Hyper-Redundant Manipulator Capable of Adjusting Its Non-Uniform Curvature with Discrete Stiffness Distribution

Abstract

Hyper-redundant manipulators are widely used in minimally invasive surgery because they can navigate through narrow passages in passive compliance with the human body. Although their stability and dexterity have been significantly improved over the years, we need manipulators that can bend with appropriate curvatures and adapt to complex environments. This paper proposes a design principle for a manipulator capable of adjusting its non-uniform curvature and predicting the bending shape. Rigid segments were serially stacked, and elastic fixtures in the form of flat springs were arranged between hinged-slide joint segments. A manipulator with a diameter of 4.5 mm and a length of 28 mm had been fabricated. A model was established to predict the bending shape through minimum potential energy theory, kinematics, and measured stiffnesses of the flat springs. A comparison of the simulation and experimental results indicated an average position error of 3.82% of the endpoints when compared to the total length. With this modification, the manipulator is expected to be widely used in various fields such as small endoscope systems and single-port robot systems.

Anti-noise kinematic controller for redundant manipulators based on model driven neural network

“…The motion control problem of the robot arm is mainly aimed at improving the motion accuracy of the robot arm. It can make the robot work under more difficult and complex tasks, such as robot surgery [4] and robot precision assembly [5] , etc., which has been a hot topic in the field of robot control. However, the precision control of redundant manipulator is a very complex problem.…”

Equilibrium Conformation of a Novel Cable-Driven Snake-Arm Robot under External Loads

“…The cable-driven snake-arm robot has been widely used in different fields, such as minimally invasive surgery [ 1 , 2 ], industrial inspection [ 3 , 4 ], and field rescue [ 5 ] in confined environments, since it has significant advantages because of its multi-DOF bending motion. Each segment of the cable-driven snake-arm robot is mainly composed of several identical 1-DOF joints or 2-DOF joints connected in series by multi-side cables.…”