Latest Papers

ASME Journal of Mechanisms and Robotics

  • A Small-Scale Integrated Jumping-Crawling Robot: Design, Modeling, and Demonstration
    on June 16, 2025 at 12:00 am

    AbstractThe small jumping-crawling robot improves its obstacle-crossing ability by selecting appropriate locomotion methods. However, current research on jumping-crawling robots remains focused on enhancing specific aspects of performance, and several issues still exist, including nonadjustable gaits, poor stability, nonadjustable jumping posture, and poor motion continuity. This article presents a small jumping-crawling robot with decoupled jumping and crawling mechanisms, offline adjustable gaits, autonomous self-righting, autonomous steering, and certain slope-climbing abilities. The crawling mechanism adopts a partially adjustable Klann six-bar linkage, which can generate four stride lengths and three gaits. The jumping mechanism is designed as a six-bar linkage with passive compliance, and an active clutch allows energy storage and release in any state. The autonomous self-righting mechanism enables the robot to self-right after tipping over, meanwhile providing support, steering, and posture adjustment functions. Prototype experiments show that the designed robot demonstrates good motion stability and can climb a 45 deg slope without tipping over. The robot shows excellent steering performance, with a single action taking 5 s and achieving a steering angle of 11.5 deg. It also exhibits good motion continuity, with an average recovery time of 12 s to return to crawling mode after a jump. Crawling experiments on rough terrain demonstrate the feasibility of applying the designed robot in real-world scenarios.

Numerical and Experimental Study on Caudal Fin Oscillation Mode in Hemispherical Space

Abstract

Attaining multidimensional movements, such as cruising, diving, and turning, is a crucial challenge in the development of bionic robotic fish. When only focusing on caudal fin movements, the caudal fin of a tuna generates significant lateral and propulsive forces and weak lift, while in contrast, the caudal fin of a dolphin generates significant lift and propulsive forces and weak lateral forces. The paper introduces a novel caudal fin oscillation mode for the hemispherical space, which extends the caudal fin oscillation features observed in tuna and dolphin to a broader range of organisms. First, we presented the concept of hemispherical space caudal fin oscillation mode, and demonstrated the principle of lift distribution through theoretical calculations. Moreover, we detailed the force distribution obtained by the robotic fish under different caudal fin oscillation modes through numerical simulations. Finally, we experimentally validated the feasibility of the hemispherical space caudal fin oscillation mode. The results indicate that by modifying the oscillation mode of the caudal fin in bionic robotic fish, it is possible to distribute the lift generated by the fin movement to various forces that aid in achieving multidimensional movement, including propulsive, lateral, and lift forces.

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