DE102007024692A1 - Method for determining mileage range of vehicle, involves determining location data by global positioning system receiver with measuring frequency - Google Patents

Abstract

The method involves determining a location data by a Global positioning system receiver (3) with a masuring frequency. The location data is sent to an evaluation unit (2). The evaluation unit evaluates the number of satellite signals which are recorded. The location data is evaluated in two dimension and three-dimension forms. The determined distance is transmitted to a center by a Global system for mobile communication module (4). An independent claim is also included for a device for determining the mileage range of a vehicle.

Description

The The invention relates to a method and a device for determining the distance traveled by a motor vehicle.

Usually becomes the distance traveled of a motor vehicle determined by an odometer, for example, evaluates the signals of a wheel speed sensor. Depending on the sensor used or investigation are the determined routes with measurement errors afflicted, the permitted Deviation from odometer is +/- 4%.

It However, applications are known where the distance traveled without data from the vehicle sensor system must or can be determined for example, for reasons of security against manipulation.

• – Erfassung des Beförderungsbeginns jeder beförderten Person durch Registrierung eines Merkmals zur persönlichen Identifizierung der Person sowie des aktuellen Datums und der Uhrzeit,
• – Erfassung jeder gefahrenen Teilstrecke,
• – Erfassung des Beförderungsendes jeder Person durch Registrierung des aktuellen Datums und der Uhrzeit und
• – Verarbeitung der erfassten Daten und Ausgabe am Zielort der Beförderungsfahrt, wobei in einer einfachen Ausgestaltung des Verfahrens gefahrene Teilstrecken durch Registrierung von durch satellitengestützte Positionierungssysteme bereitgestellten Daten am Beförderungsbeginn und Beförderungsende jeder Person erfasst werden. Die Verwendung von Daten satellitengestützter Positionierungssysteme ist besonders vorteilhaft, weil sie über die bloße Entfernungsbestimmung hinaus sowohl die exakte Bestimmung jedes einzelnen Start- und Zielortes einer beförderten Person als auch hochgenaue Zeiterfassung gestattet.

From the DE 10 2005 010 251 A1 is known a method for the personal registration of travel costs, comprising the steps

• - recording the start of the journey of each person carried by registering a feature for the personal identification of the person and the current date and time;
• - recording each driven leg,
• - recording the end of each person's journey by registering the current date and time and
• Processing of the collected data and output at the destination of the transport journey, whereby sections traveled in a simple embodiment of the method are detected by registration of data provided by satellite-based positioning systems at the beginning and end of each person's transport. The use of data from satellite-based positioning systems is particularly advantageous because, in addition to mere distance determination, it permits both the exact determination of each individual start and destination location of a person being transported and also highly accurate time recording.

From the DE 100 43 311 A1 A method for tamper-proof toll collection on toll roads is known, which also uses GPS data to determine the path length.

Of the Invention is the technical problem underlying a method and a device for determining the traveled path length of a motor vehicle with regard to the accuracy of the determined To improve path length.

The Solution of the technical problem results from the objects with the features of claims 1 and 8. Further advantageous Embodiments of the invention will become apparent from the dependent claims.

For this includes the device for determining the traveled Path length of a motor vehicle at least one GPS receiver and an evaluation unit, wherein the GPS receiver with a Measurement frequency f location data and to the evaluation unit delivers, taking from the geometric distance between two locations a distance traveled in the evaluation unit calculated and integrated, whereby the evaluation unit evaluates, how many satellite signals are detected, with one receiving position with more than n satellites, with n ≥ 4, the location data be evaluated three-dimensionally and in a receiving position with less than n satellites are evaluated two-dimensionally. there is exploited that in the conventional method only is calculated two-dimensionally, which leads to slopes and gradients are not taken into account, which ever to terrain can lead to significant deviations. By the consideration of altitude information can This error can be almost eliminated. Since n = 4 is the minimum number is there still measurement errors in the weight, so preferably n ≥ 5 or n ≥ 6 is selected. there It should be noted that the term GPS is generically referred to as satellite-based Positioning system to be understood.

In In another preferred embodiment, the measuring frequency of the GPS receiver depending on the vehicle speed and / or a detected cornering changed. Thereby the deviation can be further reduced. It is true that at lower speeds the measuring frequency is reduced. This results in deviations in the individual measurements, not existing movements suggest less weight. When cornering however, the measurement frequency should be increased so that the curve is better measured. The determination that a cornering is present, for example, directly from the direction data of the GPS signals take place. Alternatively or supportive also used the data of a digital road map become. Similarly, the speed can be derived directly from the GPS data become. The adjustment of the measuring frequency can be discrete, for example in four stages, or continuously. The advantage of Discrete adaptation is that the computational effort for the Evaluation unit is low, the deviation from the continuous adaptation is negligibly small. The adjustment of the measurement frequency is also inventive and innovative can also be used in systems that are exclusively two-dimensional measure up.

In a further preferred embodiment, the device comprises a GSM module, wherein the determined path length is transmitted to a control center by means of the GSM module and / or a start position determination by means of the GPS receiver is supported by means of received data of the GSM module. The transmission of the path length or additionally further data is preferably via SMS and / or GPRS. The support for starting position determination is based on an evaluation of the data on the reception position of the GSM data. For example, from these data, a country code can be removed, based on which the search process for the GPS receiver can be accelerated, for example, because previously the vehicle was transported by a car train from Germany to Italy. The acceleration of the determination of the starting position, in turn, reduces the error in determining the path length.

In In another preferred embodiment, the evaluation unit transmits at least one operating signal of the motor vehicle, wherein a Weglängenermittlung depending on the operating signal carried out or not carried out. Preferably, the operation signal "ignition on" is KL15, so that only a path length calculation takes place when the Ignition is switched on. This will be effective suppressed a path length calculation, for example the motor vehicle is towed or by means of semi-trailer, Train or ship is transported.

In Another preferred embodiment, the device a ground and an operating voltage connection, so that the Device also with the terminals KL30 and KL31 of the motor vehicle can be connected. It can also be provided that the Device via its own power supply, for example in the form of a backup battery.

In Another preferred embodiment, the device an input unit via which an occasion of a carried out, for example "private trip", "business trip" or "ride apartment / work". The input can be, for example, by voice command or via each assigned Button. Preferably, however, the input is made via a selector switch, for example, with the different positions depending on the cause, more preferably, the selector switch when driving in a Default position is, preferably the position "private drive".

In Another preferred embodiment comprises Device a memory device in which the determined data be stored in the form of an electronic logbook, wherein there next to the path length and time and / or starting point and / or cause of the trip, etc. can be stored with.

The Invention will be described below with reference to a preferred embodiment explained in more detail. The figures show:

1 a schematic block diagram of a device for determining the distance traveled,

2 a schematic representation of a route with slope,

3 a representation of the measurement error over the gradient in% in a two-dimensional measurement,

4 a schematic representation of a cornering in the region of the turning circle of a motor vehicle,

5 a representation of the measurement error over the measurement frequency when cornering and

6 a schematic representation of a measured value distribution with existing vehicle.

In the 1 is a schematic block diagram of a device 1 for determining the traveled path length of a motor vehicle, comprising an evaluation unit 2 , a GPS receiver 3 , a GSM module 4 , a selector switch 5 , a combined GPS / GSM antenna 6 and an internal bus 7 , Furthermore, the device comprises 1 Connections for a KL15 operating signal, a KL30 power supply and ground KL31. About the GPS receiver 3 receives the device 1 Position and time signals from different satellites, via the internal bus 7 to the evaluation unit 2 be transmitted, wherein the evaluation unit 2 evaluates how many satellite signals are detected, wherein at a reception position with more than n satellites, with n ≥ 4, the location data are evaluated in three dimensions and are evaluated two-dimensionally at a receiving position with less than n satellites. The GPS receiver delivers 3 Location data with a measurement frequency f, wherein from the distance between two location data a distance traveled in the evaluation unit 2 calculated and integrated. Due to the three-dimensional evaluation of the location data, errors due to inclines and inclines are avoided, which is based on the 2 and 3 will be explained in more detail. About the GSM module 4 On the one hand, data can be transmitted, for example, to a control center (not shown) by SMS or GPRS. Furthermore, by means of received data of a GSM module 4 a starting position determination by means of the GPS receiver 3 be supported by, for example, Länderkür be evaluated by the receivable provider. Via the selector switch 5 the reason for a trip may be set, for example, whether it is a private trip, a business trip or a trip apartment / office. This travel reason can then be stored with the determined path length and other data such as time, starting point, end point in a memory, not shown in the form of an electronic logbook. The operation of the illustrated selector switch 5 is such that it has three positions, wherein the selected position is drawn to ground KL31 and the evaluation unit 2 is recognized. About the operating signal KL15, the evaluation unit 2 perform a plausibility check, whether a determination of a covered path length makes sense or not. Thus, for example, no traveled path length is calculated when the ignition is off, since then the movement of the motor vehicle indicates a towing or other transport. Furthermore, the evaluation unit fits 2 the measuring frequency of the GPS receiver 3 depending on the vehicle speed and / or a detected cornering, wherein both the vehicle speed and the passage through a curve from the GPS data is derived.

following some mathematical basics of the procedure are explained as well as the system-related measurement errors and, if necessary, their reduction described.

The calculation of the distance between two points described by two-dimensional WGS84 coordinates is done by the formula ξ = ARCCOS (SINφ a ∙ SINφ b + COSφ a ∙ cos b ∙ COS | λ b - λ a | ∙ u with φ latitude
λ Geographical length
A (φ _a , λ _a ) starting point
B (φ _b, λ _b) Endpoint
u mean earth radius (assumed value: 6371 km)
ξ Track AB in km

The Coordinates (angles) are preferably as a decimal value with Enter 5 decimal places (eg latitude of the city of Mainz: 50.00000).

If the calculation of an ARCCOS (as compulsory in most operating systems) on the conversion in Taylor series and the CPU load is too large, the following approximation formula can be used. ξ = [(φ a - φ b ) 2 + (cos (φ a + | ((φ a - φ b ∙ π / 180) / 2) | ∙ | λ a - λ b |) ∙ 111136) 2 ] 0.5 / 1000 with φ latitude
λ Geographical length
A (φ _a , λ _a ) starting point
B (φ _b, λ _b) Endpoint
ξ distance AB in km (at factor u = 6371 km for mean earth radius)

Stands then the height information available, The path can be easily determined by the theorem of Pythagoras be calculated.

• 1.) Messfehler durch Fahrten auf Steigungen/Gefälle
• 2.) Messfehler durch Kurvenfahrten
• 3.) Messfehler durch verspätetes Booten des GPS-Teils der prodim.Box
• 4.) Messfehler durch Tunnelfahrten
• 5.) Messfehler durch Ausfall der GPS-Signale/GPS-Satelliten
• 6.) Messfehler durch schwankende GPS-Genauigkeit

The system-related measurement errors in path length determinations using GPS data are:

• 1.) Measuring error due to driving on inclines / slopes
• 2.) Measuring error by cornering
• 3.) Measurement error due to late booting of the GPS part of the prodim.Box
• 4.) Measurement error due to tunnel drives
• 5.) Measurement error due to failure of the GPS signals / GPS satellites
• 6.) Measurement error due to fluctuating GPS accuracy

berechnen, wobei c) zunächst aus der zweidimensionalen Berechnung ermittelt wird.In the 2 the situation on a slope is shown schematically, where a) the distance traveled, c) the measured distance and b) the height difference between the two location data, where Δc represents the measurement error. If, however, calculated as in the invention three-dimensional, so this error does not occur and a can be with

calculate, where c) is first determined from the two-dimensional calculation.

The 3 shows the relationship between traveled gradient (or traveled gradient) and the system-related measurement error in two-dimensional calculation. In the example a ride with 10% slope is marked. The measurement error is about 5 per thousand, as can occur in mountain ranges especially slopes up to 14%. Three-dimensional location requires good GPS quality. Preferably, at least five satellites should be receivable. In the case of a reception attitude with less than five, but more than two satellites, the two-dimensional calculation is performed. The measurement error is accepted for these exceptional cases, but should be negligible over the entire mileage one day.

⇒ a/c = π/2∙√2 = 1,1107, was einen Messfehler von 11,07% entspricht.The measurement error during cornering and maneuvering in the area of the vehicle turning circle according to 4 can be estimated as follows, assuming that the next follow-up measurement After approx. 90 ° cornering:

⇒ a / c = π / 2 ∙ √2 = 1.1107, which corresponds to a measurement error of 11.07%.

Around the measurement errors during maneuvering or when cornering serpentine minimize, the measurement frequency in the default setting is preferred on 2 s. set. That means, every two seconds, the WGS84 Coordinates determined, the distance to the last determined coordinate calculated and the result added to the mileage.

5 shows the measuring error in% over the measuring frequency [in measurements per minute] when cornering. The measurement error increases sharply in areas of fewer measurements. In the range of larger measurement frequencies, the measurement error decreases. However, the measurement error does not drop arbitrarily, as another opposite effect comes to fruition, the vividly based 6 should be explained. It is assumed that the motor vehicle is at position 1 and does not move. If measurements are then carried out by the GPS receiver, the determined location data fluctuate by approximately +/- 5 m and suggest a movement. At very low speeds, therefore, a high measurement frequency leads to measurement errors. Therefore, the measurement frequency is reduced at low vehicle speeds, for example less than 20 km / h. Accordingly, the measurement frequency is increased at high speeds and cornering, and when cornering due to the usually lower speed an optimum must be sought, which is preferably at Hz.

measurement error due to tunnel trips where there is no GPS reception or temporary Failure of the GPS signals / GPS satellites are acceptable and have empirically presented as negligible.

• – Mittels der empfangenen Länderkennung durch das GSM-Modul und die dadurch mögliche Eingrenzung der möglichen Position wird die Ermittlung der Startpositionsdaten beschleunigt.
• – Die Bootsequenzen sind für beschleunigtes Einbuchen optimiert.

Measurement errors due to delayed booting of the GPS receiver are reduced by the following measures:

• By means of the received country code by the GSM module and the possible limitation of the possible position, the determination of the starting position data is accelerated.
• - The boot sequences are optimized for accelerated logging.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• DE 102005010251 A1 [0004]
• - DE 10043311 A1 [0005]

Claims (15)

Method for determining the distance traveled by a motor vehicle, by means of at least one GPS receiver and an evaluation unit, wherein the GPS receiver determines location data at a measurement frequency f and delivers it to the evaluation unit, wherein a distance covered in the evaluation unit is calculated from the distance between two location data and is integrated, characterized in that the evaluation unit ( 2 ) evaluates how many satellite signals are detected, wherein at a reception position with more than n satellites, with n ≥ 4, the location data are evaluated in three dimensions and are evaluated two-dimensionally at a receiving position with less than n satellites. Method according to claim 1, characterized in that the measuring frequency of the GPS receiver ( 3 ) is changed as a function of the vehicle speed and / or a detected cornering. Method according to claim 1 or 2, characterized in that by means of a GSM module ( 4 ) the determined path length is transmitted to a central office. Method according to one of the preceding claims, characterized in that by means of received data of a GSM module ( 4 ) a starting position determination by means of the GPS receiver ( 3 ) is supported. Method according to one of the preceding claims, characterized in that the evaluation unit ( 2 ) at least one operating signal (KL15) of the motor vehicle is transmitted, wherein in dependence of the operating signal (KL15) a path length determination is performed or not performed. Method according to one of the preceding claims, characterized in that the evaluation unit is an occasion the carried out journey is entered. A method according to claim 6, characterized in that the ascertained data stored in the form of an electric logbook become. Device for determining the traveled path length of a motor vehicle, comprising at least one GPS receiver and an evaluation unit, the GPS receiver with a measurement frequency f determines location data and supplies to the evaluation unit, wherein calculated from the distance between two locations a distance traveled in the evaluation and is integrated, characterized in that the evaluation unit ( 2 ) evaluates how many satellite signals are detected, wherein at a reception length with more than n satellites, with n ≥ 4, the location data are evaluated in three dimensions and are evaluated two-dimensionally at a reception length with less than n satellites. Apparatus according to claim 8, characterized in that the Measurement frequency f of the GPS receiver depending on the vehicle speed and / or a detected cornering changed becomes. Device according to one of claims 8 or 9, characterized in that the device is a GSM module ( 4 ), whereby by means of the GSM module ( 4 ) the determined path length is transmitted to a control center and / or by means of received data a starting position determination by means of the GPS receiver is supported. Device according to one of claims 8 to 10, characterized in that the evaluation unit ( 2 ) at least one operating signal (KL15) of the motor vehicle is transmitted, wherein as a function of the operating signal (KL15) a path length determination is performed or is not performed. Device according to one of claims 8 to 11, characterized in that the device ( 1 ) has a ground and an operating voltage connection (KL31, KL30). Device according to one of claims 8 to 12, characterized in that the device has an input unit via the one cause of a trip carried input is. Apparatus according to claim 13, characterized in that the input unit as a selector switch ( 5 ) is trained. Device according to one of claims 8 to 14, characterized in that the device ( 1 ) comprises a memory unit in which the determined data are stored in the form of an electronic logbook.