Method for storing odometer data

• US 6,768,966 B2
• Filed: 08/06/2002
• Issued: 07/27/2004
• Est. Priority Date: 08/07/2001
• Status: Expired due to Fees

• Current Assignee: Daimler AG (Mercedes-Benz Group AG)
• Original Assignee: DaimlerChrysler AG (Mercedes-Benz Group AG)
• Inventors: Rahm, Martin, Unseld, Eckard, Ohle, Jörn-Marten
• Primary Examiner(s): Barlow, John
• Assistant Examiner(s): LE, JOHN H
• Application Number:
  US10/212,148
• Publication Number:
  US 20030055599A1
• Time in Patent Office: 721 Days
• Field of Search: 702/96, 702/150, 702/158, 702/163, 702/165, 235/95, 235/96, 701/7, 701/35, 701/207, 701/213, 701/214, 377/24.1, 377/26, 340/5.22, 340/5.65, 340/426.1, 340/426.28, 340/438
• US Class Current: 702/165
• CPC Class Codes: G01C 22/02 by conversion into electric waveforms and subsequent integration, e.g. using tachometer generator G01C22/002, G01C22/004, G01C22/006 take precedence

Abstract

A method for storing odometer reading data in a vehicle having control units which are connected via a data bus. The odometer reading data, which is determined at a particular time by an odometer, is stored in a storage means of a first control unit. This provides an alternative method for tamper-proof storage of odometer reading data and, in particular, improved protection against errors during the transmission of the odometer reading data. The current odometer reading data of at least one further control unit is then stored on the data bus in a storage means. The control units transmit the odometer reading data, which is stored at a particular time, onto the data bus at specific time intervals, and a control unit accepts the odometer reading transmitted onto the data bus if that reading is higher than its stored value, and uses that value for the further counting and storage in the particular control unit.

Claims

1. A method for storing odometer reading data in a vehicle having at least two control units which are each connected via a data bus, wherein the odometer reading data, which is determined at a particular time by means of an odometers is stored in a first storage means of a first one of said at least two control units, said method comprising the steps of:

storing the current odometer reading data of at least a second one of said at least two control units on the data bus in a second storage means,

transmitting by at least one of two control units, the odometer reading data, which is stored at a particular time, onto the data bus at specific time intervals, and

accepting in one of said control units, the odometer reading transmitted onto the data bus if said reading is higher in value than a stored value, and using said value for the further counting and storage in said one control unit.

2. The method according to claim 1, wherein, before the acceptance of the odometer reading data, the odometer reading data transmitted on the data bus is checked for errors by one of said control units.

3. The method according to claim 2, wherein the odometer reading transmitted on the data bus is accepted only if a code word of the transmitted odometer reading is identical to a code word of the vehicle.

4. The method according to claim 2, wherein the odometer reading transmitted on the data bus is accepted only if a message counter of the transmitted odometer reading is incremented in a predetermined manner over a plurality of successive time periods.

5. The method according to claim 2, wherein the odometer reading which is transmitted on the data bus is accepted only if the difference between the odometer readings transmitted in a plurality of successive time periods does not exceed a predetermined distance which is characteristic of the vehicle.

6. The method according to claim 1, wherein the odometer reading which is transmitted on the data bus is accepted only if the difference between the odometer readings transmitted in a plurality of successive time periods does not exceed a predetermined distance which is characteristic of the vehicle.

7. The method according to claim 6, wherein the odometer reading transmitted on the data bus is accepted only if a code word of the transmitted odometer reading is identical to a code word of the vehicle.

8. The method according to claim 6, wherein the odometer reading transmitted on the data bus is accepted only if a message counter of the transmitted odometer reading is incremented in a predetermined manner over a plurality of successive time periods.

9. The method according to claim 1, wherein, when it is transmitted, the odometer reading data is supplemented with a code word which is uniquely defined for the vehicle, in order to ensure that the message has been transmitted by one of said units.

10. The method according to claim 9, wherein the odometer reading transmitted on the data bus is accepted only if a code word of the transmitted odometer reading is identical to a code word of the vehicle.

11. The method according to claim 9, wherein the odometer reading transmitted on the data bus is accepted only if a message counter of the transmitted odometer reading is incremented in a predetermined manner over a plurality of successive time periods.

12. The method according to claim 1, wherein, when it is transmitted, the odometer reading data is supplemented with a message counter whose value is a counter for the number of transmitted odometer reading data items of one of said control units.

13. The method according to claim 12, wherein the odometer reading transmitted on the data bus is accepted only if a message counter of the transmitted odometer reading is incremented in a predetermined manner over a plurality of successive time periods.