The humanoid robot BioBiped2 is powered by series elastic actuators (SEA) at the leg joints. As motivated by the human muscle architecture comprising monoarticular and biarticular muscles, the SEA at joint level are supported by elastic elements spanning two joints. In this study we demonstrate in simulation and in robot experiments, to what extend synchronous joint operation can be enhanced by...

For the present paper, we developed an output feedback chattering position regulator for n-degreesof-freedom (DOF) robot manipulators with elastic and frictional joints. A stability analysis of the closed-loop dynamic system in question was developed within the framework of Lyapunov functions. Performance issues related to the chattering regulator are illustrated in numerical simulations and ex...

Shape Memory Alloys (SMAs) are smart materials that can remember predefined shapes. A deformed SMA can transition to a trained shape by applying temperature changes to portions of the material. This reconfigurable property allows SMAs to be used in aeronautics, medicine, and other fields where dynamic re-engineering or actuation of components is required. In this work, we plan the motion of an ...

In the aim of improving safety and efficiency of robotic manipulators, links with reduced bulkiness and weight can be integrated to the robot. As a result, the manipulator becomes more flexible and might encounter vibration issues that have to be well controlled. Such flexible manipulators are said to be underactuated since they potentially have an infinite number of degrees of freedom (dof) an...

This paper describes the design concept of the performance enhanced humanoid robot LOLA. Our goal is to realize a fast, human-like walking motion. The robot has 22 degrees of freedom, including 7-DoF legs with actively driven toe joints. It is characterized by its lightweight construction, a modular, multi-sensory joint design with brushless motors and an electronics architecture using decentra...

To help people with impairment of lower extremity movement regain the ability to stand and walk, enhance limb function, this study proposes an anthropomorphic design electrically driven, lower-limb exoskeleton rehabilitation robot. The angular range robot’s motion was determined according characteristics targeted joints; robot given active–passive 12 degrees freedom. multi-degree-of-freedom hip...

This paper presents a new approach of joint velocities redistribution for kinematic fault-tolerant control of redundant robot. The suggested approach unlike the locking of failed joints can distribute special velocities to some joints of robot before or after the trouble take place, so that the robot can avoid suffering from worse joint positions and orientations, and its fault-tolerant ability...

Dynamic motion taking advantage of inertia with a flexible-joint robot is useful for energy efficiency and rapid motions. However, it is difficult to control flexible joints considering the complexity of their dynamics. To overcome the problem in past studies, oscillator [1], attractor [2], and search tree [3] methods have been explored. Attractors and oscillators force trajectories to return t...

This paper is concerned with the problem of design and implementation a robust adaptive control strategy for flexible joint electrically driven robots (FJEDR), while considering to the constraints on the actuator voltage input. The control design procedure is based on function approximation technique, to avoid saturation besides being robust against both structured and unstructured uncertaintie...

Integrated structure control design of a two-link flexible robot arm is investigated in this article. The whole arm consists of two flexible links, a fixed joint, a moving joint, and a tip load. The arm is driven by the torque motors at the two joints to reach predefined tip positions and to suppress residual flexural vibrations. The links of the arm are modeled using the finite element method ...