Abstract: A computer includes a processor and a memory, and the memory stores instructions executable by the processor to generate a set of points from a measurement scan obtained by a lidar sensor and to generate an expected termination distance of the set of points based on a neural implicit representation of the set of points. The instructions may additionally be to compute a loss function that includes a relatively low margin correlated with the variance or standard deviation of a training distribution centered at a learned point of the set of points based on the expected termination distance of the learned point, the learned point being learned by the neural implicit representation. The instructions may additionally be to generate a keyframe from the set of points and to generate a pose of the lidar sensor based on the keyframe.

Abstract: A computer that includes a processor and a memory, the memory including instructions executable by the processor to generate a current keyframe point cloud based on pairs of stereo images while a stereo camera travels through a scene determine a similar viewpoint query matrix and an opposing viewpoint query matrix based the current keyframe point cloud. A distance matrix and an opposing view distance matrix can be generated by comparing the similar viewpoint query matrix and the opposing viewpoint query matrix to reference matrices. A relative pose between a stereo camera and a reference can be determined to determine a location in the scene during travel of the stereo camera through the scene by performing sequence matching in the distance matrix and the opposing view distance matrix to determine a minimum sequence.

Abstract: A computer includes a processor and a memory, and the memory stores instructions executable by the processor to jointly train a geometric NeRF multilayer perceptron (MLP) and a color NeRF MLP to model a scene using an occupancy grid map, camera data of the scene from a camera, and lidar data of the scene from a lidar; supervise the geometric NeRF MLP with the lidar data during the joint training; and supervise the color NeRF MLP with the camera data during the joint training. The geometric NeRF MLP is a neural radiance field modeling a geometry of the scene, and the color NeRF MLP is a neural radiance field modeling colors of the scene.