scholarly journals Soft Exoskeletons: Development, Requirements, and Challenges of the Last Decade

Actuators ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 166
Author(s):  
Alan Francisco Pérez Vidal ◽  
Jesse Yoe Rumbo Morales ◽  
Gerardo Ortiz Torres ◽  
Felipe de Jesús Sorcia Vázquez ◽  
Alan Cruz Rojas ◽  
...  
Keyword(s):  
Control Systems ◽  
Degrees Of Freedom ◽  
Power Transmission ◽  
Structural Characteristics ◽  
Current Trend

In this article, various investigations on soft exoskeletons are presented and their functional and structural characteristics are analyzed. The present work is oriented to the studies of the last decade and covers the upper and lower joints, specifically the shoulder, elbow, wrist, hand, hip, knee, and ankle. Its functionality, applicability, and main characteristics are exposed, such as degrees of freedom, force, actuators, power transmission methods, control systems, and sensors. The purpose of this work is to show the current trend in the development of soft exoskeletons, in addition to specifying the essential characteristics that must be considered in its design and the challenges that its construction implies.

The Structural Synthesis of Tendon-Driven Manipulators Having a Pseudotriangular Structure Matrix

1991 ◽  
Vol 10 (3) ◽  
pp. 255-262 ◽  
Author(s):  
Jyh-Jone Lee ◽  
Lung-Wen Tsai
Keyword(s):  
Degrees Of Freedom ◽  
Power Transmission ◽  
Structural Characteristics ◽  
Mechanical Systems ◽  
Structural Synthesis ◽  
Structure Matrix ◽  
Six Degrees Of Freedom ◽  
Structural Isomorphism

Tendons have been widely used for power transmission in the field of anthropomorphic manipulating systems. This article deals with the identification and enumeration of the kine matic structure of tendon-driven robotic mechanisms. The structural isomorphism of tendon-driven manipulators is defined, and the structural characteristics of such mechanical systems are described. Applying these structural characteris tics, a methodology for the enumeration of tendon-driven robotic mechanisms is developed. Mechanism structures with up to six degrees of freedom are enumerated.

Six degrees of freedom robotic testbed for control systems laboratory

2017 ◽  
Author(s):  
Muhammad Awais Arshad ◽  
Muhammad Majid Gulzar ◽  
Jawad Khalid Qureshi ◽  
Aamir Hayat ◽  
Mohammad Shamir ◽  
...  
Keyword(s):  
Control Systems ◽  
Degrees Of Freedom ◽  
Six Degrees Of Freedom

scholarly journals Energy Consumption and Tailpipe Emission Reductions by Personalized Control of Connected Vehicles

2017 ◽  
Vol 139 (09) ◽  
pp. S5-S11
Author(s):  
Junmin Wang
Keyword(s):  
Energy Consumption ◽  
Control Systems ◽  
Degrees Of Freedom ◽  
Connected Vehicles ◽  
Emission Reductions ◽  
Physical Systems ◽  
Information Richness ◽  
Optimization And Control ◽  
Vehicle Automation ◽  
And Control

This article demonstrates several approaches to the vehicle energy consumption and tailpipe emission reduction opportunities. The article leverages the vehicle storage dynamics through smart and personalized optimization and control approaches in the context of connected vehicles. Recent advances in vehicle connectivity and automation have brought unprecedented information richness and new degrees of freedom that can be synergized with insightful understanding of vehicle powertrain and aftertreatment physical systems. Vehicle automation also provides new degrees of freedom that can be further leveraged by the vehicle control systems to improve vehicle energy efficiency and reduce tailpipe emissions. While vehicle automation levels probably will keep increasing, humans will still be involved in vehicle operations at various levels for the foreseeable future. The prediction of future vehicle’s power demand based on vehicle connectivity can significantly benefit tailpipe emission reductions and fuel economy.

Simulation Studies of the Effect of Shaft's Nonlinear Flexural Stiffness Parameters for Critical States of Rotating Power Transmission Systems

2015 ◽  
Vol 236 ◽  
pp. 62-69
Author(s):  
Tomasz Matyja ◽  
Bogusław Łazarz
Keyword(s):  
Degrees Of Freedom ◽  
Power Transmission ◽  
Flexural Stiffness ◽  
Simulation Studies ◽  
Critical States ◽  
Rotating Machine ◽  
Power Transmission Systems ◽  
Main Component ◽  
6 Degrees Of Freedom ◽  
The Impact

The paper presents simulation studies, performed using Simulink, the impact of nonlinear flexural stiffness of shafts for critical speed range and amplitude of vibration. The tests were performed on the selected model of a rotating machine, consisting of a drive, two torsional vibration dampers, shaft with mounted on it two rigid rotors (discs), supported on a three self-aligning roller bearings and mechanical power receiver (brake). The machine startup and braking with crossing the critical states was simulated using specialized Simulink library, which was developed by authors for analysis of transient states in rotating machines and flexural-torsional couplings. In accordance with the concept of modeling adopted by the authors, rotating system is divided into inertial rigid elements (rotors, bearings, clutches, etc..) and compliance elements (parts of the shaft). The main component of the currently developed library is block modeling rigid rotor with 6 degrees of freedom and with the static and dynamic unbalance. By assumption the library is a modular, expandable and allows modeling the systems of any configuration. The goal of the simulation was to verify how nonlinear flexural stiffness of shaft influences the values of critical speeds and the level of flexural and torsional vibrations.

New 3-DOFs Hybrid Mechanism for Ankle and Wrist of Humanoid Robot: Modeling, Simulation, and Experiments

2011 ◽  
Vol 133 (2) ◽  
Author(s):  
Samer Alfayad ◽  
Fethi B. Ouezdou ◽  
Faycal Namoun
Keyword(s):  
Degrees Of Freedom ◽  
Humanoid Robot ◽  
Power Transmission ◽  
Mechanical Design ◽  
Humanoid Robots ◽  
Classical Solutions ◽  
Kinematic Modeling ◽  
New Class ◽  
Hybrid Mechanism ◽  
And Control

This paper deals with the design of a new class of hybrid mechanism dedicated to humanoid robotics application. Since the designing and control of humanoid robots are still open questions, we propose the use of a new class of mechanisms in order to face several challenges that are mainly the compactness and the high power to mass ratio. Human ankle and wrist joints can be considered more compact with the highest power capacity and the lowest weight. The very important role played by these joints during locomotion or manipulation tasks makes their design and control essential to achieve a robust full size humanoid robot. The analysis of all existing humanoid robots shows that classical solutions (serial or parallel) leading to bulky and heavy structures are usually used. To face these drawbacks and get a slender humanoid robot, a novel three degrees of freedom hybrid mechanism achieved with serial and parallel substructures with a minimal number of moving parts is proposed. This hybrid mechanism that is able to achieve pitch, yaw, and roll movements can be actuated either hydraulically or electrically. For the parallel submechanism, the power transmission is achieved, thanks to cables, which allow the alignment of actuators along the shin or the forearm main axes. Hence, the proposed solution fulfills the requirements induced by both geometrical, power transmission, and biomechanics (range of motion) constraints. All stages including kinematic modeling, mechanical design, and experimentation using the HYDROïD humanoid robot’s ankle mechanism are given in order to demonstrate the novelty and the efficiency of the proposed solution.

Rotor Dynamics of Flywheel Energy Storage Systems

1991 ◽  
Vol 113 (1) ◽  
pp. 11-18 ◽  
Author(s):  
C. P. Jayaraman ◽  
J. A. Kirk ◽  
D. K. Anand ◽  
M. Anjanappa
Keyword(s):  
Control Systems ◽  
Degrees Of Freedom ◽  
Magnetic Bearing ◽  
System Stability ◽  
Dynamic Equations ◽  
Dynamic Coupling ◽  
First Order ◽  
Torque Response ◽  
Resonance Frequencies ◽  
Computer Simulation Program

This paper deals with the dynamic analysis of the magnetic bearing stack system. The stack consists of a single flywheel supported by two magnetic bearings. To model the system, the dynamic equations of a magnetically suspended flywheel are derived. Next, the four control systems controlling the four degrees-of-freedom of the stack are incorporated into the model. The resulting dynamic equations are represented as first-order differential equations in a matrix form. A computer simulation program was then used to simulate the working of the magnetic bearing stack. Real time plots from the simulation are used to show the effect of dynamic coupling on torque response. Frequency response is used to determine the resonance frequencies of the stack system. It is found that system stability depends on flywheel speed. On the basis of the above results suggestions are made to improve stability and allow the stack to be spun beyond 60,000 rpm.

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