Kinematic Synthesis and Modeling of a Three Degrees-of-Freedom Hybrid Mechanism for Shoulder and Hip Modules of Humanoid Robots

This paper deals with a research work that aims to develop a new three degrees-of-freedom (DoF) hybrid mechanism for humanoid robotics application. The proposed hybrid mechanism can be used as a solution not only for several modules in humanoid robots but also for other legged robots such as quadrupeds and hexapods. Hip and shoulder mechanisms are taken as examples in this paper; torso and spine mechanisms, too, can be based on the proposed solutions. In this paper, a detailed analysis of the required performances of the hip and shoulder mechanisms is first carried out. Then, using a kinematic synthesis, a novel solution for the hip mechanism is proposed based on one rotary and two linear actuators. Improving this solution allows us to fulfill the requirements induced by the large motion ranges of the shoulder module, leading to a new management of the linear actuators contributions in the motion/force achievement process. Kinematic and geometrical models of a generic hybrid mechanism are achieved and used to get the optimized solutions of both hybrid mechanisms addressed in this paper.

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

Journal of Mechanical Design ◽

10.1115/1.4003250 ◽

2011 ◽

Vol 133 (2) ◽

Cited By ~ 12

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.

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Modelling of Continuous Contact-Based Skating Technique

Volume 5B: 42nd Mechanisms and Robotics Conference ◽

10.1115/detc2018-85598 ◽

2018 ◽

Author(s):

Varan Gupta ◽

Rohit Patel ◽

Jitendra P. Khatait ◽

I. N. Kar

Keyword(s):

Degrees Of Freedom ◽

Ground Plane ◽

Humanoid Robots ◽

Equivalent Model ◽

Continuous Contact ◽

Additional Equipment ◽

Input Signals ◽

Speed Up ◽

The Relationship ◽

Three Degrees Of Freedom

Quick locomotion has always been a challenge for humanoid robots. Most of the work has been done to improve the efficiency of the walking gaits. Recently, additional equipment like skates are increasingly being used to speed up location, but they also make the system highly unstable. This paper describes the development of a statically stable skating gait to facilitate movement across plain surfaces, such as roads and hard ice. The new gait utilises the non-holonomic nature of a wheel (or blade of an ice skate). The proposed motion of the skates on the ground plane enables it to propel the robot forward without lifting its leg. Kinematic and dynamic equations of an equivalent model are formulated. Further, the paper discusses the relationship between different input signals and their corresponding output gaits. Multibody dynamics software is then used to simulate and verify the results for various scenarios. The design of an equivalent model with three degrees of freedom is then analysed and discussed for practical testing. Finally, the algorithm was tested on a fabricated robot.

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300-N Class Convex-Based Telescopic Manipulator and Trial for 3-DOF Parallel Mechanism Robot

Journal of Robotics and Mechatronics ◽

10.20965/jrm.2021.p0141 ◽

2021 ◽

Vol 33 (1) ◽

pp. 141-150

Author(s):

Takashi Kei Saito ◽

Kento Onodera ◽

Riku Seino ◽

Takashi Okawa ◽

Yasushi Saito ◽

...

Keyword(s):

Mechanical Stress ◽

Parallel Mechanism ◽

Degrees Of Freedom ◽

Structural Problems ◽

Type K ◽

Spatial Parallel Mechanism ◽

Expansion Range ◽

Class Power ◽

Linear Actuators ◽

Three Degrees Of Freedom

We designed a new telescopic manipulator that uses a clustered elastic convex tape. The manipulator has an ultra-wide expansion range and toughness against mechanical stress. Compared to conventional linear actuators, our convex-type manipulators have high extension range and are very lightweight. Moreover, they are compact when rolled up. The telescopic manipulators designed in the previous study had insufficient output due to structural problems and were unstable. In this study, we report a Type-K telescopic manipulator mechanism (Makijaku-Ude Type-K), which is a redesigned manipulator that can be easily used with a 300-N class power, and applied the mechanism to a three degrees-of-freedom spatial parallel-mechanism robot.

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Performance Analysis of 3-URU Spherical Parallel Mechanism Designed Based on Velocity Transmission and Force Constraint Indices

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.758.71 ◽

2015 ◽

Vol 758 ◽

pp. 71-76

Author(s):

Syamsul Huda ◽

Syafri ◽

Mulyadi Bur

Keyword(s):

Parallel Mechanism ◽

Degrees Of Freedom ◽

Output Link ◽

Kinematic Synthesis ◽

Platform Motion ◽

Spherical Parallel Mechanism ◽

Velocity Transmission ◽

Maximum Inclination ◽

Three Degrees Of Freedom ◽

Spherical Motion

In this paper was observed performances of developed three degrees of freedom (dof) parallel mechanism named 3-URU spherical parallel mechanism. The mechanism is composed of three identical limbs mounted symmetrically to base (fixed link) and platform (output link). The limb is constructed by universal-revolute and universal joints. The kinematic constants of mechanism consisting of link lengths, radius of platform, radius of base, mounting angle of limb and platform to base and platform were determined with consideration of velocity transmission and force constraint indices. To evaluate performance of mechanism, it was manufactured a prototype of mechanism designed base on these two mentioned indices. There are three steps proposed to realize the mechanism, (i) kinematic synthesis to determine of kinematic constants, (ii) design of mechanical components to define shape and dimension of links and joints by considering collision in wokingspace and static analysis, (iii) evaluation of mechanism performances consisting of workingspace, controllability of platform motion and static payload. Based on obtained results, it can be clarified that, the mechanism can produce spherical motion of platform which rotates on steady point recognized as center of platform rotation. The platform can achieve maximum inclination angle, 80 degree and at this posture occurs translational error, 0.0102 mm. On the other hand, the mechanism can support payload ten times of weight of moving parts.

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A Pareto Front Mechanism Optimization for Controlling an Aircraft Using a Bio-Inspired Rotating Empennage

10.1115/detc2021-69202 ◽

2021 ◽

Author(s):

David H. Myszka ◽

James J. Joo ◽

Andrew P. Murray

Keyword(s):

Design Optimization ◽

Mechanism Design ◽

Degrees Of Freedom ◽

Pareto Front ◽

Main Axis ◽

Efficient Operation ◽

Mechanism Optimization ◽

Conflicting Objectives ◽

Linear Actuators ◽

Three Degrees Of Freedom

Abstract This paper presents a mechanism design optimization for actuating the horizontal stabilizers of an aircraft using a rotating empennage without a vertical stabilizer. Birds do not have vertical stabilizers and rotate their tail feathers to control agile maneuvers. A rotating empennage concept will mimic this motion and enable the bio-inspired flight of a fixed wing aircraft. To maintain control, the bio-inspired rotating empennage (BIRE) will incorporate three degrees of freedom: independent rotation of each horizontal stabilizer and rotation of the empennage relative to the main axis of the fuselage. The primary benefits of an aircraft without a vertical stabilizer is reduced drag and weight, which in turn results in more efficient operation. In order to reduce inertia of the rotating empennage, the linear actuators that position the horizontal stabilizers will be placed within the fuselage. Mechanisms that couple the linear translation of the actuators with the rotation of the horizontal stabilizers ideally require a low peak force and short stroke from the actuator. With two conflicting objectives, a Pareto front optimization was conducted to determine appropriate link lengths of candidate solutions and to understand the effectiveness of alternate mechanisms. The study considers a rack & pinon, scotch-yoke, slider-crank, inverted slider-crank, Watt, and Stephenson mechanisms.

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Planar In-Parallel Actuated Mechanism with Three Degrees of Freedom with Large Practically Dextrous Working Space. Kinematic Synthesis.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C ◽

10.1299/kikaic.62.2920 ◽

1996 ◽

Vol 62 (599) ◽

pp. 2920-2926 ◽

Cited By ~ 1

Author(s):

Yukio TAKEDA ◽

Hiroaki FUNABASHI ◽

Nobuyuki MURAMATSU

Keyword(s):

Degrees Of Freedom ◽

Kinematic Synthesis ◽

Working Space ◽

Three Degrees Of Freedom

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Design and Development of a Free-Standing 4-DOF Infant Surgical Table

Volume 7: 33rd Mechanisms and Robotics Conference, Parts A and B ◽

10.1115/detc2009-86790 ◽

2009 ◽

Cited By ~ 1

Author(s):

Scott R. Siebler ◽

Carl A. Nelson ◽

Thomas Hejkal

Keyword(s):

Degrees Of Freedom ◽

Vertical Movement ◽

Ball Screw ◽

Free Standing ◽

Full Size ◽

Blood Vessel Development ◽

Spherical Wrist ◽

Linear Actuators ◽

Vessel Development ◽

Three Degrees Of Freedom

Retinopathy of prematurity is caused by abnormal blood vessel development in the retina of a premature infant. Current options for surgery tables used in laser treatment of this condition are limited. Full-size operating tables or table attachments are used but provide restricted patient manipulation and cause the surgeon to assume ergonomically undesirable positions. A stand-alone four-degree-of-freedom (4-DOF) infant surgical table was designed and is presented in this paper. The new table enables the surgeon to manipulate the patient while sitting in a comfortable position. The table platform can pitch left/right and fore/aft. The table platform can rotate 360° and translate vertically. Two linear actuators and a motor with ball screw provide the three degrees of freedom for table pitch and rotation through a spherical wrist-mechanism. A ball screw and motor achieve vertical movement of the table platform. The rigors of surgery and associated space constraints were accounted for in this design. The design consists of three subassemblies which can be disassembled for transport between operating theaters. A wide base is used to prevent the table from tipping. Biocompatible materials have been selected for all parts. Lastly, foot controls are used to keep the surgeon’s hands free.

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Kinematics Modeling of a Family of Pure Translational 3-P^UR Parallel Linear Manipulators

ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, Volume 3 ◽

10.1115/esda2010-25278 ◽

2010 ◽

Author(s):

Giovanni Boschetti ◽

Roberto Caracciolo ◽

Alberto Trevisani

Keyword(s):

Analytical Solutions ◽

Degrees Of Freedom ◽

Kinematic Model ◽

Performance Indexes ◽

Kinematics Modeling ◽

Linear Actuators ◽

And Performance ◽

Three Degrees Of Freedom

This paper introduces a simplified kinematic model for a family of parallel linear manipulators with three degrees of freedom of pure translation. The P^UR topology of the limbs and the adjustable layout of the linear actuators are the main characteristics of such a family. The analytical solutions of the forward and inverse position and velocity kinematics are presented. Then the variations of the manipulator features in terms of workspace and performance indexes are investigated as functions of the actuators arrangement.

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