• Entry-level system for testing sensor fusion ECUs and domain controller with real-world data
  • Accurate HW-synchronized replay of high number of heterogeneous data streams
  • Optimized for raw sensor interfaces and bus data injection via Ethernet (TCP/UDP/IP) and CAN
  • Modular approach to fit future requirements on flexibility and scalability
  • Support for remote operation and monitoring
  • Convertible into a closed-loop HIL for scenario-based testing with low additional effort

Task

Data replay based on real-world scenarios and performed on real HW is a common method for regression tests, back-to-back tests, and release tests, as well as for HW debugging on the same level of realism as given by real test drives. Software components for sensor data fusion and activation of functions for automated driving (AD) tested in previous phases of the development process, e.g., using SIL testing in the cloud, now have to be deployed and validated on target hardware. The main objectives are evaluating the correctness of hardware interfaces for communication between real sensors and ECUs, and ensuring the performance and reliability of the target system considering high data loads and realistic timing conditions. An entry-level data replay is a perfect match when demand on flexibility and scalability of a test system is reduced, for example, when data injection into lidar or radar sensors is performed via Ethernet TCP/UDP or CAN, the focus is set on validating different versions of the same ECU, and various boardnet versions do not need to be considered. This is often the case in initial data replay projects. On entry level, a data replay system is often tailored to a specific system under test (SUT). Sensor data is mostly replayed in the same way as it was recorded or with some manipulations prior to the injection, and validation is performed in a specific replay mode of the ECU with disabled security checks.  

Challenge

During data replay tests, ADAS/AD hardware platforms must be fed with heterogeneous data streams, including raw sensor and bus data in the same manner as in the vehicle during real test drives. To be accepted by the SUT, all injected data must be replayed with high correctness and accuracy, and even in the case of an entry-level replay, this usually means the need to feed about 20 perfectly synchronized data streams into a single ECU in parallel. At all times, data replay testing is expected to be deterministic and reproducible and to exhibit realistic bus and system behavior. For many customers, setting up such an entry-level test system is just the beginning of the journey. The test system must be able to change and grow to meet future demands, and to be directly operated either on-site or in a data center via remote connection. 

Solution

An entry-level dSPACE data replay solution for the validation of sensor fusion ECUs and ADAS/AD domain controllers typically consists of a replay PC, an Environment Sensor Interface (ESI) Unit for feeding raw sensor data into the SUT, and a SCALEXIO LabBox acting as a bus data interface. Data recordings and annotations used for the replay and calculation of test results can be made available for the replay system via a local storage, or directly streamed to the replay server throughout existing cloud connection during the test execution. In both cases, RTMaps, the performance-optimized replay software executed on the PC, reads out the recorded data using appropriate file formats like MDF4, PCAP, or rosbag, and pushes the data to the ESI Unit and the SCALEXIO LabBox, the dedicated interfaces for raw and bus data injection, either directly or after manipulation (adding pixel errors, removing bus frames, etc.,). RTMaps can also be utilized to calculate key performance indicators (KPIs) after the replay by comparing the output of the SUT with provided annotations (reference data). 

Entry-level data replay validation of sensor fusion ECUs. 

The modular FPGA-based ESI Unit for the injection of raw sensor data into the validated platform can be individually equipped with a wide range of FMC modules to feed data into various interfaces of the SUT such as GMSL, FPD-Link, or MIPI CSI. The SCALEXIO LabBox real-time system maintains low-jitter real-time replay of bus data streams that transport payloads like lidar point clouds or radar object lists via UDP/IP or CAN. The SCALEXIO LabBox also establishes high-quality restbus simulation to provide the required vehicle bus data and keep the SUT at the expected operating point during the whole replay. Both the ESI Unit and the SCALEXIO LabBox are synchronized on hardware basis by generalized Precision Timing Protocol (gPTP) using the real-time clock of the SCALEXIO system as master to ensure highly accurate injection of all parallel data streams into the ADAS/AD ECU with low jitter below one ms.
 
System modularity and flexibility are at the core of the dSPACE data replay solutions to scale validation. Growing bandwidth requirements can be met by upgrading the server PC, while the type and number of sensor and bus interfaces can be increased by either expanding the existing ESI Unit and the SCALEXIO LabBox by additional FMC modules and bus boards, or by adding further ESI Units and SCALEXIO LabBoxes to the systems.  

The replay system can be remotely operated and monitored through open APIs for operation on-premises or in a data center. Another advantage is that the complete setup can be converted with minimal effort into a closed-loop HIL to perform scenario-based testing.