Sensor Trigger Hub for GPS PPS Synchronization Across Vehicle Sensors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing systems for autonomous and semi-autonomous vehicles face challenges in achieving reliable time synchronization among diverse sensors and devices, leading to uncertainties in data capture and synchronization, particularly due to varying timing signal requirements and electrical load issues with GPS PPS signals.
Innovation Solution
A sensor trigger hub system that receives a GPS PPS signal and generates adjustable output signals to accommodate different sensor requirements, using a programmable multi-channel output system to adjust frequency, phase, and shape of the trigger signals, ensuring all sensors can operate in sync without modifying existing devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If GPS PPS signal is used to trigger sensors, then time synchronization is provided, but electrical load problems cause trigger pulse shape changes leading to false triggering
Solution Approach 1:
The patent introduces an intermediary device (trigger hub or signal conditioner) between the GPS PPS signal source and the sensors. This intermediary buffers the trigger signals, isolating the sensors from electrical load variations and preventing false triggering while maintaining accurate time synchronization.
Solution Approach 2:
The patent creates clean copies of the GPS PPS trigger signal using buffer circuits or signal conditioning hardware. These copied signals are distributed to multiple sensors without being affected by the original signal's electrical load problems, ensuring consistent trigger pulse shapes for reliable sensor activation.
2Adaptability or versatility
If multiple sensors with different timing requirements are connected to GPS PPS, then comprehensive sensing is achieved, but electrical load increases causing trigger pulse distortion
Solution Approach 1:
The patent segments the trigger signal distribution by providing individual buffered trigger outputs to each sensor or sensor group. This segmentation isolates each sensor's timing requirements while maintaining a common synchronized reference, allowing diverse sensors to operate reliably without mutual interference.
Solution Approach 2:
The patent creates a universal trigger distribution system that can accommodate multiple sensor types with different timing requirements. The system provides a common synchronized trigger source that can be individually configured for each sensor type, enabling one system to serve multiple functions while maintaining signal integrity.
3Reliability
If PTP protocol is used for clock synchronization, then networked devices can synchronize clocks, but sensors lacking PTP functionality cannot be synchronized
Solution Approach 1:
The patent uses a trigger hub as an intermediary that receives PTP-synchronized timing information and converts it into simple trigger pulses for sensors that cannot process PTP. This intermediary bridges the gap between sophisticated networked devices requiring PTP and simple sensors accepting only basic trigger signals.
Solution Approach 2:
Instead of requiring sensors to support PTP protocol, the patent inverts the approach by having the central system perform PTP synchronization and then distribute simplified trigger signals to all sensors. This reversal allows high-precision synchronization at the network level while maintaining simplicity at the sensor level.
Data Source
AI summary
A system and method, optionally implemented in a hardware circuitry, to receive a global positioning system pulse per second, GPS PPS, signal generated by a GPS receiver in a vehicle having a plurality of sensors; monitor the GPS PPS signal for an indication of a presence and a frequency of the GPS PPS signal within a predetermined threshold; generate a generated PPS signal synchronized with the GPS PPS signal; generate, based on an input of the generated PPS signal, a plurality of trigger signals, each of the generated plurality of trigger signals being selectively programmatically adjustable in at least one of a frequency and a phase, the selectively adjustability of each of the generated plurality of trigger signals being independent of the other generated plurality of trigger signals; and transmit at least one of the generated plurality of trigger signals to one or more of the sensors.