Speed detection for a tachograph system
First Claim
1. A method of operating a tachograph system comprising a plurality of sensors and a computation unit configured to detect and store at least a speed as a piece of registration-relevant information for the tachograph system, the method comprising:
- detecting a signal from each of the plural sensors for determining the speed;
checking the detected signals for plausibility by comparing the detected signals;
storing a sensor-related error message if the detected signals differ more than a predetermined amount;
checking one of the plural sensors that is a pilot sensor and has an associated pilot function for plausibility using the detected signals from the other plural sensors;
flagging the pilot sensor as erroneous when the signals supplied by the other plural sensors differ from one another within a preset limit and a signal from the pilot sensor differs beyond the preset limit;
ascertaining the speed based on the plausibility-checked signals from a majority of the plural sensors when the pilot signal is flagged as erroneous, wherein the signals from the majority of the plural sensors differ from each other within a preset limit; and
storing an error message when the pilot signal is flagged as erroneous.
1 Assignment
0 Petitions
Accused Products
Abstract
System and method for detecting and storing at least speed as an information relevant for resignation for a tachograph system. to provide a tamperproof tachograph system offering a high degree of security. An arithmetic unit detects signals for determining the speed from at least two independent sensors and compares them with each other and stores a sensor-related error message if the signals deviate significantly from each other. The signals of at least three independent sensors are compared with each other in the arithmetic unit and are checked for their plausibility by excluding any signals that significantly deviate from a plurality of signals and determining the speed of the vehicle to be stored only using one or more of those signals that deviate from each other only within defined limits.
30 Citations
15 Claims
-
1. A method of operating a tachograph system comprising a plurality of sensors and a computation unit configured to detect and store at least a speed as a piece of registration-relevant information for the tachograph system, the method comprising:
-
detecting a signal from each of the plural sensors for determining the speed; checking the detected signals for plausibility by comparing the detected signals; storing a sensor-related error message if the detected signals differ more than a predetermined amount; checking one of the plural sensors that is a pilot sensor and has an associated pilot function for plausibility using the detected signals from the other plural sensors; flagging the pilot sensor as erroneous when the signals supplied by the other plural sensors differ from one another within a preset limit and a signal from the pilot sensor differs beyond the preset limit; ascertaining the speed based on the plausibility-checked signals from a majority of the plural sensors when the pilot signal is flagged as erroneous, wherein the signals from the majority of the plural sensors differ from each other within a preset limit; and storing an error message when the pilot signal is flagged as erroneous. - View Dependent Claims (2)
-
-
3. A tachograph system for capturing registration-relevant vehicle data comprising:
-
a plurality of sensors configured to detect a speed of the vehicle and output a signal representing the detected speed, wherein one of the sensors is a tachometer on an output side of a vehicle gearbox configured for speed detection; a computation unit coupled to the tachometer and the plural sensors configured to compare the signals output by the tachometer and the plural sensors and check the signal from the tachometer for plausibility using the plural sensors; a memory for storing at least the speed as a piece of registration-relevant information, wherein the computation unit is configured to; exclude erroneous signals and ascertain the speed using only those signals supplied by the sensors which are within particular limit values and the ascertained speed is determined using signals from a majority of the plural sensors. - View Dependent Claims (4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. A method of operating a tachograph system comprising:
-
receiving a plurality of data from a first source; storing the received plural data with respective time stamps; storing sensor data from a plurality of sensors with respective time stamps; checking the stored received data for plausibility by comparing them to the stored data from the plural sensors; checking the first source that is a pilot sensor and has an associated pilot function for plausibility using the stored data from a majority of the plural sensors; calculating at least one of distance and speed based on the plausibility-checked signals for each of the sensor data and received data; comparing the at least one of the calculated distance and speed, wherein the steps of calculating and comparing are repeated when the compared calculated distance and speed are within prescribed limits and wherein an error message is generated and stored when the compared at least one of the calculated distance and speed are not within the prescribed limits. - View Dependent Claims (13, 14, 15)
-
Specification