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In order to establish a flexible squirm pipe robot’s mechanical model and find an appropriate method to improve its moving performance, the working qualifications and dynamic analysis of brake wheels are made. Proceed with the robot's moving mechanism, the squirm principle and mechanical qualifications of the robot’s brake wheels are analyzed, and the model of the robot’s traction is derived. Based on that, the prototype is made. Finally, the validity of the design and theories is verified by experiments.

In order to achieve the goals of small aircraft’s taking off and landing in any posture and the protection of propeller, a new single-propeller spherical aircraft structure was proposed, which had the capacity of flying in the air and walking on the ground simultaneously. An aerodynamic model of the aircraft was built. The aerodynamic characteristics of the spherical aircraft, including the lift and the anti-torque and the generated torque of the flow deflectors under the propeller’s down airflow, are studied in depth by means of CFD numerical simulation method. A reasonable design and installation program is proposed according to the research results.

A new squirming robot is designed to clean up crystal substance in chemical pipelines. The robot uses a ball screw and a motor as its driven unit, Its mechanical properties is efficiently in the pipeline. One of its advantages is its strong driven force, which is proved by theoretical analysis. The robot can clean the pipeline by some tools at the front. Through theoretical analysis, the mechanical structure can solve the pipeline environmental effects on mechanical properties

In this paper, we derive the dynamics of a spherical rolling robot, called BYQ-III, rolling without slipping on an inclined plane through the constrained Lagrange method. We present a state space realization of this constrained system, and develop a control algorithm for stabilizing the robot to track a desired trajectory on the inclined plane based on input-output feedback linearization. The validity of the proposed control scheme is then verified through simulation study.

In this paper, the dynamics and control aspects of longitudinal motion of pendulum-driven spherical robots are investigated. A simplified dynamic model is established for a spherical robot, which is an underactuated mechanical system. Based on this dynamic model, a hierarchical sliding mode controller is proposed. The stability of the whole system is verified through Lyapunov analysis, and the asymptotic stability of the sub-sliding surfaces is proved with mathematical techniques. The validity of the proposed controller is illustrated through a simulation study.

In this paper, a design of modularized flexible joint servo controller on-chip for a space manipulator system is presented. First of all, the structure and sensor system of dual-joint is introduced. The structural optimization design of the joint torque sensor is carried out with the help of the ANSYS program for weight minimization. Next, the features of the hardware system for the dual-joint controller are described. All sensor information collection within the joints are obtained with FPGA hardware logic elements using System-on-a-Programmable-Chip technology, and the joint space trajectory planning and position control are realized by Nios II soft-core processor, which is embedded in FPGA. Finally, experimental results demonstrate the effectiveness of the compact joint servo controller for the space manipulator system.

The tool falling and vibration faults often occur in the process of tool changing, In order to improve the stability of the tools on automatic tool changer, a new structure of the manipulator is presented. The new manipulator contains two-point locking instead of the original one-point locking, and the tools can be clamped more tightly. When the old manipulator is slotting the tool, the forces are analyzed, and the working load and parameters is determined by calculating and analyzing the output curve of manipulator. The three-dimensional model is built in ADMS, and the validity of the new designed manipulator is verified by the simulation in a limit state. The simulation result shows that the new manipulator can increase the ability of tool clamping effectively.

The obstacle surmounting capability of traditional spherical mobile robot is limited, especially when the spherical mobile robot comes across vertical barrier. In this paper we design a new kind of spherical mobile robot with two-mass-one-spring mechanism based on tradition spherical mobile robot. This spherical robot could not only move agility and move with the zero turning radius like traditional spherical mobile robot but also jump in three-dimensional space. In this paper we build the mathematical model of robot jumping with friction. Numeric simulations are carried out for the model using Matlab and ADAMS, we get the similar curve. These simulation results verify the validity of the mechanics model. At last we design an experimental facility, verify the model of robot jumping by experiment. Our work will be the base of model machine designing.

In order to improve the adaptability and moving stabilization of the flexible squirm robot in pipe, its key structures, including brake wheels, flexible spring axle and guide head, are optimized. For the new designed robot, its moving ability and trafficability in straight pipe and L-shape pipe are analyzed. Proceed with the robot's moving qualification, mechanical model of the robot in pipe is established and its squirming qualifications are proposed. Finally, a flexible squirm robot is developed to verify the validity of the proposed method.

FMM is an efficient algorithm in computing N-body problem. This paper firstly subdivides the FMM into 10 procedures. Based on the analysis the computing type of each procedure, we choose key procedures accelerated on FPGA and Cell BE. And then we present the speedup ratio of each accelerated procedure through experiments. Finally we analyze the computing characteristic of FMM on the computing architecture on accelerator FPGA and Cell BE.

FMM is an efficient algorithm in computing N-body problem. This paper firstly subdivides the FMM into 10 procedures. Based on the analysis the computing type of each procedure, we choose key procedures accelerated on FPGA, GPU and Cell BE. And then we present the speedup ratio of each accelerated procedure through experiments. Finally we analyze the computing characteristic of FMM on the computing architecture on accelerator FPGA and GPU on the side of P, M and C.

In order to evaluate the survivability of networked information system effectively, this paper presents a method of combining grey relation analysis and TOPSIS for quantitative assessment. Firstly, a hierarchical model of information system is constructed. Then it normalizes indicator matrix according to traditional TOPSIS method, determines the positive and negative ideal solutions, calculates the optimal dependency degree of critical services in terms of grey relation analysis, and evaluates the whole networked information system depending on the survivable function. At last this paper gives an example to show the availability and the value of the method.