A Novel Dead Reckoning System Based on Wearable Exoskeleton for Rat-Robot Localization

Rat-robots show great potential for rescue and search applications in very tight spaces because of their excellent mobility and environmental adaptability. However, owing to the complexity of the working environment, there is currently no effective localization method. In this study, we present a novel rat-robot localization system based on dead reckoning. A wearable exoskeleton was used to measure the trajectories of the rat-robot's two hindlimb ankle joints. A relational model was established to estimate the step length from the horizontal distance between the two ankle joints in the sagittal plane, and an inertial sensor obtained the heading of the rat-robot in the navigation coordinate system. The proposed system was tested by both the one-dimensional and two-dimensional locomotion experiment. The step length estimation error of our system was 0.6 +/- 3.1%, and the positioning estimation error in the two-dimensional space was 1.65 +/- 1.06%. These experimental results demonstrate the efficacy of this system in providing accurate distance and position estimation for the rat-robot.