Pectoral foil structure and motion discipline of cow-nosed ray as nature prototype is analyzed. A bionic pectoral fin is designed according to the analysis results. Propulsion performance of the bionic fin at sinusoidal motion law is studied experimentally on a towing platform, at the oscillating frequency from 0.2 Hz to 2 Hz and amplitude from 2.5° to 30°. Well driving ability is obtained, and maximal average thrust of 2.75N is achieved by a single bionic fin expressed at towing speed of 10 cm/s. A biomimetic fish utilizing the kind of bionic fin is developed, and swimming speed of 0.9BL (body length) in maximum can be reached.

A novel robot mechanism-tetrahedral rolling robot is introduced in the paper. The robot comprises of six extension struts and four node flats. When the COG of tetrahedron exceeds the stability region, the robot will roll. The structure of the tetrahedral rolling robot is described. Designing method of the robot is given, and it is proved correct and feasible through experiment. Kinematic model in different motion phase is analyzed in the paper, and the rolling critical condition is formulated. The effectiveness of the method is testified through simulation. The study of the paper will provide important reference for the dynamic analysis, optimization design and control of the tetrahedral rolling robot.

This paper proposed a new method of designing a flexible biomimetic fish propelled by oscillating flexible pectoral fins. The molding soft body is adopted in the robotic fish. Pneumatic artificial muscles are utilized as driving sources and two ribs with distributed flexibility as main parts of the propulsive mechanism. The leading edge locomotion profile of the flexible pectoral fin in air is studied experimentally, and the flapping locomotion in water is observed too. Finally, the effectiveness of the proposed method is illustrated by the experiment. It shows that the robotic fish can realize self-driven, and it can swim at a speed of 0.18 m/s~0.20 m/s after optimization.

This paper explores the method of designing humanoid motion considering rhythm based on human motion capture. Captured human data must be adapted for the humanoid because its kinematics and dynamics differ from those of the human actor. On the other hand, it is expected that humanoid movements are highly similar to those of the human actor. In this paper, first the motion of the human actor is segmented into primitive motions. Then, the kinematics constraints and stability adjustment method are formulated. Next, the similarity evaluation considering rhythm is discussed, and the method to derive humanoid motion with high similarity, and satisfying kinematic constraints and dynamic stability, is presented. Finally, the effectiveness of the proposed method is illustrated by the experiment of Chinese Kungfu "sword" motion using our developed humanoid robot BHR-2 with 32 DOF

The complexity of nonlinear differential equations of dynamics makes it practically impossible to obtain the walk pattern on-line through computing the whole dynamics. This paper proposed a method of online trajectory generation based on key parameters of off-line typical walk patterns for a biped humanoid. The key parameters include hip parameters, step length, walking cycle and so on. The walking pattern can be obtained according to these parameters. In order to generate walking patterns online, first the key parameters of the on-line walking pattern are computed based on the parameters of off-line typical patterns, then stability optimization has been done on-line and on-line trajectories are derived. The effectiveness of the proposed method is confirmed by simulations and experiments with our developed humanoid robot with 33 DOF.

Captured human data must be adapted for the humanoid because its kinematics and dynamics differ from those of the human actor. On the other hand, it is desirable that humanoid movements are highly similar to those of the human actor, since the human actor's motion is regarded as a teaching motion. This paper explores the design of a humanoid complicated dynamic motion based on human motion capture. First, the kinematic constraints, including ground contact conditions, are formulated. Next, the similarity evaluation and dynamic stability based on ZMP (zero moment point) of the humanoid motion are discussed, and the method to derive humanoid motion with a high similarity, and satisfying kinematic constraints and dynamic stability, is presented. Finally, the effectiveness of the proposed method is confirmed by simulations and experiments with the "sword" motion - a complicated and dynamic Chinese kungfu movement - using our developed humanoid robot with 32 degree of freedom.