In this study, we present the Differential Spiral Joint (DSJ) mechanism for variable stiffness actuation in tendon-driven robots. The DSJ mechanism semi-decouples the modulation of position and mechanical stiffness, allowing independent trajectory tracking in different parameter space. Past studies show that increasing the mechanical stiffness achieves the wider range of renderable stiffness, whereas decreasing the mechanical stiffness improves the quality of actuator decoupling and shock absorbance. Therefore, it is often useful to modulate the mechanical stiffness to balance the required level of stiffness and safety. In addition, the DSJ mechanism offers a compact form factor, which is suitable for applications where the size and weight are important. The performance of the DSJ mechanism in various areas is validated through a set of experiments.
Energy-efficient tunable-stiffness soft robots using second moment of area actuation
Southampton Marine and Maritime Institute, University of Southampton（南安普顿大学南安普顿海洋与海事研究所）；Alan Turing Institute（艾伦·图灵研究所）；Institute of Industrial Science, The University of Tokyo（东京大学生产技术研究所）
BSA -- Bi-Stiffness Actuation for optimally exploiting intrinsic compliance and inertial coupling effects in elastic joint robots
Munich Institute of Robotics and Machine Intelligence (MIRMI), Technical University of Munich（慕尼黑工业大学慕尼黑机器人与机器智能研究院（MIRMI））；Omar Al-Mukhtar University (OMU)（奥马尔·穆赫塔尔大学（OMU））
Variable Aerodynamic Damping Actuation via Co-Contraction: A Structural Analogy with Variable Stiffness Actuation
Robotics and Mechatronics, Electrical Engineering, Mathematics, and Computer Science Faculty（代尔夫特理工大学机器人与机电系，电气工程，数学和计算机科学系）；Department of Computer, Control and Management Engineering（罗马萨皮恩扎大学计算机、控制与管理工程系）
Robust Collision Detection for Robots with Variable Stiffness Actuation by Using MAD-CNN: Modularized-Attention-Dilated Convolutional Neural Network
Khalifa University Center for Autonomous and Robotic Systems, Khalifa University（哈利法大学自主与机器人系统中心，哈利法大学）；Advanced Research and Innovation Center, Khalifa University（哈利法大学高级研究与创新中心）
Muscle Coactivation in the Sky: Geometry and Pareto Optimality of Energy vs. Aerodynamic Promptness and Multirotors as Variable Stiffness Actuators
Robotics and Mechatronics Department, Electrical Engineering, Mathematics, and Computer Science (EEMCS) Faculty（代尔夫特理工大学机器人与机电系）；Department of Computer, Control and Management Engineering（罗马萨皮恩扎大学计算机、控制与管理工程系）
Shape Sensing of Variable Stiffness Soft Robots using Electrical Impedance Tomography
软机器人系统通过减少与软组织的接触创伤以及在微创手术中通过曲折路径实现入路，提供了优于传统刚性系统的益处。然而，软体机器人固有的可变形性使其形状的准确建模承担更大的责任，并且在实现术中形状感测方面面临更大的挑战。在这里，我们提出了一种本体感受（自感知）软致动器，具有导电工作流体。来自多达六个电极的电阻抗测量使得能够使用电阻抗断层扫描（EIT）进行断层扫描重建。研制了一种新的频分复用（FDM）EIT系统，能够测量66 dB SNR和20 ms的时间分辨率。两个自由度的设计：液压铰链致动器和气动手指致动器与液压梁的概念进行了研究。这两种情况都表明，阻抗测量可用于推断形状变化，并且在致动期间重建的EIT图像显示出相对于每个自由度（DOF）的不同模式。虽然观察到一些机械滞后，但测量和所得图像的可重复性很高。结果表明，作为一种低成本，低姿态的形状传感器在软体机器人的FDM-EIT的潜力。
