Deep reinforcement learning (DRL) based vehicle controllers have shown excellent performance in autonomous driving. While these controllers deliver high performance, their computational demands often require task offloading to external servers. Yet, communication delays can hinder this process, forcing reliance on a simpler local module and compromising driving efficiency. To address this, we propose a framework that integrates action smoothing and local action prediction to enhance performance while ensuring safety under offloading delays. By incorporating a smoothing term into the reinforcement learning reward and introducing a polynomial based smoothing and prediction method, our approach ensures smoother transitions and robust driving. Experiments in the CARLA simulator demonstrate improved vehicle speed, reduced center deviations, and higher track completion rates under imperfect communication conditions.

Connected Autonomous Vehicles (CAVs) are expected to enable reliable, efficient, and intelligent transportation systems. Most motion-planning algorithms for multi-agent systems implicitly assume that all vehicles/agents will execute the expected plan with a small error and evaluate their safety constraints based on this fact. This assumption, however, is hard to keep for CAVs since they may have to change their plan (e.g., to yield to another vehicle) or are forced to stop (e.g., a CAV may break down). While it is desired that a CAV never gets involved in an accident, it may be hit by other vehicles and, sometimes, preventing the accident is impossible (e.g., getting hit from behind while waiting at a red light). Responsibility-Sensitive Safety (RSS) is a set of safety rules that defines the objective of CAVs to blame, instead of safety. Thus, instead of developing a CAV algorithm that will avoid any accident, it ensures that the ego vehicle will not be blamed for any accident it is a part of. Original RSS rules, however, are hard to evaluate for merge, intersection, and unstructured road scenarios, plus RSS rules do not prevent deadlock situations among vehicles. In this article, we propose a new formulation for RSS rules that can be applied to any driving scenario. We integrate the proposed RSS rules with the CAV’s motion planning algorithm to enable cooperative driving of CAVs. We use Control Barrier Functions to enforce safety constraints and compute the energy optimal trajectory for the ego CAV. Finally, to ensure liveness, our approach detects and resolves deadlocks in a decentralized manner. We have conducted different experiments to verify that the ego CAV does not cause an accident no matter when other CAVs slow down or stop. We also showcase our deadlock detection and resolution mechanism using our simulator. Finally, we compare the average velocity and fuel consumption of vehicles when they drive autonomously with the case that they are autonomous and connected.

Exploiting model sparsity to reduce ineffectual computation is a commonly used approach to achieve energy efficiency for DNN inference accelerators. However, due to the tightly coupled crossbar structure, exploiting sparsity for ReRAM-based NN accelerator is a less explored area. Existing architectural studies on ReRAM-based NN accelerators assume that an entire crossbar array can be activated in a single cycle. However, due to inference accuracy considerations, matrix-vector computation must be conducted in a smaller granularity in practice, called Operation Unit (OU). An OU-based architecture creates a new opportunity to exploit DNN sparsity. In this paper, we propose the first practical Sparse ReRAM Engine that exploits both weight and activation sparsity. Our evaluation shows that the proposed method is effective in eliminating ineffectual computation, and delivers significant performance improvement and energy savings.

Memristor-based deep learning accelerators provide a promising solution to improve the energy efficiency of neuromorphic computing systems. However, the electrical properties and crossbar structure of memristors make these accelerators error-prone. To enable reliable memristor-based accelerators, a simulation platform is needed to precisely analyze the impact of non-ideal circuit and device properties on the inference accuracy. In this paper, we propose a flexible simulation framework, DL-RSIM, to tackle this challenge. DL-RSIM simulates the error rates of every sum-of-products computation in the memristor-based accelerator and injects the errors in the targeted TensorFlow-based neural network model. A rich set of reliability impact factors are explored by DL-RSIM, and it can be incorporated with any deep learning neural network implemented by TensorFlow. Using three representative convolutional neural networks as case studies, we show that DL-RSIM can guide chip designers to choose a reliability-friendly design option and develop reliability optimization techniques.