The Robot Brackets the Tunnel Exit Before It Blinds the Map

Automatic exposure can lag a rapid lighting transition, saturating frames before visual SLAM preserves enough correspondences to stay localized. B-Adapt chooses a bracket of exposures that covers scene dynamic range while retaining photometric overlap, and BVSLAM incorporates that sequence directly as factor-graph constraints instead of first merging it into HDR imagery. In a repeated tunnel-exit test at an emulated 32 meters per second, the combined method reduced state-estimation error by 78 percent against automatic-exposure images while retaining low error in nominal scenes. The comparison is specific to the tested route, speed, sensors and baselines, but it shows that exposure policy can be part of state estimation rather than a camera setting outside the robotics stack.