  are shown extended to provide support for the fire truck when the aerial is in operation. However, outrigger  20   d  cannot be extended due to obstruction  24   b  which prevents outrigger  20   d  from fully extending. Therefore, the fire truck needs to be repositions so that outrigger  20   d  can be fully extended and not be obstructed by obstructions  20   a  or  20   b . Sensors  22   a  through  22   d  are shown carried by the fire truck and positions in close proximity to outriggers  22   a  through  22   d.    
     FIG. 3  shows the top of the fire truck (aerial apparatus not shown) with the outriggers in a retracted position. Sensor  22   a  is able to determine whether there is an obstruction within outrigger zone  28   a . Outrigger zone  28   a  is an area defined by the space occupied by outrigger  20   a  when outrigger  20   a  is fully extended. As shown, there are no obstructions within outrigger zone  28   a  preventing outrigger  22   a  from being fully extended. Therefore, sensor  22   a  detects no obstructions in outrigger zone  28   a . Similarly, sensors  22   b  and  22   c  are able to detect whether obstructions exist within outrigger zones  28   b  and  28   c  respectively. As shown, there are no obstructions within outrigger zones  28   b  or  28   c . However, obstruction  24   b  is contained within outrigger zone  28   d  so that sensor  22   d  detects that there is an obstruction within outrigger zone  28   d  preventing outrigger  22   d  from being full extended. It should be known that the sensor beams  18   a  through  18   d  need not cover the same area as outrigger zones  28   a  through  28   d , respectively. Rather, the outrigger zone need only be contained within the sensor beam and operatively configured to detect an obstruction within the outrigger zone. 
   For example, ultrasonic sensors output is dependent on the comparison at the time taken for an echo to return. The distance to an object is proportional to the distance to the object. Further, an ultrasonic proximity sensor has output whose intensity can be dependent on the distance of an object from the sensor. Therefore, an ultrasonic sensor, including a transducer or proximity sensor, can determine whether an object is within a certain distance and therefore within the outrigger zone. 
   Referring to  FIG. 3 , sensors  22   c  through  22   d  may have sensing zones shown as  18   a  through  18   d , respectively. However, the sensors can be configured to determine if an obstruction is within the outrigger zone, a zone smaller than the area of the sensing zone. 
     FIG. 4  is a schematic of the invention. Sensors  22   a  through  22   d  are shown associated with outrigger zones  28   a  through  28   d  respectively. The sensors are connected to a power supply  20  and can have a switch  22 . Warning panel  24  can have warning indicators  26   a  through  26   d  which can be connected to the sensors. Warning indicators  26   a  through  26   d  are in communications with sensors  22   s  through  22   d  respectively so that when an obstruction is detected within the outrigger zone, the associated sensor signal is used to actuate the corresponding warning indicator on the warning panel. Further, the warning panel can have a representation of a view of the fire truck approximating the location of the outriggers in relation to the fire truck chassis. The warning indicators can be located on the warning panel so that when actuated, the fire truck driver is provided with an indication of which outrigger zone contains the obstruction and therefore can reposition the fire truck accordingly. 
   After the driver has been warned of the obstruction  24   d  by actuated warning indicator  26   d , corrective action can be employed such as pull the aerial fire truck  19  forward until obstruction  24   b  is not longer detected within outrigger zone  28   d . Clearance of obstruction  24   d  is completed when sensor  22   d  no longer detects obstruction  24   b . Warning indicator  26   d  on warning panel  24  is no longer illuminated, providing a “clear” state to the driver. 
   Switch  22  can be operatively associated with the parking brake of the fire truck so that switch  22  is closed when the parking brake is applied. Switch  22  can be operatively associated with the power system of the aerial apparatus so that when power is applied to the aerial apparatus, switch  22  is closed. A relay  30  can be included so that the sensor signals can be transmitted to relay  30  to actuate the corresponding warning indicator when the sensor detects an obstruction in the respective outrigger zone. 
   Computer readable instructions embodied in a computer readable medium as well as electrical circuitry can be operatively associated with the sensors so that when the sensor detects an object within its sensing zone, the computer readable instructions determine whether the object is within the outrigger zone and the corresponding warning indicator can be actuated indicating that an obstruction exists within the outrigger zone. 
     FIG. 5  shows a top view of the fire truck when the fire truck has been positions so that there are no obstructions in the outrigger zones  28   a  through  28   d . When the warning panel indicates that there is an obstruction within an outrigger zone, the driver of the fire truck can reposition the fire truck until the previously actuated warning indicator no longer is actuated thereby representing that no obstructions re present in the outrigger zones  28   a  through  28   d.    
   Ultrasonic sensors emit sound pulses through a diaphragm on the front of the sensor. The sound pulses emanate from the sensor in a predetermined pattern known as the sensor beam. When an object passes through the sensor beam, the sound pulses are reflected back to the sensor diaphragm. The sensor&#39;s electronics monitor the pulse reflection to determine an object is obstructing the beam. When an obstruction is detected, the sensor sends a signal output to representing that the sensor has detected an object within the sensor beam. 
   A relay can be used between sensors  22   a ,  22   b ,  22   c  and  22   d  and the warning indicators  28   a ,  28   b ,  28   c  and  28   d . The relay is used to convert the low current sensor output to a high current signal output which can be used to actuate the warning indicators. 
     FIG. 6  illustrates a perspective view of an aerial fire truck showing the outriggers in the retracted position. In one embodiment, sensor  22   c  is carried by the fire truck in close proximity to an outrigger plate  32   c . Outrigger plate  32   c  covers the outrigger assembly and is generally flush with the side of the fire truck when the outrigger is in the retracted position. In another embodiment, sensor  22   c  is mounted on the outrigger place  32   c . Therefore, the sensors can also be mounted in close proximity to the outrigger plate or on the outrigger plate itself. 
   The actual location of outriggers may vary depending on the type and construction of the outrigger assembly employed on the aerial fire truck. Further, in one embodiment, there may be only two outrigger assemblies on the aerial fire truck. 
   Referring to  FIG. 7A , sensor  22   a  can be mounted on a pivotal mount. By mounting the sensors on a pivoting mount, the sensors can be positioned so that the sensors sensing areas overlaps that of the outrigger zone. The sensors can be positioned so that the sensor beam path intersects the outermost point of the space occupied by the outrigger when fully extended. In one embodiment, base bracket  44  can be secured to the faire truck. Rotating member  42  can be connected to base bracket  40   a  and  40   b  ( FIG. 7B ) so that the rotating member can be secured in place or allowed to rotate based upon tightening or loosening of screws  40   a  and  40   b . Swivel  46  allows the sensor to swivel and in combination with the movement allowed by the rotating member, the sensor can be positioned in two different planes. 
   In one embodiment, base socket  50  is secured to the fire truck. Ball joint  48  is received in the base socket and allows the sensor to be positioned in two different planes. Swivel  46  can also be used to mount sensor  22   a  to ball joint  48  to allow even further range of positions of the sensor. 
   In one embodiment, the mount consists of a vehicle mounting bracket, sensor mount bracket and two locking nuts. The “L” shaped vehicle mounting bracket has curved slots on each face, with a hole on the face that mates to the surface of the fire truck  19 . The “L” shaped sensor mounting bracket has a round hole to accept the sensor on one face, with two through holes on the other face to mate to the vehicle mounting bracket. Two locking nuts are positioned on the sensor  22   a ,  22   b ,  22   c  and  22   d  and on each side of the face with the through hole on the sensor mounting bracket. This configuration allows the sensor  22   a ,  22   b ,  22   c  and  22   d  to be positioned in 2 different planes, thereby achieving the ability to point the sensor  22   a ,  22   b ,  22   c  and  22   d  along the desired path. In one embodiment, this mount is affixed to the body via hardware, in close proximity to the outrigger assembly, and approximately 2 feet off the ground. 
   The computer readable instructions can receive a signal from the sensors and then actuate the warning indicator. Further, a parking brake can send a signal to the computer readable instructions so that the computer readable instructions will only actuate the warning indicator according to the sensor signal if the fire truck parking brake is engaged. The power system of the aerial truck can also be in communication with the computer readable instructions so that the warning indicator will only be actuated when power to the aerial apparatus is applied. Further, the outrigger actuator can be in communications with the computer readable instructions so that the outrigger will not be extended if the sensor detects an obstruction in the outrigger zone. In one embodiment, sensors  22   a ,  22   b ,  22   c  and  22   d  can be calibrated to send a signal when an object is detected at a known point in space. In other words, the sensing distance can be set by calibrating the sensor. 
   In operation, the fire truck operator maneuvers the aerial fire truck  19  into a setup position. Power is applied to the sensors. In one embodiment, sensors,  22   a ,  22   b ,  22   c  and  22   d  start emitting sound pulses at each outrigger location. If an object is detected in any of the outrigger zones, the corresponding sensor will send a signal to a relay. The relay will switch to a normally closed position and send an output to the warning indicator  28   a ,  28   b ,  28   c  or  28   d , informing the operator of an unsafe setup position. The vehicle can then be repositioned until no obstructions are detected. 
   In one embodiment, programmable input/output module is used in place of the relay. The programmable I/O module provides power to the ultrasonic sensors  22   a ,  22   b ,  22   c  and  22   d , controls inputs from the sensors, and provides outputs to the warning indicators  28   a ,  28   b ,  28   c  and  28   d . The input/output module has built in circuit protection for each output. User defined parameters are programmed to control the switching logic. 
   In operating, if an object is detected in any of the outrigger zones, the corresponding sensor will send a signal to the programmable input/output module. The programmable input/output module is programmed to send an output to the appropriate warning indicator  28   a ,  28   b ,  28   c  and  28   d  informing the operator of an unsafe setup position. 
   While a preferred embodiment of the invention has been described using specific terms, such description is for illustrative purposes only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims.