The Workspace Analysis of Quadruped Robot Regarded As a Parallel Manipulator Under Different Configurations

Volume 5A: 42nd Mechanisms and Robotics Conference ◽

10.1115/detc2018-86353 ◽

2018 ◽

Author(s):

Nan Ma ◽

Jingjun Yu

Keyword(s):

Parallel Manipulator ◽

First Generation ◽

Inverse Kinematic ◽

Quadruped Robot ◽

Structure Characteristic ◽

Quadruped Robots ◽

Workspace Analysis ◽

Capability Analysis ◽

Static Performance ◽

The Given

The quadruped mammal is one kind of animal that has the excellent motion performances (i.e. walking stability, running speed and body flexibility). Lots of attentions have focused on imitating structure/characteristic of these quadruped animals to promote the development in quadruped robot in recent years. Most of the researches are concentrated on the motion capability analysis of the quadruped robots, However, the workspace variation, which is an important characteristic to scale the static manipulation ability when the quadruped is standing with the four feet fixed on the ground, is ignored by the most of researchers. In this paper, the workspace variation of quadruped robot, when regarded as a parallel manipulator with for foot fixed on ground as a case, is studied using the first generation of MANA robot to explore feet configuration on the influence of workspace variation. This quadruped robot is designed based on the mammal skeleton, which can realize the motion of robot body by alternating the motions in four legs. Firstly, the performance indicators of the MANA are given. Then, the MANA robot is regarded as a parallel platform with four feet fixed on the ground, thus, the corresponding inverse kinematic equations are used to calculate the workspace under the given configuration. After that, variables (i.e. positions of the feet and body posture) are defined to analyze the influence on the workspace variation. At last, four cases are studied to research the overall influence of foot configurations on the workspace variation. The workspace variation analysis of the quadruped can help to optimize the feet configuration for the getting the better manipulator ability, which expands the static performance for quadruped robot.

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Motion capability analysis of a quadruped robot as a parallel manipulator

Frontiers of Mechanical Engineering ◽

10.1007/s11465-014-0317-7 ◽

2014 ◽

Vol 9 (4) ◽

pp. 295-307 ◽

Cited By ~ 1

Author(s):

Jingjun Yu ◽

Dengfeng Lu ◽

Zhongxiang Zhang ◽

Xu Pei

Keyword(s):

Parallel Manipulator ◽

Quadruped Robot ◽

Capability Analysis

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Creeping Gait Analysis and Simulation of a Quadruped Robot

Al-Khwarizmi Engineering Journal ◽

10.22153/kej.2018.12.004 ◽

2019 ◽

Vol 14 (2) ◽

pp. 93-106

Author(s):

Firas A. Raheem ◽

Murtadha Khudhair Flayyih

Keyword(s):

Sequence Analysis ◽

Gait Analysis ◽

Inverse Kinematic ◽

Quadruped Robot ◽

Legged Robot ◽

Stability Margins ◽

Robot Locomotion ◽

Quadruped Robots ◽

Kinematic Models ◽

The Stability

A quadruped (four-legged) robot locomotion has the potential ability for using in different applications such as walking over soft and rough terrains and to grantee the mobility and flexibility. In general, quadruped robots have three main periodic gaits: creeping gait, running gait and galloping gait. The main problem of the quadruped robot during walking is the needing to be statically stable for slow gaits such as creeping gait. The statically stable walking as a condition depends on the stability margins that calculated particularly for this gait. In this paper, the creeping gait sequence analysis of each leg step during the swing and fixed phases has been carried out. The calculation of the minimum stability margins depends upon the forward and inverse kinematic models for each 3-DOF leg and depends on vertical geometrical projection during walking. Simulation and results verify the stability insurance after calculation the minimum margins which indicate clearly the robot COG (Center of Gravity) inside the supporting polygon resulted from the leg-tips.

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Structural Design, Simulation and Experiment of Quadruped Robot

Applied Sciences ◽

10.3390/app112210705 ◽

2021 ◽

Vol 11 (22) ◽

pp. 10705

Author(s):

Yunde Shi ◽

Shilin Li ◽

Mingqiu Guo ◽

Yuan Yang ◽

Dan Xia ◽

...

Keyword(s):

Attitude Control ◽

Inverse Kinematic ◽

Quadruped Robot ◽

Contact Modeling ◽

Gait Planning ◽

Quadruped Robots ◽

Pendulum Equation ◽

Physical Prototype ◽

Simulation And Experiment ◽

Bionic Structure

This paper carried out a series of designs, simulations and implementations by using the physical-like mechanism of a bionic quadruped robot dog as a vehicle. Through an investigation of the walking mechanisms of quadrupeds, a bionic structure is proposed that is capable of omnidirectional movements and smooth motions. Furthermore, the kinematic and inverse kinematic solutions based on the DH method are explored to lay the foundation for the gait algorithm. Afterward, a classical compound pendulum equation is applied as the foot-end trajectory and inverse kinematic solutions are combined to complete the gait planning. With appropriate foot–ground contact modeling, MATLAB and ADAMS are used to simulate the dynamic behavior and the diagonal trot gait of the quadruped robot. Finally, the physical prototype is constructed, designed and debugged, and its performance is measured through real-world experiments. Results show that the quadruped robot is able to balance itself during trot motion, for both its pitch and roll attitude. The goal of this work is to provide an affordable yet comprehensive platform for novice researchers in the field to study the dynamics, contact modeling, gait planning and attitude control of quadruped robots.

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Determination of the Workspace of a Three-Degrees-of-Freedom Parallel Manipulator Using a Three-Dimensional Computer-Aided-Design Software Package and the Concept of Virtual Chains1

Journal of Mechanisms and Robotics ◽

10.1115/1.4031656 ◽

2015 ◽

Vol 8 (2) ◽

Cited By ~ 7

Author(s):

Andrew Johnson ◽

Xianwen Kong ◽

James Ritchie

Keyword(s):

Computer Aided Design ◽

Parallel Manipulator ◽

Degrees Of Freedom ◽

Graphical Representation ◽

Three Dimensional ◽

Parallel Manipulators ◽

Workspace Analysis ◽

Computer Aided ◽

Aided Design

The determination of workspace is an essential step in the development of parallel manipulators. By extending the virtual-chain (VC) approach to the type synthesis of parallel manipulators, this technical brief proposes a VC approach to the workspace analysis of parallel manipulators. This method is first outlined before being illustrated by the production of a three-dimensional (3D) computer-aided-design (CAD) model of a 3-RPS parallel manipulator and evaluating it for the workspace of the manipulator. Here, R, P and S denote revolute, prismatic and spherical joints respectively. The VC represents the motion capability of moving platform of a manipulator and is shown to be very useful in the production of a graphical representation of the workspace. Using this approach, the link interferences and certain transmission indices can be easily taken into consideration in determining the workspace of a parallel manipulator.

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Regions of Feasible Point-to-Point Trajectories in the Cartesian Workspace of Fully-Parallel Manipulators

Volume 1: 25th Design Automation Conference ◽

10.1115/detc99/dac-8645 ◽

1999 ◽

Author(s):

Damien Chablat ◽

Philippe Wenger

Keyword(s):

Parallel Manipulator ◽

Cartesian Product ◽

Parallel Manipulators ◽

Joint Space ◽

Inverse Kinematic ◽

Connected Components ◽

Feasible Point ◽

Cartesian Space ◽

Point Trajectories ◽

Point To Point

Abstract The goal of this paper is to define the n-connected regions in the Cartesian workspace of fully-parallel manipulators, i.e. the maximal regions where it is possible to execute point-to-point motions. The manipulators considered in this study may have multiple direct and inverse kinematic solutions. The N-connected regions are characterized by projection, onto the Cartesian workspace, of the connected components of the reachable configuration space defined in the Cartesian product of the Cartesian space by the joint space. Generalized octree models are used for the construction of all spaces. This study is illustrated with a simple planar fully-parallel manipulator.

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The Complex Dynamic Locomotive Control and Experimental Research of a Quadruped-Robot Based on the Robot Trunk

Applied Sciences ◽

10.3390/app9183911 ◽

2019 ◽

Vol 9 (18) ◽

pp. 3911 ◽

Cited By ~ 4

Author(s):

Dongyi Ren ◽

Junpeng Shao ◽

Guitao Sun ◽

Xuan Shao

Keyword(s):

Control Strategy ◽

Kinematic Model ◽

Quadruped Robot ◽

Contact Forces ◽

Small Magnitude ◽

Feedback Information ◽

Joint Torques ◽

Trunk Motion ◽

Quadruped Robots ◽

Leg Motion

The research of quadruped robots is fundamentally motivated by their excellent performance in complex terrain. Maintaining the trunk moving smoothly is the basis of assuring the stable locomotion of the robot. In this paper we propose a planning and control strategy for the pacing gait of hydraulic quadruped robots based on the centroid. Initially, the kinematic model between the single leg and the robot trunk was established. The coupling of trunk motion and leg motion was elaborated on in detail. Then, the real-time attitude feedback information of the trunk was considered, the motion trajectory of the trunk centroid was planned, and the foot trajectory of the robot was carried out. Further, the joint torques were calculated that fulfillment minimization of the contact forces. The position and attitude of the robot trunk were adjusted by the presented controller. Finally, the performance of the proposed control framework was tested in simulations and on a robot platform. By comparing the attitude of the robot trunk, the experimental results show that the trunk moved smoothly with small-magnitude by the proposed controller. The stable dynamic motion of the hydraulic quadruped robot was accomplished, which verified the effectiveness and feasibility of the proposed control strategy.

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Gait Tracking Control of Quadruped Robot Using Differential Evolution Based Structure Specified Mixed SensitivityH∞Robust Control

Journal of Control Science and Engineering ◽

10.1155/2016/8760215 ◽

2016 ◽

Vol 2016 ◽

pp. 1-18 ◽

Cited By ~ 3

Author(s):

Petrus Sutyasadi ◽

Manukid Parnichkun

Keyword(s):

Tracking Control ◽

Control Algorithm ◽

Joint Angle ◽

Gait Pattern ◽

Quadruped Robot ◽

Robust Controller ◽

Quadruped Robots ◽

Parameter Variations ◽

Real Hardware ◽

Dynamic Gait

This paper proposed a control algorithm that guarantees gait tracking performance for quadruped robots. During dynamic gait motion, such as trotting, the quadruped robot is unstable. In addition to uncertainties of parameters and unmodeled dynamics, the quadruped robot always faces some disturbances. The uncertainties and disturbances contribute significant perturbation to the dynamic gait motion control of the quadruped robot. Failing to track the gait pattern properly propagates instability to the whole system and can cause the robot to fall. To overcome the uncertainties and disturbances, structured specified mixed sensitivityH∞robust controller was proposed to control the quadruped robot legs’ joint angle positions. Before application to the real hardware, the proposed controller was tested on the quadruped robot’s leg planar dynamic model using MATLAB. The proposed controller can control the robot’s legs efficiently even under uncertainties from a set of model parameter variations. The robot was also able to maintain its stability even when it was tested under several terrain disturbances.

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Stability Margin of a Metamorphic Quadruped Robot With a Twisting Trunk

Journal of Mechanisms and Robotics ◽

10.1115/1.4044600 ◽

2019 ◽

Vol 11 (6) ◽

Cited By ~ 1

Author(s):

Chunsong Zhang ◽

Chi Zhang ◽

Jian S. Dai ◽

Peng Qi

Keyword(s):

Closed Loop ◽

Stability Margin ◽

Rigid Bodies ◽

Quadruped Robot ◽

Quadruped Robots ◽

Kinematic Performance ◽

The Stability ◽

Twisting Angle

Abstract To date, most quadruped robots are either equipped with trunks that are rigid bodies or consist of blocks connected by passive joints. The kinematic performance of these quadruped robots is only determined by their legs. To release the mobility of trunks and enhance the performance of quadruped robots, this paper proposes a metamorphic quadruped robot with a moveable trunk (a planar six-bar closed-loop linkage), called MetaRobot I, which can implement active trunk motions. The robot can twist its trunk like natural quadrupeds. Through trunk twisting, the stability margin of the quadruped robot can be increased compared with that of a quadruped robot with a rigid trunk. The inner relationship between the stability margin and the twisting angle is analyzed in this paper. Finally, simulations are carried out to show the benefits facilitated by the twisting trunk to the quadruped robot.

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