SiL
SiL: the first step in the real world
SiL testing involves the evaluation and validation of software components within a simulated environment before their integration into the actual hardware. This methodology allows developers to thoroughly assess the performance, functionality, and reliability of software elements in a controlled virtual setting.
Trying to empower the performance offered by our Corner Brake Actuators, we decided to study and implement a custom ABS logic.
This being the case, we developed three different ABS control algorithms, progressively increasing the level of complexity involved.
Then, the effect of each one was assessed on a virtual environment (M42 Hardware and Human in the Loop steering bench) in different cases.
Longitudinal and combined braking conditions, in both low and optimal road-tire adherence circumstances, were examined.
# Direct use of production-level software
# Complete traceability of both high and low-level requirements
# Validation of the specification framework at HW level
# FuSa/SOTIF assessment at SW level
FuSa: Functional Safety
SOTIF: Safety Of The Intended Functionality
Case study: ABS logic development
Aim of the activity
# Comparison of three different ABS algorithms
Method
# Assessment on a virtual environment with SiL approach
Results
# Advantages and drawbacks of each controller was tested in different conditions
- Longitudinal braking (high ad low adherence)
- Combined braking (high ad low adherence)
Case study: Proprietary ABS logic research
Vehicle model
Multi-degree vehicle model developed in ADAMS environment and implemented in Vi-grade CRT to be co-simulated with Matlab-Simulink
Controls in SiL
# State estimator with an Unscented Kalman Filter
# Electronic Stability Control (ESC)
# Electronic Brake-force Distribution (EBD)
# ABS
Case study: autonomous vehicles
# At limit handling condition autonomous driving controller
# Trajectory generation
- Minimum curvature algorithm
# Sideslip angle estimation
- Artificial Neural Network (ANN)
- Unscented Kalman Filter (UKF)
- Experimental test
# Hierarchical Robot Controller
- High-level Non-linear Model Predictive Controller
- Low-level Non-linear Model Predictive Controller
# High-level NMPC
- Computes vehicle velocity profile for the long prediction horizon
- Feed the start braking point to the low-level controller
- High-fidelity 7 DOF vehicle model
# Low-level NMPC
- Determines vehicle action for the short prediction horizon
- Simple point-mass vehicle model