Explosive Electric Actuator and Control for Legged Robots

Design and control of micro robots have been one of the interesting fields in robotics in recent years. One class of these micro robots is the legged robots. Various designs of legged robots have been proposed in the literature. All designs rely on friction for locomotion. In this paper dynamic model of a planar two-legged micro robot is presented using Luger friction model, and an adaptive neural controller used to control the robot to improve robustness and velocity of the robot. As mentioned earlier, friction plays an important role in locomotion of the legged robots. However, especially in legged micro robots, it is difficult to model the frictional force correctly since environmental disturbances like dust and changes in shape of the test bed can significantly alter its value. Therefore, one needs to design a controller that adapt to new condition and had enough robustness so one chooses neural network controller. Result show that with updating weight of neural network robot could follow desired trajectory, and with change in friction coefficient training time was low enough to update weight at each step.

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2A2-J15 Development of Super-Robust HFD Electric Actuator : Fundamentals and Mechanism of Prototype Actuator installed in UMRS2009(Mechanism and Control for Actuator)

The Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec) ◽

10.1299/jsmermd.2011._2a2-j15_1 ◽

2011 ◽

Vol 2011 (0) ◽

pp. _2A2-J15_1-_2A2-J15_2

Author(s):

Hidetake IWASAKI ◽

Sakae UMEDA ◽

Yuuta HAMASAKI ◽

Sigeru KOBAYASHI ◽

Yoshikazu OHTSUBO ◽

...

Keyword(s):

Electric Actuator ◽

And Control

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Towards Online Impact Force Dynamic Parameters Identification for Hydraulic Legged Robots

Volume 6: 12th International Conference on Multibody Systems, Nonlinear Dynamics, and Control ◽

10.1115/detc2016-60592 ◽

2016 ◽

Author(s):

Mariapaola D’Imperio ◽

Ferdinando Cannella

Keyword(s):

Rate Increase ◽

Impact Force ◽

Reaction Force ◽

Experimental Tests ◽

Parameters Identification ◽

Legged Robots ◽

Stable Manner ◽

Impact Phenomena ◽

Design Integration ◽

And Control

The design and control of legged robots capable of performing dynamic tasks, such as those involving impact in a stable manner, is of growing concern within the robotics community. Under these conditions, ground reaction force rate increase dramatically and, if the control system fails to response appropriately, the internal vibrations will damage the robotic structure. To deal with these problems, design integration between control, mechanics and electronics is required. As a means to co-develop these tasks, we present an alternative method, based on the Virtual Prototyping (VP) and cosimulation concept, to model impact phenomena for design purposes. This model has been built starting from the identification of all the parameters that affect object dynamics within the mechanical structure. Two campaigns of experimental tests have been carried out: the first one for the parameters identification, while the second one for the model validation process. The agreement between numerical results and experiments is very satisfactory, demonstrating the possibility of using the model for future mechanical and control co-development.

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All common bipedal gaits emerge from a single passive model

Journal of The Royal Society Interface ◽

10.1098/rsif.2018.0455 ◽

2018 ◽

Vol 15 (146) ◽

pp. 20180455 ◽

Cited By ~ 6

Author(s):

Zhenyu Gan ◽

Yevgeniy Yesilevskiy ◽

Petr Zaytsev ◽

C. David Remy

Keyword(s):

Vertical Motion ◽

Legged Robots ◽

Nonlinear Modes ◽

One Dimensional ◽

Leg Motion ◽

Mechanical Dynamics ◽

And Control ◽

Parameter Values ◽

Single Set ◽

Passive Model

In this paper, we systematically investigate passive gaits that emerge from the natural mechanical dynamics of a bipedal system. We use an energetically conservative model of a simple spring-leg biped that exhibits well-defined swing leg dynamics. Through a targeted continuation of periodic motions of this model, we systematically identify different gaits that emerge from simple bouncing in place. We show that these gaits arise along one-dimensional manifolds that bifurcate into different branches with distinctly different motions. The branching is associated with repeated breaks in symmetry of the motion. Among others, the resulting passive dynamic gaits include walking, running, hopping, skipping and galloping. Our work establishes that the most common bipedal gaits can be obtained as different oscillatory motions (or nonlinear modes) of a single mechanical system with a single set of parameter values. For each of these gaits, the timing of swing leg motion and vertical motion is matched. This work thus supports the notion that different gaits are primarily a manifestation of the underlying natural mechanical dynamics of a legged system. Our results might explain the prevalence of certain gaits in nature, and may provide a blueprint for the design and control of energetically economical legged robots.

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An Interactive Software Environment for Gait Generation and Control Design of Sony Legged Robots

RoboCup 2002: Robot Soccer World Cup VI - Lecture Notes in Computer Science ◽

10.1007/978-3-540-45135-8_22 ◽

2003 ◽

pp. 279-287 ◽

Cited By ~ 4

Author(s):

Dragos Golubovic ◽

Huosheng Hu

Keyword(s):

Control Design ◽

Legged Robots ◽

Interactive Software ◽

Software Environment ◽

Gait Generation ◽

And Control

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Single-legged hopping robotics research—A review

Robotica ◽

10.1017/s0263574707003487 ◽

2007 ◽

Vol 25 (5) ◽

pp. 587-613 ◽

Cited By ~ 53

Author(s):

Ajij Sayyad ◽

B. Seth ◽

P. Seshu

Keyword(s):

Large Fraction ◽

Dynamical Behavior ◽

Theoretical Models ◽

Human Locomotion ◽

Legged Robots ◽

Nonlinear Dynamical ◽

Modeling And Control ◽

Highly Nonlinear ◽

Hopping Robots ◽

And Control

SUMMARYInspired by the agility of animal and human locomotion, the number of researchers studying and developing legged robots has been increasing at a rapid rate over the last few decades. In comparison to multilegged robots, single-legged robots have only one type of locomotion gait, i.e., hopping, which represents a highly nonlinear dynamical behavior consisting of alternating flight and stance phases. Hopping motion has to be dynamically stabilized and presents challenging control problems. A large fraction of studies on legged robots has focused on modeling and control of single-legged hopping machines. In this paper, we present a comprehensive review of developments in the field of single-legged hopping robots. We have attempted to cover development of prototype models as well as theoretical models of such hopping systems.

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Motion planning and implementation for the self-recovery of an overturned multi-legged robot

Robotica ◽

10.1017/s0263574715001009 ◽

2015 ◽

Vol 35 (5) ◽

pp. 1107-1120 ◽

Cited By ~ 7

Author(s):

Saijin Peng ◽

Xilun Ding ◽

Fan Yang ◽

Kun Xu

Keyword(s):

Motion Planning ◽

The Body ◽

The Self ◽

Legged Robots ◽

Ground Reaction Forces ◽

Robot Design ◽

Legged Robot ◽

Reaction Forces ◽

Recovery Approach ◽

And Control

SUMMARYThis paper first presents a method of motion planning and implementation for the self-recovery of an overturned six-legged robot. Previous studies aimed at the static and dynamic stabilization of robots for preventing them from overturning. However, no one can guarantee that an overturn accident will not occur during various applications of robots. Therefore, the problems involving overturning should be considered and solved during robot design and control. The design inspirations of multi-legged robots come from nature, especially insects and mammals. In addition, the self-recovery approach of an insect could also be imitated by robots. In this paper, such a self-recovery mechanism is reported. The inertial forces of the dangling legs are used to bias some legs to touch the ground, and the ground reaction forces exerted on the feet of landing legs are achieved to support and push the body to enable recovery without additional help. By employing the mechanism, a self-recovery approach named SSR (Sidewise-Self-Recovery) is presented and applied to multi-legged robots. Experiments of NOROS are performed to validate the effectiveness of the self-recovery motions. The results show that the SSR is a suitable method for multi-legged robots and that the hemisphere shell of robots can help them to perform self-recovery.

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Java Simulator for Quadruped Walking Robot

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.166-167.445 ◽

2010 ◽

Vol 166-167 ◽

pp. 445-450

Author(s):

Steliana Vatau ◽

Valentin Ciupe ◽

Inocentiu Maniu

Keyword(s):

Legged Robots ◽

High Dimensional ◽

Legged Robot ◽

Walking Robot ◽

Quadruped Locomotion ◽

Java Language ◽

Cross Platform ◽

Simulation And Control ◽

Physics Based Simulation ◽

And Control

With advances in science and technology, the interest to study the animals walking has developed the demand for building the legged robots. Physics-based simulation and control of quadruped locomotion is difficult because quadrupeds are unstable, under actuated, high-dimensional dynamical systems. We develop a simple control strategy that can be used to generate a large variety of gaits and styles in real-time, including walking in all directions (forwards, backwards, sideways, turning). The application named JQuadRobot is developed in Java and Java3D API. A Graphical User Interface and a simulator for a custom quadruped leg's robot and the main features of the interface are presented in this paper. This application is developed in Java and is essential in a development motion for legged robot. The friendly interface, allows any user to define and test movements for this robot. The cross-platform capability was the first reason to choose Java language for developing this application.

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Design and Control of 7-DOF Omni-directional Hexapod Robot

Open Computer Science ◽

10.1515/comp-2020-0189 ◽

2020 ◽

Vol 11 (1) ◽

pp. 80-89

Author(s):

Marek Žák ◽

Jaroslav Rozman ◽

František V. Zbořil

Keyword(s):

Degrees Of Freedom ◽

Travel Speed ◽

Legged Robots ◽

Movement Speed ◽

Legged Robot ◽

Hexapod Robot ◽

Unique Combination ◽

Two Degrees Of Freedom ◽

And Control ◽

Omnidirectional Wheels

AbstractLegged robots have great potential to travel across various types of terrain. Their many degrees of freedom enable them to navigate through difficult terrains, narrow spaces or various obstacles and they can move even after losing a leg. However, legged robots mostly move quite slowly. This paper deals with the design and construction of an omni-directional seven degrees of freedom hexapod (i.e., six-legged) robot, which is equipped with omnidirectional wheels (two degrees of freedom are used, one for turning the wheel and one for the wheel itself) usable on flat terrain to increase travel speed and an additional coxa joint that makes the robot more robust when climbing inclined terrains. This unique combination of omnidirectional wheels and additional coxa joint makes the robot not only much faster but also more robust in rough terrains and allows the robot to ride inclined terrains up to 40 degrees and remain statically stable in slopes up to 50 degrees. The robot is controlled by a terrain adaptive movement controller which adjusts the movement speed and the gait of the robot according to terrain conditions.

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