Aftermarket Telematics Ignition Detection via Vibration and Voltage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Aftermarket telematics control units (TCUs) in vehicles often lack access to proprietary codes that indicate the operation of the ignition switch, hindering their ability to determine the vehicle's run state, which is crucial for power management and telematics services.
Innovation Solution
An aftermarket TCU device employs accelerometers to detect vibrations and evaluates battery voltage to determine if the vehicle is in a run mode, using a method that distinguishes between engine operation and external forces, and implements conditional key states to confirm ignition switch operations without relying on an ignition sense wire.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of information
If an aftermarket TCU couples to a diagnostic port to access proprietary codes, then access to ignition switch operation codes is improved, but device complexity and installation complexity increase
Solution Approach 1:
The patent extracts the essential detection function from the complex diagnostic port coupling system. By using accelerometers and voltage sensors that can be connected through simpler interfaces, the invention separates the core detection capability from the proprietary code dependency, thereby reducing installation complexity while maintaining the ability to detect ignition state
Solution Approach 2:
The patent introduces intermediary sensors (accelerometers and voltage sensors) that mediate between the physical ignition events and the TCU detection system. These intermediaries translate mechanical vibrations and electrical voltage changes into detectable signals, eliminating the need for direct access to proprietary ignition codes through complex diagnostic port coupling
2Use of energy by moving object
If the TCU enters sleep mode to reduce energy usage, then power consumption is reduced, but detection response time increases
Solution Approach 1:
The patent implements preliminary action by having sensors continuously monitor for ignition events even when the TCU is in sleep mode. The accelerometers and voltage sensors remain active or can be quickly activated, detecting ignition events before the TCU fully wakes up, thereby reducing the effective detection response time while maintaining energy savings
Solution Approach 2:
The patent employs periodic action through scheduled wake-up intervals and periodic sensor sampling. The TCU periodically wakes up to process data and then returns to sleep mode, creating a rhythm of activity and rest that balances energy consumption with detection responsiveness. This periodic operation allows the system to meet detection requirements while minimizing overall power usage
3Measurement precision
If vibration detection threshold is lowered to detect ignition events, then detection sensitivity is improved, but false positives from external forces increase
Solution Approach 1:
The patent merges multiple detection methods by combining accelerometer-based vibration detection with voltage sensor monitoring. By requiring both vibration patterns and corresponding voltage changes to confirm an ignition event, the system achieves high detection sensitivity while filtering out false positives from external forces that would not produce the characteristic combined signal pattern
Solution Approach 2:
The patent implements feedback mechanisms where the TCU analyzes the relationship between vibration signals and voltage signals in real-time. When vibration detection threshold is lowered, the feedback loop cross-validates these signals with voltage measurements, confirming whether detected vibrations correspond to actual ignition events or external disturbances, thereby maintaining reliability despite increased sensitivity
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 solution enables reliable detection of the vehicle's ignition state without an ignition sense wire, simplifying installation and reducing false positives, thereby ensuring efficient power management and telematics services.
Implementation Method 1
An aftermarket TCU device that includes accelerometers, runs a computer program that processes the steps of a method for detecting that an operator has operated the ignition device. In an aspect, the method may detect vibration from the accelerometers
Implementation Method 2
The method evaluates battery voltage and may determine that although a battery's nominal voltage is 12 volts, if the voltage across the poles of the vehicle's battery drops below 12 volts and then rises to a level above 12 V, the vehicle's engine is running
Data Source
AI summary
In telematics device mounted to a vehicle, an auxiliary processor detects an interrupt from an accelerometer and forwards the interrupt to a main processor—the interrupt wakes up the processor from a sleep mode. The main processor may then compare vehicle voltage and/or a value for a speed parameter to predetermined criteria to determine whether the interrupt was a false positive or if the accelerometer missed a detection of a user cranking up the vehicle. The main processor may also enter a conditional state if monitored information meets a minimum threshold. During the conditional state, the processor may operate according to rules for a current operational state and also according to rules for a changed state. The threshold for deeming a changed operational state is higher than for entering a conditional state to evaluate whether a change of operational state (i.e., on to off, or off to on) occurred.