Note: Descriptions are shown in the official language in which they were submitted.
2133673 INTRODUCTION AND DESCRIPTION OF THE PRIOR ART The present invention is addressed to the problem of emergency signal transmission from remote vehicles, and expected to have greatest use in single-driver vehicles such as taxi-cabs, although it can be of use in other single- or multiple-occupant vehicles. More specifically, it is addressed to such signal transmission when relayed by satellite, so that the drawbacks of cellular tMn~mis~ion are overcome. The problem of emergency situations in vehicles which range freely over a large area has always been great; whether this means the innuit boy on the stalled snowmobile who froze to death half a day's walk from his home village, or the taxi-driver who doesn't return after shift, the problem is the same: where is he/she? why so late? is something wrong? The advent of radio communications has greatly improved the situation, so that now if appl~pliate equipment has been installed--such as a two-way radio--a call for help can be made. With the advent of the GPS (Global Positioning by Satellite) even more improvements have been made, since the driver does not need to know or be able to describe the location: they may be lost, but the GPS will still know where they are. Many systems using GPS have been described in previous patents and commercial releases; a simple example is U.S. patent #5,043,736 ~Darnell et al, 1991), which specifies a hand-held remote unit that receives GPS data and sends it via a cellular system to a base computer. A more complex discussion of GPS is given in U.S patent #5,223,84~ (Manseli et al, 1993); but the information flow is much the same. However there are still drawbacks to the use of commercially-available GPS monitoring systems in specialized situations. The main one is that existing cellular phone systems are extremely limi~e~l The vehicle needs to be within 30 km of a cellular relay tower; and in some parts of the world, such as the United States, cellular areas are m~int~in~ by separate companies and travelling into a neighboring area may result in interruption of service. Since by definition an emergency system is something that must ~ 2133673 always work, this is a serious drawback. The present invention will overcome this by using a satellite relay between the vehicle and its base coll~puler. Specifically, the MSATTM (Mobile SATellite link) owned by Telesat MobileTM Inc., to be l~lm~h~l in 1995, will provide commercially available data relay through its Packet DataTM service. In combination with this satellite, or with others that will likely be launched in future, the present invention will provide vehicles anywhere in North America, and eventually the world, with superior emergency signal tr~nsmi~sion. The described embodiment of the invention will be that fashioned for taxi- driver use, and so will incorporate secreted driver-activated alarm triggers (for dangerous situations). Also because low cost is a consideration for most taxi-drivers (and many other users) the described embodiment will be that having an optional tr~nsmi~ion using cellular or radio commllnications; thus if the early commercial costs charged for s~tçllite use are high, the unit will automatically use cellular or radio unless these are unavailable; it will then switch to satellite. Also because of use in dangerous situations (such as criminal assault) the alarm will continue to transmit position data unless deactivated from the base comp.ller, again via the satellite where necessary. An object of the present invention is to provide for a vehicle emergency signal tr~n~mi~ion system comprising the elements of: vehicle positioning data means; vehicle computer means; alarm means; satellite transceiver means; relay satellite means; and base computer means. In this invention the position of a vehicle is transmitted to the base computer means in an emergency situation by the following steps: (a) vehicle position data is continuously provided to the vehicle computer means by the vehicle positioning data means; (b) an alarm is signaled to the vehicle computer means by the alarm means; (c) the vehicle computer means provides continuous vehicle position data and the alarm signal to the base computer means through the satellite transceiver means and the relay satellite means; and 2133673 (d) the base computer means deactivates the alarm means by sign~lling the vehicle computer means through the relay satellite means and the satellite transceiver means. It is also an object to provide for an invention disclosing a vehicle emergency signal tr~nsmi~ion system comprising the elements of: GPS means, comprising the RockwellTM International MicroTrackerTM (RockwellTM part #TU-D150-041) module and GPS antenna; vehicle computer means comprising: system data bus; serial in/out ports; system controller using the IntelTM TS80C188EB microprocessor in the 80 pin PQFPpackage as a system processor; volatile memory; static memory; real time clock chip with watchdog timer; and expansion bus, comprising a connector and ~pprop-iate logic to support an IntelTM AP-96 iSBX expansion bus; alarm means comprising: alarm button in the vehicle driver's compartment and alarm button in the vehicle trunk; three alarm interrupt interfaces in the system controller, two of which are connected to the alarm buttons and one of which is addressed through a serial port; cellular modem means comprising a custom HayesTM AT command-set compatible 2400 BAUD module and a cellular ~ntenn~; satellite transceiver means comprising: an MSATTMPacket DataTM compatible satellite transceiver card sending at between 1626.5 and 1660.5 MHz and receiving at a frequency range between 1525 and 1559 MHz; and a satellite ~ntenn~; MSATTM relay s~tellit~; and base compulel, wherein an emergency signal is transmitted by means of the following steps: (a) vehicle GPS data is obtained by the MicroTrackerTM module through the GPS antenna on a continuous basis, and a fix is stored in Nonvolatile RAM in the real time clock and updated once a second. (b) one of the three alarm interrupt interfaces in the system controller is ~ ` 213367~ addressed by an alarm signal generated from the group cont~ining- driver-activated by a button in the driver' s compartment; driver-activated by a button in the trunk; automatically activated by time travelled; automatically activated by distance travelled; activated by the base computer by means of a serial in/out port in the vehicle computer. (c) The system controller registers the alarm. (d) The system controller obtains current GPS fix if available; if unavailable due to bridge, tunnel, or structural shielding it obtains the fix stored in memory. (e) The system controller sends the GPS fix and alarm to the cellular modem module, if within range of a cellular tower; or to the satellite transceiver module if not. (f) Either the cellular modem module or satellite transceiver module sends the alarm and GPS fix, via the appl~,pliate ~ntenn~, to the base computer; and does so continuously, with new GPS fix when available. (g) When the situation has been understood or resolved, but not until, the base station co~ uler sends a coded deactivation message to the vehicle to stop transmitting data. (h) Optionally, at any time the base station computer sends a break-in message to the vehicle computer and obtains current GPS fix. (1~ Optionally, further instructions, including software, are sent to the vehicle computer from the base station computer, so that the vehicle computer transmits GPS fixes at instructed times, distances, or in instructed formats. (J) Optionally, the vehicle computer is customized and expanded by means of plugged-in hardware and software, accommodated by the on-board IntelTM AP-96 iSBX expansion bus. In such a system all physical components of the system that are in the vehicle, except the antennae and alarm buttons, may be together in a single protective housing ~pprupliate to withstand extreme conditions found in a vehicle, such as extremes of humidity, telllpel~lule, vibration, magnetic fields, and power supply variation; these ~ 2133673 portions in the housing being the GPS receiver module; vehicle computer; alarm means excluding the alarm buttons; cellular modem module; and s~tellite transceiver module. DETAILED DESCRIPI ION OF THE INVENTION For this description, refer to the following diagrams, wherein like numerals refer to like parts: Figure lA, a block flow diagram of an embodiment of the invented system; Figure lB, a block flow diagram of an alternative embodiment of the invented system; Figure lC, a block flow diagram of another alternative embodiment of the invented system; and Figure 2, a block diagram of the vehicle data bus and attached hardware and processors, of the embodiment illustrated in Figure lC. An overview flow diagram of the invented vehicle emergency signal transmission system is generally indicated as 10 in Figure lA. Vehicle position data 11 is passed to the remote vehicle computer 12 on a continuous basis. When an alarm 13 has been signaled, for instance from a driver panic button (not shown on Figure lA), the vehicle position data 11 and existence of the alarm signal 13 are passed from the remote vehicle computer 12 to the relay satellite send and receive 14, relay satellite 16, and thereby to the base coll-y.llel 18. This is a preferred future embodiment; however with the expected initial high cost of satellite connections, a more cost-effective initial route will be followed. One is shown in Figure lB, where an alternative emergency data tran~mi~ion system 20 is shown that gives a choice of radio 24a, cellular 24b, or satellite 24c ~rancmi~ion. In most cases in the embodiment shown in Figure lB (and Figure lC, a variant) either vehicle computer 22 or base computer 26, or a combination, will make the decision as to which transmit and receive mode to use. This decision could also be made 2133673 by a vehicle driver input into the vehicle computer 22, although this input is not shown on the Figures. It will be understood also that the other two combinations, such asemergency transmit system generally indicated as`30 in Figure lC having the choice between cellular 34a and s~tellite 34b (i.e., no radio), or between a satellite and a radio (i.e., no cellular) (this possibility is not diagrammed) will also be useful for specific vehicle fleets; in fact the cellular/s~te1lite configuration is expected to be most cost- effective for the initial implement~tions of the system. In the foreseeable future the relay satellite 16 shown in Figure lA, lB and lC will be the MSATTM (Mobile SATellite link) owned by Telesat MobileTM Inc., with a 1995 launch date projected. Satellite transmit and receive module 14 will communicate with the satellite 16 and hence the base co.,l~ulel 18 using the commercial Packet DataTM service that MSATTM will carry. The s~tellite transmit and receive module 14 will transmit at a frequency range between 1626.5 and 1660.5 MHz and receive at a frequency range between 1525 and 1559 MHz. The alarm 13 may be a physical button (not shown) which would, for instance, be in a secreted place such as under the dash for use in criminal assault or other dangerous situations. In addition, alarm may be generated on the basis of a measurement made by or available to the vehicle computer 12, such as miles travelled, time elapsed, or GPS-~et~rmined position. In these cases the vehicle computer 12 would be pre- programmed to generate an alarm when such parameters were reached. As well as vehicle co~ ler 12-generated alarm functions, the vehicle computer 12 can be called at any time by the base computer 18 and interrogated for GPS data. It can also be continuously monitored when used in fleet management situations. The embodiment illustrated in Figure lC in which the vehicle computer 12 has a choice of cellular or satellite communications is shown in more detail in Figure 2 which is a block diagram generally indicated as 40 of an example of a vehicle data bus 42 and various attached hardware and processors, numbered 44 through 56 Note that these components are in general commercially available, and it is the configuration of the ~ 2133673 system that is unique. Thus the various parts to be described will appear with different voltages, amounts of memory, and so on, dependent on the specific use or specific commercial logic boards available. In the present example the feeders of and from data bus 42 consist of a: Power Supply Module 44; nominally of 12V DC input but in practice ranging from 5.5V to 25V DC; with output voltages of +SV and +3V; Flash (volatile) memory 45; of 512K; Static RAM (Random Access Memory) 46; of 512K; Real Time Clock Chip With Watch Dog Timer 47; to initi~li7P the GPS module 50 (described below) after a cold start; to reset the processor; and to report to a base station after specified time intervals; iSBX BUS (8 Bit) 48; a connector and appropliate logic to support an IntelTM specification AP-96 iSBX expansion bus; providing customization and expansion capabilities for specific customer applications; System Controller 49; using the IntelTM TS80C188EB microprocessor in the 80 pin PQFP package as a system processor; Global Positioning by Satellite (GPS) Receiver Module 50; a Rockwell International MicroTrackerTM (RockwellTM part #TU-D150-041); GPS Antenna 51; Cellular Modem Module 52; a custom HayesTM AT command-set compatible 2400 BAUD card; Cellular Antenna 53; Satellite Transceiver Module 54; custom or third-party, compatible with the Packet DataTM service that MSATTM will provide; Satellite Antenna 55; and System In Out (I/O) 56; including Alarm, Ignition, RS-232 Port(s), and Status 2133673 LED's (these are only listed in Figure 2, not shown graphically) Two important features of the GPS emergency signal system illustrated in Figure 2 can be expanded upon further. The first is the capability to modify both the hardware and the software inputs into the system data bus 42. The iSBX Bus 48 allows future hardware connections (possibly with built-in software); while the RS-232-Port(s) in the System I/O 56 allow software to be downloaded from a base source, i.e. the base computer 18 shown on Figure 1. This is extremely important, as GPS software vendors have requested a means of adapting user input for specific customer applications. The second feature of the system illustrated in Figure 2 that may be expanded upon is the ope~ting conditions and hence physical requirements of the housing. A small amount of background may be of use: this embodiment has been designed in response to a request by a labourunion representing 15,000 taxi-drivers in three C~n~ n cities, all of whom can be expected to be working in severely life-threatening conditions for periods of time in mid-winter. In terms of the mechanical and electrical needs of the alarm system, this translates to a set-up that can with~t~nd- --extended temperatures (-40 to +85C); --high hl1midity and dust; --constant low levels of vibration and shock; --strong EMI fields (conducted and radiated); --power supply input voltage fl~ctl1~tion (6-24V); --power supply transient spikes (40V in cars; higher in trucks); --momentary loss of GPS satellite information; and --momentary loss of cellular/satellite connection. To address this need, the system has been designed so that all the numbered components indicated in Figure 2, with the exception of the ~ntenn~ 51, 53, and 55, are housed within one protective package small enough to fit under the dash close to the vehicle' s electrical panel (since the driver' s col--pa~ lent is usually the most benign ~ 2133673 location in a commercial vehicle). Other requirements of the system controller 49 of Figure 2 include: --constant standby, even when the vehicle is off; --low power (due to constant standby); --multiple alarm inputs (two fixed alarms, one in the trunk and one in the driver's compartment, plus the intt;~ pl from a base station); --storage of last good fix (due to satellite shadowing by fixed structures); --remote alarm deactivation (from the base station); and --self test and system status indicator. Finally, the antennae are designed to be housed in a single low-profile case. Operation of the embodiment of the emergency tr~n~mi~ion system of the block diagrams, and specifically that of the system with both cellular and relay satellite illustrated by Figures lC and Figure 2, can be inferred from the foregoing but might be snmm~ri7efl as follows: (in this summary, numerical reference will not be made to the Figures since certain physical characteristics will be included that are not illustrated): (a) GPS data is obtained by the vehicle GPS receiver module through GPS antenna on a continuous basis, and fixes are stored in memory in Nonvolatile Ram in the system clock and updated once a second. (b) In an emergency situation, the vehicle driver presses an alarm button in the driver's compartment (or trunk). (c) The system controller registers the alarm. (d) The system controller obtains current GPS data if available; if unavailable due to bridge, tunnel, or structural shielding it obtains the last good fix. (e) The system controller sends the GPS fix and alarm, to the cellular modem module, if within range of a cellular tower; or to the satellite ~ 2133673 transceiver module if not. (f) Either the cellular modem module or satellite transceiver module sends the alarm and GPS data, via the al)pl~,pliate ~ntenn~, to the base station computer; and does so continuously, with new GPS data when available. In the foreseeable future, the relay satellite is the MSAI~M . (g) When the situation has been understood or resolved, but not until, the base station computer sends a coded deactivation message to the vehicle to stop tr~n~mitting data. (h) At any time the base station computer can send a break-in message to the vehicle computer and obtain current GPS data. (I) Further instructions can be sent to the vehicle computer from the base station computer, including software, so that the vehicle computer may transmit GPS data at different instructed times, distances, or in new formats. (J) The vehicle co~ ,uler can be customized and expanded by means of plugged in hardware and software, accommodated by the on-board Intel~M AP-96 iSBX expansion bus. The foregoing is by example only, and the scope of the invention should be limited only by the appended claims.
