Acquiring and logging data is one of the main tasks in road testing or development. If a single tool is used to log different sources, the result is a hodgepodge of different data loggers in the vehicle. CANape Logging is the solution for the task of logging ADAS logs in the vehicle. Now only one data logger is needed to fulfill all requirements.
Developing complex systems such as driver assistance systems is a major challenge for all parties involved. Many different ADAS sensors and control units are brought together in the vehicle. For analyzing system behavior and re-simulation, among many other reasons, recording data in the vehicle is critical. Suppliers are completely free to choose their tool chains. However, when several suppliers’ products are now gathered in one vehicle, it is no longer a matter of individuals, but of the overall solution: a tool chain that records and stores all data sources simultaneously. What do these challenges and the details of their solutions look like?
1 Current status of the vehicle
Acquiring and recording data is a major task in road testing or development. If different sources are collected using a single tool, the result is an accumulation of different data loggers in the vehicle. There are many challenges with such a solution.
Common start, stop and trigger of multiple data loggers and temporal synchronization of measurement data.
Increased space requirements and power for many data loggers.
The driver needs to know all systems, for example, to read measurement data from different data loggers.
2 Requirements for data loggers
ADAS applications mainly involve data from radar, video and LiDAR sensors. Depending on the manufacturer and sensor type, they transmit data via classic bus, Ethernet and video interfaces. Ground truth data, such as position from RTK (Real Time Kinematics) systems or video from contextual cameras, are needed to better assess vehicle conditions. In addition to XCP, other protocols such as SOME/IP and DoIP are used to record ECU data.
Currently, each vehicle generates a few hundred megabytes of data per second. However, future sensors will provide much more data. In this regard, only scalable solutions can help protect investments in measurement technology. Very different types of data are also recorded. The data logger has a removable storage unit with a size of 10 TB, which offers the advantage of fast setup and removal times. This significantly reduces vehicle downtime for data transfer compared to transfer via WiFi/Ethernet. How do you overcome the problem of multiple data loggers in a vehicle? The answer is simple: all requirements can be met with just one logger, and Vector has developed the “Smart Log” series for just this purpose.
CANape logs can be used to acquire all bus, sensor and ECU data (Figure 1). vector’s network interface provides access to CAN / CAN FD, Automotive Ethernet and Flex-Ray. all raw and debug data from sensors, and of course all ECU internal values, are collected with the Vector VX1000 product family. CANape logs are scalable in many ways. If more memory or ports are needed, the existing setup can be extended to include additional industrial computers in the vehicle. Data is logged using the ASAM standard MDF. In addition to signal and bus messages, video, raw sensor data, description files and other metadata can be integrated. Thus, the MDF file contains everything needed for analysis or re-simulation. If the written storage medium is full, it can be replaced with an empty storage medium in just a few steps (Figure 2). The vehicle is quickly back on the road while the data from the storage media is transferred to the network.
3 Process Reliability and Adaptability
After installing the CANape log in the vehicle and connecting all components, the connection to CANape is established via Ethernet. While the application engineer is working in CANape, all data is concentrated in the CANape log. After successful setup, CANape is disconnected from the CANape Log and the logger continues to process the configuration autonomously. There is no room for transmission errors between the patching tool and the logger. While driving, the driver uses the app on his smartphone or tablet to view all necessary information or to trigger actions such as start and stop. If configuration changes are necessary, CANape will always reconnect to the CANape log. If parameters in the ECU or measurement configuration need to be adjusted, there is no need to change the wiring in the vehicle. This ensures efficient and process-safe work.
4 Example of ADAS logging explained
