Abstract:
An intergated secruity, tip-over, and turn signal system for a motorcycle. The system provides multiple-functions with one control unit and a simplified wiring network. The system provides vehicle turn signal control including automatic turn-off of turn signal lamps at the end of a turn. The systems monitors the lateral forces acting on the motorcycle and disables the turn signal lamps, starter system, and fuel system when a tip-over condition is detected. For theft deterrence and prevention, the system allows a rider to disable the vehicle starter and ignition systems while the vehicle is parked. Tamper sensors in the system activate turn signals and an audible alarm if tampering is detected.

Description:
The present invention relates to systems that provide turn signal control, tip-over shutdown, and security for motorcycles. More particularly, the present invention relates to a system that provides all of these functions, in a reliable manner, and with reduced wiring requirements. 
     A variety of accessory systems such as alarm and turn signal systems are installed on modern day motorcycles. These systems provide convenience and enhanced safety for riders of the vehicles. Tip-over systems, for example, are designed to increase safety by shutting off the motorcycle engine when the vehicle inclination reaches a dangerous level, such as might occur in an accident. As should be apparent, turn signal systems provide signaling to other vehicles and security systems provide theft deterrence. 
     While all of these systems are available for motorcycles, they are generally installed as separate systems, each with independent controls and wiring. The redundancy of controls and wiring creates problems. One problem is that each system takes up some of the limited space available on a motorcycle. This often results in crowding which makes installation and maintenance of the systems difficult. Another problem is that the wiring of each system is subject to physical failures such as connection faults. Since each system is independently wired, the number of possible failures multiplies with each accessory system installed. 
     In addition to the problems associated with accessory systems being designed as independent units, most tip-over, security, and turn signal systems do not operate satisfactorily. Present tip-over systems generally rely on pendulums and other mechanical devices to sense vehicle attitude. These types of systems are bulky, unreliable, and usually rendered non-functional when a sidecar is mounted on a motorcycle. Present turn signal systems allow riders to manually control signaling, but generally don&#39;t provide satisfactory automatic features. Present security systems generate audible alarms if vehicle tampering is sensed, but many may be bypassed by criminals with proper electronic equipment. 
     Accordingly, there is a need for an improved system that provides turn signal control, tip-over shutdown, and security for motorcycles. 
     SUMMARY OF THE INVENTION 
     The present invention provides a system for use in a motorcycle having turn signal lamps, turn signal switches, an engine, a starter, and an ignition system. The system includes a sensor such as an accelerometer that is designed to monitor the attitude of the motorcycle. The accelerometer is capable of detecting lateral forces acting on the vehicle. The output of the accelerometer is delivered to a processor. The processor includes a tip-over controller that analyzes the output of the accelerometer and shuts off certain vehicle systems such as the engine and turn signal lamps and disables the starter motor in the event a tip-over condition exists. Shutting off the engine and the turn signal lamps reduces spark sources, thereby reducing the possibility that fuel or other combustible liquids will ignite during a tip-over condition. Shutting off the engine also prevents continued powered movement of the rear wheel of the vehicle, which if allowed to continue during the tip over might injure the rider. 
     The processor is also programmed to control the motorcycle turn signal lamps and includes a turn signal controller. The turn-signal controller receives inputs from the turn signal switches and sends commands for actuation of the turn signal lamps. The turn-signal controller is operable to calculate the beginning of a turn of the vehicle and the end of a turn of the vehicle based on the output of the accelerometer and a vehicle speed signal. The turn-signal controller can turn off the turn signal lamps at the end of a turn. 
     The processor also includes a security controller operable to disable the vehicle engine and starter motor, detect alarm conditions, and activate alarm devices when an alarm condition exists. 
     These features as well as other advantages of the invention will become apparent upon consideration of the following detailed description and accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a block diagram of an electronic circuit embodying the invention; 
     FIG. 2 is a side view of a motorcycle equipped with the circuit of FIG. 1; 
     FIG. 3 is a mode state diagram of a power mode scheme embodying the invention; 
     FIG. 4 is a mode state diagram of a security system embodying the invention; and 
     FIG. 5 is a block diagram of a battery-backed siren module embodying the invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     An integrated security, tip-over, and turn signal system  10  is shown in FIG.  1 . The system  10  includes a processor  12 , which may take the form of a microprocessor or similar programmable device. In the embodiment shown, the processor is a 68HC08AS32 processor from Motorola, Inc. The system  10  is designed to be installed in a motorcycle  11  (FIG. 2) having such typical components as an engine  11 A, a fuel system (not shown), and an electric system (not shown). Preferably, the system is configured to interact with motorcycles equipped with standard communication networks such as the SAE (Society of Automotive Engineering) J1850 serial data bus (sometimes referred to as “bus-equipped vehicles”). However, the system  10  may be designed to operate in motorcycles without such a system. The processor  12  is placed in a housing  13  (FIG. 1) that also contains several other components, as discussed below. 
     The system  10  is powered by a battery  14 , which is coupled to a high voltage bias input Vcc of the processor  12 . The processor  12  senses the charge condition of the battery  14  through a line BATT. An ignition switch  16  is coupled to the battery  14  and, when turned to an ignition position I, delivers an ignition output through an IGN line to the processor  12 . Ignition of the vehicle occurs when the ignition switch  16  is in the ignition position I and a start switch  17  and run/stop switch  18  are closed by the vehicle rider. The ignition switch  16  also has an accessory position A and an off position OFF. 
     In addition to initiating ignition, the output signal on the IGN line acts as a wake-up for the processor  12 , shifting it out of a storage or stand-by power mode to an operational mode. The shifting between the storage power mode and the operational mode is part of a power moding strategy implemented by the system  10 . The strategy ensures that the system  10  always operates in a defined state based on information currently available to the system. It also ensures that the system transitions from one state to another based on predefined criteria. 
     The system  10  has an OFF mode, an ACCY mode (accessory mode), an IGN/STOP mode (ignition stop), and an IGN/RUN mode (ignition run). Each mode corresponds to different combinations of the ignition switch and the run/stop switch  18 . The various modes for the system  10  are set forth in Table A. 
     
       
         
               
             
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE A. 
               
             
             
               
                   
               
               
                 Power Mode Scheme 
               
             
          
           
               
                   
                 run/stop switch 
                 Ignition Key Switch Position 
               
             
          
           
               
                   
                 position 
                 OFF 
                 A 
                 I 
               
               
                   
                   
               
               
                   
                 STOP 
                 OFF mode 
                 ACCY mode 
                 IGN/STOP mode 
               
               
                   
                 RUN 
                 OFF mode 
                 ACCY mode 
                 IGN/RUN mode 
               
               
                   
                   
               
             
          
         
       
     
     The ignition signal the processor  12  receives through the IGN line allows the processor to distinguish between the OFF and IGN/STOP modes. However, based on this information alone, the processor is unable to determine when the IGN/RUN mode has been selected. In addition, the processor  12  cannot distinguish between the ACCY mode and the OFF mode. Therefore, the system  10  is designed to ensure that the processor  12  receives additional input to enable it to determine the proper mode. 
     The processor  12  is programmed to ensure that the current power mode is indicated by the input on the IGN line until additional information is received. Either an ignition module  20 , on non bus-equipped vehicles, or an engine control module (“ECM”)  20 A, on bus-equipped vehicles, acts as a power mode master (“PMM”) that provides the additional information. 
     One of the advantages of the present invention is that it is designed to operate on bus-equipped vehicles and non-bus-equipped vehicles. This is important because many existing motorcycles are not bus-equipped. Accordingly, the invention may be retrofitted on older motorcycles with relative ease. Before operation of the system  10  begins, the processor  12  determines the proper vehicle type so that it may interface correctly with other modules on the vehicle. To accomplish this, the processor  12  sets the vehicle type to bus-equipped whenever it is in the OFF mode. The first time the processor  12  enters the IGN/RUN mode, the processor determines the vehicle type. 
     The vehicle type determination is accomplished on non-bus-equipped vehicles using a feed back input IGN_ENABLE_FB from the ignition module  20 . In the embodiment shown, the IGN_ENABLE_FB signal from the module  20  is pulled high by an external voltage source V ext  when the ignition switch  16  is in the ignition position I, and the run/stop switch  18  is in the run position. When the IGN_ENABLE_FB signal is high, the processor  12  transitions to the IGN/RUN mode and the vehicle type is set to non-bus-equipped for the remainder of the current ignition cycle. Once the processor  12  has entered the IGN/RUN mode, it remains in that mode until a transition to the OFF mode occurs. The processor  12  cannot transition back to the IGN/STOP mode. 
     On bus-equipped vehicles, the PMM (which in the embodiment shown takes the form of the ECM  20 A) broadcasts the power mode that is presently valid and, therefore, the state of the run/stop switch  18 . Once the processor  12  receives the broadcast from the PMM, it sets the vehicle type to bus-equipped for the remainder of the current ignition cycle. In the event that the additional input from the ECM  20 A or ignition module  20  (as the case may be) is not received or is otherwise unacceptable to the processor  12 , the processor  12  operates in a back up mode. Specifically, if the processor  12  detects a loss of the IGN input, but still detects the PMM or the IGN_ENABLE_FB input, it remains in the last known power mode. The processor exits the backup mode when the IGN input is detected again or the additional power mode indicator (the IGN_ENABLE_FB or the PMM input) is lost. On bus-equipped vehicles, if a failure of the PMM occurs (a state of health or SOH failure), but an IGN input is still present, the processor  12  remains in the last known power mode. The processor  12  exits the backup mode when input from the PMM is detected again or the IGN input is lost. 
     The power moding strategy also provides for an optional STORAGE mode. If implemented, this mode is entered into after the processor  12  has been in the OFF mode for an extended period of time, such as 10, 30, or 60 days. When the processor  12  enters the STORAGE mode it shuts down the security controller (discussed below). Thus, the processor  12  no longer monitors for tampering or other alarm conditions. This reduces the current drain on the battery  14 . How the processor  12  transitions between the IGN/STOP, IGN/RUN, OFF, and STORAGE modes is summarized in the mode state diagram of FIG.  3 . As is apparent from FIG. 3, the STORAGE mode is exited when the ignition switch  16  is turned to an active position (the I or A position). 
     Referring again to FIG. 1, after ignition the ignition switch  16  returns to the accessory position A. In position A, power is provided to various vehicle systems, such as turn signals, as needed. Power is supplied to a cluster interface  21  which may take one of two forms; a cluster  21 A or a cluster  21 B, depending on the type of motorcycle in which the system  10  is installed. In a bus-equipped vehicle, the cluster interface  21  used is the bus compatible cluster  21 A which receives information from various other vehicle systems such as the engine control module  20 A and speed sensing systems (not shown). The information from those systems is delivered to a bus interface  23  and input to the processor  12  through a BUS line. For non-bus systems, an interface cluster  21 B is used. If desired, the interface cluster  21 B may be coupled to a vehicle speed sensor (not shown) and the output of the sensor delivered to the processor through line VSS. 
     The processor  12  may also be equipped with an auxiliary interface to receive input through an auxiliary line AUX_I/O. The auxiliary line AUX_I/O provides an interface to an external switch  25  to ground that is momentarily closed if an external sub system, such as an alarm of a security controller, discussed below, requests activity. As also discussed below, the AUX_I/O line is used to drive a security system telltale. 
     A left turn signal switch  30  and a right turn signal switch  32  provide input to the processor  12  through the lines LT_SW and RT_SW, respectively, when depressed by a rider. Input from these lines controls turn signal lamps and other features of the system  10 , as described further herein. 
     The processor  12  receives additional input from an accelerometer  40 . In the preferred embodiment the accelerometer is a C2EH1T model available from VTI-Hamlin. The accelerometer  40  measures lateral forces that act upon the motorcycle. The information provided by the accelerometer  40  is analyzed by the processor  12  and used to generate command signals to control various systems in the motorcycle. 
     The output of the accelerometer  40  is based on the movement and position of the vehicle. The position of the vehicle may be viewed as an inclination angle or lean angle of the motorcycle measured from a vertical vehicle position. In other words, an upright vehicle position is equal to a zero-degree vehicle inclination angle and a fully tipped over vehicle position is equal to a 90 degree vehicle inclination angle. The accelerometer  40  outputs a voltage that is proportional to the vertical component of the earth&#39;s gravity, as sensed by the accelerometer. Of course, centrifugal forces acting on the vehicle while it is in motion tend to counter act the gravitational forces acting on the vehicle. Thus, in steady state motion (such as when traveling around a curve at a constant speed) the output of the accelerator is zero or nearly zero. When the vehicle changes attitude or orientation, however, lateral forces acting on the vehicle are not fully cancelled by centrifugal forces acting on the vehicle. Thus, the accelerator senses such changes as they occur. Since the attitude or inclination angle of the vehicle changes relatively slowly compared to the dynamic frequency response of the accelerometer, the accelerometer  40  output is filtered to remove high frequency noise. 
     The accelerometer  40  is oriented so that when the vehicle is tilted to one side, a static, fully tipped over position (90°) is sensed as −1 (g) lateral force with a voltage output at a minimum level, such as about 0.833 volts. When tipped to the other side, the tipped over position is sensed at +1 (g) lateral force with a voltage output at a maximum level, such as about 4.167 volts. Based on the voltage levels given in the example above, the accelerometer  40  has a sensitivity of 1.167 volts/g. 
     The actual static accelerometer voltage produced by the accelerometer  40  deviates from ideal values due to manufacturing tolerances, assembly tolerances, and temperature changes. The actual voltage sensitivity is determined by the following formula: 
     
       
           V   sens   =[V   out (+1 g)− V   out (−1 g)]/2 
       
     
     The actual static upright position is determined according to the formula: 
     
       
           V   out(upright)   =[V   out (+1 g) −V   out (−1 g)]/2 
       
     
     The actual static vertical component of gravity, in g&#39;s, is determined according to the formula: 
     
       
           g&#39;s= ( V   out(lean)   −V   out(upright) )/ V   sens   
       
     
     The actual static vehicle inclination angle, in degrees is determined according to the following formula: 
     
       
         ANGLE deg =cos −1 ( ABS ( g&#39;s )) 
       
     
     The voltage output of the accelerometer  40  may be used to determine when the vehicle has begun and completed a turn. As should be evident from the discussion above, when the vehicle begins a turn, lateral forces act upon the accelerometer causing it to generate an output of a predetermined amount. As the vehicle turns back to an upright position at the end of the turn, lateral forces act upon the accelerometer causing it to generate another output of another predetermined amount. If the outputs, which are preferably digital and measured in A/D counts, occur over a certain period of time, the movement is considered to be a turn by the processor  12 . Determination of turn completion is discussed in greater detail below. 
     In addition to the input from the accelerometer  40 , in an optional embodiment of the present invention, the processor  12  also receives input from a receiver  42 . The receiver  42  is tuned to receive messages from a transmitter  44 . As will be discussed in greater detail below, the receiver  42  and transmitter  44  are part of a security sub-system of the system  10 . 
     As noted, the processor  12  controls activation of various vehicle systems. The processor  12  includes a turn-signal controller (implemented as software) that controls a set of left turn signal lamps  50  and a left turn indicator  51  through line LT_LAMP. The turn-signal controller also controls a set of right turn signal lamps  52  and a right turn indicator  53  through the line RT_LAMP. The sets of turn signal lamps  50  and  52  are turned on when a rider activates the left turn signal switch  30  or right turn signal switch  32 , as the case may be. The rider may manually shut off the left turn signal lamps  50  by activating the left turn signal switch  30  again, while the lamps are on. The right signal lamps may be shut off in a similar fashion. 
     A flasher  54 , which includes a current sensor  56 , drives the sets of turn signal lamps  50  and  52 . The current sensor  56  generates a status output that is delivered to the processor  12  on the line STATUS. The status output represents the flashing or flash rate of the activated set of lamps. 
     The processor  12  provides automatic shut off of the sets of turn signal lamps  50  and  52  through the turn-signal controller. The turn-signal controller is activated when an input signal on the LT_SW or RT_SW lines is present for a minimum period of time, such as 70 ms. When this occurs, the turn-signal controller counts the number of flashes of the activated set of lamps and automatically cancels or turns off the activated lamps after a certain number of flashes. In the embodiment shown, shut off occurs after 20 flashes, which is equal to approximately 12 seconds. 
     The basic turn signal cancellation based on time may be enhanced by accounting for changes in vehicle motion (i.e., speed and acceleration). The turn-signal controller initiates a speed-based, extended counting shut off when the absolute vehicle speed reaches a certain value or a certain change in vehicle speed occurs. The turn-signal controller receives vehicle speed information either from the BUS or VSS lines as described above, and calculates acceleration based on the difference in vehicle speed in successive speed measurements. The turn-signal controller suspends counting of flashes when the vehicle speed is less than or equal to a low speed threshold value, such as 5 mph. The turn-signal controller also suspends counting flashes when the vehicle deceleration is greater than or equal to a deceleration threshold value, such as 1 mph/sec. 
     Turn signal cancellation may also be accomplished based on changes in lateral forces that occur during vehicle maneuvering. The turn-signal controller constantly monitors the lateral force acting on the vehicle to determine when a turn has been started. The start of a turn is indicated by an absolute difference between the sensed lateral force and the output of the accelerometer when the vehicle is moving in a straight direction, such as 2 A/D counts (the “turn bank angle”) for a certain amount of time, such as about 300 ms (the “turn bank time”). The completion of a turn is indicated by an absolute difference between the sensed bank angle and the current upright position of less than a certain predetermined amount, such as 2 A/D counts (the “turn upright angle”), for a certain period of time, such as about 500 ms (the “turn upright time”). The flash sequence of the activated lamps is terminated by the turn-signal controller a predetermined number of flashes (e.g., 2) after the turn is determined to be complete. 
     Turn signal cancellation based on changes in lateral force is suspended based on the speed and deceleration criteria discussed above. Specifically, cancellation of flashing may be suspended or disabled if the vehicle speed is less than a low speed threshold value, such as 6 mph. Cancellation of flashing may also be suspended if the vehicle deceleration is greater than or equal to a deceleration threshold value such as 1 mph/sec. 
     Turn signal cancellation based on changes in lateral forces must be modified if a sidecar is installed on the motorcycle having the system  10 . When a sidecar is installed, the turn bank angle and turn bank time are increased. Specifically, they are adjusted to 10 A/D counts and about 800 ms, respectively. Modification of turn signal cancellation according to speed or acceleration, as discussed above, may be applied to sidecar installations, if desired. The processor  12  knows whether a side car is installed on the vehicle based on input from one of the turn signal lines received during a program mode (discussed below). In the embodiment described herein, the commands from the left turn signal line LT_SW indicate whether a sidecar is installed. The first transition of the left turn signal switch from the active to the inactive state is interpreted as an indication that no sidecar is installed. The next transition indicates that a sidecar is installed. A transition past two causes the pattern to repeat. 
     Another useful control function provided by the processor  12  is four-way flashing. If the processor is in the IGN/STOP or IGN/RUN mode, it will activate the turn signal lamps  50  and  52  when both the left turn signal switch  30  and the turn signal switch  32  are activated again simultaneously for a minimum period of time, such as 0.2 seconds. The processor  12  activates the lamps  50  and  52  for a flashing period, such as 120 minutes, or until both of the turn signal switches  30  and  32  are again activated simultaneously for the minimum period of time. 
     The turn signal lamps  50  and  52  are also used to provide indications of system diagnostics for short circuit to battery, short circuit to ground, or open circuit conditions. The processor  12  periodically conducts diagnostic testing on these and other conditions such as battery overcharge. For example, to test for a short circuit to battery condition, the processor  12  checks output feedback signals, such as the IGN_ENABLE_FB, to determine if a short has occurred. A short has occurred if the output feedback is high, the corresponding output signal is high, and the battery voltage is in a specified operating range, such as 9.0 volts to 15.0 volts. If a short is detected, turn signal lamps  50  and  52  are flashed. The turn signal lamps  50  and  52  are also flashed if a short circuit to ground condition is detected by the processor  12 . 
     Testing for open circuit conditions in the turn signal lamps  50  and  52  is performed by the processor  12  each time the power mode transitions from OFF to IGN/RUN or IGN/STOP. The processor individually activates the LT_LAMP and RT_LAMP lines for an open-lamp-on time, such as about 200 ms. The processor  12  measures the lamp currents during the last portion of the open-lamp-on time (e.g., the last 25% of the open-lamp-on time). If the left and right turn signal lamp currents do not agree within a threshold amount (e.g., 30%), the processor  12  determines that an open circuit condition exists for the side with the lower current. Once an open circuit condition is detected, the lamps  50  and  52  are flashed at a high rate, such as twice the normal flashing rate, until the flashing is manually cancelled. 
     In addition to controlling the sets of turn signal lamps  50  and  52 , the processor  12  controls a starter  60  through a STARTER line. In motorcycles lacking a network bus, the processor may also be configured to control the ignition module  20  through the IGN_ENABLE line. Control of the starter  60  and ignition module  20  (as required) is administered by a tip-over module or controller in the processor  12 . The tip-over controller (preferably implemented in software) monitors the output of the accelerometer and determines whether a tip-over condition exists. For the example described herein, a tip-over condition exists if the static lean angle of the vehicle is at about 45 degrees or more (tip angle) for a period of about 700 ms (tip-over time). If a tip-over condition exists, the tip-over controller shuts off the engine by sending an engine disable message over the BUS (for bus-equipped vehicles) to the ECM  20 A or by deactivating the IGN_ENABLE output to the ignition module  20  (for non-bus enabled vehicles). 
     Simultaneous with the engine shut down, the tip-over controller deactivates the LT_LAMP and RT_LAMP lines and any active outputs over the STARTER line. Once these disabling commands have been executed, the tip-over controller remains in a tip-over condition until the power mode transitions from OFF to IGN/STOP or IGN/RUN. The tip-over controller is disabled if a sidecar is installed on the motorcycle. 
     As noted above, the system  10  may include a security sub system. The security sub system includes a security controller (preferably implemented as software) installed on the processor  12 . When the system  10  includes a security sub system, the processor  12  generates a command signal in response to various alarm conditions (discussed below). The command signal causes the generation of visual, audio, and other alarm indicators. In one form of the invention, the sets of turn signal lamps  50  and  52  are flashed when an alarm condition exists. Optionally, the processor may be coupled to additional alarm devices such as a pager  70 , a battery backed siren  72 , a standard siren  74 , or a combination of these items. Commands from the processor  12  are delivered to these devices along an ALARM line. 
     In the preferred embodiment of the system  10 , the security controller of the processor  12  is disabled until one or more transmitters  44  have been assigned to the receiver  42 . Once the transmitter  44  has been assigned to the receiver  42 , the security controller is activated (or armed) and deactivated (or disarmed) by command signals received from the transmitter  44 . Optionally, the security controller may be designed to self-arm after a predetermined period of time (such as 30 seconds) when the system  10  enters the OFF power mode, such as occurs after the engine is shut off. This is known as passive arming. 
     Regardless of how the security controller is activated, once armed the security controller monitors the vehicle for disturbances indicative of tampering. These disturbances are also referred to herein as alarm conditions. The monitored alarm conditions include vehicle motion, tampering of the IGN input, tampering of the IGN_ENABLE_FB input, tampering of the AUX_I/O input, detection of a non-security telltale message on the BUS, and detection of a battery connect or reconnect. If one or more of these conditions are detected, alarm commands are delivered to the sets of signal lamps  50  and  52  and any optional alarm devices installed on the vehicle. One interesting feature of the security controller is that it does not interfere with the turn signal controller&#39;s ability to operate the turn signal lamps in a four-way flashing mode. Thus, it is possible to arm the security controller and leave the turn signal lamps flashing, when the ignition key is removed and the ignition switch  16  is locked. Leaving the motorcycle  11  in this condition may be desirable during a roadside break down. 
     The security controller also controls a security telltale that is operable to visually alert a rider as to the state (armed or disarmed) of the security controller. For example, the telltale may take the form of an LED  76  that receives commands from the processor  12  along a SECURITY_LED line. 
     The overall operation of the security controller is best understood by reference to FIG. 4 which illustrates the operation of the security controller in terms of operating states and modes. The security controller has two states: armed and disarmed. In the disarmed state, of course, the security controller does not monitor the vehicle for alarm conditions. As noted above, when the security controller is armed, it monitors the vehicle for alarm conditions. The security controller also immobilizes the vehicle when it is in the armed mode. In particular, the security controller drives the STARTER line high to disable the starter relay. The security controller also deactivates the engine controller when in the armed state. For bus-equipped vehicles, the security controller delivers a signal over the bus line to ECM  20 A to disable engine operation. For non-bus-equipped vehicles the IGN_ENABLE output is driven high to deactivate the ignition module  20 . 
     Specific operations carried out by the security controller are best understood by examining the controller&#39;s modes of operation, which include a standby mode  80 , an ignition-on mode  82 , a passive delay mode  84 , an armed mode  86 , a warning mode  88 , an alarm mode  90 , a rearm delay mode  92 , and a personal code security mode  94 . 
     In the standby mode  80 , the security controller is disarmed and the vehicle is in the OFF power mode. The security telltale is inactive, any audible alarm is inactive, any visual alarm is inactive, the IGN_ENABLE line is inactive, and the STARTER line is inactive. The security controller remains in the standby mode  80  until one of the conditions in Table B is met. 
     
       
         
               
               
             
           
               
                 TABLE B 
               
               
                   
               
             
             
               
                 a 
                 The power mode transitions to either IGN/STOP or IGN/RUN. In 
               
               
                   
                 this case, the security controller enters the ignition-on security mode 
               
               
                   
                 82. 
               
               
                 b. 
                 The power mode remains in an OFF status when the passive arming 
               
               
                   
                 option is selected. When this occurs, the security controller enters 
               
               
                   
                 the passive delay security mode 84. 
               
               
                 c. 
                 A valid remote arm command is received from the transmitter 44. In 
               
               
                   
                 this case, the security controller enters the armed mode 86. 
               
               
                 d. 
                 The security controller receives a vehicle security trigger alarm 
               
               
                   
                 through the BUS. In this case, the security controller enters the 
               
               
                   
                 alarm mode 90. 
               
               
                   
               
             
          
         
       
     
     In the ignition-on security mode  82 , the security controller is disarmed and the vehicle is in the IGN/STOP or IGN/RUN power mode. In the ignition-on security mode  82 , the security telltale is active for a certain period of time to ensure that the LED  76  or other light emitting device is operable. Any audible alarm is inactive, any visual alarm is inactive, the IGN-ENABLE line is active, and the STARTER line is also active. The security controller remains in the ignition-on mode  82  until one of the conditions in Table C is met. 
     
       
         
               
               
             
           
               
                 TABLE C 
               
               
                   
               
             
             
               
                 a. 
                 The power mode transitions to OFF. In this case the security function 
               
               
                   
                 enters the standby mode 80. 
               
               
                 b. 
                 The security controller receives a vehicle security trigger alarm 
               
               
                   
                 message. In this case the security function enters the alarm mode 86. 
               
               
                   
               
             
          
         
       
     
     In the passive delay mode  84 , the security controller waits for the passive arming delay time to expire (when the security controller is designed with the passive arming feature). In this mode, the security telltale is active, any audible alarm is inactive, any visual alarm is inactive, the IGN_ENABLE line is inactive, and the starter enable is inactive. The security controller remains in the passive delay mode  84  until one of the conditions in Table D is met. 
     
       
         
               
               
             
           
               
                 TABLE D 
               
               
                   
               
             
             
               
                 a. 
                 The power mode transitions to either IGN/STOP or IGN/RUN. In 
               
               
                   
                 this case the security controller enters the ignition-on mode 82. 
               
               
                 b. 
                 A valid remote armed command is received from the transmitter 44. 
               
               
                   
                 In this case, the security controller enters the armed mode 86. 
               
               
                 c. 
                 The security controller remains in the passive delay mode 84 for 
               
               
                   
                 greater than a predetermined delay time (such as 30 seconds). In 
               
               
                   
                 this case, the security controller enters the armed mode 86. 
               
               
                   
               
             
          
         
       
     
     In addition to the conditions listed on Table C, the security controller will exit the passive delay mode if it receives a vehicle security trigger alarm message over the BUS. If that occurs, the security controller enters the alarm mode  90 . 
     In the armed mode  86 , the security controller is armed and monitoring the vehicle for tampering (i.e., alarm conditions). When in the armed mode  86 , the security telltale is cycled for one quick flash, the audible alarm is chirped, the visual alarm flashes a predetermined number of times, the IGN_ENABLE line is inactive, and the STARTER line is inactive. The security controller remains in the armed mode  86  until one of the conditions in Table E is met. 
     
       
         
               
               
             
           
               
                 TABLE E 
               
               
                   
               
             
             
               
                 a. 
                 The vehicle inclination angle departs from the initial armed 
               
               
                   
                 inclination angle by more than about 10 counts. In this case, the 
               
               
                   
                 security controller enters the alarm mode 90. 
               
               
                 b. 
                 The vehicle inclination angle departs from the initial armed 
               
               
                   
                 inclination angle by more than about 2 counts. In this case, the 
               
               
                   
                 security controller enters the warning mode 88. 
               
               
                 c. 
                 The IGN input becomes active. In this case, the security controller 
               
               
                   
                 enters the alarm mode 90. 
               
               
                 d. 
                 The IGN_ENABLE_FB line becomes active. In this case, the 
               
               
                   
                 security controller enters the alarm mode 90. 
               
               
                 e. 
                 The AUX_I/O input becomes active. In this case, the security 
               
               
                   
                 controller enters the alarm mode 90. 
               
               
                 f. 
                 A non-security telltale message is received on the BUS. In this case, 
               
               
                   
                 the security controller enters the alarm mode 90. 
               
               
                 g. 
                 A battery connect or reconnect is detected. In this case, the security 
               
               
                   
                 controller enters the alarm mode 90. 
               
               
                 h. 
                 The security controller receives a vehicle controller trigger alarm 
               
               
                   
                 message over the BUS. In this case, the security controller enters the 
               
               
                   
                 alarm mode 90. 
               
               
                 i. 
                 A valid remote disarm command is received from the transmitter 44. 
               
               
                   
                 In this case, the security controller enters the standby mode 80. 
               
               
                   
               
             
          
         
       
     
     In the warning mode  88 , the security controller detects a disturbance of the vehicle which is assumed to have been caused by a potential thief and attempts to warn the potential thief prior to setting off the full alarm. When the security controller is in the warning mode  88 , the security telltale is active, the visual alarm is active, the IGN_ENABLE line is inactive, and the STARTER line is inactive. The security controller remains in the warning mode  88  until one of the conditions in Table F is met. 
     
       
         
               
               
             
           
               
                 TABLE F 
               
               
                   
               
             
             
               
                 a. 
                 The vehicle inclination angle returns within about 2 counts of the 
               
               
                   
                 initial armed inclination angle in less than a predetermined period 
               
               
                   
                 of time, such as three (3) seconds. In this case, the security controller 
               
               
                   
                 immediately cancels the alarm and enters the armed mode 86. 
               
               
                 b. 
                 The vehicle remains at an inclination angle from the initial armed 
               
               
                   
                 inclination angle for a predetermined period, such as three (3) 
               
               
                   
                 seconds. In this case, the security controller enters the alarm 
               
               
                   
                 mode 90. 
               
               
                 c. 
                 The vehicle inclination angle departs from the initial armed angle by 
               
               
                   
                 more than about 10 counts. In this case, the security function enters 
               
               
                   
                 the alarm mode 90. 
               
               
                 d. 
                 The IGN input becomes active. In this case, the security controller 
               
               
                   
                 enters the alarm mode 90. 
               
               
                 e. 
                 The IGN_ENABLE_FB line becomes active. In this case, the 
               
               
                   
                 security controller enters the alarm mode 90. 
               
               
                 f. 
                 The AUX_I/O input becomes active, causing the security controller 
               
               
                   
                 to enter the alarm mode 90. 
               
               
                 g. 
                 A non-security telltale message is received on the BUS. In this case, 
               
               
                   
                 the security controller enters the alarm mode 90. 
               
               
                 h. 
                 A battery connect or reconnect is detected, causing the security 
               
               
                   
                 controller to enter the alarm mode 90. 
               
               
                 i. 
                 A valid remote arm command is received from the transmitter 44. In 
               
               
                   
                 this case, the security controller cancels the alarm and enters the 
               
               
                   
                 armed mode 86. 
               
               
                 j. 
                 A valid remote disarm command is received from the transmitter 44. 
               
               
                   
                 In this case, the security controller cancels the alarm and enters the 
               
               
                   
                 standby mode 80. 
               
               
                   
               
             
          
         
       
     
     In the alarm mode  90 , the security controller has detected alarm conditions that set off alarms coupled to the processor  12 . In this mode, the security telltale is active, the audible alarm is active, the visual alarm is active, the IGN_ENABLE line is inactive, and the STARTER line is inactive. The security controller remains in the alarm mode  90  until one of the conditions in Table G is met. 
     
       
         
               
               
             
           
               
                 TABLE G 
               
               
                   
               
             
             
               
                 a. 
                 The security controller remains in the alarm mode for greater than a 
               
               
                   
                 predetermined period of time such as 30 seconds. In this case, the 
               
               
                   
                 security function enters the rearm delay mode 92. 
               
               
                 b. 
                 A valid remote arm command is received. In this case, the security 
               
               
                   
                 function immediately cancels the alarm and enters the armed mode 
               
               
                   
                 86. 
               
               
                 c. 
                 A valid remote disarm command is received. In this case, the 
               
               
                   
                 security controller cancels the alarm and enters the standby mode 80. 
               
               
                   
               
             
          
         
       
     
     In the rearm delay mode  92 , the security controller determines whether alarm conditions are continuous in order to prevent nuisance alarms from occurring. In this way, if an alarm condition ceases to exist, the audible and visual alarms are deactivated. When in the rearm delay mode  92 , the security telltale is active, the audible alarm is active, the visual alarm is inactive, the IGN—ENABLE line is inactive, and the STARTER line is inactive. The security controller remains in the rearm delay mode  92  until one of the conditions in Table H is met. 
     
       
         
               
               
             
           
               
                 TABLE H 
               
               
                   
               
             
             
               
                 a. 
                 The previous alarm mode 90 was entered as a result of vehicle motion 
               
               
                   
                 and additional motion has occurred since the security controller was 
               
               
                   
                 last disarmed. When this occurs, the security controller ignores 
               
               
                   
                 additional changes in inclination until the security controller is 
               
               
                   
                 disarmed and then rearmed. 
               
               
                 b. 
                 The previous alarm mode 90 was entered as a result of an IGN input 
               
               
                   
                 tampering and the LT_SW and RT_SW inputs were active during 
               
               
                   
                 the alarm delay time. In this case, the security controller enters the 
               
               
                   
                 personal code security mode 94. 
               
               
                 c. 
                 The previous alarm mode 90 was entered as a result of IGN input 
               
               
                   
                 tampering and ten violations have occurred since the security 
               
               
                   
                 controller was last disarmed. The security controller ignores 
               
               
                   
                 additional IGN input tampering until the security controller is 
               
               
                   
                 disarmed and then rearmed. The security controller exits the rearm 
               
               
                   
                 delay mode 90 for similar situations involving the IGN_ENABLE 
               
               
                   
                 tampering and AUX_I/O tampering. The security controller operates 
               
               
                   
                 in a similar manner for non-security telltale messages and battery 
               
               
                   
                 connect/reconnect tampering. 
               
               
                 d. 
                 The security controller remains in the rearm delay mode for a time 
               
               
                   
                 greater than a predetermined period, such as ten (10) seconds. In this 
               
               
                   
                 case, the security controller enters the armed mode 86. 
               
               
                 e. 
                 The security controller receives a vehicle security intruder alarm 
               
               
                   
                 message. In this case, the security controller enters the alarm mode 
               
               
                   
                 90. 
               
               
                 f. 
                 A valid remote arm command is received from the transmitter. In this 
               
               
                   
                 case, the security controller enters the armed mode 86. 
               
               
                 g. 
                 A valid remote disarm command is received. In this case, the security 
               
               
                   
                 controller enters the standby mode 80. 
               
               
                   
               
             
          
         
       
     
     As noted above, the security controller receives commands from transmitter  44  through the receiver  42 . However, the security controller may operate in the personal code security mode  94  where the rider may input codes through the left and right turn signals switches  30  and  32 . The personal code security mode allows a rider to disarm the security controller without a valid transmitter. In the personal code security mode  94 , the security telltale is active, the audible alarm is inactive, the visual alarm is inactive, the IGN—ENABLE is inactive and the STARTER enable is inactive. The security controller remains in the personal code security mode  94  until an appropriate disarming procedure is successfully completed, in which case the security controller enters the standby mode  80 . If the disarming procedure is not successfully completed, the security controller enters the alarm mode  90 . If a valid remote arm or disarm command is received, the security controller enters the armed mode  86  or the standby mode  80 , as the case may be. 
     To successfully disarm the security controller in the personal code security mode  94 , the rider enters a personal code containing a predetermined number of digits. The personal code must have been previously programmed into the system, as will be described further herein. To enter the personal code security mode  94 , the rider must move the ignition switch  16  to the ignition position I and then immediately to the accessory position A. This causes the security controller to enter the alarm mode  90 . The rider then simultaneously activates the left and right turn signal switches  30  and  32 , which causes the security controller to enter the personal code security mode  94 . In this mode, the security controller flashes the security telltale and monitors the LT_SW and RT_SW lines. If no activity is detected for a timeout period, such as 30 seconds, the security controller returns to the alarm mode  90 . If input is detected, the security controller determines whether that input matches the previously stored code. 
     The security controller is designed such that toggle inputs from the left turn signal switch  30  represent the digits of the personal code. Single toggle inputs from the right turn signal switch  32  are used to inform the security controller to process the toggle inputs from the left turn signal switch  30  as a digit. For example, to enter the code “321,” the left turn signal switch  30  is depressed three times, then the right turn signal switch  32  is depressed once. The left turn signal switch  30  is then depressed two times, and the right turn signal switch  32  is depressed once. Finally, the left turn signal switch  30  is depressed once, and the right turn signal switch  32  is depressed once. If the proper code is entered, the security controller disarms the system and flashes the left and right turn signal lamps  50  and  52  for a security flash time, such as 100 ms. 
     As described, many of the features of the system  10  are dependent upon preprogrammed information input to the processor  12  during a programming mode. Before the processor may be placed in the programming mode, the security controller must be disarmed and the run/stop switch  18  must be in the stop position. Provided these conditions exist, the mode is entered following appropriate cycling of the ignition switch  16  and turn signal switches. In the embodiment described herein, cycling must occur according to the steps in Table I. 
     
       
         
               
               
             
           
               
                 TABLE I 
               
               
                   
               
               
                 Step 
                   
               
               
                 No. 
                 Action 
               
               
                   
               
             
             
               
                 1 
                 Turn ignition switch from OFF to IGN 
               
               
                 2 
                 Cycle the ignition switch from IGN to OFF to IGN 
               
               
                 3 
                 Cycle the ignition switch again from IGN to OFF to IGN 
               
               
                 4 
                 Toggle the left turn signal switch from OFF to ON to OFF 
               
               
                 5 
                 Toggle the left turn signal switch again from OFF to ON to OFF. 
               
               
                   
               
             
          
         
       
     
     Once in the programming mode, the processor does not perform any of its other defined functions. The processor  12  remains in the programming mode until the ignition switch is turned to the OFF position. 
     While in the programming mode, a rider may customize the operation of certain features of the system  10 . As noted above, the programming mode provides a mechanism for informing the processor  12  of the rider&#39;s personal code and whether a sidecar is installed on the vehicle. Other customizations may be accomplished through the programming mode, including modification of the alarm sensitivity, sign-up of the transmitter  44 , the type of visual alarm provided by the system  10  (for example, a single, a double, or triple flashing), and the passive arming feature. Specifically, in the embodiment shown herein, features are customized using three groups: base level, security and immobilization, and personal code entry and verification. In the base level group, the RF transmitter sign-up, sidecar and service diagnostic features may be modified. In the security and immobilization group, tamper alarm sensitivity and passive arming may be modified. In the personal code entry and verification group, the personal code may be modified. Each feature may have an option. For example, the sidecar feature may have an “installed” option or a “not installed” option. The other features described above have similar options, which for the sake of brevity are not explained herein. 
     The processor  12  provides feedback to the rider to indicate the current customization groups, features, and options selected. This feedback consists of a number of turn signal flashes equal to the particular group, feature, or option. Customization of the system  10  is accomplished by selecting a customization group by activating one of the valid group control inputs. The activation of a control group input causes the processor to select a customization group associated with that input. Each time a new customization group is selected, the current feature selected is shown using the feedback described above. The next time a group control input is activated the next feature in that group is selected by the processor  12 . If the processor  12  is in a particular customization group and detects a transition on the group control input for a different customization group, the processor transfers control to the new customization group after first storing the old customization group current settings. Generally, customization groups are selected using the right turn signal switch  32  and features within customization groups are selected using the left turn signal switch  30 . The first time the left turn signal switch  30  is toggled for a newly selected feature, the current option is shown using the feedback described above. The next time the turn signal switch is toggled the next option is selected. The processor  12  stores the current settings for all customization groups in nonvolatile memory prior to exiting the programming mode. 
     As noted above, the security controller may control a battery backed siren  72 . If implemented, it is preferred that the battery backed siren  72  take the form shown in FIG.  5 . 
     As shown in FIG. 5, the battery backed siren  72  includes an internal battery  110 , a siren module  112 , and an audio device  114 , such as a piezo-electric loudspeaker. The siren module  112  is powered by the battery  14  over a battery line  116 . The siren module  112  uses power from the line  116  to recharge the internal battery  110 , when the module is operating in a standby mode, and when the audio device  114  is activated by an input received over the ALARM line. 
     The siren module  112  may be in one of two states: an armed state and a disarmed state. The siren module  112  enters the armed state if a proper digital code or pulse sequence of a predetermined number of pulses is received over the ALARM line while the battery and ground connections to the vehicle are intact. If the number of pulses received is outside a specified or predetermined range, the siren module  112  retains its prior status. If the siren module  112  receives an appropriate pulse train, it produces an indication to verify that it has entered an armed state and provide a notification as to the status of the internal battery  110 . Preferably, the siren module  112  produces two chirps when it has received an appropriate pulse train and the internal battery is installed. The siren module  112  produces three chirps when it has received an appropriate pulse train, but the internal battery has not been installed. 
     The siren module  112  is disarmed when it receives an appropriate pulse sequence such as ten pulses over the ALARM line while the battery and ground connections to the vehicle are intact. If an inappropriate pulse train is received, the siren module  112  remains in its previous status. 
     While in the armed state, the siren module  112  monitors all three input lines: the battery line  116 , the ALARM line, and the ground input GND. In the armed state, the alarm device  114  is activated when the ALARM line input is held low for a period greater than a predetermined amount of time, such as 50 milliseconds. The siren module  112  deactivates the audio device  114  if the ALARM line signal is driven high by the security controller or the ALARM line signal is held low for longer than a predetermined time, such as 30 seconds. 
     One useful aspect of the battery backed siren  72  is that it self-activates the audio device  114  if a failure condition (which may indicate tampering) exists. For example, disconnection of the battery line  116 , the ALARM line, or the ground line GND causes the siren module  112  to activate the audio device  114  in a cyclical manner for a predetermined amount of time. For example, the audio device  114  may be driven for 25 seconds followed by a 5 second interval of silence for a total of ten cycles. 
     As can be seen from the above, the present invention provides an integrated security, tip-over, and turn signal system that uses a single processor and has reduced wiring requirements, improved reliability, and enhanced features for rider safety and convenience. While various details and examples have been used to explain the invention, it is to be understood that the invention is not limited in its application to the description or illustration set forth herein. Rather, it is recognized that modifications may be made by one of ordinary skill in the art of the invention without departing from the spirit or intent of the invention and, therefore, the invention is to be taken as including all reasonable equivalents of the subject matter of the appended claims.