Hierarchical Sliding Mode Control for the Trajectory Tracking of a Tendon-Driven Manipulator

Abstract The tracking control of tendon-driven manipulators has recently become a hot topic. However, the flexible elastic tendon introduces greater residual vibration, making it more difficult to control the trajectory tracking of the manipulator. In this paper, a dynamics model of the elastic tendon-driven manipulator (ETDM) that considers motion coupling is established. A hierarchical sliding […]

Mobility and Kinematic Bifurcation Analysis of Origami Plate Structures

Abstract Bifurcation behavior analysis is the key part of mobility in the application of origami-inspired deployable structures because it opens up more allosteric possibilities but leads to control difficulties. A novel tracking method for bifurcation paths is proposed based on the Jacobian matrix equations of the constraint system and its Taylor expansion equations. A Jacobian […]

Kinetostatic Analysis of Pneumatic Bending Soft Actuator Coupling With Revolute Joint

Abstract This paper presents the kinetostatic analysis of pneumatic bending soft actuator coupling with revolute joint, aimed to discover the bending performance of soft actuator wearing on physical joint of human body as exoskeleton. First, a new pneumatic bidirectional bending soft actuator is designed and its mechanical characteristic is obtained by experimental tests. Then, the […]

Design of a Novel Flexible Robotic Laparoscope Using a Two Degrees-of-Freedom Cable-Driven Continuum Mechanism With Major Arc Notches

Abstract This article presents the design, development, and motion control of a novel flexible robotic laparoscope (FRL). The main structure of the FRL includes a two degrees-of-freedom (DOFs) continuum mechanism driven by two pairs of cable-pulley-driven systems, which are actuated by four miniature linear actuators. A constant-curvature model is employed on the kinematics modeling and […]

Extending Timoshenko Beam Theory for Large Deflections in Compliant Mechanisms

Abstract Compliant mechanisms (CMs) have presented its inherently advantageous properties due to the fact that CMs utilize elastic deformation of the elementary flexible members to transfer motion, force, and energy. Previously, the classic Euler–Bernoulli beam theory is the most used theory in terms of modeling large beam deflections in CMs. However, it has some assumptions […]

Shape-Adaptive Electrostatic Soft Gripper With Transform Mechanism for Multifunctional Grips

Abstract This paper proposes a shape-adaptive electroadhesion dielectric elastomer actuator (EA-DEA) pad gripper that can actively adapt to the shape of curved objects and quickly handle various objects by combining an EA pad and a multi-layered DEA driven by electrostatic force. This gripper has a rapid release function capable of detaching thin and light objects […]

A Walking Claw for Tethered Object Retrieval

Abstract Mobility and manipulation are often considered separately, with independent degrees-of-freedom (DOF) for each. However, here we show that using the legs for both walking and grasping increases the versatility of both tasks. Our robot has four DOF: drive and lift for left and right pairs of legs. The legs use a reduced actuation Klann […]

Extensible Continuum Manipulator Toward In-situ Explosive Ordnance Disposal

Abstract Homemade bombs made by terrorists threaten seriously the social public security. Now, it is still a challenge to guarantee safety without destroying bombs. Compared with the destructive explosive disposal approach employing rigid robots, we proposed an in-situ explosive disposal method, which takes advantage of an extensible continuum manipulator to pass through obstacles and cut […]

A Reconfigurable 6 R Linkage With Six Motion Modes and Three Topological Structures

Abstract In this paper, a new reconfigurable 6R linkage is obtained by combining two identical equilateral Bennett linkages arranged in a plane-symmetric manner, and a detailed kinematic analysis is conducted which shows that there are six distinct motion modes and three topological structures of the derived mechanism without changing the types of kinematic joints. Explicit […]

Thick-Panel Origami Tubes With Hexagonal Cross-Sections

Abstract Rigidly foldable origami tubes can be kinematically regarded as assemblies of spherical linkages. They have exhibited excellent properties for deployable structures. Yet, for the engineering applications, the corresponding thick-panel forms have to be designed. In this paper, the spherical 4R linkages in tubes with hexagonal cross-sections are partially replaced by spatial linkages, leading to […]