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Novel algorithm of gait planning of hydraulic quadruped robot to avoid foot sliding and reduce impingement
Novel algorithm of gait planning of hydraulic quadruped robot to avoid foot sliding and reduce impingement
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马立玲,杨超峰,王立鹏,王军政
- , 2016, DOI: 10.15918/j.jbit1004-0579.201625.0114
Abstract: In order to solve kinematic redundancy problems of a hydraulic quadruped walking robot, which include leg dragging, sliding, impingement against the ground, an improved gait planning algorithm for this robot is proposed in this paper. First, the foot trajectory is designated as the improved composite cycloid foot trajectory. Second, the landing angle of each leg of the robot is controlled to satisfy friction cone to improve the stability performance of the robot. Then with the controllable landing angle of quadruped robot and a geometry method, the kinematic equation is derived in this paper. Finally, a gait planning method of quadruped robot is proposed, a dynamic co-simulation is done with ADAMS and MATLAB, and practical experiments are conducted. The validity of the proposed algorithm is confirmed through the co-simulation and experimentation. The results show that the robot can avoid sliding, reduce impingement, and trot stably in trot gait.
In order to solve kinematic redundancy problems of a hydraulic quadruped walking robot, which include leg dragging, sliding, impingement against the ground, an improved gait planning algorithm for this robot is proposed in this paper. First, the foot trajectory is designated as the improved composite cycloid foot trajectory. Second, the landing angle of each leg of the robot is controlled to satisfy friction cone to improve the stability performance of the robot. Then with the controllable landing angle of quadruped robot and a geometry method, the kinematic equation is derived in this paper. Finally, a gait planning method of quadruped robot is proposed, a dynamic co-simulation is done with ADAMS and MATLAB, and practical experiments are conducted. The validity of the proposed algorithm is confirmed through the co-simulation and experimentation. The results show that the robot can avoid sliding, reduce impingement, and trot stably in trot gait.
Trajectory Planning and Motion Simulation for a Hydraulic Actuated Biped Robot  [cached]
Xuewen Rong,Huixing Fan,Haiyan Wang,Xin Ma
Research Journal of Applied Sciences, Engineering and Technology , 2013,
Abstract: The purpose of this research is to generate a stable motion for a hydraulic actuated biped robot. Since the application effect of most dynamic biped robot locomotion theories is not very well and the static walk pattern is hard to realize on human-sized hydraulic actuated biped robot because of the small size of foot compared with body height. In this study, we propose a trajectory planning method based on static walking strategy. Firstly, the mechanical structure and kinematics model of the hydraulic biped robot are described. Then, we analyze why biped robot always falls backward during the walking period and propose an improved motion by adding a section of CoG movement during single support phase. The gait planning is realized with cubic spline trajectory. Finally the motion is verified with coordinated simulations based on ADAMS and MATLAB software.
Trajectory planning of jumping over obstacles for hopping robot
Xu, Zhaohong;Lü, Tiansheng;Ling, Fang;
Journal of the Brazilian Society of Mechanical Sciences and Engineering , 2008, DOI: 10.1590/S1678-58782008000400009
Abstract: trajectory planning strategy is proposed to jump over an obstacle integrated three various dynamics in one-legged multi-joint hopping robot. a concept of inertia matching ellipsoid and directional manipulability are extended to optimize take-off postures. optimized results have been used to plan hopping trajectory. aimed at the sensitivity of motion trajectory to constraint conditions, a 6th polynomial function is proposed to plan hopping motion and it has a better robustness to the parameters change of constraint conditions than traditional 5th polynomial function. during flight phase, an iterative method and angular momentum theory are used to control posture to a desired configuration. in order to lift foot over an obstacle, correction functions are constructed under unchanged boundary constraint conditions. during stance phase, robot trajectories are planned based on internal motion dynamics and steady-state consecutive hopping motion principle. a prototype model is designed, and the effectiveness of the proposed method is confirmed via simulations and experiments.
Omni-directional Walking Gait and Path Planning for Biped Humanoid Robot  [PDF]
Zai-jun Wang,Bao-fu Fang,Guo-qiang Shi
Information Technology Journal , 2013,
Abstract: Omni-directional walking is a humanoid, flexible and efficient walking way for biped humanoid robot. A method based on motion decomposition, inverse kinematics, key-frame and cubic spline interpolation is proposed to realize Omni-directional gait and walking planning. The Omni-directional gait can be seen as an integration of the three independent movements, so each movement can be planned separately. It significantly reduces the complexity of implementation, as well increases the accuracy of gait. Base on the implementation of omni-directional gait, reinforcement learning is used to optimize the walking path while tracking dynamic target in order to be more stable and efficient. Experiment shows the method is valid and efficient.
A Humanoid Robot Gait Planning and Its Stability Validation  [PDF]
Jian Zeng, Haibo Chen, Yan Yin, Yan Yin
Journal of Computer and Communications (JCC) , 2014, DOI: 10.4236/jcc.2014.211009
Abstract:

Gait planning based on linear inverted pendulum (LIPM) on structured road surface can be quickly generated because of the simple model and definite physical meaning. However, over-simplifi- cation of the model and discontents of zero velocity and acceleration boundary conditions when robot starts and stops walking lead to obvious difference between the model and the real robot. In this paper, parameterized gait is planned and trajectories’ smoothness of each joint angle and centroid are ensured using the 3-D LIPM theory. Static walking method is used to satisfy zero velocity and acceleration boundary conditions. Besides, a multi-link model is built to validate the stability. Simulation experiments show that: despite of some deviation from the theoretical solution, the actual zero-moment point (ZMP) is still within the support polygon, and the robot walks steadily. In consequence, the rationality and validity of model simplification of LIPM is demonstrated.

Trajectory Planning for Nonholonomic Mobile Robot Using Extended Kalman Filter  [PDF]
Leonimer Flavio de Melo,Jose Fernando Mangili Junior
Mathematical Problems in Engineering , 2010, DOI: 10.1155/2010/979205
Abstract: In the mobile robotic systems, a precise estimate of the robot pose with the intention of the optimization in the path planning is essential for the correct performance, on the part of the robots, for tasks that are destined to it. This paper describes the use of RF digital signal interacting with beacons for computational triangulation in the way to provide a pose estimative at bidimensional indoor environment, where GPS system is out of range. This methodology takes advantage of high-performance multicore DSP processors to calculate ToF of the order about ns. Sensors data like odometry, compass, and the result of triangulation Cartesian estimative, are fused for better position estimative. It uses a mathematical and computational tool for nonlinear systems with time-discrete sampling for pose estimative calculation of mobile robots, with the utilization of extended Kalman filter (EKF). A mobile robot platform with differential drive and nonholonomic constraints is used as a base for state space, plants and measurements models that are used in the simulations and validation of the experiments. 1. Introduction The planning of trajectory for the mobile robots, and consequently its better estimative of positioning, is the reason of intense scientific inquiry. A good path planning of trajectory is fundamental for optimization of the interrelation between the environment and the mobile robot. A great diversity of techniques based on different physical principles exists and different algorithms for the localization and the planning of the best possible trajectory. The localization in structuralized environment is helped, in general, by external elements that are called of markers. It is possible to use natural markers that already existing in the environment for the localization. Another possibility is to add intensionally to the environment artificial markers to guide the localization of the robot. This work uses an important mathematical and computational tool for the calculation of the data fusing collected by the sensors and the disturbances caused for the errors, with the purpose of estimate the mobile robot pose, that is the Extended Kalman filter (EKF). A mobile robot platform with differential traction and nonholonomics restrictions is used for experiments validation. In the direct kinematics the system of mobile robot positioning is presented. A model for state space, plants and measurements are presented, that are needed for the development of the necessary attributes to the positioning estimates made with the Extended Kalman filter. Finally, we
Gait trajectory generation for a five link bipedal robot based on a reduced dynamical model  [PDF]
Yosra Arous,Olfa Boubaker
Computer Science , 2014, DOI: 10.1109/MELCON.2012.6196594
Abstract: In this paper, a simple trajectory generation method for biped walking is proposed. The dynamic model of the five link bipedal robot is first reduced using several biologically inspired assumptions. A sinusoidal curve is then imposed to the ankle of the swing leg's trajectory. The reduced model is finally obtained and solved: it is an homogeneous second order differential equations with constant coefficients. The algebraic solution obtained ensures a stable rhythmic gait for the bipedal robot. It's continuous in the defined time interval, easy to implement when the boundary conditions are well defined.
An Efficient Strategy of Penalty Kick and Goal Keep Based on Evolutionary Walking Gait for Biped Soccer Robot  [PDF]
Yang Jingdong,Hong Bingrong,Piao Songhao,Huang Qingcheng
Information Technology Journal , 2007,
Abstract: The stabile walking gait is the basis of good performance for biped soccer robot. The ZMP trajectory is optimized to improve walking stability by the simulation in Yobotics based on evolutionary algorithms. By the rules of FIRA humanoid game, penalty kick strategy and goal keep strategy are proposed for biped soccer robot based on evolutionary gait algorithm. The penalty kick strategy includes three strategies, such as ball searching, range measurement and path planning. These strategies enable the kicker robot to finish shooting in real-time successfully. To change passive defence of goalkeeper, goal keep strategy is conducted, by which the goalkeeper is able to block the shooting of kicker effectively. Finally, through the experiment of walking gait optimization, ball color calibration and range measurement, it is validated that the evolutionary walking gait improves the walking stability and enhances the walking speed and the effectiveness of those strategies is able to adapt to the FIRA game.
Evolutionary Trajectory Planning for an Industrial Robot

R Saravanan S Ramabalan C Balamurugan A Subash,

国际自动化与计算杂志 , 2010,
Abstract: This paper presents a novel general method for computing optimal motions of an industrial robot manipulator (AdeptOne XL robot) in the presence of fixed and oscillating obstacles. The optimization model considers the nonlinear manipulator dynamics, actuator constraints, joint limits, and obstacle avoidance. The problem has 6 objective functions, 88 variables, and 21 constraints. Two evolutionary algorithms, namely, elitist non-dominated sorting genetic algorithm (NSGA-II) and multi-objective differential evolution (MODE), have been used for the optimization. Two methods (normalized weighting objective functions and average fitness factor) are used to select the best solution tradeoffs. Two multi-objective performance measures, namely solution spread measure and ratio of non-dominated individuals, are used to evaluate the Pareto optimal fronts. Two multi-objective performance measures, namely, optimizer overhead and algorithm effort, are used to find the computational effort of the optimization algorithm. The trajectories are defined by B-spline functions. The results obtained from NSGA-II and MODE are compared and analyzed.
Introduction of b-splines to trajectory planning for robot manipulators
Per E. Koch,Kesheng Wang
Modeling, Identification and Control , 1988, DOI: 10.4173/mic.1988.2.2
Abstract: This paper describes how B-splines can be used to construct joint trajectories for robot manipulators. The motion is specified by a sequence of Cartesian knots, i.e., positions and orientations of the end effector of a robot manipulator. For a six joint robot manipulator, these Cartesian knots are transformed into six sets of joint variables, with each set corresponding to a joint. Splines, represented as linear combinations of B-splines, are used to fit the sequence of joint variables for each of the six joints. A computationally very simple, recurrence formula is used to generate the 8-splines. This approach is used for the first time to establish the mathematical model of trajectory generation for robot manipulators, and offers flexibility, computational efficiency, and a compact representation.
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