Abstract:
A firefighter training unit for simulating use of a fire extinguishing system, the unit including: a reel; a user-manipulable nozzle; a hose having opposite ends attached respectively to the reel and the nozzle and being partially wound around the reel, wherein rotation of the reel in a first rotational direction allows the hose to be unwound from the reel; a motor configured to drive the reel in a second rotational direction which causes the hose to be wound onto the reel; one or more devices for providing one or more output signals corresponding to one or more simulated operating conditions of the fire extinguishing system; and a controller configured to drive the motor in response to the one or more output signals so as to apply torque to the reel in the second rotational direction to simulate forces applied to the hose during operation of the fire extinguishing system.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates generally to equipment for training fire fighters and more particularly to firefighter training equipment that simulates real world conditions experienced by fire fighters in hazardous environments. 
       BACKGROUND OF INVENTION 
       [0002]    Firefighter training is typically an expensive and potentially dangerous task. Often the realism experienced in a training environment is significantly limited due to the inability of an instructor to recreate fire activity in a safe manner. 
         [0003]    Expensive hot fire training props are often in high demand and are limited to recreating the one scenario that they were developed for. Firefighter training is therefore limited in the variety of different scenarios that can be presented to trainee firefighters so that the value of training can diminish as the trainee becomes accustomed to the scenario that has been created. Such props also require the use of training vehicles, known as ‘pumpers’, to supply water to the training area, so that overall, significant man power is required to provide training opportunities to the fire fighters who are at the front line nozzles of firefighting equipment. 
         [0004]    The use of breathing apparatus for front line fire fighters in an internal, structural fire fight, combined with dragging a hose line, carrying break and entry gear and other firefighting tools is made significantly more complex by the addition of smoke, fire activity and potential full structural collapse. The physical exertion and exhaustion felt by the firefight after a period of activity cannot often be experienced in a training environment. 
         [0005]    There currently exists a need to develop firefighter training equipment that is relatively low cost, easy to deploy and adaptable to a number of training environments which nevertheless provides a high degree of realism in order to optimise the simulation experience. It would also be desirable to provide training equipment that ameliorates or overcomes one or more disadvantages or inconveniences of known firefighter training equipment. 
       SUMMARY OF INVENTION 
       [0006]    One aspect of the present invention provides a fire fighting training unit for simulating use of a fire extinguishing system that includes a hose and a liquid spray outlet connected to one end of the hose, for dispensing a fire extinguishing liquid, the firefighting training unit including 
         [0000]    a reel;
 
a user-manipulable nozzle;
 
a flexible and elongate member having opposite ends attached respectively to the reel and the nozzle and being at least partially wound about the reel, wherein rotation of the reel in a first rotational direction allows the elongate member to be unwound from the reel;
 
a motor configured to drive the reel in a second rotational direction, opposite to the first rotational direction which causes the elongate member to be wound onto the reel;
 
one or more devices for providing one or more output signals corresponding to one or more simulated operating conditions of the fire extinguishing system; and
 
a controller configured to drive the motor in response to the one or more output signals so as to apply torque to the reel in the second rotational direction to simulate forces applied to the hose during operation of the fire extinguishing system.
 
         [0007]    In one or more embodiments, a first operating condition is liquid flow rate through the nozzle, and a first device is a flow rate selector for selecting the liquid flow rate. 
         [0008]    In one or more embodiments, a second operating condition is liquid spray pattern, and a second device is a liquid spray pattern selector for selecting the liquid spray pattern. 
         [0009]    In one or more embodiments, a third operating condition is nozzle actuation to dispense a fire extinguishing liquid, and a third device is a nozzle actuation detector. 
         [0010]    Conveniently, any one or more of the above mentioned devices may be fitted to the user manipulable nozzle. 
         [0011]    In one or more embodiments, a fourth operating condition is rotational unwinding of the reel, and a fourth device is a rotational speed detector for detecting the rotational unwinding speed of the reel. Conveniently, the detector may be an encoder coupled to the reel. 
         [0012]    In one or more embodiments, the torque caused to be applied to the motor by the control is dependent on configuration data accessible by the controller. This configuration data may include any one or more of: 
         [0000]    fluid pressure, elongate member construction, elongate member length, floor surface and maximum force. 
         [0013]    In one or more embodiments, a fifth device is mounted to the nozzle for capturing image data during use of the firefighter training unit. 
         [0014]    In one or more embodiments, the elongate member is a flexible hollow tube, and may be made from canvas, plastic, rubber or other material typically used in the construction of firefighting hoses. 
         [0015]    In one or more embodiments, the firefighter training unit further includes electrical cabling extending within the tube between the one or more devices and the controller, for the purpose of transmitting data between the one or more devices and the controller. 
         [0016]    In one or more embodiments, the fighting training unit may further include a fluid supply, and at least one inflation device coupled to the fluid supply for inflating at least a portion of the tube to simulate pressurisation of the hose of the fire extinguishing system. Conveniently, the fluid supply may be a pressurised air container. In this case, the inflation device may be, for example, an air line extending within at least a portion of the tube. 
         [0017]    In one or more embodiments, the firefighter training unit includes one or more clamps to clamp the unit to a support surface, such as a floor. 
         [0018]    In one or more embodiments, the controller may include a processor and a non-transitory computer readable medium storing program instructions to cause the processor to compute to the torque to be applied to the motor and to apply that computed torque. 
         [0019]    Another aspect of the invention provides a method of operating a firefighter training unit according to any one or more of the preceding claims, the method including the steps of:
       receiving one or more output signals from the one or more devices, the output signals corresponding to one or more simulated operating conditions of the simulated fire extinguishing system; and   driving the motor in response to the one or more output signals so as to apply torque to the reel in the second rotational direction to simulate forces applied to the hose during operation of the fire extinguishing system.       
 
         [0022]    The fighting training unit can comprise a base station at which the reel, the motor and the controller are located and from which the elongate member and nozzle can be unwound from the reel. The base station can further include the fluid supply and the inflation device if provided. 
         [0023]    The motor can be an electric motor, AC or DC, or it can be a petrol or diesel motor. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0024]    Preferred embodiments of the present invention will now be described by way of non-limiting examples only with reference to the accompanying drawings in which: 
           [0025]      FIG. 1  is a perspective front view of a firefighter training unit according to one embodiment of the present invention; 
           [0026]      FIG. 2  is a perspective side view of the firefighter training unit of  FIG. 1 ; 
           [0027]      FIG. 3  is a schematic diagram of the firefighter training unit of  FIGS. 1 and 2  and depicts further details of an elongate member and user-manipulable nozzle forming part of that firefighter training unit; 
           [0028]      FIG. 4  is a schematic diagram sensors and servo control circuitry used to control operation of a servomotor connected to a hoses reel and air compressor forming part of the firefighter training unit shown in  FIGS. 1 to 3 ; 
           [0029]      FIG. 5  is a flow chart depicting various data processing steps performed by a controller forming part of the servo control circuit depicted in  FIG. 4 ; and 
           [0030]      FIG. 6  is a perspective view of firefighter training unit shown in  FIGS. 1 and 2  when in use during firefighting simulation activities by a user. 
       
    
    
     DETAILED DESCRIPTION 
       [0031]    Referring now to  FIGS. 1 and 2 , there is shown a firefighter training unit  10  for use in training firefighters in simulated hazardous conditions. The firefighter training unit  10  includes a housing  12  in which is mounted a reel  14 . A flexible hose  16 , or other flexible hollow tube or other flexible elongate member is wound around the reel  14 . In the embodiment depicted in  FIGS. 1 and 2 , the hose is made from material identical to hoses typically used by firefighters in extinguishing fires. However, in this embodiment water or other fire extinguishing fluid is not required to be pressurised within and expelled from the hose, and therefore in other embodiments of the invention different hollow or solid elongate members may be used. 
         [0032]    The firefighter training unit  10  further includes a motor  18  configured to drive the reel  14  in one rotational direction as well as a servo control circuitry  20  configured to drive the motor  18 . The firefighter training unit  10  also includes a user manipulable nozzle  22  attached or fixed to one end of the elongate member  16 . 
         [0033]    Depending on the environment in which it is used, it will be convenient to clamp the firefighter training unit  10  to the support surface upon which is rests by means of magnetic clamps  23  or like fixation devices in order to prevent lateral movement of the firefighter training unit  10  during simulation. 
         [0034]    The firefighter training unit  10  also includes a container  24  of pressurised air as well as a compressor  26 . As can be best seen in  FIG. 3 , in this exemplary embodiment an airline  28  extends within the hollow space inside the hose  16  between the nozzle  22  and reel  14 . The pressured container  24  and compressor  26  act to supply pressurised air to the interior of the hose  16  to inflate the hose during firefighting simulations. In that regard, the airline  28  may include a series of apertures (not shown) running along its length in order to enable the pressurised air to be expelled from the airline to the interior of the hose  16 . 
         [0035]    The firefighting training unit  10  also includes one or more devices for providing one or more output signals corresponding to one or more simulated operating conditions of the simulated fire extinguishing system. 
         [0036]    One or more of these devices may be user operable selectors for selecting the liquid flow rate, desired spray pattern of water or other fluid to be expelled from the simulated fire extinguishing system. In addition, one or more of the devices may detect another user action, for example, user actuation of a gate valve located on the nozzle  22  to expel liquid. In a real world fire extinguishing system, user actuated movement of a gate valve (see the gate valve  34  of  FIG. 3 ) from a closed to an open position will cause water to be expelled from the hose of the fire extinguishing system. 
         [0037]    Conveniently, such devices are mounted in the exemplary embodiment shown in  FIGS. 1 to 3  on the nozzle  22 . Both the flow rate selector  30  and the spray pattern selector  32  can be formed from rings mounted around the barrel of the nozzle  22  with encoders or industrial analogue potentiometers attached to the rings so as to detect the angular position in which each ring is placed by an operator. The gate valve position detector  40  (see  FIG. 4 ) can be a simple switch housed within the nozzle  22  and operable when the gate valve  34  or like mechanism is moved in the direction of the arrow  36  from an off to an on position. Electrical cabling  38  extends within the hose  16  between the spray pattern selector  32 , flow rate selector  30  and gate valve position detector  40 , and the controller  20  for data transmission. 
         [0038]    As can be seen in  FIG. 4 , the spray pattern selector  30  and flow rate selector  32  provide output signals corresponding—respectively to the spray pattern selected by an operator and the flow rate selected by an operator—to a controller  39 . The gate valve position detected by a gate valve position detector  40  is provided as another output signal to the controller  39 . A dead man switch or other actuation detector  42  may also be included in the nozzle  22  to provide a further output signal to the controller  38 , in this case being indicative of the grasping of the nozzle by a user. 
         [0039]    As can be also seen in  FIG. 4 , the motor  20  is connected to a hub  42  of the reel  14 , the hose  16  being wound around that hub  42 . Operation of the motor  20  is controlled by current from a servo amplifier  42 , which is in turn controlled by the controller  39 . An encoder  46  is coupled to the motor  20  to provide a position feedback signal to the controller indicative of the rotational speed of the reel, to the controller  39 . In that regard, a counter  48  is provided as part of the controller  39 , the frequency with which pulses are received from the encoder  46  being indicative of the rotational speed of the reel  14 . 
         [0040]    In one or more embodiments, a dynamic load  47  may be coupled to the motor  20  to restrict of the elongate member  16  out of the reel  14 . The dynamic load  47  assists in the delivery of step up or advancement forces at the hardware level and reduces the likelihood of damage to the electronics if a user pulls too fast on the elongate member  16 , which would otherwise create a generator-like effect that could introduce damaging voltages into the system. The dynamic load  47  may include a resistance connected in shunt across the motor  20 . 
         [0041]    Similarly, the air compressor  26  is coupled to one end of the hose  16  in order to pressurize air within the airline  28  and thereby inflate the hose  16 . The air compressor  26  is controlled by current from a servo amplifier  50 , which is in turn controlled by the controlled by the controller  39 . 
         [0042]    Input/output circuitry  52  is provided as part of the controller  39  in order to receive the output signals from the gate valve position detector  40 , flow rate selector  32 , spray pattern selector  30  and handle actuation detector  42 . In addition, a digital communication link  54  is provided as part of the controller  39  in order to send control signals to the servo amplifiers  44  and  50 . 
         [0043]    The controller  39  includes a processor  56 , read only memory or other non-transitory computer readable medium  58  storing program instructions to cause the processor to perform various computations described herein and to generate control signals to be transmitted to the servo amplifiers  44  and  50  from the digital communication link  54 . In performing its various operations, the processor  56  uses data stored in a volatile memory  60 , including configuration data  62  and one or more look up tables  64 . 
         [0044]    It will be appreciated that the gate valve position detector  40 , flow rate selector  32 , spray pattern selector  30 , handle actuation detector  42  and encoder  46  and merely examples of devices that may form part of the firefighter training unit  10  to provide one or more output signals corresponding to one or more simulated operating conditions of a real world fire extinguishing system. 
         [0045]    Another exemplary such device is a camera  66  (best seen in  FIG. 6 ), that may be conveniently mounted to the nozzle  22 , which provides an output signal to the controller  39  corresponding to images captured from the environment surrounding the firefighting training unit. This captured image data together with other data from the various devices forming part of the firefighter training unit  10  (such as the selected spray pattern) may be provided to a virtual reality system for incorporation into a display presented to a firefighter undergoing training in order to provide a more immersive training experience. As is the case with the detectors  32 ,  30 ,  40  and  42 , a connection between the nozzle mounted camera  66  and the controller  39  may be provided by means of the electrical cable  38  extending between the nozzle  22  and the controller  38  inside the hose  16 . 
         [0046]    Other exemplary devices include an inertial measurement unit  67  and infra-red tracking unit  69 . The inertial measurement unit  67  includes using a combination of accelerometers and gyroscopes, and possibly magnetometers, to track the pose and orientation of the user manipulable nozzle  22  during simulation so that an accurate representation of a jet of water coming from the user manipulable nozzle  22  can be generated by a virtual reality system. 
         [0047]    The infra-red tracking unit  69  includes a head with infra-red reception and transmission capacities. Such a unit enables a trainer to use simple active markers on walls or other surfaces in a training environment, for example, to differentiate different types of fires. 
         [0048]    In some embodiments, rather than relying upon the electrical cable  38 , wireless transmission/reception devices  71  and  73  may be provided to enable communication between the controller  39  and the various nozzle-mounted devices. 
         [0049]    In use, when a user grasps the nozzle  22  and moves away from the firefighter training unit  10 , the force applied by the hose  16  to the reel  14  causes rotation of the reel  14  in one rotational direction so as to unwind the hose from the reel. The controller acts to drive the servo motor  20  in response to the various output signals received at the controller  39 , taking into account configuration data (defining operational parameters of a fire extinguishing system to be simulated and various other parameters that may be required) to apply to torque to the reel  14  in the opposite rotational direction thereby to simulate the sum of one or more forces applied to the hose  16  during operation of the real world fire extinguishing system. 
         [0050]      FIG. 5  depicts a flow chart showing various steps performed by the controller  39  in the computation and application of a suitable torque to the reel  14  in order to simulate the sum of those various forces applied to the hose of the real world fire extinguishing system. After the firefighter training unit  10  and controller  38  are enabled at step  80 , the controller  39  initially accesses configuration data  62 , at step  82 . The configuration data  62  may include any one or more of fluid pressure, hose construction, hose diameter, hose length, floor surface properties (in order to determine a frictional force that may be experienced by a firefighter) and a maximum force/torque that may be generated by the servo motor  20  as a safety parameter. 
         [0051]    This configuration data  62  can be set up via an operator control panel (not shown). All selections can be made from one or more different groups of configuration data in order to simulate different types of fire extinguishing systems. 
         [0052]    At step  84 , the controller  39  interprets the presence of a firefighter by detecting handle actuation from an output signal provided by the dead man&#39;s switch  42 . When handle actuation is detected the controller  39  acts at step  86  to cause the air compressor  36  to inflate the hose  16  by means of the airline  28 . 
         [0053]    Before determining the value of the torque to be applied to the reel  14 , the controller  39  firstly detects the position of the encoder or industrial analogue potentiometer forming part of the spray pattern selector  30  fitted about the nozzle  22 , as well as the position of the encoder or analogue potentiometer of the flow rate selector  32  which is also fitted about the nozzle  22  (step  88 ). Once these two selections have been made at step  88 , the controller  39  accesses information stored in the look up table  64  and, at step  90 , computes a jet reaction force (also called nozzle reaction force) that would be applied to the nozzle of a real fire extinguishing system. 
         [0054]    In addition, at step  92 , the controller  39  determines whether the firefighter holding the nozzle  22  is moving away from the reel  14 . If this is the case, the controller  38  access the look up table  64  to determine the dragging (set up) force that would be required to drag a full hose over a floor surface of the type identified by the configuration data at step  94 . Once the jet reaction force  90  and the drag/friction force  94  have been computed, these two forces are summed by the controller  39 , and signals sent to the servo amplifier  44  in order to cause the servo motor  20  to apply a torque to the reel  14  in the opposite rotational direction to that caused by the firefighter moving away from the reel  14 , at step  96 . 
         [0055]    When the firefighter stops, and the controller  39  detects from the pulses provided by the encoder  46  that the reel rotational velocity has reduced to zero, the controller  38  will remove the drag/friction force computed at step  94  from the force applied by the motor  20 . 
         [0056]    It will be appreciated that the flow rate and spray pattern selected will have an effect on the jet reaction force calculated. In simple terms, a directional jet of fluid will generate more jet reaction force than will a fog or more dispersed spray pattern, whilst a higher flow rate will provide more jet reaction flow rate than a lower flow rate. A higher pump pressure (part of the configuration data) will also affect the jet reaction force, a higher pressure generating more force. A larger hose diameter will also allow for higher flow rates which will also affect the calculation of the jet reaction force. 
         [0057]    In various embodiments, a supervisory computer  100  may be connected by USB, Ethernet, wireless or other suitable connection means to the controller  20  to enable a trainer to control the real-time experience of a user of the firefighter training unit  10 . 
         [0058]    Finally it is to be understood that various modifications and/or additions may be made the above described embodiments without departing from the spirit or ambit of the invention as defined in the claims appended hereto.