Patent Document

CROSS-REFERENCE TO RELATED APPLICATION(S) 
     The present application derives priority from U.S. provisional application Ser. No. 60/874,172 filed 7 Dec. 2006. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a remote control model aircraft, and more particularly to a remote control model aircraft having laser tag shooting capabilities. 
     2. Description of the Background 
     Radio-controlled (RC) aircraft are utilized for scientific, government, and military purposes to simulate actual combat in a safe manner or to act as spy planes. RC aircraft are also a growing hobby among model airplane enthusiasts. RC aircraft can be controlled remotely with a hand-held transmitter and receiver within the crafts. Prior art RC craft also incorporate other advanced technological devices to enable hobbyists to enjoy other gaming capabilities, such as laser tag. There has been one known patent effort in this regard. 
     United States Patent Application No. 20050186884 by Evans filed on Feb. 18, 2005 shows a remote control game system with remote control vehicles where one generates an offensive laser signal and in response, the other generates a hit signal. Responsive to the hit signal the vehicle will degrade operation of its offensive components. However, this does not closely simulate actual combat which typically involves releasing smoke and ejecting the pilot from the plane after the plane incurs a number of hits. 
     Thus, there remains a need for an RC model aircraft with laser tag shooting action including a hit/tag sequence that simulates highly realistic actual combat within the Association for Model Aviation (AMA) guidelines. 
     SUMMARY OF THE INVENTION 
     It is, therefore, the primary object of the present invention to provide a radio-controlled aircraft system with laser tag shooting action. 
     Another object of the present invention is to provide a radio-controlled aircraft system having firing and hit sequences with accompanying theatrical, physical effects including release of smoke and ribbons, and ejection of a pilot. 
     Yet another object of the present invention is to provide a radio-controlled aircraft system that realistically simulates air combat. 
     Still another object of the present invention is to provide a radio-controlled aircraft system that adapts a safe method of simulation. 
     Another object of the present invention is to provide a radio-controlled aircraft system that is fabricated of materials providing an appropriate degree of flexibility, resiliency, durability, and longevity. 
     An additional object of the present invention is to provide a radio-controlled aircraft system that may be relatively economically manufactured and sold to provide for widespread use. 
     These and other objects are accomplished by a radio-controlled system that introduces the challenge and excitement of laser tag to the hobby of model R/C aircraft. A transmitter and receiver are each installed in at least two separate RC aircrafts for simulated dogfight-style air combat. In use, each operator controls the near infrared (NIR) laser transmitter on their aircraft from their handheld RC controller. They maneuver for aim until the transmitter on one aircraft emits a laser-infrared light beam to the receiver on the other aircraft(s) to score a hit. The receiver activates a first servo to move an arm, which releases a model aircraft door behind which there are ribbons. The ribbons escape from the aircraft wings to show the hit. An optional second servo operates a smoke screen and ejects a pilot to more closely simulate actual combat. The system also includes a sound signaling device with light bulbs, and can include an online simulation component. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other objects, features, and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments and certain modifications thereof when taken together with the accompanying drawings in which: 
         FIG. 1  is a diagrammatic view of a radio-controlled model aircraft system  1  having laser tag shooting action according to one exemplary embodiment of the present invention. 
         FIG. 2  illustrates the pilot ejection assembly  6 . 
         FIG. 3  is a perspective view of a conventional servo. 
         FIG. 4  is a diagrammatic view of an exemplary control arm attachment  33  for releasing the ribbons. 
         FIG. 5  (A-C) is a sequential schematic illustration of the first  10  and second receptacles  28  opening. 
         FIG. 6  (A-B) is a sequential perspective illustration of the receptacles  10 ,  28 ,  15  in closed position (A) and in an open position (B). 
         FIG. 7  is an exemplary circuit diagram of processor  3 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIG. 1  is a diagrammatic view of a radio-controlled model aircraft system  1  having laser tag shooting action according to one exemplary embodiment of the present invention. The system  1  generally comprises one or more model radio-controlled (RC) aircraft  2  with accompanying radio controllers  20 , each aircraft  2  being capable of laser tag shooting action  1  including a hit/tag sequence that simulates highly realistic actual dogfight-style combat, within the Association for Model Aviation (AMA) safety guidelines, by releasing smoke and ribbons  24  and ejecting a pilot assembly  6  to indicate the end of battle. The handheld radio controllers  20  are each conventional and include a pair of joysticks for controlling flight of the aircraft, plus at least one auxiliary firing control button. A variety of suitable handheld radio controllers  20  exist which include acceptable auxiliary control switches that will serve as an auxiliary firing control button. 
     As seen in the enlarged diagrammatic view of  FIG. 1 , each aircraft  2  further comprises a conventional model aircraft chassis with wings, gas engine, cockpit, and motion-control servos for controlling flight. In accordance with the present invention the aircraft is equipped with on-board processor  3 , battery  7 , an RC receiver and plurality of auxiliary servos as will be described for implementing the above-described hit/tag sequence. 
     Each RC aircraft  2  is additionally equipped with a near infrared (NIR) receiver  4  mounted aft of the cockpit, underneath the fuselage, and electrically connected to the processor  3 . A NIR light source  12  such as a NIR laser diode is mounted externally atop one of the wings and is connected to the processor for selective illumination. The NIR light source  12  may be activated from the associated radio hand-held transmitter  20  and, when activated the light source  12  pulses on and off. The NIR receiver circuit  4  (described in further detail in reference to  FIG. 3 ) on one airplane  2  is operative to respond to the frequency of the modulated pulse bursts of infrared light from the NIR light source  12  emanating from another airplane  2 . Thus, a hobbyist controlling one airplane  2  from hand-held transmitter  20  can burst their NIR light source  12  during a realistic dogfight to achieve a laser tag shooting action upon the other airplane  2 . Upon receiving a predetermined number or intensity of hits the other airplane  2  completes a hit sequence with accompanying theatrical, physical effects including release of smoke and ribbons, and ejection of the pilot. The net effect is a very realistic air combat simulation played out vicariously through multiple RC airplanes. 
       FIG. 2  illustrates the pilot ejection assembly  6  in more detail, and this includes a pilot doll  18  having a backpack  19  for containing a parachute  20 , the strings  21  of a parachute  20  being fixedly connected within the backpack  19 . In order to avoid litter, it is preferable to make the pilot doll  18  of biodegradable material such as paper mache&#39; and the parachute  20  of tissue paper so as not to clutter trees and fields. A cutout  5  in the fuselage ( FIG. 1 ) houses the pilot ejection assembly  6 , and within the cutout the pilot doll  18  sits atop a compressed spring  27 . Within the fuselage, a servo mechanism (servo)  14  is connected to a pull pin release  26  for releasing the compressed spring  27 . A push rod  17  is connected at one end to the servo arm  34  and is slidably inserted through a push rod guide  23  mounted in the fuselage. Any commercially available push rod guide  23  will suffice including the Dubro™ Micro Pushrod Guide. The push rod  17  extends there through and the tip is inserted into a release block  26 , the release block being held back thereby. Various manufacturers make spring loaded pull pins which can be used with the present invention, including the Tite-Lok® spring-loaded pull pin. The push rod  17  comprises rubber, nylon, or any other tensile material that provides the requisite force and resistance to eject the pilot assembly  6  along with the pull pin  26  in a controlled, smooth movement with minimum friction. A nylon push rod  17 , including the Sullivan Flex Gold-N-Rod, may be utilized to reduce thermal expansion and prevent radio interference, while still providing strength, flexibility, and lightness of weight. The release block  26  is connected by string or the like to the spring  27  and so long as the push rod  17  remains inserted in the release block  26  the spring  27  remains in compression and the pilot doll  18  sits. However, when the servo  14  is activated it pulls the push rod  17  tip out of release block  26  and releases the spring  27 . In this manner the pilot ejection assembly  6  automatically ejects the doll  18 , backpack  19  and furled parachute  20  at the end of an unsuccessful laser tag sequence. The cutout  5  may also include ribbons which can be released along with the pilot assembly  6 . 
     Optionally, a light display  8  (such as an LED display) can be attached aft of the cockpit, underneath the fuselage to visually simulate adverse hits, and a sound signaling device  9  (e.g. a buzzer) can be included for audio effects. Both the sound signaling device  9  and light display  8  are electrically connected to the processor  3  for selective activation thereby. Mini EZ Connectors™ are conventional wire terminals that allow convenient retrofit electrical connection of the components of each airplane  2  and is generally intended that the above-described electronics be retrofit to an existing RC airplane. 
     In addition to the pilot ejection mechanism  6 , ribbons  24  are released from first, second, and third receptacles  10 ,  28 ,  15  built into right and left forward wings and/or the fuselage. The location and size of the receptacles is a matter of design choice and may be varied based on the size of the airplane  2 , and weight distribution considerations. A lid  29  is engaged by a similar pull pin release mechanism and pops open to release the ribbons  24 . These receptacles  10 ,  28 ,  15  are described in further detail with respect to  FIGS. 5 and 6 . All ribbons  24  are yellow and red to signify fire, to more realistically simulate combat. 
     A near infrared (NIR) light source  12  is mounted on the topside of the right forward wing and is aimed forward to transmit a laser to a receiver  4  on an opposing aircraft  2 . The light source  12  is preferably a laser diode, including for example the SDL 6300 Series High Brightness NIR Laser Diodes. The light source  12  is under operator-control from hand-held transmitter  20  and when activated the light source  12  pulses on and off. The receiver circuit  4  (described in further detail in reference to  FIG. 3 ) is operative to respond to the frequency of the modulated pulse bursts of infrared light from the light source  12  of another airplane  2 . The light source  12  and receiver  4  are electrically connected to the power source  7 . Given good agility and aim, the infrared (IR) light beam pulsing from the light source  12  on one RC plane  2  strikes the receiver  4  of another RC plane  2 . The maximum range of the light source  12  is 25 feet, in order to simulate a more realistic dogfight where warring fighter planes typically have to be in close proximity to shoot at each other. The receiver  4  may also receive the motion control signals from the hand-held transmitter  20  which controls the motion of that particular plane  2 . 
     The receiver  4  is connected to the processor  3  which registers “hits” (optical signals input to receiver  4  at least five seconds apart). As described below, these hits cumulatively activate the servos to eject the pilot, release smoke or ribbons, and actuate lights and/or sound. Each hit is equivalent to winning a point in the game of laser tag. Every hit is part of a win sequence, similar to an actual battle. 
     The airplane  2  generally comprises two RC servos  13 ,  14 , one for actuating the pilot ejection assembly  6  and one for releasing the ribbons  24  from the wings and/or the fuselage. If preferred either one of the servos  13 ,  14  may be used to the exclusion of the other, and thus the hit sequence would be reduced accordingly. Various manufacturers make servos  13 ,  14  which can be utilized in constructing the present invention and include the following: Airtronics, Futaba, JR Radio, Hitec. 
       FIG. 3  is a perspective view of a conventional servo. Both servos  13 ,  14  are analog and comprise a DC motor  31  mechanically linked to a potentiometer  32 . Additionally, the DC motor  31  drives the servo output wheel  3  by gears  11 , all of which are assembled inside a plastic housing. The receiver  4  controls the servos  13 ,  14  based on the RF signals received from hand-held transmitter  20 . When a servo  13 ,  14  is commanded to rotate (by signals sent by the receiver circuit  4 ), the DC motor  31  is powered until the potentiometer  32  reaches the value corresponding to the commanded position. Servos  13 ,  14  are connected by three wires: ground (black), power (red), and control (white), and operate based on the control signals sent over these control wires. A first servo  13  can be mounted in the cockpit to provide appropriate weight distribution in the aircraft  2 . It is important for weight to be appropriately distributed and balanced in the plane  2  so that the plane  2  will fly well, and avoid crashing to the ground. 
     Servos  13 ,  14  each connect to a servo controller SCC 1  and SCC 2  via a control wire and servo controllers SCC 1  and SCC 2  both connect to the receiver  4  as described below. The angular motion of both the first  13  and second servos  14  will travel between the range of 0 to 180 degrees. 
       FIG. 4  is a diagrammatic view of an exemplary control arm attachment  33  for releasing the ribbons from first, second, and third receptacles  10 ,  28 ,  15 . Servos  13 ,  14  are connected to the lid  29  of first  10  and second  28  receptacles, via a control arm attachment  33 . Control arm attachment  33  is a lever attachment to the servo crankshafts. The attachments  33  may have one or more lever arms  34  to allow for multiple positions and also has a push rod  17  connected to the arm  34 . The arm  34  transfers leverage from the servos  13 ,  14  to the push rod  17 . Additionally, a hinged bracket  35  is mounted on the lids  29  of first  10  and second  28  receptacles and the other end of the push rod  17  is coupled thereto, to push/pull the lids  29 . Push rods  17  are attached to hinged brackets  35  by clevises, ball joints, or any other suitable pivoting couplings. If desired, the hinged bracket  35  may include a lever arm coupled to the push rod  17  for imparting proper leverage to the lid  29 . 
       FIG. 5  (A-C) is a sequential schematic illustration of the first  10  and second receptacles  28  opening in response to first and second pulses, respectively from movement of first servo  13 . Second servo  14  is mounted underneath the left forward wing in a similar manner. 
       FIG. 6  (A-B) is a sequential perspective illustration of the receptacles  10 ,  28 ,  15  in closed position (A) and in an open position (B). 
     With collective reference to  FIG. 5-6 , the receptacles  10 ,  28 ,  15  are initially closed ( 5 C and  6 A). When the first servo  13  experiences a first pulse or “hit” as at  5 (B), the servo  13  sets to its “neutral position” or 90 degrees, and moves the control arm attachment  33  which moves a guide plate  16  connected to the attachment  33  on one end and to a lid  29  on opposing end, upwards to push open the lid  29 . Each pulse subsequent to the first pulse will be sent to servo  13 ,  14  at least five seconds after the immediately prior pulse even if the receiver  4  is constantly irradiated to demarcate hits. The mechanism for this timing interval between pulses is explained in greater detail below. 
     As seen at  5 (B), a spring loaded tray  30  pushes ribbons  24  out of the receptacle  10 , as the lid  29  opens. The ribbons  24  housed in the first receptacle  10  are preferably 12″ long.  FIG. 6(B)  illustrates the open lid  29  of the receptacles  10 ,  28 ,  15 . 
     As seen at  5 (C), a second pulse moves the servo  13  from 90 to 180 degrees and opens the second receptacle filled with ribbons  24 . The ribbons  24  in the second receptacle  28  are preferably 36″ long. All ribbons  24  are yellow and red to signify fire, to more realistically simulate combat. The receptacles  10 ,  28 ,  15  may also house coal dust and/or release smoke along with the ribbons  24 . The bottom of receptacle  15  around the spring tray  30  can be omitted if only smoke rather than (48″) ribbons  24  are intended to be released. 
     A control arm attachment  33  connects the second servo  14  to the guide plate  16  attached to the lid  29  of receptacle  15 . When the second servo  14  experiences a third pulse, servo  14  moves from 0 to 90 degrees which moves the control arm attachment  33  and consequently the guide plate  16  moves upward to push open the lid  29  of the receptacle  15  and the smoke and/or ribbons  24  held therein escape. The control arm attachment  33  moves the lid  29  of the receptacle  15  with speed and precision. It is preferable to utilize a control arm attachment  33  including a servo arm  34  to provide the appropriate amount of control and direction. For example, a NELSON™ heavy duty SSA125 single servo arm can be utilized since it is a universal servo arm  34 , and can fit to any standard servo wheel with screws and elastic stop nuts. The NELSON™ heavy duty SSA125 single servo arm is robust and made from 1/16″ 2024T-3 aircraft grade aluminum. 
     A fourth pulse will move the second servo  14  from 90 to 180 degrees, which activates the pilot ejection assembly  6  (explained above) to expel the pilot  16  from the pilot receptacle  5  to signify the end of the battle. 
     The servos  13 ,  14 , receiver  4 , and light source  12  are electrically connected to the processor  3  and power source  7 . The electrical wiring to the central microprocessor  3  and power source  7  can be covered with a wire guide to protect the electronic components and also for greater aesthetic appeal. 
     When second servo  14  moves upon receiving the fourth pulse overall, the push rod  17  pulls the spring-loaded pull pin release  26 . The pull pin  26  then releases the pilot assembly connected to the spring end  27  of the pull pin  26 . The pilot assembly  6  is ejected from the pilot receptacle  5  and this signifies the end of the simulated battle; the loser of the battle being the plane  2  having its pilot assembly  6  ejected. 
       FIG. 7  is an exemplary circuit diagram of processor  3  showing the infrared receiver  4  connected to servo controllers SCC 1  and SCC 2  which output to servos  13 ,  14 . IR radiation input to the receiver  4  gives an output to first  13  and second  14  servos ( FIG. 1 ) to turn sequentially in 90 degree increments over 180 degrees with the first servo  13  completing its range of motion before the second servo  14  begins its motion. The servos  13 ,  14  and accompanying hit sequence is described in detail above. 
     The infrared receiver  4  circuit comprises a phototransistor Q 1  that is optically sensitive to IR radiation. Phototransistor Q 1  is connected across resistor R 1  to bias voltage V+ for quick response. When Q 1  receives IR radiation the power supply voltage V+ is sent to pin  2  of a timer T 1 , which is a conventional LM555 timer IC. Timer T 1  is an 8-pin V package, and so timer T 1  has eight connections (pins). Pin  1  is the ground (or common) pin and is connected to the circuit common (ground). Pin  2  is the trigger input pin, as it starts the timer T 1 . Pin  3  is the output pin which outputs a “high” clock pulse. The input at pin  2  sets the output at pin  3  to the high state. Pin  5  is a control voltage pin, which connects to a capacitor C 1  and discharges to the ground. Pin  6  is the threshold pin, and voltage (of 0.01 micro Farads) can be applied pin  6  to end the timing interval and reset the timer T 1 . Pin  7  is the discharge pin and it is connected to a resistor R 2  and to pin  6  which discharges to the ground. Pin  8  connects the timer T 1  to a positive supply voltage V+which must be between +5V and +15V. Typically, LM555 timers include a reset pin, which applies a low reset pulse (0V) to terminate the output pulse. However the reset input pin is not used in timer T 1  so that unwanted resetting does not occur. 
     Timer T 1  is set to operate as a conventional monostable oscillator in “one shot” operation. A timer in monostable mode is useful for creating a time period of fixed duration in response to external events, which in the present invention include the receiver  4  receiving IR radiation from a light source  12  on an opponent aircraft. The RC time constant of resistor R 2  in conjunction with capacitor C 1  is 5 seconds, and as such all inputs to Pin  2  of the timer T 1  are ignored for a period of 5 seconds. In other words, the receiver  4  is blind to IR radiation inputs that occur less than 5 seconds after the immediately prior input. This five-second delay allows for each “hit” (i.e. IR radiation input to receiver  4  which activates servos  13 ,  14 ) to be spaced apart, and thus creates a more realistic dogfight wherein an aircraft is typically fired at over a period of time before smoke is released and the pilot escapes from the airplane. 
     The output from Pin  3  of timer T 1  is a “high” clock pulse. This pulse is inputted into a test circuit TEST and to a counter CNT 1  which may be a type 4022 CMOS octal (divide by eight) counter. Test circuit TEST is used to test the transistor Q 7  and troubleshoot the following parameters: gain, leakage, breakdown, and switching time. These parameters should be monitored for purposes of maintenance and repair of the transistor Q 7 . Test circuit TEST includes a transistor Q 7  connected to a positive supply voltage V+. Transistor Q 7  is connected to resistors R 10  and R 11 . Resistor R 10  connects to ground and resistor R 11  is in series with a pushbutton switch S 1 , which is used for testing the circuit TEST. When the switch S 1  is open, little or no current will flow in transistor Q 7 . When the switch S 1  is depressed, the TEST circuit is closed, and current should flow in transistor Q 7 . An ohmmeter can be connected to the circuit TEST and used in conjunction with switch S 1  to test the gain and junction resistance of transistor Q 7 . Any commercially available pushbutton switch, including for example the JUDCO Manufacturing Inc. J-188-1 switch, may be utilized with the present invention. 
     Counter CNT 1  is a 4022 CMOS octal (divide by eight) counter with 16 connections (pins), and it is utilized to count the number of times the phototransistor Q 1  receives an optical signal. The clock pulse enters the counter CNT 1  at a Pin  3 . Pins  9 ,  2 , and  16  connect to a positive supply voltage V+which must be between +5V and +15V. Pins  8  and  10  connect to ground. Pin  1  connects to a reset circuit RESET. Circuit RESET resets the counter CNT 1 . Counter CNT 1  counts the number of hits, and it must be reset after each hit sequence is completed. Resetting can be accomplished by the reset circuit RESET or alternatively by the central microprocessor  3 . Circuit RESET includes a pushbutton switch S 2  connected in series to resistor R 3  which is connected to a transistor Q 2 , resistor R 4 , and a positive supply voltage V+. Pushbutton switch S 2  allows for manual resetting. Transistor Q 2  connects to ground. When pushbutton switch S 2  is manually depressed, it completes a low impedance connection from Pin  1  to ground, forcing circuit RESET and consequently counter CNT 1  to reset timing interval. Alternately if the switch S 2  is not manually depressed, the circuit RESET will activate after all of the output pulses QA-QD are sent and processed through servo controller circuits SCC 1  and SCC 2 . Pins  12 ,  13 ,  14 , and  15  output pulses QA-QD. Counter CNT 1  is preferably set up such that its outputs QA-QD start at zero and with each clock pulse increase in sequential order, remaining on until the cycle is completed or the reset button on the counter CNT 1  is manually pressed, at which time all outputs QA-QD return to zero again. Counter CNT 1  sends outputs QA and QB into the servo control inputs at transistors Q 3  and Q 4 , respectively of servo controller circuit SCC 1 . Counter CNT 1  sends outputs QC-QD into the servo control inputs at transistors Q 5  and Q 6  of servo controller circuit SCC 2 . The servo controller circuits SCC 1  and SCC 2  operate the servos  13 ,  14 , respectively based on which “hit” (i.e. first, second, third, or fourth) in the sequence occurred. Servo controller circuit SCC 1  comprises transistors Q 3  and Q 4  each connected across resistors R 5 , R 13  and R 6 , R 14  respectively, to bias voltage V+. Output QA from Pin  15  of counter CNT 1  is sent to transistor Q 3 , and output QB from Pin  14  is sent to transistor Q 4 . The output from transistors Q 3  and Q 4  is sent to Pin  2  of timer T 2 , after passing through diode D 1  connected in parallel to resistor R 9 . Servo controller circuit SCC 2  comprises transistors Q 5  and Q 6  each connected across resistors R 7 , R 15  and R 8 , R 16  respectively, to bias voltage V+. Output QC from Pin  13  of counter CNT 1  is sent to transistor Q 5 , and output QD is sent to transistor Q 6 . The output from transistors Q 5  and Q 6  is sent to Pin  2  of timer T 3 , after passing through diode D 2  connected in parallel to resistor R 10 . Diodes D 1  and D 2  restrict the direction of movement of charge carriers and thereby allow an electric current to flow in one direction, while blocking current in the opposite direction. Timers T 2  and T 3  are conventional LM555 timers IC operating in the astable mode. 
     Timers T 2  and T 3  are 8-pin V packages. Pin  8  connects both timers T 1  and T 2  to a positive supply voltage V+which must be between +5V and +15V. Reset pin  4  is connected to resistors R 17  and R 18  of timers T 1  and T 2 , respectively. Pin  1  is the ground (or common) pin and is connected to the circuit common (ground). Pin  5  control voltage at 0.01 microFarads. Pin  7  is the discharge pin, and pin  6  is the threshold pin which connects to input pin  2  of timers T 2  and T 3 , respectively. Pin  3  is the output pin which outputs pulse signals to servos  13 ,  14 , in order to control their motion. 
     When QA-QD are low, transistors Q 3 -Q 6  are off and only resistors R 9  and RIO, along with their respective capacitor (C 2  and C 3 ) determine the RC constant. The resistance of R 9  and R 10  is 2.9 kiloOhms. These chosen resistance values yield a low output lasting 2 ms. The resistance value of R 17  and R 18  is 0.5 kiloOhms. The values chosen for resistors R 17  and R 18  together with resistors R 9  and R 10  and capacitors C 2  and C 3  give a timer output that is high for 20 ms. When the counter CNT 1  outputs a high charge QA, transistor Q 3  is switched on and resistor R 13  is in parallel with resistor R 9  and reduces the time constant of the low output of the timer T 1  to 1.5 ms. When QB is high, transistor Q 4  is activated and resistor R 14  is in parallel with resistors R 9  and R 13 , further reducing the time constant to 1 ms. The same operation is carried out with the second servo controller circuit SCC 2  when QC and QD are high. Second controller circuit SCC 2  only operates after the function of SCC 1  is complete. When the second controller circuit SCC 2  completes its operation, the counter CNT 1  in the receiver  4  resets. Thus, the next optical pulse that Q 1  receives will operate SCC 1  and hence first servo  13 . 
     The timers T 2  and T 3  take in voltage at Pin  2  and generate output pulses at Pin  3  which are sent over the servos&#39;  13 ,  14  control wires which connect to servo controller circuits SCC 1  and SCC 2 . The inner mechanics of the servos  13 ,  14  control the position of servos  13 ,  14  in response to the output pulses. 
     When phototransistor Q 1  is pulsed with constant IR radiation, servo  13  will move 90 degrees; five seconds later it will move another 90 degrees to complete its motion; five seconds later the second servo  14  will move 90 degrees, pause another 5 seconds, and then servo  14  will move another 90 degrees, thereby completing the function of the receiver circuit  4 . Phototransistor Q 1  can receive constant or intermittent pulses, however the minimum amount of time between servo motions is 5 seconds. Q 1  can receive IR, move first servo  13  90 degrees, then 10 seconds later be irradiated again and servo  13  will move another 90 degrees. However if Q 1  is irradiated and servo  13  moves 90 degrees, the receiver circuit  4  will ignore any subsequent pulses for 5 seconds. After a five-second interval has passed, servo  13  will move from 90 to 180 degrees to complete its motion. 
     The theatrical smoke release from receptacle  5 , ejection of the pilot assembly  6 , release of ribbons  24 , and lights  8  provides visual effects of firing and being tagged. The servos  13 ,  14  can be altered to provide for varied game play. In addition to providing entertainment, the above disclosed system  1  can also have military applications and function as a safe method of simulating realistic air combat. 
     The present invention can be constructed utilizing any type of RC model aircraft  2 . One can assemble the RC plane  2  entirely or buy an Almost Ready to Fly (ARF) plane or pre-assembled Ready To Fly (RTF) plane. Various types of ARF planes are sold and include Lanier RC, Carl Goldberg Products, Great Planes, and Sig Manufacturing. A number of different brands of RTF are also sold and may be utilized in constructing the present invention, including Great Planes, Hobbico, E-Flite, Hangar  9 , Grand Wing Servo-Tech, HobbyZone and ParkZone. The light source  12  and receiver  4  must both be on the same frequency so the plane  2  can be controlled. RC aircraft  2  in the USA utilize a 72 MHZ frequency band for communication. The radio of the light source  12  broadcasts on AM, FM using PPM or PCM. Each aircraft  2  should have a flight channel, or sub-channel (range of frequency) to determine which light source  12  to receive communications from. A crystal is put into the light source  12  to allow it to communicate at a specific sub-channel to match the receiver  4  in the aircraft  2 . This avoids transmitters  12  on different planes from trying to control the same craft  2 , and prevents a possible crash. 
     Having now fully set forth the preferred embodiment and certain modifications of the concept underlying the present invention, various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept. It is to be understood, therefore, that the invention may be practiced otherwise than as specifically set forth in the appended claims.

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