Applied Mechanics and Materials Vols. 536-537

Abstract: This paper presents a theoretical analysis on a performance of an oscillating tail for water-running robots. Generally, tails are used to enhance the mobility and stability of a living creature. In this research, theoretical model is derived for an oscillating tail, and numerically solve the equations to determine the effect of the tail to the stability and lifting force. We expect the enhancement of the stability and lifting force by using the oscillating tail and results of the simulation is well-coincident with our hypothesis. The concept of oscillating tail can be extended to enhance pitching and yawing stabilities.

Abstract: To resolve the problem of obstacle avoidance and path planning of multiple robotic fishes, this paper proposes a new approach which uses collaboration mechanism based on grids method. The proposed approach splits the workspace of those robotic fishes using grids method, identifies each grid with serial number, designs the cooperative mechanism to avoid collision among these fishes, and plans the path for each fish. This method was applied in the obstacle avoidance competition of multiple robotic fishes which happening in a field with obstacle in it. The experimental results show the new method is more effective, can get more optimal path, and avoid the local minima issue which arises frequently in the A-star algorithm and genetic algorithm. It significantly improves the ability of the multiple robotic fishes system on the aspect of path planning and coordination.

Abstract: The design on distributed controller of underwater profile monitoring vehicle is investigated. We foucs on the characteristics on voltage transmission, communication and motion control precision of the vehicle, and then design a distributed controller on Underwater Profile Monitoring Vehicle. Experiment results show the effectiveness of the proposed control scheme.

Abstract: The kinematics performance comparison of a family of 3-RPS parallel mechanisms affected by limb arrangement has been studied in this paper. Firstly, arrangement parameters of single RPS limb are identified. Based on these parameters, variant configurations of 3-RPS parallel mechanisms are enumerated. Then, the inverse kinematic problems of these different mechanisms are solved, and the kinematic performance comparison of these mechanisms is carried out. Simulation results illustrate that limb arrangement has a great influence upon kinematic performance for the 3-RPS parallel mechanisms.

Abstract: Aim at special requirements and limitations of new type carrying technique for special technology well logging, one new type worming pipe robot was put forward based on combination mechanism, it can be used in the new type carrying technique. The walking principle of the robot was given and walking kinematical model and driving torque model were set up in this paper. Further more the virtual prototype was made and kinematical simulation analysis had been accomplished. The numerical results validated the design theory and analysis conclusions of the robot were correct. The robot can have bigger tensile draw.

Abstract: As the research object to IRB660 palletizing robot, its workspace is calculated. On this basis, the concept of workspace area influence coefficient and direction influence coefficient is brought forward and defined. The relationship map of coordinate plane projection area caused by robot structural parameters is drawn by MATLAB GUI programming, and the influence degree and influence direction caused by the change of unit length of the robot structural parameters is calculated precisely and quantified, which will provide a solid basis for its structural optimization and design from kinematic view.

Abstract: A robust adaptive observer was proposed for single-linked robotic arm systems, where all the parameters in the robotic arm motion equation are treated to be unknown. Under certain assumptions, the proposed observer ensures that the estimation error is uniformly bounded in the presence of unmodeled dynamics, unknown nonlinearities, bounded disturbances and unknown parameters. Furthermore, the estimation error can be made arbitrarily small by choosing appropriately design parameters. Simulation results illustrated the effectiveness of the proposed observer.

Abstract: This paper presents a real-time interpolation algorithm of the space trajectory which based on the theory of coordinate transform. The algorithm can solve the path planning problem of six-DOF robot. According to the actual movement state of robot, the algorithm can obtain some key points for the robot motion path by teaching. Then it can realize the dimensional random trajectory interpolation by coordinate transformation after building a suitable dimensional coordinate. Finally it can obtain the corresponding joint angle though the inverse kinematics solution. The experimental results show that this algorithm has a good rapidity and practicality, it suit for the six-DOF robot real-time trajectory interpolation, so it is worth promoting.

Abstract: Screw theory was introduced and inducted to the statics analysis and calculation of 6-DOF (Degree of Freedom) parallel robot. Based on the scheme, a 6-DOF parallel robot--hydraulic Stewart test platform was checked specially. The results reveal that, the platform design is appropriate, the analysis procedure is concise and the calculation operation is simple and convenient.

Abstract: A path planning method based on fruit fly optimization algorithm was proposed. An optimization algorithm by the foraging process of fruit fly was presented, and the mathematical model of fitness function was established. The algorithm steps employing the LabVIEW platform were achieved. The experiments of path planning were carried out. The experimental results show that the optimization algorithm can achieve the path planning and avoidance of mobile robot, and thus to verify the feasibility.