While machine learning models are powering more and more everyday devices, there is a growing need for explaining them. This especially applies to the use of deep reinforcement learning in solutions that require security, such as vehicle motion planning. In this paper, we propose a method for understanding what the RL agent’s decision is based on. The method relies on conducting a statistical analysis on a massive set of state-decisions samples. It indicates which input features have an impact on the agent’s decision and the relationships between the decisions, the significance of the input features, and their values. The method allows us to determine whether the process of making a decision by the agent is coherent with human intuition and what contradicts it. We applied the proposed method to the RL motion planning agent which is supposed to drive a vehicle safely and efficiently on a highway. We find out that making such an analysis allows for a better understanding of the agent’s decisions, inspecting its behavior, debugging the ANN model, and verifying the correctness of the input values, which increases its credibility.
Testing and evaluation of an automotive perception system is a complicated task which requires special equipment and infrastructure. To compute key performance indicators and compare the results with the real-world situation, some additional sensors and manual data labelling are often required. In this article, we propose a different approach, which is based on a UAV equipped with a 4K camera flying above the test track. Thanks to the synchronisation of the sensors between the tested vehicle and the UAV, it is possible to precisely determine the positions of the objects around the car and correlate them with the perception system readings. The performed experiments indicate that this approach could be an interesting alternative to the existing evaluation solutions.
While machine learning models are powering more and more everyday devices, there is a growing need for explaining them. This especially applies to the use of Deep Reinforcement Learning in solutions that require security, such as vehicle motion planning. In this paper, we propose a method of understanding what the RL agent’s decision is based on. The method relies on conducting statistical analysis on a massive set of state-decisions samples. It indicates which input features have an impact on the agent’s decision and the relationships between decisions, the significance of the input features, and their values. The method allows us for determining whether the process of making a decision by the agent is coherent with human intuition and what contradicts it. We applied the proposed method to the RL motion planning agent which is supposed to drive a vehicle safely and efficiently on a highway. We find out that making such analysis allows for a better understanding agent’s decisions, inspecting its behavior, debugging the ANN model, and verifying the correctness of input values, which increases its credibility.