Real-time 3D mapping is a critical component in many important applications today including robotics, AR/VR, and 3D visualization. 3D mapping involves continuously fusing depth maps obtained from depth sensors in phones, robots, and autonomous vehicles into a single 3D representative model of the scene. Many important applications, e.g., global path planning and trajectory generation in micro aerial vehicles, require the construction of large maps at high resolutions. In this work, we identify mapping, i.e., construction and updates of 3D maps to be a critical bottleneck in these applications. The memory required and access times of these maps limit the size of the environment and the resolution with which the environment can be feasibly mapped, especially in resource constrained environments such as autonomous robot platforms and portable devices. To address this challenge, we propose VoxelCache: a hardware-software technique to accelerate map data access times in 3D mapping applications. We observe that mapping applications typically access voxels in the map that are spatially co-located to each other. We leverage this temporal locality in voxel accesses to cache indices to blocks of voxels to enable quick lookup and avoid expensive access times. We evaluate VoxelCache on popularly used mapping and reconstruction applications on both GPUs and CPUs. We demonstrate an average speedup of 1.47X (up to 1.66X) and 1.79X (up to 1.91X) on CPUs and GPUs respectively.
翻译:实时 3D 映射是当今许多重要应用中的关键组成部分,包括机器人、AR/VR 和 3D 可视化。 3D 映射涉及不断将从电话、机器人和自主车辆的深度传感器中获得的深度地图转化为单一的3D代表模型。许多重要应用,例如全球路径规划和微型飞行器的轨迹生成,需要建造高分辨率的大地图。在这项工作中,我们确定映射,即3D地图的构造和更新将成为这些应用中的关键瓶颈。这些地图的记忆和存取时间限制了环境的大小和环境可进行可操作制图的分辨率,特别是在自主机器人平台和便携式装置等资源受限的环境中。为了应对这一挑战,我们建议VoxelCache:一种硬件软件技术,以加快3D 映射应用程序中的地图访问时间。我们观察到,绘图应用程序通常访问地图中的毒物,而这些毒物彼此在空间上合用。 我们利用这个时间点评估了Voxel访问缓存指标的大小,分别用于 voxel-C 和 Vxxex 的快速地图应用。