Level-Headed: Evaluating Gimbal-Stabilised Visual Teach and Repeat for Improved Localisation Performance

Michael Warren, Angela P. Schoellig, Timothy D. Barfoot

Abstract: Operating in rough, unstructured terrain is an essential requirement for any truly field-deployable ground robot. Search-and-rescue, border patrol and agricultural work all require operation in environments with little established infrastructure for easy navigation. This presents challenges for sensor-based navigation such as vision, where erratic motion and feature-poor environments test feature tracking and hinder the performance of repeat matching of point features. For vision-based route-following methods such as Visual Teach and Repeat (VT&R), maintaining similar visual perspective of salient point features is critical for reliable odometry and accurate localisation over long periods. In this paper, we investigate a potential solution to these challenges by integrating a gimbaled camera with VT&R on a Grizzly Robotic Utility Vehicle (RUV) for testing at high speeds and in visually challenging environments. We examine the benefits and drawbacks of using an actively gimbaled camera to attenuate image motion and control viewpoint. We compare the use of a gimbaled camera to our traditional fixed stereo configuration and demonstrate cases of improved performance in Visual Odometry (VO), localisation and path following in several sets of outdoor experiments.