Spherical robot: A novel robot for exploration in harsh unknown environments

The authors propose a complete software and hardware framework for a novel spherical robot to cope with exploration in harsh and unknown environments.The proposed robot is driven by a heavy pendulum covered by a fully enclosed spherical shell,which is strongly protected,amphibious,anti-overturn and has a long-battery-life.Algorithms for location and perception,planning and motion control are comprehensively designed.On the one hand,the authors fully consider the kinematic model of a spherical robot,propose a positioning algorithm that fuses data from inertial measurement units,motor encoder and Global Navigation Satellite System,improve global path planning algorithm based on Hybrid A*and design an instruction planning controller based on model predictive control(MPC).On the other hand,the dynamic model is built,linear MPC and robust servo linear quadratic regulator algorithm is improved,and a speed controller and a direction controller are designed.In addition,based on the pose and motion charac-teristics of a spherical robot,a visual obstacle perception algorithm and an electronic image stabilisation algorithm are designed.Finally,the authors build physical systems to verify the effectiveness of the above algorithms through experiments.