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.

Light-Weight Design of Five-Degree-of-Freedom Hybrid Robot for Assembling in the Cabin

Abstract

Interior assembling inside the cabin of an aircraft requires assembling robot to be light-weight and able to carry heavy payload. This paper proposed a hybrid robot and carried out its optimal design and experiments. The robot consists of a 1T2R parallel module and a 2T serial module. In the parallel module, the first limb is composed of a slider crank mechanism and a RS link. The other two limbs are PRS limbs. Herein, R, S, P are revolute, spherical, and actuated prismatic joints. Optimization of the robot concerns motion/force transmissibility, total mass, and stiffness. Hence, kinematic, stiffness, and mass modeling are implemented, and then the Pareto-based multi-objective optimization. Objective arrangements are discussed by concerning (1) the conflicting relation between mass and the minimal linear stiffness along z-axis and (2) the overall stiffness performance. After comparing six multi-objective optimizations, it is found that simultaneously regarding mass and minimal linear stiffness along z-axis as objectives is beneficial for obtaining large payload-to-mass ratio, moreover having overall stiffness as objectives would lower the values of motion/force transmissibility and payload-to-mass ratio. Finally, optimization model having motion/force transmissibility, total mass, and minimal linear stiffness along z-axis as objectives is selected. The optimal payload-to-mass ratio is up to 13.2837. The five degrees-of-freedom hybrid robot is machined and assembled. Experiments on the workspace, repeatability, and load carrying capacity confirm the performances of the designed robot.

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