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.

Design and Analysis of a Six-Degree-of-Freedom Microsurgical Instruments Based on Rigid-Flexible Coupling Multi-Body System

Abstract

In order to improve the operational accuracy of microsurgical instruments and increase the success rate of surgery, a six-degree-of-freedom microsurgical instrument is designed and analyzed based on a rigid-flexible coupling multi-body system. First, an improved kinematic modeling method is proposed based on the pseudo-rigid body theory. Second, a rigid-flexible coupling simulation system is built to analyze the error sources in terms of the remote center of motion, preload, and side load. Then, the function of motion scaling, the accuracy of kinematic modeling, and the validity of the workspace are demonstrated by analyzing the workspace. In addition, the maximum stress is analyzed to ensure the safety and reliability of the application. The analysis results show that the improved kinematic modeling method improves the positioning accuracy by more than two times, and the root mean square error at the tool tip of the microsurgical instrument does not exceed 1 μm under a side load of 0.1 N. Finally, the experimental results show that the improved kinematic modeling method has higher pointing accuracy, and the maximum error does not exceed 10 μm. The designed microsurgical instrument can meet the requirements of surgical operations.

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