Robotics applications have hard time constraints and heavy computational burdens that can greatly benefit from domain-specific hardware accelerators. For the latency-critical problem of robot motion planning and control, there exists a performance gap of at least an order of magnitude between joint actuator response rates and state-of-the-art software solutions. Hardware acceleration can close this gap, but it is essential to define automated hardware design flows to keep the design process agile as applications and robot platforms evolve. To address this challenge, we introduce robomorphic computing: a methodology to transform robot morphology into a customized hardware accelerator morphology. We (i) present this design methodology, using robot topology and structure to exploit parallelism and matrix sparsity patterns in accelerator hardware; (ii) use the methodology to generate a parameterized accelerator design for the gradient of rigid body dynamics, a key kernel in motion planning; (iii) evaluate FPGA and synthesized ASIC implementations of this accelerator for an industrial manipulator robot; and (iv) describe how the design can be automatically customized for other robot models. Our FPGA accelerator achieves speedups of 8× and 86× over CPU and GPU when executing a single dynamics gradient computation. It maintains speedups of 1.9× to 2.9× over CPU and GPU, including computation and I/O round-trip latency, when deployed as a coprocessor to a host CPU for processing multiple dynamics gradient computations. ASIC synthesis indicates an additional 7.2× speedup for single computation latency. We describe how this principled approach generalizes to more complex robot platforms, such as quadrupeds and humanoids, as well as to other computational kernels in robotics, outlining a path forward for future robomorphic computing accelerators.
The scale of Internet-connected systems has increased considerably, and these systems are being exposed to cyber attacks more than ever. The complexity and dynamics of cyber attacks require protecting mechanisms to be responsive, adaptive, and large-scale. Machine learning, or more specifically deep reinforcement learning (DRL), methods have been proposed widely to address these issues. By incorporating deep learning into traditional RL, DRL is highly capable of solving complex, dynamic, and especially high-dimensional cyber defense problems. This paper presents a survey of DRL approaches developed for cyber security. We touch on different vital aspects, including DRL-based security methods for cyber-physical systems, autonomous intrusion detection techniques, and multi-agent DRL-based game theory simulations for defense strategies against cyber attacks. Extensive discussions and future research directions on DRL-based cyber security are also given. We expect that this comprehensive review provides the foundations for and facilitates future studies on exploring the potential of emerging DRL to cope with increasingly complex cyber security problems.