Control of Angular Motion of the Robotic Space Module Transporting a Flexible Load

Consideration was given to designing the optimal control of a free-flying robotic space module equipped with relay actuators which carries a bulky flexible load. The procedure of designing a spatial modal-physical model of the robotic space module with a flexible load was described. For this construction, numerical analysis of the dynamic portrait which accompanies the model enables one to establish the profile of its elastic oscillations which has the form of a multiextremal function in the space of possible values of the coordinate of the point where the load is gripped by the manipulator. The global extremum (minimum) of this dependence, which was accepted as the goal function, was used as a criterion for designing the algorithm optimizing the gripper position on the load axis upon stabilizing the angular motion of the module. The calculated extremum is used in the loop of adaptive adjustment of the gripper parameter, which prevents resonance swinging of the flexible load transported to the place of installation.     

Recursive Estimation of Motion Parameters

A robust algroithm that estimates the motion parameters recursively from a sequence of noisy images is presented here. We propose the use of the least median of squares method in conjunction with a computationally efficient recursive scheme. The method works well even when nearly half of the features have been matched very poorly. A recursive constrained least squares method is developed while dealing with a range or stereo data sequence and a recursive total least squares method is proposed for the monocular data sequence.     

基于相空间重构双参数联合估计的网络流量预测

为了提高网络流量预测精度,提出一种基于相空间重构双参数联合估计的网络流量预测模型.首先采用极限学习机作为网络流量预测算法,然后预测结果优劣指选择相空间重构参数,最后建立单步、多步的网络流量预测模型,并通过仿真实验对其性能进行分析.结果表明,论文模型可以准确获得最优相空间重构参数,显著提高网络流量的预测精度,预测结果明显优于对比模型.     

基于Radon变换的运动模糊图像参数估计

运动模糊图像的参数估计直接影响图像的去模糊效果.提出了基于Radon变换的参数估计算法,结合运动模糊图像的频谱特性和Radon变换的数学含义,通过计算运动模糊图像二维频谱的Radon变换值,有效地估计出运动模糊的方向角θ和长度L两个参数.实验表明,该方法简单可行,参数估计准确,最终的图像去模糊效果良好.     

基于Radon变换的运动模糊图像参数估计

运动模糊图像的参数估计直接影响图像的去模糊效果。提出了基于Radon变换的参数估计算法,结合运动模糊图像的频谱特性和Radon变换的数学含义,通过计算运动模糊图像二维频谱的Radon变换值,有效地估计出运动模糊的方向角θ和长度L两个参数。实验表明,该方法简单可行,参数估计准确,最终的图像去模糊效果良好。     

带滑移铰空间机械臂的非完整运动规划遗传算法

本文讨论带滑移铰空间机械臂非完整运动规划的最优控制问题。利用系统的非完整特性,将带滑移铰空间机械臂运动规划转化为非线性系统最优控制问题。提出基于遗传算法的非完整运动规划最优控制方法。通过仿真计算,验证了该方法的有效性和可行性。     

Coordinated Motion and Force Control of Multi-Limbed Robotic Systems

This analytic and experimental study proposes a control algorithm for coordinated position and force control for autonomous multi-limbed mobile robotic systems. The technique is called Coordinated Jacobian Transpose Control (CJTC). Such position/force control algorithms will be required if future robotic systems are to operate effectively in unstructured environments. Generalized Control Variables (GCVs), express in a consistent and coordinated manner the desired behavior of the forces exerted by the multi-limbed robot on the environment and a system's motions. The effectiveness of this algorithm is demonstrated in simulation and laboratory experiments on a climbing system.     

Rolling Contact Motion Generation and Control of Robotic Fingers

Dexterity in human hand is connected with the fingertip rolling ability. In this work we consider rolling motion of spherical robotic fingertips as one of the control objectives together with the set point position control and force trajectory tracking. The generation of a rolling motion trajectory is proposed and a control solution is designed which achieves prescribed transient and steady state tracking behavior. The proposed control law is structurally and computationally simple and does not utilize the dynamics of the robot model or its approximation. A simulation of a five degrees of freedom robot show excellent contact rolling performance even at cases of adverse friction conditions while alternative controllers lead to contact sliding. Experiments with a KUKA LWR4 + are performed to validate the proposed method.     

Robust Estimation of Three-Dimensional Motion Parameters from a Sequence of Image Frames Using Regularization

In this paper, we look at the issue of accurate estimation of the three-dimensional motion parameters of a rigid body from a sequence of synthetic images, and relate the effect of some parameters to the shape of an error function. We first consider the case where only a small set of corresponding points is identified and suggest that a technique called regularization improves the quality and stability of a solution. We then observe that, if more pairs of corresponding points are available, the error function becomes smooth and the solution stable. Finally, we try to improve the quality of estimation by considering more than two consecutive frames for a moving camera looking at a stationary scene, and summing the error functions obtained for any two consecutive frames. Surprisingly enough, this technique does not improve stability unless we use regularization again.     

Design and Implementation of a Ubiquitous Robotic Space

This paper describes a concerted effort to design and implement a robotic service framework. The proposed framework is comprised of three conceptual spaces: physical, semantic, and virtual spaces, collectively referred to as a ubiquitous robotic space. We implemented a prototype robotic security application in an office environment, which confirmed that the proposed framework is an efficient tool for developing a robotic service employing IT infrastructure, particularly for integrating heterogeneous technologies and robotic platforms.     

Dynamics and Control of Elastic Joint Manipulators

The investigations presented in this paper are based on our previousstudies where the modeling and control problems of rigid body manipulatorswere treated through the so-called vector-parametrization of the SO(3)group. The nice property of this parametrization, which also displays a Liegroup structure, is that it drastically simplifies some considerations andreduces the computational burden in solving direct kinematic problems,inverse kinematic problems and dynamic modeling by more than 30 hitherto.This statement, which is valid for models built through vector-parameter,becomes stronger in pure vector-parameter considerations. It is provedadditionally that the computational effectiveness of the vector-parameterapproach increases with the increasing number of the revolute degrees offreedom. Here we show that this can be used successfully in the problems ofelastic joint manipulators where, besides the real n links,nfictious links are included and an additional nrevolute degrees of freedom are involved. The present paper also considersthe role of group representations of the rotation motions in the modelingand control of manipulators with elastic joints. Dynamic modelsthrough vector-parameter and in purevector-parameter form are developed and the inverse dynamic problem isdiscussed. It is shown that the nonlinear equations of motion are globallylinearizable by smooth invertible coordinate transformation and nonlinear state feedback.     

人工智能技术在机器人运动规划中的应用

机器人的运动规划问题是机器人学和人工智能中的一个重要课题。总结了国内外在机器人运动规划领域的一些典型算法,讨论了各种人工智能技术在运动规划中的应用,介绍了在空间机器人运动规划课题研究中的一些成果。     

The Onboard Algorithm for Averaging the Orbital Motion Parameters of the International Space Station in the ICARUS Experiment

This paper describes the algorithm for averaging the orbital parameters of the International Space Station (ISS), which was implemented for the International Cooperation for Animal Research Using Space (ICARUS) experiment aboard the ISS. Based on the ballistic and navigational information received from the control system, the algorithm aboard the station calculates the orbital motion parameters in the Two Line Elements format. The acquired data are averaged using the least-square method. To ensure the algorithm’s execution on the platform of the ISS onboard computer in a realtime system, the process of calculations is distributed over computational cycles. The efficiency of the proposed algorithm is demonstrated using the results of mathematical simulation.     

Variational Recursive Joint Estimation of Dense Scene Structure and Camera Motion from Monocular High Speed Traffic Sequences

We present an approach to jointly estimating camera motion and dense structure of a static scene in terms of depth maps from monocular image sequences in driver-assistance scenarios. At each instant of time, only two consecutive frames are processed as input data of a joint estimator that fully exploits second-order information of the corresponding optimization problem and effectively copes with the non-convexity due to both the imaging geometry and the manifold of motion parameters. Additionally, carefully designed Gaussian approximations enable probabilistic inference based on locally varying confidence and globally varying sensitivity due to the epipolar geometry, with respect to the high-dimensional depth map estimation. Embedding the resulting joint estimator in an online recursive framework achieves a pronounced spatio-temporal filtering effect and robustness. We evaluate hundreds of images taken from a car moving at speed up to 100 km/h and being part of a publicly available benchmark data set. The results compare favorably with two alternative settings: stereo based scene reconstruction and camera motion estimation in batch mode using multiple frames. They, however, require a calibrated camera pair or storage for more than two frames, which is less attractive from a technical viewpoint than the proposed monocular and recursive approach. In addition to real data, a synthetic sequence is considered which provides reliable ground truth.     

Technical Controllability of the Free-flying Automated Space Module

Consideration was given to the free-flying automated space module, a facility intended for servicing the orbiting space station and its accompanying objects. The notion of technical controllability of the free-flyer was introduced. A theorem about the necessary and sufficient conditions for technical controllability was proved. Methods for establishing the domains of technical controllability in the space of the generalized coordinates of object motion were proposed. By means of an illustrative example, the results of applying the notion of technical controllability were demonstrated, the domains of the given degree of technical controllability were established, and the minimal necessary vector of constraints on control of the object was determined.     

Multistructural Method of the Triangulation Estimation of the Motion Parameters of a Radiating Target under A Priori Indefiniteness Assumptions

Journal of Computer and Systems Sciences International - Based on the multistructuredness and clustering principles, as well as the filtration theory, we develop a new estimation method for the...     

An Adaptive Regulator of Robotic Manipulators in the Task Space

This note addresses the problem of position control of robotic manipulators both nonredundant and redundant in the task space. A computationally simple class of task space regulators consisting of a transpose adaptive Jacobian controller plus an adaptive term estimating generalized gravity forces is proposed. The Lyapunov stability theory is used to derive the control scheme. The conditions on controller gains ensuring asymptotic stability are obtained herein in a form of simple inequalities including some information extracted from both robot kinematic and dynamic equations. The performance of the proposed control strategy is illustrated through computer simulations for a direct-drive arm of a SCARA type redundant manipulator with the three revolute kinematic pairs operating in a two-dimensional task space.     

基于ARM和MCX314的运动控制模块的设计

本文设计了一种基于运动控制芯片MCX314的运动控制模块,并开发了一套NC代码解释程序。通过嵌入式微处理器EB44B0对运动控制芯片MCX314的寄存器和速度参数进行配置,实现对电机的精确控制。通过解释程序使得上位机能够通过标准计算机接口对模块进行NC代码编程。系统具备很高的通用性、灵活性。