ThermalInertial Odometry for Autonomous Flight Throughout the Night Thermal cameras can enable autonomous flight at night without GPS. However, imagebased navigation in the thermal infrared spectrum has been researched significantly less than in the visible spectrum. In this paper, we demonstrate closedloop controlled outdoor flights at night on a quadrotor. Our state estimator can tightly couple inertial data with either thermal images at nighttime, or visual images at daytime. It is integrated in an autonomy framework for motion planning and control, which runs in real time on a standard embedded computer. We analyze thermalinertial odometry performance extensively from sunset to sunrise, for various thermal nonuniformity levels, and compare it to visualinertial odometry at daytime.

A Benchmark for VisualInertial Odometry Systems Employing Onboard Illumination We present a dataset for evaluating the performance of visualinertial odometry (VIO) systems employing an onboard light source. The dataset consists of 39 sequences, recorded in mines, tunnels, and other dark environments, totaling more than 160 minutes of stereo camera video and IMU data. In each sequence, the scene is illuminated by an onboard light of approximately 1300, 4500, or 9000 lumens. We accommodate both direct and indirect visual odometry methods by providing the geometric and photometric camera calibrations (i.e. response, attenuation, and exposure times). In contrast with existing datasets, we also calibrate the light source itself and publish data for inferring more complex light models. Groundtruth position data are available for a subset of sequences, as captured by a Leica total station. All remaining sequences start and end at the same position, permitting the use of total accumulated drift as a metric for evaluation. Using our proposed benchmark, we analyze the performance of several startoftheart VO and VIO frameworks. The full dataset, including sensor data, calibration sequences, and evaluation scripts, is publicly available online at http:arpg.colorado.eduresearchoivio.