3D neural networks are widely used in real-world applications (e.g., AR/VR
headsets, self-driving cars). They are required to be fast and accurate;
however, limited hardware resources on edge devices make these requirements
rather challenging. Previous work processes 3D data using either voxel-based or
point-based neural networks, but both types of 3D models are not
hardware-efficient due to the large memory footprint and random memory access.
In this paper, we study 3D deep learning from the efficiency perspective. We
first systematically analyze the bottlenecks of previous 3D methods. We then
combine the best from point-based and voxel-based models together and propose a
novel hardware-efficient 3D primitive, Point-Voxel Convolution (PVConv). We
further enhance this primitive with the sparse convolution to make it more
effective in processing large (outdoor) scenes. Based on our designed 3D
primitive, we introduce 3D Neural Architecture Search (3D-NAS) to explore the
best 3D network architecture given a resource constraint. We evaluate our
proposed method on six representative benchmark datasets, achieving
state-of-the-art performance with 1.8-23.7x measured speedup. Furthermore, our
method has been deployed to the autonomous racing vehicle of MIT Driverless,
achieving larger detection range, higher accuracy and lower latency.

该研究通过结合基于点和基于体素的模型，提出一种硬件高效的三维卷积方法，并进一步融合 稀疏卷积，以更有效地处理大场景，从硬件效率的角度系统研究三维深度学习。在此基础上，引入三维神经架构搜索来探索最佳三维网络架构，并在六个典型基准数据集上评估其性能，实现 1.8-23.7 倍的加速，已应用于 MIT Driverless 无人驾驶车辆上，实现了更大的检测范围，更高的准确性和更低的延迟。