Illumination Adaptive Identification Algorithm of a Reconfigurable Modular Robot

Reconfigurable modular robots feature high mobility due to their unconstrained connection manners.Inspired by the snake multi-joint crawling principle,a chain-type reconfigurable modular robot(CRMR)is designed,which could reassemble into various configurations through the compound joint motion.Moreover,an illumination adaptive modular robot identification(IAMRI)algorithm is proposed for CRMR.At first,an adaptive threshold is applied to detect oriented FAST features in the robot image.Then,the effective detection of features in non-uniform illumination areas is achieved through an optimized quadtree decomposition method.After matching features,an improved random sample consensus algorithm is employed to eliminate the mismatched features.Finally,the reconfigurable robot module is identified effectively through the perspective transformation.Compared with ORB,MA,Y-ORB,and S-ORB algorithms,the IAMRI algorithm has an improvement of over 11.6%in feature uniformity,and 13.7%in the comprehensive indicator,respectively.The IAMRI algorithm limits the relative error within 2.5 pixels,efficiently completing the CRMR identification under complex environmental changes.

ANALYSIS OF TIPOVER STABILITY FOR NOVEL SHAPE SHIFTING MODULAR ROBOT

A novel three-module robot has been introduced. It can change its configuration to adapt to the uneven terrain and to improve its tipover stability. This three-module tracked robot has three kinds of symmetry configuration. They are line type, triangle type, and row type. After the factors and the countermeasures of mobile robot＇s tipover problem are analyzed, stability pyramid and tipover stabil-ity index are proposed to globally determinate the mobile robot＇s static stability and dynamic stability. The shape shifting robot is tested by this technique under the combined disturbance of pitch, roll and yaw in simulation. The simulation result shows that this technique is effective for the analysis of mobile robot＇s tipover stability, especially for the reconfigurable or shape shifting modular robot. Experiments on three symmetry configurations are made under unstructured environments. The environment experiment shows the same result as that of the simulation that the triangle type configuration has the best stability. Both simulation and experiment provide a valid reference for the reconfigurable robot＇s potential application.

Three-dimensional Construction and Omni-directional Rolling Analysis of a Novel Frame-like Lattice Modular Robot

Lattice modular robots possess diversity actuation methods, such as electric telescopic rod, gear rack, magnet, robot arm, etc. The researches on lattice modular robots mainly focus on their hardware descriptions and reconfiguration algorithms. Meanwhile, their design architectures and actuation methods perform slow telescopic and moving speeds, relative low actuation force verse weight ratio, and without internal space to carry objects. To improve the mechanical performance and reveal the locomotion and reconfiguration binary essences of the lattice modular robots, a novel cube-shaped, frame-like, pneumatic-based reconfigurable robot module called pneumatic expandable cube（PE-Cube） is proposed. The three-dimensional（3D） expanding construction and omni-directional rolling analysis of the constructed robots are the main focuses. The PE-Cube with three degrees of freedom（Do Fs） is assembled by replacing the twelve edges of a cube with pneumatic cylinders. The proposed symmetric construction condition makes the constructed robots possess the same properties in each supporting state, and a binary control strategy cooperated with binary actuator（pneumatic cylinder） is directly adopted to control the PE-Cube. Taking an eight PE-Cube modules＇ construction as example, its dynamic rolling simulation, static rolling condition, and turning gait are illustrated and discussed. To testify telescopic synchronization, respond speed, locomotion feasibility, and repeatability and reliability of hardware system, an experimental pneumatic-based robotic system is built and the rolling and turning experiments of the eight PE-Cube modules＇ construction are carried out. As an extension, the locomotion feasibility of a thirty-two PE-Cube modules＇ construction is analyzed and proved, including dynamic rolling simulation, static rolling condition, and dynamic analysis in free tipping process. The proposed PE-Cube module, construction method, and locomotion analysis enrich the family of the lattice modular robot and provide the instruction to design the lattice modular robot.

Metamorphic Algorithm of Self-reconfigurable Modular Robotic System

A self-reconfigurable robot is a non-linear complex system composed of a large number of modules. The complexity caused by non-linearity makes it difficult to solve the problem of module motion planning and shape-changing control with the traditional algorithm. In this paper, a full-discrete metamorphic algorithm is proposed. The modules concurrently process the local sensing information, update their eigenvector, and act by the same predetermined logical rules. Then a reasonable motion sequence for modules and the global metamorphosis can be obtained. Therefore, the complexity of metamorphic algorithm is reduced, the metamorphic procedure is simplified, and the self-organizing metamorphosis can be obtained. The algorithm cases of several typical systems are studied and evaluated through simulation program of 2-D planar homogeneous modular systems.

Center-configuration selection technique for the reconfigurable modular robot

The reconfigurable modular robot has an enormous amount of configurations to adapt to various environments and tasks. It greatly increases the complexity of configuration research in that the possible configuration number of the reconfigurable modular robot grows exponentially with the increase of module number. Being the initial configuration or the basic configuration of the reconfigurable robot, the center-configuration plays a crucial role in system＇s actual applications. In this paper, a novel center-configuration selection technique has been proposed for re- configurable modular robots. Based on the similarities between configurations＇ transformation and graph theory, configuration network has been applied in the modeling and analyzing of these configurations. Configuration adjacency matrix, reconfirmation cost matrix, and center-configuration coefficient have been defined for the configuration network correspondingly. Being similar to the center-location problem, the center configuration has been selected according to the largest center-configuraUon coefficient. As an example of the reconfigurable robotic system, AMOEBA-I, a three-module reconfigurable robot with nine configurations which was developed in Shenyang Institute of Automation （SIA）, Chinese Academy of Sciences （CAS）, has been introduced briefly. According to the numerical simulation result, the center-configuration coefficients for these nine configurations have been calculated and compared to validate this technique. Lastly, a center-configuration selection example is provided with consideration of the adjacent configurations. The center-configuration selection technique proposed in this paper is also available to other reconfigurable modular robots.

Configuration analysis of a chain-type reconfigurable modular robot inspired by normal alkane

Normal alkane is an unbranched alkane whose structural formula is H–CH2–CH2–…–CH2–…–CH2–H,which can be regarded as a reconfigurable chain-type structure composed of–CH2–modules.Inspired by normal alkane,a normal-alkane-like reconfigurable modular robot (NAR) is proposed.The module consists of two differential gear trains mounted orthogonally.Each differential gear train contains two input degrees of freedom and two output degrees of freedom.Due to the genderless interface design,multiple modules can be assembled into chain-type configuration.With the genderless interfaces and flexible degrees of freedom,NAR can be reconfigured into different dimensions of spatial configuration.The bond matrix is used to describe the configuration,which represents the bond attitude of the adjacent connected modules.In addition,full interconnected geometric feature (FIGF) algorithm is proposed for non-isomorphic configuration enumeration and judgment.The configurations with three modules are simulated and the results verify the feasibility of the algorithm.Finally,a prototype with three modules is fabricated and the configuration motion sequence is demonstrated.

Self-assembly control and experiments in swarm modular robots

This paper presents a self-assembly control strategy for the swarm modular robots. Simulated and physical experiments are conducted based on the Sambot platform, which is a novel self-assembly modular robot having the characteristics of both the chain-type and the mobile self-reconfigurable robots. Multiple Sambots can autonomously move and connect with one another through self-assembly to form robotic organisms. The configuration connection state table is used to describe the configuration of the robotic structure. A directional self-assembly control model is proposed to perform the self-assembly experiments. The self-assembly process begins with one Sambot as the seed, and then the Docking Sambots use a behavior-based controller to achieve connection with the seed Sambot. The controller is independent of the target configuration. The seed and connected Sambots execute a configuration comparison algorithm to control the growth of the robotic structure. Furthermore, the simul- taneous self-assembly of multiple Sambots is discussed. For multiple configurations, self-assembly experiments are conducted in simulation platform and physical platform of Sambot. The experimental results verify the effectiveness and scalability of the self-assembly algorithms.

A mobile self-reconfigurable robot based on modularity

A novel mobile self-reconfigurable robot is presented.This robot consists of several independentunits.Each unit is composed of modular components including ultrasonic sensor,camera,communica-tion,computation,and mobility parts,and is capable of simple self-reconfiguring to enhance its mobilityby expanding itself.Several units can not only link into a train or oilier shapes autonomously via cameraand sensors to be a united whole robot for obstacle clearing,but also disjoin to be separate units undercontrol after missions.To achieve small overall size,compact mechanical structures are adopted in modu-lar components design,and a miniature advanced RISC machines(ARM)based embedded controller isdeveloped for minimal power consumption and efficient global control.The docking experiment betweentwo units has also been implemented.

Design and implementation of a modular self-reconfigurable robot

A novel modular self-reconfigurable robot called UBot is presented.This robot consists of severalstandard modules.The module is cubic structure based on double rotational DOF,and has four connect-ing surfaces that can connect to adjacent modules.A hook-type mechanism is designed,which can quick-ly and reliably connect to or disconnect from adjacent module.This mechanism is self-locking after con-nected,and energy-saving.To achieve small overall size and mass,compact mechanical structures andelectrical systems are adopted in modular design.The modules have embedded power supply and adoptwireless communication,which can avoid cable-winding and improve flexibility of locomotion and self-re-configuration.A group of UBot modules can adapt their configuration and function to the changing envi-ronment without external help by changing their connections and positions .The basic motion and self-re-configuration are proposed,and the experiments of worm-like locomotion are implemented.

基于多人零和博弈的模块化机器人系统近似最优控制

提出一种基于多人零和博弈的模块化机器人(Modular Robot Manipulators, MRMs)系统近似最优控制方法。建立了具有交联耦合(Interconnected Dynamic Couplings, IDC)的模块化机器人系统动力学模型。将机器人系统的控制律和IDC效应作为零和博弈的参与者,MRM系统的最优跟踪控制问题转化为多人零和博弈问题。根据自适应动态规划(Adaptive Dynamic Programming, ADP)算法,通过建立评判神经网络求解哈密顿-雅克比-埃塞克斯(Hamilton-Jacobi-Issacs, HJI)方程,推导出最优控制律。基于李雅普诺夫定理,证明了闭环机器人系统是渐近稳定的,最后通过实验验证了所提控制方法的有效性。

四自由度串联嫁接机器人架构约束模块识别可视化方法

为实现育苗嫁接的智能化与高效化,一类四自由度串联嫁接机器人的新结构被提出;针对其机械结构、时序控制、联动运行等复杂性,发展该类机器人架构约束下的模块识别可视化方法及设计流程。首先,构建考虑特定架构约束下机器人的设计结构矩阵(DSM),并采用大型社区快速展开算法(LOUVAIN算法)实现对机器人架构模块的预划分;其次,采用改进遗传算法(AGA)对DSM进行聚类,获得多组高模块度的划分结果,由此形成成组可能性矩阵(GLM),并将其对角化得到对角GLM(DGLM);最后,提出针对DGLM的可视化策略并完成着色处理,实现对最优模块划分方案的辨识。结果显示:四自由度串联嫁接机器人可分解为较独立的7大模块,模块度可达0.782。

Improving the Use of Robotic Welding of Aluminum Boats through Modularization

The level of automation in the manufacture of recreational aluminum boats is very low. Robotized welding is rarely utilized, although it is commonly considered as the most effective way to reduce costs and increase competitiveness. A reason for the under-exploitation of robotics can be found in the construction of aluminum boats;boat models and their detailed structures are almost without exception individual pieces. A new stiffener structure for an aluminum recreational boat hull is developed in this work. Construction of the stiffener as a module allows exploitation of the advantages of modularization. The number of different parts is reduced and the structure simplified improves the applicability of robotic welding and provides benefits accruing from mass production. The same module can be used in several boat models. The modularity also makes it possible to use the same advanced robot welding fixture for a variety of boat models.

模块化作业爬壁机器人设计与分析

为解决传统爬壁机器人在海上风电塔筒立面的作业效率低下和吸附力不足问题,根据模块化设计方法,提出一种可同时用于表面漆膜检测及运维的模块化履带式爬壁机器人。本文详细介绍作业机器人的结构组成及原理,为防止机器人发生滑落和倾覆现象,对其进行力学分析;构建间隙式永磁吸附模型,利用Maxwell软件与传统磁路设计进行参数化仿真对比,并分析气隙和壁厚对机器人吸附力的影响;通过样机平台模拟实验和真实作业,表明机器人能以稳定运动姿态实现塔筒高空及水下作业,验证了其模块化作业的可行性,并同时具备较强的吸附能力和越障能力。

模块化轮式全向移动机器人底盘的设计

针对常见农业轮式机器人底盘存在的运动灵活性不高、所需运动空间较大等问题,设计了模块化轮式全向移动机器人底盘。采用四轮支撑方案,通过两个具备独立转向驱动功能的模块化轮组配合两个万向轮实现底盘的灵活全向移动。建立运动学模型,得到各电机输入转速与底盘运行速度的关系。建立动力学模型,通过分析万向轮对驱动轮驱动力矩的影响,修正驱动力矩表达式。通过对驱动力矩的动态调整和控制,有效减少底盘运动打滑现象。通过仿真及样机试验,对底盘的直行、侧行、原地旋转进行运动控制,验证底盘稳定可靠的全向移动性。

小型台式点样机器人THU-Biorobot Ⅲ的研制与开发

介绍了小型台式点样机器人THU-Biorobot Ⅲ的功能、机械结构、控制系统以及用户软件设计.THU-Biorobot Ⅲ基于模块化思想设计,包括内嵌式环境控制模块、样品盒更换模块、点样针清洗干燥模块等.THU-Bioro-bot Ⅲ利用接触式点样来制备微阵列生物芯片.

模块化管道焊接机器人结构设计与分析

针对城市供水管网铺设时操作空间狭小、人工焊接效率低、质量不稳定等问题,设计一种模块化管道焊接机器人。采用模块化设计方法,完成焊接机器人的机械结构设计,主要包括焊接行走底盘、焊枪姿态调整机构和可调柔性导轨3部分。运用D-H参数法建立机器人运动学方程,基于蒙特卡罗法对该机器人的可视化工作空间进行仿真分析。最后进行模块化管道自动焊接工艺实验和施工现场应用。实验结果和施工现场应用结果表明:该机器人能够完成对应壁厚钢管的全位置焊接任务,焊接过程稳定且焊缝成形良好。

输电线模块化双臂带电作业机器人作业空间与轨迹规划仿真

输电线路带电作业机器人可以辅助甚至替代人工实现输电线路的带电巡视和作业,然而机器人体积庞大,在野外复杂作业环境下运输十分不便,因此针对输电线路多种检修作业任务设计了一种模块化双臂带电作业机器人。模块化设计可以实现机器人的快速拆装,解决机器人运输难题。针对典型金具检修作业任务,对机器人机械臂进行运动学建模,并基于该模型对机械臂末端进行作业空间与运动轨迹规划仿真,仿真结果验证了双臂带电作业机器人系统设计的可行性和有效性。

模块化机器人结构设计及运动特性分析

针对传统机器人关节在运动过程中的偏转角度、俯仰承载能力受限问题,以提高机器人偏转、俯仰运动能力为目标,提出单电机驱动双轴式、具有大偏转角度特性的偏转关节模块,和基于平行四边形结构及弹簧部件、具有低功耗高承载能力特性的俯仰关节模块,进行了偏转模块、俯仰模块运动特性分析。建立基于新型模块的机器人运动学模型,对比分析相同尺寸及工作条件下新型机器人与基于传统关节机器人的工作空间,结果表明:同等条件下新型机器人工作空间明显大于传统机器人结构,所提出新型关节模块可有效提升机器人运动灵活性。

基于模块化的小体量割草机器人设计

为实现割草工作的高效化、应用场景的广泛化,将模块化设计引入割草机器人,并针对当前割草机机型大、易污染等不足进行小体量优化设计。通过分析机器人的工作场景,确定基本的设计结构和控制模块,进而实现割草机器人的总体设计。测试割草机器人的系统性能,测试结果与预期相差较小,证明割草机器人能够正常完成割草工作,且能够根据要求灵活更换刀盘,升降结构能够灵活运作,提高了割草工作的效率。文章研究为割草机器人的设计提供了可行的思路,具有一定的参考价值。