SIA OpenIR  > 机器人学研究室
水下滑翔蛇形机器人的步态研究
Alternative TitleResearch on Gaits of an Underwater Gliding Snake-like Robot
唐敬阁1,2
Department机器人学研究室
Thesis Advisor张艾群 ; 李斌
Keyword水下滑翔蛇形机器人 滑翔运动 混合驱动滑翔运动 多功能伸缩模块 动力学建模和运动控制
Pages106页
Degree Discipline机械电子工程
Degree Name博士
2020-11-27
Degree Grantor中国科学院沈阳自动化研究所
Place of Conferral沈阳
Abstract基于仿生学的水下蛇形机器人可以实现多种蛇形游动步态,机动性强,但是续航能力有限;净浮力驱动的水下滑翔机通过滑翔运动可以实现远距离的航行,续航时间较长;因此,把滑翔运动引入到水下蛇形机器人中,可以得到一种新型的水下滑翔蛇形机器人,它结合了水下蛇形机器人和水下滑翔机的优点,可以实现蛇形游动和滑翔运动,解决了水下蛇形机器人续航能力差的问题,满足了水环境监控、水质监测以及军事等方面对机器人续航能力和机动性能的需求。水下滑翔蛇形机器人具有净浮力驱动、多关节驱动以及混合驱动多种模式,在结构设计、建模和运动分析等方面与传统的水下滑翔机和水下蛇形机器人有所差异。由于现有研究中并无适用于水下滑翔蛇形机器人的净浮力驱动系统,也缺乏对多关节和净浮力混合驱动模式的理论基础,因此本文以2017国家重点研发计划“软体、变形体、刚柔耦合新型仿生驱动机构的设计与优化理论”为依托,对水下滑翔蛇形机器人的机构设计与运动控制方法展开研究。具体研究内容包括:(1)实验平台设计与机理验证:为了实现滑翔运动,设计可以实现净浮力调节和俯仰力矩调节的伸缩模块,结合转动模块、机翼和控制系统,完成第一代实验平台的搭建,通过实验证明该机械结构可以实现下沉、上浮和俯仰角调整,验证了平台的有效性。由于一代机器人在防水性能、水动力特性等方面有所不足,因此对结构参数、密封方式、模块结构等方面进行优化,搭建第二代实验平台,通过实验对蛇形游动、净浮力驱动滑翔运动和混合驱动滑翔运动进行了验证。(2)净浮力驱动滑翔运动的动力学建模:本文对净浮力驱动的滑翔运动进行了动力学模型推导。为了降低建模难度,假设转动模块之间没有相对转动,并且把机器人看做一个刚体。基于动量定理和动量矩定理,结合水动力模型的分析,推导滑翔运动的三维动力学模型,考虑期望的滑翔运动在垂直面上,将其简化获得二维动力学模型。水动力系数是仿真分析中的重要参数,通过计算流体力学 (Computational Fluid Dynamics,CFD) 方法,对机器人进行水动力分析,通过曲线拟合获得水动力系数。为了实现期望的滑翔运动,基于二维动力学模型,对系统的平衡状态进行计算分析,获得系统状态量和输入量之间的变化关系,有助于指导期望滑翔运动的选择。(3)净浮力驱动滑翔运动的优化控制:针对滑翔运动的动力学模型,对其在平衡点处进行线性化,通过设计线性二次型调节器 (Linear Quadratic Regulator,LQR),使闭环系统在平衡点附近渐近稳定。为了提高系统的跟踪精度,增强系统对扰动的鲁棒性,设计线性二次型积分器 (Linear Quadratic Integral Regulator,LQI)。仿真证明LQR和LQI方法均能实现系统的渐近稳定和对输入扰动的抑制,另外LQI对参数扰动具有渐近调节能力。为了充分考虑系统的非线性项,首先对非线性动力学模型进行反馈线性化;然后采用基于趋近律的滑模控制 (Sliding Mode Control,SMC) 方法设计控制器;由于控制器需要所有系统状态量信息,采用无迹卡尔曼滤波器 (Unscented Kalman Filter,UKF) 对难以直接测量的运动速度进行估计。仿真验证了由UKF和SMC构成的闭环系统的有效性。(4)混合滑翔运动的动力学建模与运动控制:本文针对净浮力和转动关节共同驱动的混合滑翔运动展开研究。把混合滑翔运动分解为水平面的蛇形游动和垂直面的滑翔运动,两个平面在相交轴线上的运动是耦合的,因此把滑翔运动在该轴的外力分量叠加到蛇形游动在该轴的外力中,从而获得混合滑翔运动的动力学模型。基于动力学模型,对系统输入和被控状态进行解耦分析,设计PID控制器,实现对运动速度、姿态角和关节角的跟踪控制。考虑由未建模动态和噪声等引起的系统扰动,基于反步控制和自抗扰控制方法设计具有一定抗扰动能力的非线性控制系统 (Nonlinear Control,NC),仿真验证非线性控制系统相比PID系统具有更好的控制品质。通过设计合适的净浮力驱动系统、研究净浮力驱动滑翔运动以及混合驱动滑翔运动,不仅解决了水下滑翔蛇形机器人现有研究中存在的关键问题,丰富了其研究理论,也为其在水环境中的实际应用提供了理论依据。
Other AbstractAn underwater snake-like robot based on bionics can perform a variety of snake-like swimming gaits, with strong mobility but limited endurance. A net buoyancy-driven underwater glider can achieve long-distance navigation through gliding motion and have a long endurance. Therefore, introducing gliding motion into the underwater snake-like robot, a novel underwater gliding snake-like robot can be obtained. Combining the advantages of the underwater snake-like robot and the underwater glider, it can realize snake-like swimming and gliding motion, which solves the problem of poor endurance for the underwater snake-like robots and meets the requirements for endurance and maneuverability of robots in shallow water monitoring, water detection, and military. The underwater gliding snake-like robot has net buoyancy driving, multi-joint driving and hybrid driving modes, which is different from the traditional underwater glider and underwater snake-like robot in terms of structural design, modeling and motion analysis. Since there is no net buoyancy driving system suitable for the underwater gliding snake-like robot in the existing research, and there is no theoretical foundation for the multi-joint and net buoyancy hybrid driving mode, this paper relies on the 2017 National Key Research and Development Project of China “Design and optimization theory of novel bionic driving mechanisms for soft body, deformable body and rigid-flexible coupling”, and carries out research on the mechanism design and the motion control methods for the underwater gliding snake-like robot. Specific research contents include: (1) Experiment platform design and mechanism verification: In order to achieve gliding movement, a telescopic module that can adjust net buoyancy and pitch moment is designed. Combining with the rotate module, wings and control system, the first generation experiment platform is developed. Experiments prove that the mechanical structure can accomplish sinking, ascending and adjusting pitch angle. Moreover, the effectiveness of the platform is verified. As the first generation is inadequate in terms of waterproof performance and hydrodynamic characteristics, the structural parameter, sealing method, module structure, etc. are optimized to complete the construction of the second generation experiment platform. The snake-like swimming, net buoyancy-driven gliding movement and hybrid-driven gliding movement are verified through experiments. (2) Dynamic modeling of gliding movement driven by net buoyancy: This paper deduces the dynamic model of the gliding motion driven by net buoyancy. To reduce the difficulty of modeling, it is assumed that there is no relative rotation between rotate module, and the robot is regarded as a rigid body. Based on theorem of momentum, theorem of momentum moment and analysis of hydrodynamic model, a three-dimensional (3D) dynamic model of the gliding motion is derived. Further, it is simplified to acquire a two-dimensional (2D) dynamic model for consideration of the desired gliding in the vertical plane. Hydrodynamic coefficients are important parameters in simulation analysis. Utilize computational fluid dynamics (CFD) method to carry out the hydrodynamic analysis, and then the hydrodynamic coefficients can be gained through curve fittings. To achieve the desired gliding movement, the equilibrium state of the system is calculated and analyzed on the basis of the 2D dynamic model, and the relationship between the system state and the system input is obtained, which helps to instruct the selection of the desired gliding state. (3) Optimal control of gliding movement driven by net buoyancy: For the dynamic model of the gliding motion, linearization is performed at the equilibrium point. By designing a linear quadratic regulator (LQR), the closed-loop system is asymptotically stable near the equilibrium point. In order to improve the tracking accuracy of the system and enhance the robustness of the system to disturbances, a linear quadratic integral regulator (LQI) is designed. Simulation confirms that both the LQR and the LQI methods can achieve the asymptotic stability of the system and the suppression of input disturbances. In addition, the LQI has the ability of asymptotic regulation to parameter disturbances. To take fully nonlinear terms of the system into consideration, the nonlinear dynamic model is first feedback linearized, and then the sliding mode control (SMC) method based on the reaching law method is used to design system controller. Since the controller requires all the system states, an unscented Kalman filter (UKF) is used to estimate the movement velocity that is difficult to measure directly. Simulation verifies the effectiveness of the closed-loop system composed of the SMC and the UKF. (4) Dynamic modeling and motion control of hybrid gliding movement: This paper studies the hybrid gliding movement driven by net buoyancy and rotate joints. The hybrid gliding is decomposed into the serpentine swimming in the horizontal plane and the gliding motion in the vertical plane. Because the motion of the two planes on the intersecting axis is coupled, the external force of gliding on this axis is superimposed on the external force of swimming on this axis. Then the dynamics of the hybrid gliding motion is obtained. According to the dynamic model, the system input and controlled state are decoupled, and a PID controller is designed. Tracking control of the gliding velocity, attitude angles and joint angles are realized. Considering the system disturbance caused by unmodeled dynamics and noise, a nonlinear control (NC) system with certain anti-disturbance ability is designed based on the backstepping method and active disturbance rejection control method. Simulation verifies that the NC system has better control quality than the PID system. By designing a suitable net buoyancy driving system, and studying the net buoyancy-driven gliding motion and the hybrid-driven gliding motion, not only the key problems in the existing research on the underwater gliding snake-like robot are solved, but also the research theory is enriched, and it also provides a theoretical foundation for the robot’s practical application in water.
Language中文
Contribution Rank1
Document Type学位论文
Identifierhttp://ir.sia.cn/handle/173321/27983
Collection机器人学研究室
Affiliation1.中国科学院沈阳自动化研究所
2.中国科学院大学
Recommended Citation
GB/T 7714
唐敬阁. 水下滑翔蛇形机器人的步态研究[D]. 沈阳. 中国科学院沈阳自动化研究所,2020.
Files in This Item:
File Name/Size DocType Version Access License
水下滑翔蛇形机器人的步态研究.pdf(6951KB)学位论文 开放获取CC BY-NC-SAApplication Full Text
Related Services
Recommend this item
Bookmark
Usage statistics
Export to Endnote
Google Scholar
Similar articles in Google Scholar
[唐敬阁]'s Articles
Baidu academic
Similar articles in Baidu academic
[唐敬阁]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[唐敬阁]'s Articles
Terms of Use
No data!
Social Bookmark/Share
All comments (0)
No comment.
 

Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.