Time Synchronization
Overview
SENSR is designed for real-time data processing with LiDARs, including setups across distributed systems. While most use cases do not require highly accurate time synchronization, it can be implemented for applications that demand high precision, such as autonomous driving. This article outlines time synchronization strategies for the various components of the system.
The system is made of the following components:
- Business logic layer consuming SENSR's Master node output
- Master node merging multiple Algo nodes
- Algo nodes fusing data from multiple LiDARs
- LiDARs scanning the area of interest at a set frequency
Time Synchronization
Synchronization at hosts level
SENSR and its components use the system clock of the underlying operating system. Therefore, synchronizing the clocks on all hosts where the software is running (including the Business logic, Master, and Algo node hosts) will ensure time synchronization. The NTP or PTP protocol is recommended for this purpose.
LiDARs synchronization
Some LiDAR models support time synchronization using the PTP protocol. This is typically configured through the sensor's web interface or the manufacturer's provided software.
For detailed instructions, please consult your LiDAR manufacturer's manual or contact our support team.
Once the LiDARs are synchronized to a common time source, you must enable SENSR to use their timestamps. In the LiDAR Driver Configuration, go to Advanced Configuration and check the Use lidar timestamp option. This ensures that SENSR accurately aligns frames from different sensors, preventing data offsets.
Note: This process synchronizes the LiDAR's internal clock but does not align the precise firing times of the lasers. Minor distortion may still occur for objects moving at very high speeds.
Verification
You can verify the time difference between the Master Node and the Algo Nodes in two ways:
- In Project Setup mode, hover your mouse over the latency value (** ms) next to the Algo Node's name.
- In Runtime mode, open the Window > Connection Monitor to see detailed connection and timing information.