气动人工肌肉驱动球面并联机器人关节的力控制研究

分析了具有柔索冗余驱动特点的静力关系，研究了力控制的智能控制算法及策略，在建立的实验样机上达到了良好的力伺服性能．将气动人工肌肉的被动柔顺性与位置控制到力控制过渡的主动柔顺控制策略结合，有效避免了机器人在与环境接触时的碰撞与冲击．     

气动人工肌肉关节的迭代反馈整定控制及优化

气动人工肌肉关节（PMA）具有低成本、柔顺性和与生物肌肉类似的力学特性等优点，在医疗设备、仿生机器人等领域得到广泛应用.本文针对气动人工肌肉充气变形过程中存在的强非线性、时变性和控制参数难以确定的问题，提出了一种基于迭代反馈整定（IFT）算法的数据驱动优化控制策略，直接基于系统的输入输出数据，定义跟踪性能准则函数并采用Gauss-Newton估计算法实现对PID控制器参数的迭代整定，并通过引入辅助因子获取性能准则函数加权因子的最优值进一步加快了IFT算法的收敛速度.仿真结果表明，该方法相对于Ziegler-Nichols等传统PID参数整定方法可以有效提高控制系统的跟踪性能和鲁棒性.     

一种气动肌肉拮抗驱动机器人关节的类人运动控制方法

为了实现气动人工肌肉拮抗驱动机器人关节系统的类人运动控制,针对该系统严重非线性的特点,本文将其控制问题视为一个非线性最优控制问题,根据人体手臂关节运动的最小加加速度模型设定系统的最优控制性能指标,首先采用扩张状态观测器将机器人关节模型线性化得到积分器串联标准型,然后在线性化模型基础上设计最优控制律,使机器人关节具有与人手臂关节相似的无约束运动轨迹.仿真结果表明,采用本文算法,机器人关节能实现大运动范围(0～120°)的类人运动,关节运动轨迹对负载的改变(1 kg～5 kg)不敏感,并且关节运动具有较好的抗扰动能力.在机器人关节实验平台上通过实物实验验证了算法的有效性,并进一步讨论了控制器参数的设计规则.本文算法需要整定的参数只有2个,适用于气动肌肉拮抗驱动关节的类人运动控制,能够满足协作机器人在本质安全性、运动柔顺性以及类人运动模式等方面的要求.     

基于细径McKibben型气动人工肌肉的仿生手研发

以细径McKibben型气动人工肌肉作为执行器,研发了一种质量轻且具有良好柔顺性、灵巧性的仿生机械手.分别以直径为1.3mm和2mm的细径McKibben型人工肌肉模拟人手的内在肌和外在肌,以人手骨骼、关节、肌肉的生理构造为设计准则,设计并制作仿生手样机.该样机由35根人工肌肉驱动,与人手大小相仿,质量小于0.5 kg.通过实验,对该仿生手的运动性能、目标抓握能力和鲁棒性进行验证,该仿生手可以完成与人手相近的动作.     

气动肌肉驱动的柔顺机器人操作手的设计和实现

以气动肌肉为主要驱动器,设计了一个柔顺机器人操作手,在腕部和手部两个不同的关节,使用了两种不同型号的气动肌肉,分别采取了两种不同的传动方式．给出了腕部俯仰关节的位置控制策略．建立了手指的静力学模型,以此为基础,分析了气动肌肉的输入压力与指端夹持力的关系．实验结果表明,该机器人操作手可实现对物体安全、柔顺的抓取操作．     

形状记忆合金丝编织网气动肌肉机构及其阻抗控制

气动肌肉是仿生机器人研究的重点,为此,设计了形状记忆合金丝编织网气动肌肉机构.通过等效气缸和等效动力学分析,建立了输出力模型,设计了含位置PID内环的阻抗控制,并建立了阻抗模型,通过拉氏变换和频域分析给出了稳定条件.理论分析表明,合金丝的收缩可增大气动肌肉的输出力和调节刚度.在Matlab上开展阻抗参数对柔顺性影响的仿真实验,结果表明刚度对于接触力影响最大,阻抗控制可实现接触力和位置的协调控制.     

气动人工肌肉拮抗关节的力与刚度独立控制

针对柔性仿生关节难以实现力与刚度独立控制的问题,建立了一种新的气动人工肌肉等效弹簧模型及关节力和刚度模型,设计了一种双输入双输出滑模控制器,来实现对气动人工肌肉拮抗关节力与刚度的独立控制．最后,搭建了气动人工肌肉驱动的拮抗关节实验平台,在关节位置固定和开放两种状况下进行了实验研究,验证所提方法的有效性;在不同负载情况下进行了对比实验,验证所提方法的通用性．所提出的建模和控制方法综合考虑了仿生关节位置、力和刚度相对独立控制,在机器人与人或环境互相作用的场合有很好的应用前景．     

一种基于气动柔性驱动器的仿人机械手设计

为了提高柔性机械手结构刚性，保证其柔顺性以及实现灵巧运动，本文基于柔性驱动器技术，分析人手的外形、结构和运动特点，采取以气动柔性驱动器作为驱动关节的驱动方式，再结合刚性机械结构，设计出一种具有气动柔性手指、拇指对掌关节、刚性掌部的仿人机械手，并对其进行了姿态及抓握实验。实验结果表明，该仿人机械手具有良好的灵巧性和稳定的抓取能力。     

气动人工肌肉驱动的肘关节辅助机器人迟滞补偿

面向上肢康复与辅助运动,研制了一款基于气动人工肌肉(PAM)柔顺驱动的肘关节辅助机器人.气动人工肌肉的迟滞非线性极大降低了系统的运动精度.常见的基于离线辨识的迟滞补偿方法不能很好地适应系统状态的变化.本文提出了一种将直接逆模型法与改进的自适应投影(MAP)算法相结合的自适应迟滞补偿策略:基于直接逆模型法,使用Prandtl-Ishlinskii模型创建系统的逆迟滞模型,并以该模型为迟滞补偿器;使用MAP算法实现逆迟滞模型参数的在线辨识.这种方法无须离线建模与求逆,且无须针对不同的轨迹调节控制器参数.实验结果表明,与PID(比例-积分-微分)控制器与自适应投影(AP)算法相比,该方法有效地补偿了系统的迟滞,暂态过程的调节时间与超调量明显优于前面2种方法,闭环系统能够很好地跟踪阶跃与幅值衰减的正弦信号等不同类型的运动轨迹.     

采用扰动估计的气动人工肌肉系统非线性控制

气动人工肌肉系统凭借其材质轻便、输出力大及柔顺性好等优势, 其运动控制研究近年来逐渐成为热点问题. 然而, 气动人工肌肉(pneumatic artificial muscle, PAM)系统所固有的特性(如迟滞、蠕变、非线性时变等), 为其控制方法设计与实现带来了挑战. 考虑到实际工作过程中, 系统往往遭受未知干扰的影响, 本文针对气动人工肌肉系统, 提出了一种基于干扰估计的非线性控制策略, 可在系统存在持续不确定干扰的情况下, 在线进行扰动抑制, 实现精确的跟踪控制. 具体而言, 本文先通过模型变换, 将系统不确定性、未建模动态、外部扰动等处理成集总扰动的形式. 随后, 结合自适应更新律及正则化最小二乘算法, 在线估计未知系统参数及扰动; 在精确扰动代数估计的基础上, 通过所提基于干扰估计的非线性控制器, 消除未知扰动对系统造成的影响, 并确保跟踪误差收敛至零. 此外, 经稳定性分析证明了跟踪误差的渐近收敛性. 最后, 通过硬件实验验证了本文方法的有效性及鲁棒性.     

Advantages of flexible musculoskeletal robot structure in sensory acquisition

Morphological computation is the concept for which a well-designed hardware can bear part of the computational cost required for robot??s control and perception. So far, many musculoskeletal robots have been developed by taking inspiration from human??s one and shown superior motion performances. The use of pneumatic artificial muscles (PAMs) has been the key to realize these high performance. Additionally, PAMs have the possibility of being used as sensors for environmental information because they are flexible and backdrivable. In this research, we focus on clarifying how PAMs can contribute to morphological computation of robots driven by these actuators. In particular, we propose an analysis method based on transfer entropy and apply this method to the experimental data acquired by a musculoskeletal robot that opens a door.     

模块化可重构机器人动力学研究进展

模块化可重构机器人由于其构型多变,运动形式丰富等特点,可以在非结构化环境或未知环境中执行任务,在最近几年迅速成为机器人研究领域的前沿和热点. 模块化可重构机器人在军事、医疗、教育等众多工程领域具有广泛的应用前景,其典型代表包括仿生多足模块化机器人、模块化可重构机械臂、晶格式模块化机器人等. 模块化可重构机器人丰富的构型设计、多样的连接特征、不断拓展的应用范围,给动力学建模与控制带来了很多挑战和机遇. 本文首先阐述了模块化可重构机器人的研究背景和意义,并概述了其构型分类与设计、构型描述与运动学建模方法.随后,本文系统回顾了模块化可重构机器人动力学研究中相关问题的最新进展,包括：(1)系统整体动力学建模;(2)结合面以及对接机构动力学建模;(3)基于动力学模型的控制方法. 本文最后提出了模块化可重构机器人动力学研究中若干值得关注的问题.     

柔性机器人的动力学建模及其控制*

本文首先综述了近年来在柔性机器人动力学建模方面所取得的进展，着重介绍了目前较常见的几种建模方法和模型，同时对柔性机器人的控制问题进行了评述，指出了今后研究的方向。     

Design and control of a novel variable stiffness soft arm

Soft robot arms possess such characteristics as light weight, simple structure and good adaptability to the environment, among others. On the other hand, robust control of soft robot arms presents many difficulties. Based on these reasons, this paper presents a novel design and modeling of a fuzzy active disturbance rejection control (FADRC) controller for a soft PAM arm. The soft arm comprises three contractile and one extensor PAMs, which can vary its stiffness independently of its position in space. Force analysis for the soft arm is conducted, and stiffness model of the arm is established based on the relational model of contractile and extensor PAM. The accuracy of stiffness model for the soft arm was verified through experiments. Associated to this, a controller based on the fuzzy adaptive theory and active disturbance rejection control (ADRC), FADRC, has been designed to control the arm. The fuzzy adaptive theory is used to adjust the parameters of the ADRC, the control algorithm has the ability to control stiffness and position of the soft arm. In this paper, FADRC was further verified through comparative experiments on the soft arm. This paper reinforces the hypothesis that FADRC control, as an algorithm, indeed possesses good robustness and adaptive abilities.     

Active Vibration Control of Flexible Robots Using Virtual Spring-damper Systems

When using robots for heavy loads and huge operating ranges, elastic deformations of the links have to be taken into account during modeling and controller design. Whereas for conventional rigid multilink industrial robots modeling can schematically be done by standard techniques, it is a massive problem to obtain an accurate analytic model for multilink flexible robots. But an accurate analytic model is essential for most modern controller design techniques, and modeling errors can lead to instability of the controlled system due to spillover since the eigenvalues of the system are only slightly damped. A new approach to active damping control for flexible robots is presented in this paper where the actuators act like virtual spring-damper-systems. As the spring-damper-element is a passive energy dissipative device, it will never destabilize the system and thus the control concept will be very insensitive to modeling errors. Basically, the two parameters, spring stiffness and damping constant of this system, are arbitrary and model independent. To satisfy performance requirements they are adjusted using knowledge of the system model. The more it is known about the system model, the better these parameters may be adjusted. The new input of the controlled system is a virtual variation of the spring base. The paper illustrates this technique with the help of a simple and easy to model one link flexible robot which is also available as a real laboratory testbed.     

面向对象软件柔性的度量

为促进柔性软件的开发和研究,在总结柔性研究的基础上,通过分析柔性软件的特征提出了新的软件柔性的定义,并结合面向对象的技术给出了面向对象的软件柔性度量模型,该模型包括有效适应性、易用性、响应速率和成本比率4个侧面。为了使度量客观、具有操作性,对每一个侧面又进一步细化为若个要素,并具体定义了每一个要素的度量方法。     

Recent progress on programming methods for industrial robots

Although an automated flexible production cell is an intriguing prospect for small to median enterprises (SMEs) in current global market conditions, the complexity of programming remains one of the major hurdles preventing automation using industrial robots for SMEs. This paper provides a comprehensive review of the recent research progresses on the programming methods for industrial robots, including online programming, offline programming (OLP), and programming using Augmented Reality (AR). With the development of more powerful 3D CAD/PLM software, computer vision, sensor technology, etc. new programming methods suitable for SMEs are expected to grow in years to come.     

A distributed parameter model for the dynamics of flexible-link robots

In this paper a model is developed for kinematic and dynamic analysis of flexible robots undergoing general three-dimensional motion. For modeling robotic links, distributed mass and flexibility are considered without discretization. Some modeling issues are discussed, and parameters characterizing the real design of a robot are introduced into the analysis. The concept of a fictitious rigid link is presented to consider the rigid body motion of a link separately, and to account for possibly complex link shapes. Based on Jourdain's principle, an alternative formulation is proposed to derive the dynamic equations of flexible robots. The equations of motion are developed and analyzed in detail. The vibrations of links are described by linear, inhomogeneous partial differential equations, with homogeneous, nonlinear, time-dependent boundary conditions. © 1998 John Wiley & Sons, Inc.     

Control circuits simplification and computer programs design on bipedal robot

This study is expected to provide the best design of bipedal robot, which will help widen the application in the future. A new design system is presented through simplification of the control circuit, and the design of computer programs not only lowers the research barriers of the robots but also decreases the development costs. This design system can be used for various operations of manufacturing processes to make up the shortages of the flexibility for the robots. In recent years, the progress in electronics and the control technology has made the robots useful not only for dangerous and automatic tasks, but also for advanced and friendly people service. Thus, the robots have been used in the factories for automation and towards the general use in regular life. Of all robots, the bipedal robot attracts the most attention for its humanoid outlook, user-friendly design, and artificial intelligence for the human society. Many bipedal robots are developed to satisfy consumers’ needs. The control circuits and the program design are the key issues to make the bipedal robots. In this study, a synchronous robot controller for 31°-axis freedom is developed. The authors also equip a memory in the hardware architecture to store all moving commands of the bipedal robot. In terms of internal programs, the authors develop a human interface that synchronizes the movement of the robot and collects the pace data of the robot. The authors use the statistical method to analyze the data and establish a database of the robot's movement. With the database, one can finally drive the robot to walk and generate the pace design of the bipedal robots.     

布料仿真建模研究进展

布料仿真一直是计算机动画中的研究热点与难点,对提高计算机动画质量以及用户体验具有重要意义,布料是一种非常经典的柔性材料物体,遍布于人们的日常生活中。虚拟世界中虚拟角色强烈的视觉真实感主要来源于逼真的虚拟人物的服装动画,这在很大程度上可以增强用户的体验感,在游戏娱乐、电影电视和动画制作等领域有着十分广泛的应用前景。布料仿真的质量与速度直接决定了计算机动画的整体水平,而布料的模拟水平则起着至关重要的作用。随着计算机软硬件的不断发展和计算机动画市场需求的提高,对布料仿真建模方法的研究受到越来越多的关注,布料仿真建模方法也因此有了较大发展。本文通过回顾布料仿真建模方法的相关工作,对国内外方法的研究进展进行综述,从布料仿真中数值积分方法的改进、多分辨率网格的改进和机器学习方法的使用等方面对布料仿真方法的发展进行简要阐述,并根据不同方法在布料模拟应用上的特性,对几大类改进方法进行了相应的总结与展望。同时选取几种算法进行对比,并给出建议。