Google Exhibit 1009
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`GB2079453A1 _1
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`SPECIFICATION
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`Route selection and guidance apparatus and method
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`10
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`' 5 This invention relates to an apparatus and method for providing a driver of a driver—contro||ed vehicle with
`information identifying successive sections of a route to be followed, so as to enable the vehicle to be driven
`from a selected starting point to a selected finishing point. In the specification the term "vehicle" is intended
`to cover any form of moving craft the route of which over land or sea, or in the air, is dependent on a driver or
`pilot action to direct the craft along successive sections of a selected route.
`Though in the description that follows the invention will be described in relation to the driving of a land
`vehicle along roads, the invention may also be applied to the navigation of boats along waterways or across
`the open sea, and also to the piloting of an air-craft through the sky.
`It has been shown recently by transport planning authorities that in the United Kingdom the distance
`travelled by all vehicles in getting to their destinations is some 6 per cent greater than that which was
`actually necessary forthe performance of the required journeys. Such an over-travel represents a loss to the
`United Kingdom economy of some 1500 million pounds. Hence, a means for enabling this over-travel to be
`reduced would be a substantial benefit to those who make the journeys, and to the UK economy.
`The basic source of route information forthe modern road vehicle driver has been traditionally the printed
`map, and from that the driver (or some one acting for him) has determined, according to his own intuitive
`criteria, and his own personal assessment of factors such as road conditions and congestion, the route that
`he should follow in making any particularjourney.
`Thus, the preliminaries to a road journey included the making ofan analysis and an assessment of the
`possible alternative routes between the starting and finishing positions, and a selection ofthe route to be
`followed, and possibly the writing down of that route for subsequent reference during the journey. This
`involved some considerable time and effort, and for best results an up-to—date knowledge of the geography
`and traffic conditions prevailing on the various route sections shown on the map.
`For the private motorist, particularly, this problem of route selection has been aided by the professional
`motoring organisations, which have provided on request special printed route maps complete with
`accompanying written instructions for the guidance of the driver or navigator during the course of the
`journey. Unfortunately, such route maps and instructions usually required the making of a specific request
`some days before the intended departure on the journey, so that the relevant route could be selected and the
`relevant map sections and instructions compiled for despatch to the intending traveller.
`Furthermore, the following of such a set of route instructions required the driver or nagivator to be ever
`attentive as to his exact position on the route map and instruction set, so that he could anticipate his arrival
`at the next mentioned cross—roads orturning. Moreover it was necessary for him to constantly memorize the
`next guidance instruction apertaining to the next route section.
`Though such special route maps and guidance instruction sets were of great benefit to the motorist, they
`had the disadvantage of involving another party in the selection and preparation of a route and also that
`once prepared the driver could not expeditiously or easily modify the map and guidance instruction set to
`deal with unforeseen conditions or events such as for example traffic diversions or adverse road conditions
`due for example to accidents or weather.
`According to a first aspect of the present invention there is provided in or for a vehicle (as hereinbefore
`defined), a route guidance apparatus comprising:-
`(a)
`instruction producing means for producing in sequence from a pre-planned route individual
`route-stage instructions each defining an action to be taken by a driver of a vehicle at the end of an
`associated route-stage, each such instruction including a reference signal representing the intended vehicle
`position at the point along the associated route-stage at which the instruction should be announced to the
`driver for subsequent action by him;
`(bl
`feedback signal producing means for producing feed back signals representative of the progress of
`the vehicle along the route-stage, each such feedback signal being representative directly or indirectly ofthe
`position of the vehicle on said route-stage;
`(c)
`instruction announcing means for announcing to the driver, on its being activated, a said instruction
`represented by output signals of the instruction producing means;
`(d)
`signal comparison means for comparing during each said route-stage said reference and feedback
`signals and for activating said instruction announcing means when said reference and feedback signals
`correspond, thereby to announce to the driver the instruction associated with the said reference signal, and
`(e)
`activating means for activating said instruction producing means thereby to cause it to produce the
`next route-stage instruction in the sequence in place of a current one.
`Said activating means may be driver-operable; though in a preferred apparatus each route-stage
`instruction produced by said instruction producing means also includes an additional reference signal which
`represents the intended vehicle position at the end ofthe associated route-stage, at which position the driver
`should act on that instruction; and there is included comparison means for comparing during each
`route-stage said feedback and additional reference signals and for stimulating said activating means when
`said feedback and additional reference signals correspond, thereby to cause said instruction producing
`65 m rgfofgpduce the next route-stage instruction in the sequence in place of the current one.
`Page
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`GB 2 079 453 A
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`in one form of guidance apparatus according to the present invention said instruction producing means is
`arranged to store a plurality of sets of route-stage instructions for enabling a driver to be guided along
`various routes respectively; and said instruction producing means includes driver-operable route selection
`means for enabling a driver to select from said various routes a specific one along which he wishes to be
`5 guided, said instruction producing means being operative on selection of route to a produce in sequence and
`as required by said activating means the successive route-stage instructions apertaining to the selected
`route.
`
`5
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`Advantageously said route selection means includes driver-operable selection means for identifying the
`starting and finishing positions of a journey for which guidance is required, and means for automatically
`selecting from said plurality of sets of route-stage instructions the set having the driver-identified starting
`and finishing positions, thereby to cause the desired set of route-stage instructions to be produced in
`sequence and as required by said activating means.
`In a preferred form of guidance apparatus according to the present invention said instruction producing
`means includes
`
`a route compiling means for compiling each said pre-planned route on being required by a driver, and
`a driver-operable journey selection means for identifying the starting and finishing positions of a jogrney
`for which guidance is required; and
`said route compiling means includes -
`(a)
`a data processing means,
`(b)
`a map data storage means for storing map data defining and describing the respective road sections
`ofa road system on a predetermined map section, each such road section being a length of road lying
`between adjacent points at which an approaching driver has different courses of action open to him,
`(c)
`a program storage means for storing programs for controlling the operation ofthe data processing
`means, and for causing it to carry out, on request and according to a predetermined optimization criterion, a
`route evaluation and selection process to determine an optimum route between the driver-identified journey
`starting and finishing positions on the said map section, and means for storing that optimum route and
`announcing route-stage instructions appertaining to it in sequence as required by said activating means.
`Preferably, said program storage means has stored within it alternative programs, or program modifiers,
`for enabling the data processing means to carry out on request route evaluation and selection processes
`according to any one of a plurality of different optimization criteria, and there is provided driver—operab|e
`optimization criterion selection means for selecting for a particularjourney to be undertaken the particular
`optimization criterion or criteria to be used.
`Conveniently, said data processing means is also arranged to carry out the functions of the respective
`comparison means for comparing on the one hand said feedback and reference signals, and on the other
`hand said feedback and additional reference signals.
`Said map data storage means may have associated therewith map data entry means for receiving
`removable map data storage elements, whereby data appertaining to any desired area of a map may be
`entered into said map data storage means for use temporarily by said data processing means.
`Vocal input means for receiving a driver's spoken input information identifying a journey to be undertaken
`may be provided, and said data processing means may then be arranged to decode that vocal input
`information and to act upon it in selecting a route for a journey to be undertaken by the driver.
`Preferably, said instruction announcing means is arranged to announce each said route-stage instruction
`in vocal form, and said data processing means is arranged to produce and/or control signals for vocalizing
`said instructions.
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`Said instruction announcing means may be arranged to announce each route-stage instruction in visual
`form.
`
`Said feedback signal producing means may take any one of a plurality of different forms; for example, an
`elapsed-time measuring means arranged to be carried by the vehicle and to be activated by said activating
`means, and to deliver an output vehicle-position-indicating signal dependent on the time that has elapsed
`since last being activated; or alternatively a distance measuring means arranged to be driven by the vehicle
`and to be activated by said activating means, and to deliver an output vehicle—position-indicating signal
`dependent on the distance travelled by the vehicle along the route-stage since last being activated; or
`alternatively an inertial-guidance position determining means arranged to be carried by said vehicle and to
`compute from vehicle motion the position ofthe vehicle, and to provide an output vehicle-position-
`indicating signal dependent on said position for comparison with position indicating signals constituted by
`said reference and/or said additional reference signals incorporated in said route-stage instructions; or
`otherwise a vehicle position determining means arranged to be carried by said vehicle and to compute, from
`bearings of objects disposed externally ofthe vehicle on or around the earth's surface, the position of the
`vehicle, and to provide an output vehic|e—position-indicating signal for comparison with position-indicating
`signals constituted by said reference and/or said additional reference signals incorporated in said
`ro ute-sto rage instructions.
`Preferably, each said route-stage instruction is represented in electrical signal form, and said reference,
`additional reference, and feedback signals comprise electrical signals.
`According to a second aspect to the present invention a method of guiding a driver of a vehicle (as
`65 hereinbefore defined) along a multi-stage route between journey starting and finishing positions, comprises -
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`if.
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`GB 2 079 453 A
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`(a) generating and storing for said route a sequence of individual route-stage instructions each defining
`an action to be taken by the driver at the end of the associated route-stage, and each including a reference
`signal representing the intended vehicle position at the point along the associated route-stage at which the
`instruction should be announced to the driver for subsequent action by him;
`(b)
`extracting a said instruction that is associated with a first route-stage and holding it ready for
`announcement to the driver;
`(c) generating a feedback signal representative of the progress or position of the vehicle along the
`route-stage;
`(cl)
`comparing said reference and feedback signals,
`(e)
`announcing the extracted instruction to the driver when said reference and feedback signals
`correspond;
`(f)
`indicating when the vehicle has passed into the next route-stage; and
`(g)
`repeating cyclically in turn the steps (b) to (f) above for the second and subsequent instructions in the
`sequence.
`Each said route-stage instruction generated in said step (a) above may also include an additional reference
`signal representing the intended vehicle position at the end of the associated route-stage, at which position
`the driver should act upon that instruction; and
`the step (f) above may then comprise comparing said feedback and additional reference signals and
`indicating when said feedback and additional reference signals correspond that the vehicle has passed into
`the next route-stage.
`Such methods may also include the preliminary step of-
`specifying the starting and finishing positions of a journey for which guidance is required, and the criterion
`or criteria to be used in selecting an optimum route between those positions, and
`in the said step (a) said sequence ofinstructions is obtained by generating from stored map data defining
`and describing the respective road sections of a road system (each such section being a length of road lying
`between adjacent points at which an approaching driver has different courses of action open to him) the
`optimum route between the specified starting and finishing positions and based on the specified
`optimization criterion or criteria, and storing the route-stage instructions for the successive route—stages
`making up that optimum route.
`Other features and advantages of the present invention will appearfrom the description that follows
`hereafter, and from the claims appended at the end of that description.
`One embodiment ofthe present invention for providing route selection and driver guidance instructions in
`or for a road vehicle will now be described by way of example and with reference to the accompanying
`diagrammatic drawings, in which:-
`Figure 7 shows in outline a motor car in which a route selection and driver guidance system according to
`the present invention is installed; and
`Figure 2 shows schematically the various components of that system, and the manner of their
`interconnection.
`Referring now to the drawings, a motor car 10 has installed in it a route selection and driver guidance
`system 12, which includes a drivers’ console 14fitted in a forward position convenient for a driverto operate,
`obseve and hear, and an associated equipment module 16 which is mounted preferably alongside the
`console, though if required its constituent components could be mounted elsewhere in or around the car.
`The system 12 is shown in more detail in Figure 2, from which it will be seen to include a digital data
`processor 18 which is connected to receive input information concerning a route to be determined from
`(a)
`a driver's function control and data entry module 20 having "function control” push-buttons 22, and
`"data entry" keys 24,
`(b)
`a "map data” input module 26 for receiving a magnetic storage element 28 (for example a tape or
`disc) carrying data defining, describing and qualifying each and all ofthe road sections li.e. lengths of road
`between pairs ofadjacent road intersections) included in a particular map section ofthe United Kingdom
`50 road system, and
`(c)
`a driver's microphone 29 for inputting a driver's vocal instructions.
`Associated with the data processor 18 is a read-only, random—access, memory (”ROM"), in which is stored
`the operating programs for controlling the operations of the process, and various programs (and program
`modifiers) for use in the processor for determining alternative routes between driver—specified starting and
`55 finishing positions, according to any one or more of a variety of selected overriding criteria, e.g. shortest
`distance, minimum running time, best fuel consumption, avoidance of urban roads or motorways.
`Also associated with the processor 18 is a data storage unit 32 (preferably of the random—access kind) for
`storing data inputted to it via the processor 18 by the map data input module 26.
`The output of the processor 18 is transmitted to a driver's visual display unit 34 for providing visual
`50 guidance instructions, and/or to a driver's loudspeaker (or earphone) 36 for providing vocal guidance
`instructions. A vocabulary of sound producing signals (representing various basic phrases, words and
`syllables) is stored in a sound vocabulary unit 38 for use at appropriate times by the processor in formulating
`vocal guidance instructions fortransmission overthe loudspeaker.
`Guidance instructions to be transmitted to the driver via the display and/or loudspeaker are coordinated
`th pro ress (that is the position) ofthe vehicle along the selected route, by means of output signals
`wi
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`GB 2 079 453 A
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`provided by one or more position feed-back devices 40. Such devices may comprise on the one hand a
`relatively simple ”e|apsed-time" indicator 40 A, or a ”distance-trave||ed" indicator 40 B driven from a
`transmission system (e.g. a propeller shaft) of the vehicle. Alternatively the position feed-back device may
`comprise a more sophisticated device such as for example an integration system 40 C incorporating means
`5 for integrating changes in vehicle compass heading and speed and providing in response thereto vehicle
`position map coordinates; or an inertial navigating system 40 D likewise arranged to provide vehicle position
`map coordinates; or an earth satellite navigation system 40 E arranged to provide an output derived from
`bearing observations of earth satellites; or a radio navigation system 40 F for providing output signals based
`on the observation of bearings of specific radio beacons.
`The system 12 is connected for power supply through an ON/OFF switch (not shown) to the electrical
`system of the vehicle.
`-
`The "function control” buttons 22 (referred to hereafter as "function buttons") include the following, for
`effecting the following operations:-
`
`10
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`15
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`(a)
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`an "Advance" button
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`a "Step-back" button
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`a "Confirm” button
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`a "Start" button
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`7
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`a "New Data” button
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`a "CANCEL” button
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`a "Calibrate" button
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`proceed to next guidance
`instruction;
`
`step back to the prece-
`ding road section (this
`allows the instructions
`for that road section to
`be reviewed);
`repeat current instruct-
`ion;
`give initial instruct-
`ion for starting the
`journey;
`receive new starting and
`finishing position data
`aboutto be keyed in;
`cancel the previously
`stored selected route
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`and adopt the newly se-
`lected route; and
`adjust multiplier to re-
`calibrate the distance
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`output signals derived
`from the distance feed-
`back device 40 B.
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`45
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`The data-entry keys 24 include keys for enabling the driving to feed—in:—
`(a)
`the names ofthe starting and finishing positions ofthe desired journey (or alternatively codes
`representing or designating those names, for example the map coordinates ofthose respective positions);
`(b) which ofthe various available optimizing criteria is/are to be used in assessing and selecting the
`optimum route from the various possible routes;
`(c) other data such as latest running cost per mile based on car and engine size, and the latest fuel prices.
`The map data storage element 28 incorporates for every road section in a particular map section data
`comprising:-
`(1)
`the map coordinates ofthe ends of the road section;
`(2)
`the length ofthat section;
`(3)
`the road name (ifany);
`(4)
`the road number (if any);
`(5)
`the section travelling times using the respective criteria;
`(6)
`the costs of travelling along the section for each of the travelling times referred to at (5) above; and
`(7)
`the direction ofthe section.
`in use, after first energizing the system 12, the driver wishing to travel between starting and finishing
`points A and B on the same map section selects the map storage element 28 appropriate to that section and
`inserts it into the map data input module 26. Thereafter, he activates that module to cause the map data to be
`read from that storage element via the processor into the data storage unit 32, where it is stored for use later.
`Then using appropriate data entry keys 24 the driver keys—in the identities of the starting and finishing
`places A and B, and also the criterion/criteria that he wishes the system to use in determining the selection of
`his route, for example that he wishes to travel from A to B in the shortest running time (rather than for
`example along the shortest distance).
`Now, having been given the starting and finishing positions, the processor 18 proceeding under the
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`GB 2 079 453 A
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`5 c
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`ontrol of the ROM 30 and using the data defining, describing and qualifying the various road sections as
`stored in the data storage unit 32, assembles in turn various possible routes between the starting and
`finishing positions, and then using the selected optimization criterion/criteria (stored in the ROM) compares
`one route with another to find that route which provides the optimized selected condition/conditions.
`The identities of the road sections constituting this optimized route are then stored in the data storage unit
`32 for subsequent use in guiding the driver section by section along that route.
`On depression of the ”start" button, the first and second road sections ofthe stored route are extracted
`from the data storage unit 32 together with their relevant particulars, and a first guidance instruction
`identifying the road, and its direction, to be taken in order to leave A is formulated and announced to the
`driver. Thereupon thejourney may be commenced.
`A second guidance instruction, to instruct the driver what action is required at the junction of the first and
`second road sections, is also formulated and stored, until replaced later, in the data storage unit 32.
`Alongside the second instruction are assembled (a) the distance to be travelled by the vehicle before the
`second instruction is to be announced to the driver, and preferably also (b) the distance at which this second
`instruction is to be acted upon by the driver. The said distances may also be accompanied, if required, by the
`map coordinates of therespective positions at which said second instruction is to be announced and acted
`upon.
`These distances and/or corresponding map coordinates are compared continuously in the processor 1.8
`with the respective distances and/or map coordinates that are being supplied continuously by the
`corresponding vehicle position feed-back devices 40, and respective "annunciation” and ”change road
`section" control signals are emitted by the processor when the corresponding feed-back distances and/or
`map coordinates equate with the respective stored distances and/or map coordinates.
`The first control signal ("announce guidance instruction”) operates to cause the said second guidance
`instruction to be announced to the driver, so that he may shortly act upon it, whilst the second ofthe control
`signals ("change road section”) is used to automatically cancel the second instruction, preferably only if the
`system detects or has been advised by the driver that the instruction has been correctly acted upon, or ifthe
`system has no indication that the instruction has been carried out or properly carried out, to advise the driver
`of the need for (and also the nature of) appropriate corrective action.
`Instead of providing for the automatic cancellation ofthe second guidance instruction, by causing the
`processor to access the vehicle's movement at and about the position for taking action, and comparing it
`with the guidance instruction, such cancellation may be made dependent instead upon action (for example
`depressing the "advance" button) by the driver to indicate that he has acted upon that guidance instruction
`and is now ready to receive at an appropriate instance the next (third) guidance instruction.
`The third guidance instruction is produced by the processor 18 afterfirst requesting and receiving into its
`own internal memory from the data storage unit 32 the identity and relevant particulars ofthe third road
`section, that third instruction then being deduced and formulated by the processorfrom a comparison of the
`data concerning the junctions of the second and third road sections with each other. This third instruction
`includes the said distances (and where desired, the corresponding map positions) to the respective positions
`for announcing, and, where appropriate, for acting upon this third guidance instruction.
`The third guidance instruction is announced to the driver automatically when the processor detects
`coincidence ofthe distance travelled along the second road section by, or ofthe position on that road section
`of, the vehicle, with the annunciation distance or position identified within the third guidance instruction.
`Further successive guidance instructions are produced in turn by the processor each time an indication
`(automatic or driver-originated) is received by the processorthat the last instruction has been correctly acted
`upon, and the identity and relevant particulars of the next road section ahead have been subsequently
`received by the processor from the data storage unit 32.
`Each successive guidance instruction is announced to the driver automatically when the processor detects
`coincidence of the distance travelled along a current road section by, or of the position on that road section
`of, the vehicle, with the annunciation distance or position identified with that guidance instruction.
`Typical instructions and their associated distance data for travelling from the town of Guildford to the town
`Dorking are shown in the following Table.
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`GB 2 079 453 A
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`7
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`n the event that the driver finds that road, weather, or other conditions are undesirably impeding his
`progress along the route, it is possible for him to request the processor, whilst continuing to store the
`_‘ presently selected route, to work out a new route between his present vehicle position and his destiantion B,
`either via some driver—selected intermediate position which lies offthe present selected route, or avoiding
`’5 the road sections ahead on which travelling difficulties are known (for example, from a broadcast traffic
`news bulletin) to exist. The newly selected route can be adopted by depressing the "Cancel" button.
`In the event that a projected journey extends from one map section to another, a driver must seek a route
`on the first map section to some driver—selected, convenient, intermediate position on or nearthe boundary
`ofthat map section, and after completing that part of his journey on the processor-selected route, enterthe
`10 map data appertaining to the second map section (afterfirst inserting the appropriate map storage element
`28), and then enter that intermediate position as his starting position forthe second part of his journey, as
`well as his final destination. Thereby he will be guided along an optimized route between the intermediate
`position and the final destination.
`Alternatively, the apparatus may be modified to include a larger data storage unit 32 capable of holding
`15 the data oftwo map sections, and then to receive successive map data entries from the two map sections as
`stored on two different map data storage elements 28. In that way, the processor is enabled to analyse and
`select an optimum route between starting and finishing points which are disposed on adjacent map sections
`respectively.
`The guidance instructions may be announced to the driver either vocally via the loudspeaker or earphone
`20 36, or visually via the visual display unit 34, orthey may be announced simultaneously using both visual and
`vocal annunciating means. The visual display unit 34 may be arranged to display an instruction only once
`and for a limited period oftime, or repeatedly at intervals during the period of its currency.
`Furthermore, the processor may be arranged to maintain the visual display unit energized to display the
`next guidance instruction from the time of its formulation by the processor until the time of its subsequent
`25 cancellation by the automatic or driver-produced "action-acted-upon” signal.
`Alternatively, the processor may be arranged to energize the visual display unit only temporarily on
`formulation ofthe next guidance instruction, and to subsequently re-energize it at the said detected time for
`announcing that instruction.
`Where an instruction is not displayed continuously, as mentioned above, from the time of its formulation
`30 to the time of its cancellation, the driver has the option at all times to look ahead by depressing the "confirm”
`function button, whereby to cause the current (that is the next to be acted upon) instruction to be announced
`temporarily by either or both of the vocal and visual means (or in the case of the visual means, even through
`to the time of acting on that instruction).
`The processor may, if desired, be connected with the control system for operating the vehicle's direction
`35 indicators, and be arranged to automatically energize at the appropriate moment the appropriate direction
`indicators in accordance with the current guidance instruction.
`It will be appreciated from the foregoing that with the system specifically described above:—
`(a)
`the driver has available to him in his vehicle, in the form ofthe map storage elements 28, a complete
`road system of the relevant area, which system can be searched for any journey between any two points in
`40 that road system, according to one or more optimization criteria, and that the searching can be carried out
`very quickly and at any time before or during a journey to meet changed or changing conditions, as forecast
`or actually met on the roads;
`(b)
`the driver is relieved ofthe need to keep track of his position on the map and moreoverto memorize
`successive instructions; and
`(c)
`the selection of the optimum route is carried out methodically, reliably, and exhaustively, and is
`based on information recorded in map storage elements that are capable of being updated from time to time
`as the need arises.
`The data storage unit 32 may be of any suitable kind, including those of the sequential access variety, for
`example a bubble memory.
`The map data may be recorded on any convenient form of data storage element 28, for example on discs
`or tapes. Tapes offer the advantage that they could be inserted in and read by tape decks that are
`increasingly being installed in vehicles for the purpose of playing music and speech.
`Alternatively, the map data storage element may take the form of a "library module” chip storage device,
`similar to those now being used in small pocket calculators.
`Whilst the map data storage elements 28 have been disclosed above as covering various contiguous, and
`possibly overlapping, sections of a road system, it should be appreciated that such sections of a road system
`may each cover a fairly large area ofthe country, or alternatively a much smaller area. The former may be
`used to enable route selection and