Latest Papers

ASME Journal of Mechanisms and Robotics

  • Mechanical Characterization of Supernumerary Robotic Tails for Human Balance Augmentation
    on August 31, 2023 at 12:00 am

    AbstractHumans are intrinsically unstable in quiet stance from a rigid body system viewpoint; however, they maintain balance, thanks to neuro-muscular sensory control properties. With increasing levels of balance related incidents in industrial and ageing populations globally each year, the development of assistive mechanisms to augment human balance is paramount. This work investigates the mechanical characteristics of kinematically dissimilar one and two degrees-of-freedom (DoF) supernumerary robotic tails for balance augmentation. Through dynamic simulations and manipulability assessments, the importance of variable coupling inertia in creating a sufficient reaction torque is highlighted. It is shown that two-DoF tails with solely revolute joints are best suited to address the balance augmentation issue. Within the two-DoF options, the characteristics of open versus closed loop tails are investigated, with the ultimate design selection requiring trade-offs between environmental workspace, biomechanical factors, and manufacturing ease to be made.

Design of a 2RRU-RRS Parallel Kinematic Mechanism for an Inner-Cavity Machining Hybrid Robot


This article presents a hybrid robot for machining the inner cavity of large-scale workpiece, and it is composed of three parts: a mobile device with 1T degree-of-freedom (DoF), a serial module with 1R1T DoFs, and a 2RRU-RRS parallel kinematic mechanism (PKM) with 2R1T DoFs. The 2RRU-RRS PKM has some advantages with a folding structure, only one S joint, two certain rotational axes, and all the fixed actuators. In this article, the conceptual design, theoretical kinematic and dynamic modeling, performance evaluation, and optimization of the parallel system are investigated. A 3D printing model is built to demonstrate the application potential. This article plays an exemplary role in the design of inner-cavity machining hybrid robots.

Read More

Journal of Mechanisms and Robotics Open Issues