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A method of constructing and maintaining a grid map using ultrasonic sensors based on Dempster-Shafer evidence theory (D-S evidence theory) is proposed with respect to the problem of unstructured unknown environment exploration and mapping. Mobile robot moving in an environment explores with ultrasonic sensors; D-S evidence theory is used to fuse information; The problem that D-S evidence theory can't be applied to information fusion under certain circumstances and the matter that D-S evidence theory have counter-intuitive behaviors in some cases are discussed; An approximate process algorithm is advanced to avoid above problems; Finally, a two-dimensional grid map is built. Application result shows that this method is appropriate for unstructured unknown environment mapping.

An omni-directional rolling spherical robot equipped with a high-rate flywheel (BYQ-V) is presented, the gyroscopic effects of high-rate flywheel can further enhance the dynamic stability of the spherical robot. This robot is designed for territory or lunar exploration in the future. The mechanical structure and control system of the robot are given particularly. Using the constrained Lagrangian method, the simplified dynamic model of the robot is derived under some assumptions, Moreover, a Linear Quadratic Regulator (LQR) controller and Percentage Derivative (PD) controller are designed to implement the pose and velocity control of the robot respectively, Finally, the dynamic model and the controllers are validated through simulation study and prototype experiment.

In this paper, an omni-directional rolling spherical robot with telescopic manipulator (BYQ-IV) is presented. This robot is designed for territory or lunar exploration. It not only has features like straight line motion, circular motion, zero turning radius and obstacle avoidance, but also is able to accomplish tasks such as stably grabbing and delivering assemblies. The structure of the whole robot is divided into three sub-systems, including the motion driving system; the manipulator system and the stability maintain system. Moreover, the distribute control system of the robot based on ARM processor and wireless communication system are introduced and the software architecture of control system is analyzed. The experiment shows that the prototype of the spherical robot with telescopic manipulator (BYQ-IV) can stably grasp a static target and carry it to a new location.

Based on ARM processor and FPGA co-processor, kinematics control for a 6-DOF (degree of freedom) space manipulator is realized in this paper. The ARM processor uses AT91FR40162, which mainly takes charge of the tractory planning for the space manipulator. Meanwhile, using the CORDIC (Coordinate Rotation Digital Computer) algorithm, the forward and inverse kinematics computation of the space manipulator are implemented in FPGA. This approach can effectively reduce the calculation time of kinematics control and optimize real-time performance of the space manipulator. The principle and architecture of CORDIC IP core are presented, and CORDIC-based pipelines for the kinematics computation are depicted. Furthermore, a novel fault-tolerance central controller for the space manipulator using ARM processor and FPGA co-processor is developed and the control flow is presented particularly. The ground simulative zero-gravity experiment shows that the performance of the central controller meets the real-time and accuracy requirement of the space manipulator.