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.

Locust-Inspired Jumping Mechanism Design and Improvement Based on Takeoff Stability

Abstract

Locusts keep their bodies moving in a straight line during the takeoff and maintain the body stable during the whole jumping with small pitching motions, ensuring both kinematic and dynamic stability to reach their intended destinations. Inspired by locusts’ jumping performance, the Stephenson II six-bar jumping mechanism is adopted to mimic the kinematic stability of locusts’ takeoff and a dynamic model is developed to analyze the impacts of the torsional spring location, the spring stiffness, and the location of the equivalent body bar centroid on the jumping performance. Furthermore, a revised eight-bar jumping mechanism is proposed to solve the difficulty in realizing dynamic stability using the six-bar mechanism, as the moments of momentum of each component around the overall centroid are positive and contribute together to the counterclockwise rotation of the jumping. The dynamic modeling shows that the mass of the equivalent tarsus bar plays an important role in realizing the dynamic stability for the eight-bar jumping mechanism. Finally, two kinds of jumping robots are designed, fabricated and tested with jumping performance recorded by high-speed cameras, which validates the impacts of the mass of the equivalent tarsus bar on the jumping stability in the eight-bar jumping mechanism.

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