NZ533764A - A method of determining distance travelled by an object - Google Patents

Abstract

A method of determining the distance travelled by an object, with particular application to commercial vehicles subject to haulage levies, is disclosed. The method includes the steps of receiving a first distance signal and an independently generated second distance signal, determining a distance calculation coefficient based on the second signal, using the first signal and calculated coefficient to determine the distance travelled in a particular time period, and transmitting the determined distance value to a remote entity. When applied to a vehicle the first signal may be generated by a tachometer and the second signal may be obtained from a GPS device in order to calibrate the tachometer to produce reliable distance data. The remote entity may be a billing centre that converts the distance data into a corresponding road user charge for the vehicle.

Description

533 J 64 PATENTS FORM NO. 5 Fee No. 4: $250.00 PATENTS ACT 1953 COMPLETE SPECIFICATION After Provisional No: 533764 Dated: 25 June 2004 A METHOD OF DETERMINING DISTANCE TRAVELLED BY AN OBJECT WE E-ROAD LIMITED, a New Zealand company of CI- TVD, The Stables, 2 Collingwood Street, Ponsonby, Auckland, New Zealand hereby declare the invention for which We pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: 1a Intellfctusl Preoertv Offic® of N.Z. t - JUL 2005 received *10047939510* A METHOD OF DETERMINING DISTANCE TRAVELLED BY AN OBJECT TECHNICAL FIELD This invention relates to a method of determining the distance travelled by an object, and in particular, though not solely, to a method of determining the distance 5 travelled by a vehicle, and even more particularly, by commercial vehicles which are subject to haulage levies.

BACKGROUND ART Government authorities of many countries throughout the world, including New Zealand and Switzerland, levy road user or haulage charges against commercial 10 vehicles, such as long haul trucks. In general, the road user charges are levied against vehicles on a per kilometre (or mile) travelled basis. Accordingly, it is necessary that distances travelled by vehicles which are subject to such levies are accurately determined and recorded.

Hubodometers are commonly used for determining the distance travelled by a 15 vehicle. A hubodometer is mounted to the hub of a wheel and records and displays the distance travelled by a vehicle based on the number of wheel rotations. Therefore, the output of a hubodometer provides an indication of distance travelled which is effected by variables such as the tyre pressure and rim (wheel) size. Accordingly, most of these meters are mechanically calibrated and 20 certified by government authorities for a specific tyre pressure and rim size. Inaccuracies in either of these parameters and normal tyre wear can result in erroneous levying of road user charges based on hubodometer output.

The use of a Global Positioning System (GPS) provides an alternative to the sole reliance on hubodometers for accurate distance measurement. However, GPS is Intellectual Property Office of N.Z. 2 0 fl ?%? W- i 1 jCUUO RhGbl V'bD limited in application as a result of interference caused as a vehicle passes through tunnels or "urban canyons" which do not have effective GPS satellite coverage.

Inaccurate levying of road user charges may also be caused by unauthorised tampering with distance measurement devices, such as tachometric meters (or 5 parameters used for calibration of a tachometer) and/or GPS components (such as transceivers or antennae).

In the case of the New Zealand road user charge system, the operators of commercial vehicles must ensure they pay in advance and have a credit road user charge balance for the vehicles they operate. It is an offence to operate such 10 vehicles without having road user charges paid up to date and in a credit balance. This therefore creates a cash flow issue for businesses, which need to have funds tied up in road user charges prior to such funds needing to be expended.

As can also be appreciated by those skilled in the art, the use of current hubodometer technology requires a physical inspection of each meter to determine 15 the distance travelled by a vehicle. This can be time consuming for vehicle operators who need to ensure that they maintain a credit balance for road user charges and must therefore check hubodometers relatively frequently. This situation is also aggravated where trailer units are towed as the vehicle operator has to again physically inspect the hubodometer at the far end of the vehicle every 20 time they are required to determine the distance travelled by the trailer. This problem is also experienced by law enforcement officers who again must physically inspect the hubodometer involved to check whether a vehicles road user charges are currently in credit.

It is therefore an object of the present invention to provide a method of determining 25 the distance travelled by a vehicle which goes at least some way towards 2 overcoming the above disadvantages or which will at least provide the public and/or industry with a useful choice.

All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any 5 reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common 10 general knowledge in the art, in New Zealand or in any other country.

It is acknowledged that the term 'comprise' may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term 'comprise' shall have an inclusive meaning - i.e. that it will be taken to mean an inclusion of not only the 15 listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term 'comprised' or 'comprising' is used in relation to one or more steps in a method or process.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

DISCLOSURE OF INVENTION Accordingly, in a first aspect the invention may broadly be said to consist in a method of determining distance travelled by a moving object, the object including means for outputting a first distance signal indicative of distance travelled, comprising the steps of: i) receiving the first distance signal, 3 ii) receiving a second distance signal generated independently of the first distance signal, iii) determining a distance calculation coefficient based upon the second distance signal, and iv) using the first distance signal and the distance calculation coefficient to determine distance travelled in a predetermined period.

Preferably, the object includes a rotating means in contact with the ground, and the first distance signal provides an indication of the number of rotations of the rotating means.

Preferably, the first distance signal comprises a series of pulses, each wheel rotation corresponding to one or more pulse.

Preferably, the second distance signal provides an indication of position at predetermined times.

Preferably, the second distance signal is generated by a global positioning system.

Preferably, the distance calculation coefficient is determined by summing pulses from the first distance signal which are received during the time between two or more indications of position provided by the second distance signal, and dividing the distance between the two or more indications of position by the sum of the pulses.

Preferably, the distance travelled in a predetermined period is calculated by multiplying the number of pulses in the first distance signal during the predetermined period by the distance calculation coefficient. 4 Preferably, the distance calculation coefficient is determined over a predetermined distance travelled by the moving object, wherein the predetermined distance is calculated based upon the second distance signal.

Preferably, an initial estimate of the distance calculation coefficient is determined 5 over a first distance.

Preferably, the initial estimate of the distance calculation coefficient is substituted by a revised value which is determined over a second distance, greater then the first distance.

Preferably, the initial estimate is only substituted once a predetermined number of 10 revised values of distance calculation coefficient, each determined over respective said second distances, are within a predetermined percentage of one another.

Preferably, if the second distance signal is unavailable, the distance travelled in a predetermined time period is calculated by multiplying the number of pulses in the first distance signal during the predetermined period by a predetermined distance 15 calculation coefficient.

Preferably, if the first and second distance signals are unavailable a third distance signal detects whether the object is moving and records an indication thereof.

Preferably, the third distance signal is generated by an accelerometer positioned in or on the object.

In a second aspect, the invention may broadly be said to consist in an electronic hubodometer incorporating means to implement the method according to the first aspect.

Preferably, said means comprise control means which executes a computer program which carries out the method according to the first aspect.

In a third aspect, the invention may broadly be said to consist in a system for determining distance travelled by a moving object, comprising: i) an electronic hubodometer according to the second aspect, ii) means for generating said first signal, and iii) means for generating said second signal.

Preferably the means for generating said first signal may include a rotation sensor which incorporates an inductive energy generator, and an energy storage means, and a rotation detection transducer.

Preferably the inductive energy generator of the rotation sensor is adapted to 10 supply energy to the energy storage means when the object for which a distance to be determined is moving. Those skilled in the art should however appreciate that an energy storage means such as a battery may be required to supply energy when the object is not moving, potentially to maintain the storage information in some instances.

Preferably energy supplied from the energy storage means may be used to power the operation of the rotation detection transducer.

According to a further aspect of the present invention there is provided a system for determining distance travelled by a moving object substantially as described above wherein an electronic hubodometer integrated into said system is adapted to 20 transmit distance travelled information to a remote entity, and to receive from said remote entity an indication of a usage charge balance associated with the moving object. 6 BRIEF DESCRIPTION OF DRAWINGS Further aspects of the present invention will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings in which: Figure 1 is a schematic block diagram illustrating the method of determining the distance travelled by an object in accordance with a preferred embodiment of the present invention, and Figure 2 is a schematic block diagram of apparatus suitable for carrying out the method of the present invention.

BEST MODES FOR CARRYING OUT THE INVENTION The present invention determines the distance travelled by a moving object, and more specifically, commercial vehicles that are subject to road user charges, such as long haul trucks or lorries adapted for the transportation of goods. However, those skilled in the art should recognise that the present invention may equally and 15 effectively be applied to determine distance travelled by a variety of moving objects and is not limited in application to road bound vehicles adapted for the transportation of goods.

With reference to Figure 1, determination of the distance travelled by a vehicle in accordance with a preferred embodiment of the present invention is shown.

Accumulator 1 receives a first distance signal transmitted by a moving vehicle. Such a signal may be output by a device, such as a tachometer, associated with/or positioned within the moving vehicle. The signal may provide an indication of the number of rotations of a rotating means, such as a wheel or wheel shaft, associated with the vehicle and which is in contact with the ground. The first 25 distance signal may be provided as a series of pulses or "ticks" where each 7 revolution of the wheel (shaft) corresponds to one or more pulses or "ticks". Each rotation of a wheel shaft may be sensed by rotation sensor 2. Such pulses or ticks may be output by electronic or mechanical transmission means attached to the wheel shaft of the moving vehicle. It is these pulses or "ticks" which provide input 5 to a tachometer.

In alternative embodiments the first distance signal may be a pulse output from a tachometer or a rotational sensor for example of an ABS braking system. Alternatively, the first distance signal may be provided by a speed and/or distance signal output by an Engine Management Computer onboard the vehicle.

Accordingly, as the vehicle moves, the wheel shaft (and the associated wheel) will rotate and the number of revolutions made by the wheel shaft and sensed by rotation sensor 2 may be used to estimate the distance travelled by the vehicle. Such estimations may for example be made based on specific parameters of the wheel (such as rim size and, assuming it is a pneumatic tyre, its associated tyre 15 pressure) and tread wear. However (as will be explained below) the present invention utilises an additional distance estimating signal to improve the accuracy and/or reliability of the first distance signal.

The present invention may also include storage and processing means so that the number of pulses sensed by rotation sensor 2 and transmitted in the first distance 20 signal (for example over a predetermined period of time), may be correctly aggregated at accumulator 1.

A second distance signal which is generated independently of the first distance signal may also be received. The second distance signal may provide an indication of the respective positions (such as x, y and z co-ordinates) of the 25 vehicle at predetermined times so that by appropriate trigonometric calculation, the distance travelled by the vehicle may be made. 8 The second distance signal may be generated by a global positioning system (GPS) receiver for example. GPS is a radio navigation system that enables land, sea or airborne vessels (such as automobiles, aeroplanes and boats) to determine their near exact location and velocity. GPS utilises satellites that contain a 5 computer, an atomic clock, and a radio so that satellites associated with the GPS are adapted to continually broadcast to GPS receivers their respective changing position and time. Depending on the availability of satellite signals it may also be possible for the GPS receiver to determine altitude as well as geographic position and changes therein.

In an alternative embodiment, the second distance signal may be generated by the Galileo Positioning System, which is the planned European equivalent to the United States GPS system.

By placing a GPS receiver in a moving vehicle, a computer associated with the receiver "triangulates" its own position by obtaining bearings from three or more 15 satellites. The transmitted signal may provide a geographic position (including longitude and latitude) accurate to within a few metres. Accordingly, accurate estimations of the distance a vehicle has travelled may be made by reference to changing positional data.

Processing means 3 may be used to calculate a distance calculation coefficient 20 which may be used to calibrate the tachometer and/or the output of the electronic or mechanical transmission means associated with the tachometer to produce distance data. This ensures that the distance determined in accordance with the first distance signal is accurate. The distance calculation coefficient may also be used to detect whether any of the components of the system which generate 25 signals used to determine distance travelled have been tampered with. 9 The distance calculation coefficient is determined by summing the pulses from the first distance signal which have been received during a time period between two or more indications of position provided by the second distance signal, and then dividing the distance between the two or more indications of position by the sum of 5 the pulses.

The distance between the two or more indications of position may be determined by trigonometric methods using the GPS co-ordinates. Preferably, the distance calculation coefficient is determined while the vehicle is moving in a substantially straight line with little or no deviation in altitude as this significantly improves the 10 simplicity and accuracy of the distance calculation from the GPS co-ordinates. Furthermore, because GPS accuracy is expressed as a fixed distance (for example, within a few metres), the percentage accuracy of a distance calculation between two GPS co-ordinates will improve as the distance increases. Accordingly, preferably the determination of the distance calculation coefficient is 15 carried out over a significant distance.

For example, when the system is first initialised, in order to quickly obtain a first estimate of the distance calculation coefficient the calculation may be carried out over a GPS determined distance of around 200 metres in a substantially straight line (known means may be provided for sensing deviation in direction). In order to 20 improve the accuracy of this initial estimate, an average of multiple estimates (for example three) could be determined. This initial estimate (or averaged initial estimate) will then be utilised in determining distance travelled (as explained below) until such time as conditions (such as distance travelled) enable a more accurate value for the coefficient to be determined.

Once the vehicle has travelled a greater distance (for example 1000 metres) in a substantially straight line at relatively constant altitude, further estimates of the coefficient will be determined. To further improve accuracy, these 1000 metre estimates may be averaged and once the coefficient's value is substantially constant (for example, the last 10 coefficients calculated over respective 1000 metre distances are within 2% of each other) then the previously determined initial estimate (over 200 metres) is substituted by the new value and distance 5 calculations carried out with the new coefficient. However, in the background, the 1000 metres estimates will continually be determined and if for example three consecutive coefficient values are found to be outside a predetermined range of the currently used coefficient (such as 2% or more greater or lesser) the "recalibration" occurs. In recalibration the above described process of determining 10 coefficient estimates over 1000 metres occurs once more. Once again, the coefficient being used to calculate distance travelled is only updated once say 10 consecutive coefficient values are within a tight range (say 2%) of each other during recalibration.

The distance travelled in a predetermined period is determined by applying the 15 distance calculation coefficient to the first distance signal (which comprises for example pulses). This requires that the number of pulses in the first distance signal received during the predetermined period is multiplied by the distance calculation coefficient (which has units of pulses per metre or kilometres) by multiplier 4.

The total distance travelled by a vehicle is the sum of all distances travelled in a plurality of predetermined time periods. Accordingly, the distance travelled in a predetermined period is then forwarded to first summing means 5, which adds that distance travelled (as output by multiplier 4) in one time period with prior distances recorded at aggregator 6. The new total distance travelled is then recorded in 25 recording means 7 which provides an updated total to aggregator 6. The aggregator 6 therefore maintains an updated running total of total distance 11 travelled and it is upon this running total of kilometres or miles travelled that road user charges may be levied.

Ineffective GPS satellite coverage arising due to interference caused as a vehicle passes through tunnels or "urban canyons" or by accidental/purposeful 5 manipulation of the GPS receiver and/or antenna may cause the second distance signal to become unavailable. During such periods the distance travelled during a predetermined time period may be calculated by multiplying the distance corresponding to number of pulses in the first distance signal by a predetermined distance calculation coefficient previously determined by the above process or 10 stored in non-volatile memory associated with the system.

A third distance signal may be output and used to detect when the vehicle is moving during periods in which both the first and second distance signals are unavailable. The third distance signal may correspond to output of an accelerometer positioned in or on the moving vehicle. In use, output from the 15 accelerometer will indicate that the vehicle is currently in motion although as it is not receiving first and/or second distance signals and that it is not currently possible to determine the distance being travelled. Accordingly, the accelerometer may operate an internal sensor. Such occurrences may be indicative of a system fault or that the tachometer or GPS signal receivers have been tampered with. 20 During such periods a vehicle may discharge a visual or audible alert to warn a driver that the vehicle is in an unauthorised travelling mode and the fact that the first and/or second distance signal is not being received may be recorded along with an indication of whether the accelerometer is registering vehicle movement.

In an alternative embodiment the third distance signal may be provided by vibration 25 sensors (associated with the moving vehicle), a gyroscope or Piezo electric devices. 12 The present invention also includes an electronic hubodometer incorporating means to implement the above described method. A schematic block diagram of the electronic hubodometer 10 is shown in Figure 2. The electronic hubodometer 10 may be positioned within the cab (not shown) of a vehicle and is adapted for 5 measuring distance travelled by the vehicle via motion sensor 11.

The motion sensor 11 may be adapted to sense the number of revolutions of a wheel shaft of a vehicle and may also include means for transmitting this information as a first the signal to the tachometer. Those skilled in the art should appreciate that this information may be transmitted by a physical wire link in some 10 embodiments or alternatively by a wireless radio frequency transmission in other embodiments if required.

The hubodometer may incorporate an on-board physical display 12, such as an LCD screen, which incorporates a variety of indicators to indicate key performance and security data, such as when the vehicle is operating correctly. This display 15 may be used to display information relating to the travelled distance determined in conjunction with the present invention.

The display panel may be positioned in such a way that it is visible through the vehicle's windscreen. In this configuration both a vehicle operator and a law enforcement officer may easily see from the display (preferably mounted within the 20 vehicles cab) the distance travelled by the vehicle. Furthermore in other embodiments where a trailer is towed, this display may also be linked to a further electronic hubodometer which may display an indication of the distance travelled by the trailer in conjunction with the distance travelled by the truck used.

The hubodometer 10 is adapted to receive and store the first, second and/or third 25 distance signals at storage means 13 and then process the signals received in accordance with the above method. Furthermore, the storage means 13 is 13 adapted to keep a log or record of tachometer output, distances travelled, positional data received from the GPS and other information, including security and audit logs (such as GPS locations visited by the vehicle), generated in conjunction with the present invention.

Furthermore, the electronic hubodometer 10 may incorporate a GPS receiver 20 which is adapted to receive positional data from a GPS transmitter 14. Such positional data may be received as a second distance signal (as discussed above).

To facilitate road user charging procedures each hubodometer 10 has associated with it a unique identifier which corresponds to a vehicle owner or operator billing 10 account.

The hubodometer 10 may interact with an interface 15 which is adapted for detecting the connection and disconnection of additional transportation units, such as trailers, to a vehicle. Such an interface may be adapted to record an event log capturing the connection/disconnection date, time and an identifier associated with 15 each trailer or unit. As road user charges are normally levied on a vehicle class basis, the number of and identity and configuration of each trailer concurrently connected to a vehicle is an important factor when determining road user charges. Such an interface may be provided by a single communications data line which is run from a vehicle to each connected trailer. This line is preferably routed through 20 the standard electrical/hydraulic coupling between trucks and trailers. Alternatively, wireless radio frequency transceivers may be used instead of this type of physical line.

Additionally, the hubodometer may include a modem 16 which is adapted for transmitting information relating to the distances travelled by a vehicle (and other 25 relevant information) to a remote entity (such as a billing centre) adapted to convert 14 the transmitted information into road user charge billing information that can be levied against an owner or operator of a vehicle. Such transmissions may be made by a variety of different network services including digital wireless or cellular technologies, such as Code Division Multiple Access (CDMA) or General Packet 5 Radio Services (GPRS).

This remote entity may in some instances manage the payment of road user charges on behalf of a vehicle operator to guarantee that the vehicle operator will always have a credit balance. Distance travelled information may be transmitted relatively frequently to the remote entity who can in turn purchase road user charge 10 credit as required by a vehicle on demand. This will allow a lower average credit road user charge balance to be maintained for a vehicle, as this balance is checked more frequently against distance travelled.

The components required to perform the method according to the present invention may be securely stored to prevent unauthorised tampering. For example, 15 components including GPRS modem 16, GPS receiver (such as an antennae for receiving signals transmitted by the GPS transmitter 14) and (optionally) the internal motion sensor 17 (which formed as an accelerometer) may be located within the electronic hubodometer 10. Associated with internal motion detector 17 is a power supply (such as a back-up rechargeable battery) which is adapted to 20 provide power to the controller independently of the vehicle's main power supply. Physically surrounding the electronic hubodometer 10 is an integrally moulded plastic housing 18. In the event of unauthorised tampering with the hubodometer 10 it will be readily noticeable upon inspection of the housing 18. Furthermore, if the housing 18 is broken a sensor may be adapted to detect this and send 25 instructions to a processing means to corrupt the internal data making the hubodometer 10 unusable and the data stored therein tamperproof.

The operation of each of the components of the hubodometer 10 is controlled by controller 19 which incorporates processing means adapted to execute computer software configured to perform the method of the present invention. Such software may be embodied by computer executable instructions stored on a computer 5 readable medium.

In some embodiments the external motion sensor (11) may also be provided with a wireless data link to the controller (19). Well known radio frequency signalling schemes and protocols may be used to implement such as a wireless link as should be appreciated by those skilled in the art. However, in other embodiments 10 a physical wire or line may be employed to implement this connection if required in other embodiments.

In some instances the rotation or external motion sensor (11) may be implemented with inductive power generation system. This stored energy may be used to power the external sensor (11) which need necessarily only operate when the vehicle 15 involved is moving.

The present invention may provide many potential advantages over the prior art.

The provision of a method calibrating tachometric pulses using GPS positional data in order to accurately determine the distance travelled by a vehicle is of advantage.

The provision of secure and tamper evident components which are adapted to 20 perform the above method are of advantage.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof.

A changing magnetic field may be experienced by an external motion sensor 25 mounted on a wheel, allowing an electrical current to be induced within a conductor 16 associated with the sensor. Energy sourced from this induced current may also be preferably stored in a battery or other similar energy storage system.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof as defined in the appended claims. 17

Claims (27)

WHAT WE CLAIM IS:

1. A method of determining distance travelled by a moving object, the object including means for outputting a first distance signal indicative of distance travelled, including the steps of: i) receiving the first distance signal, ii) receiving a second distance signal generated independently of the first distance signal, iii) determining a distance calculation coefficient based upon the second distance signal, and iv) using the first distance signal and the distance calculation coefficient to determine distance travelled in a predetermined period, and v) transmitting the distance determined to a remote entity.

2. A method as claimed in claim 1, including means for receiving from said remote entity an indication of a usage charge balance associated with the moving object.

3. A method as claimed in claim 1 or 2, wherein the moving object includes a rotating means in contact with the ground, and the first distance signal provides an indication of the number of rotations of the rotating means.

4. A method as claimed in any previous claim, wherein the second distance signal provides an indication of position at predetermined times.

5. A method as claimed in claim 4, wherein the second distance signal is generated by a global positioning system. intellectual Property Office of N.Z. 19 OCT 2006 18 received

6. A method as claimed in any previous claim, wherein the first distance signal includes a series of pulses, where each rotation of a rotating means corresponds to one or more pulses.

7. A method as claimed in claim 6, wherein the distance calculation coefficient is determined by summing pulses from the first distance signal which are received during the time between two or more indications of position provided by the second distance signal, and dividing the distance between the two or more indications of position by the sum of the pulses.

8. A method as claimed in claims 6 or 7, wherein the distance travelled in a predetermined period is calculated by multiplying the number of pulses in the first distance signal during the predetermined period by the distance calculation coefficient.

9. A method as claimed in any previous claim, wherein the distance calculation coefficient is determined over a predetermined distance travelled by the moving object, wherein the predetermined distance is calculated based upon the second distance signal.

10. A method as claimed in claim 9, wherein an initial estimate of the distance calculation coefficient is determined over a first distance.

11. A method as claimed in claim 10, wherein the initial estimate of the distance calculation coefficient is substituted by a revised value which is determined over a second distance, said second distance being greater then the first distance.

12. A method as claimed in claim 11, wherein the initial estimate is only substituted once a predetermined number of revised values of distance Intellectual Proi eiiectual Property Office of N.Z. 19 OCT 2006 19 calculation coefficient, each determined over respective said second distances, are within a predetermined percentage of one another.

A method as claimed in any one of claims 9 to 12, wherein if the second distance signal is unavailable, the distance travelled in a predetermined time period is calculated by multiplying the number of pulses in the first distance signal during the predetermined period by a predetermined distance calculation coefficient.

A method as claimed in any previous claim, wherein if the first and second distance signals are unavailable a third distance signal detects whether the object is moving and records an indication thereof.

A method as claimed in claim 14, wherein the third distance signal is generated by an accelerometer positioned in or on the object.

An electronic hubodometer incorporating means to implement the method as claimed in claim 1.

An electronic hubodometer as claimed in claim 16, which includes a control means adapted to execute a computer program which carries out the method according to any one of claims 1 to 15.

A system for determining distance travelled by a moving object by the method as claimed in claim 1 which includes, an electronic hubodometer, means for generating said first signal, and means for generating said second signal. intellectual Property Office of N.Z. 19 OCT 2006 20 received

19. A system as claimed in claim 18 which also includes transmission means for transmitting said distance determined to a remote entity.

20. A system as claimed in claim 19 wherein the transmission means is a modem.

21. A system as claimed in claim 19 or 20 wherein the transmission means also sends tamper detect information to a remote entity.

22. A system as claimed in any one of claims 18 to 21 wherein the means for generating said first signal includes a rotation sensor which incorporates and inductive energy generator, and an energy storage means, and a rotation detection transducer.

23. A system as claimed in claim 22 wherein the inductive energy generator of the rotation sensor is adapted to supply energy to the energy storage means when the object for which a distance is to be determined is moving.

24. A system as claimed in any one of claims 18 to 23 wherein the hubometer includes an internal motion sensor.

25. A system as claimed in any one of claims 18 to 24 wherein the hubometer includes an independent power supply.

26. A system for determining a distance substantially as herein described with reference to and as illustrated by the accompanying drawings and/or examples.

27. An electronic hubodometer substantially as herein described with reference to and as illustrated by the accompanying drawings and/or examples. Intellectual Property Office of N.Z. 19 OCT 2006 received A method of determining distance travelled by a moving object substantially as herein described with reference to and as illustrated by the accompanying drawings and/or examples. E-ROAD LIMITED intellectual Property Offio® of N.i 19 OCT 2006 received