Tachograph Internal Time Synchronization via Microstep Adjustment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current tachographs face challenges in maintaining synchronous internal time with satellite navigation systems, leading to potential data recording discrepancies due to time adjustments greater than one second.
Innovation Solution
A method and device for adjusting the internal time of a tachograph using a compensation parameter that accounts for temperature and time deviations, ensuring synchronization with satellite navigation time by adjusting the real-time clock in microsteps, preventing time adjustments greater than one second.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the internal time of the tachograph is adjusted in second increments to synchronize with satellite navigation time, then the time synchronization is improved, but data recording accuracy deteriorates due to time shifts of one second or more
Solution Approach 1:
The patent changes the adjustment parameter from discrete second increments to continuous micro-step adjustments. The control device adjusts the internal time in increments of at most 0.1 seconds (100 milliseconds), rather than using whole second adjustments. This parameter change allows fine-tuned synchronization that maintains both time accuracy and data recording integrity, preventing the data gaps that occur with larger one-second shifts.
2Measurement precision
If the real-time clock is adjusted frequently to maintain synchronization with satellite navigation time, then time synchronization is improved, but system complexity increases due to continuous monitoring and adjustment mechanisms
Solution Approach 1:
The patent implements a feedback control mechanism where the control device continuously monitors the time deviation between the internal real-time clock and the satellite navigation time. Based on this feedback, the control device automatically adjusts the clock frequency or time stamps to maintain synchronization. This closed-loop feedback system achieves accurate timekeeping without requiring complex manual intervention or overly sophisticated adjustment mechanisms.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach ensures accurate data recording by maintaining the internal time of the tachograph in sync with satellite navigation time, minimizing time discrepancies to less than +/-0.1%, thereby enhancing recording accuracy.
Implementation Method 1
The compensation algorithm can consider a parameter component K 20°C for the nominal deviation of the real-time clock at 20°C and another component K temp , whose value is temperature-dependent.
Data Source
Figure 1
Figure 2
AI summary
According to a procedure for regulating the internal time of a tachograph, signals from a satellite navigation system (200) are received. By evaluating the signals, the time (tSat) specified by the satellite navigation system (200) is determined. A time deviation (Δt) of the internal time (TDTCO) of the tachograph (100) from the time (tSat) specified by the satellite navigation system (200) is determined. To align the internal time (TDTCO) of the tachograph (100) with the time (tSat) specified by the satellite navigation system (200), a component (KΔt) of a compensation parameter (Ktotal) is determined as a function of the calculated time deviation (Δt). Depending on the component (KΔt) of the compensation parameter (Ktotal), the internal time (TDTCO) of the tachograph (100) is adjusted to the time (tSat) specified by the satellite navigation system (200).