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.