Design of six-legged walking robot,Little Crabster for underwater walking and operation

This paper describes the development of a ground test robot platform to study a multi-legged walking robot capable of precise proximity exploration and operations under a shallow sea in the presence of a strong tidal current environment. For both underwater walking and complex operations, a six-legged robot that uses two legs as manipulators during underwater operations is proposed. The dimensions, joint structure, range of motion, and mass distribution of the robot are determined by considering biological data, and then suitable joint actuators are chosen through a simple force analysis. In addition, a main controller, a communication bus, motor controllers, sensors, and a battery are chosen to build the whole control system. The detailed design is performed using 2D/3D computer aided design (CAD) software, and the robot is finally built by machining the parts and assembling them. The degree of design completion is proved by basic walking experiments and future works are addressed.     

小课题、真制作、开展校内实践教学的探索

校内实践教学是融教、学、作为一体的重要途径，本文阐述了我校电子专业以小课题、真制作为宗旨，并把市场、学校、工厂结合在一起组织实践教学的一些方法，愿与同行同志进行交流，互相提高。     

A distributed perception infrastructure for robot assisted living

This paper presents an ambient intelligence system designed for assisted living. The system processes the audio and video data acquired from multiple sensors spread in the environment to automatically detect dangerous events and generate automatic warning messages. The paper presents the distributed perception infrastructure that has been implemented by means of an open-source software middleware called NMM. Different processing nodes have been developed which can cooperate to extract high level information about the environment. Examples of implemented nodes running algorithms for people detection or face recognition are presented. Experiments on novel algorithms for people fall detection and sound classification and localization are discussed. Eventually, we present successful experiments in two test bed scenarios.     

Pneumatic walking assistive device for use over long period

Humans can adapt to and effectively walk on different kinds of surfaces and in various environments, but fatigue is inevitable when walking or even just standing for long periods, especially when carrying heavy objects. Methods for assisting walking or standing work are in demand, but most research thus far has been focused on using electricity to implement both interlocking and assistive power; this approach has the drawback of high-energy consumption. Therefore, we previously developed a lightweight assistive device that stores part of the kinetic energy generated during the leg swing-to-leg contact phases, and uses this energy to effectively assist during the stance phase. The developed device comprises surge tanks, an air cylinder, and other components arranged in a simple configuration and interlocked with walking by using a simple sensing system, therefore, making it suitable for use over long periods. This paper presents experimental measurements of the assistive force generated using the proposed device when it is attached to human subjects. The measurements were conducted under predicted usages to evaluate the assistive performance of the proposed device, and the measurement results demonstrate its effectiveness.     

VFH*TDT (VFH* with Time Dependent Tree): A new laser rangefinder based obstacle avoidance method designed for environment with non-static obstacles

New modifications of VFH+ and VFH* (Vector Field Histogram) methods are presented in the paper. The features of the histogramic algorithms are generally improved and also using a potential of advanced sensors such as laser scanners is enabled. The main focus of the work is an introduction of modifications that provides collision-free navigation in environments with moving obstacles. For this purpose, a new approach in creating a look-ahead tree is proposed. All new modifications are analyzed and experimentally verified. The results obtained using conventional and modified methods have been compared. Experiments have demonstrated the validity and the technical feasibility of the proposed methods.     

Roombots: A hardware perspective on 3D self-reconfiguration and locomotion with a homogeneous modular robot

In this work we provide hands-on experience on designing and testing a self-reconfiguring modular robotic system, Roombots (RB), to be used among others for adaptive furniture. In the long term, we envision that RB can be used to create sets of furniture, such as stools, chairs and tables that can move in their environment and that change shape and functionality during the day. In this article, we present the first, incremental results towards that long term vision. We demonstrate locomotion and reconfiguration of single and metamodule RB over 3D surfaces, in a structured environment equipped with embedded connection ports. RB assemblies can move around in non-structured environments, by using rotational or wheel-like locomotion. We show a proof of concept for transferring a Roombots metamodule (two in-series coupled RB modules) from the non-structured environment back into the structured grid, by aligning the RB metamodule in an entrapment mechanism. Finally, we analyze the remaining challenges to master the full Roombots scenario, and discuss the impact on future Roombots hardware.     

Petri-net-based implementations for FIRA weightlifting and sprint games with a humanoid robot

In this paper, the Petri net-based wireless sensor node architecture (PN-WSNA) is used to control a humanoid robot to play weightlifting and sprint games in the FIRA HuroCup league. With the PN-WSNA approach, the control scenario and decision-making for playing weightlifting and sprint games can be modeled as a PN-WSNA model. The PN-WSNA inference engine is further used to interpret and execute the PN-WSNA model according to the sensor information from visual perception. Therefore, the implementation of playing weightlifting and sprint games is achieved in terms of the PN-WSNA model instead of native code. To verify the PN-WSNA-based implementation approach, an autonomous humanoid robot equipped with a camera and a single-board computer is used for experiments, where the camera is responsible for grabbing image frames; the single-board computer is responsible for visual localization; and the PN-WSNA models the execution and locomotion command generation. Finally, several PN-WSNA models for playing weightlifting and sprint games are proposed and the experimental results are demonstrated and discussed to validate the feasibility of applying the proposed PN-WSNA-based implementation approach.     

Environmental influences on indoor walking behaviours of assisted living residents

Regular walking behaviours can improve older people's physical, psychological and social health. This project examined the relationships between assisted living facilities’ design features and residents’ indoor walking behaviours through surveys and field evaluations. Surveys were conducted in 18 assisted living facilities in the US state of Texas. Researchers gathered information from 343 residents about their walking behaviours, participation in other activities, health and demographic status, and perceptions of the environment. Field evaluations were conducted to collect objective physical environment measures. Facility information was provided by the administrators. Multivariate hierarchical regression analysis showed significant influences of physical environments on indoor walking behaviours. Indoor recreational walking was related negatively to the number of stories of the building and positively to the perception of looped corridors. Different types of utilitarian walking, such as ‘walk to other activities’, ‘walk to front entry' and ‘walk to mailbox' were influenced by specific design features. The number of utilitarian walking types was marginally influenced by the number of stories of the building. These findings will help inform the design of activity-friendly assisted living facilities and the creation of health promotion programmes for frail older people.     

新型四足步行机器人串并混联腿的运动学分析

针对串联四足机器人行走惯量大,自重/载重比大的问题,提出一种新型串并混联四足步行机器人,并对该机器人的串并混联腿进行运动学分析。该机器人由一个运载平台和四条结构相同的串并混联腿组成,每条腿均由髋关节、大腿、小腿顺次连接构成,其中髋关节为3-RRR并联机构。以能耗最小姿态为最优姿态,基于矢量法求解了该串并混联腿的运动学正解和反解,利用MATLAB和ADAMS软件验证了正解和反解的正确性;基于矢量法和微分变换法求出了该混联腿的速度雅克比矩阵和加速度矩阵,分析了其奇异性,并利用MATLAB软件绘制出该腿的工作空间。结果表明:该腿在髋关节连杆直径d=22mm,大腿杆件直径D=50mm,膝关节转角θ4∈[105°,155°]时,工作空间呈球冠形,最大内接圆半径R=400mm,高度为H∈[500mm,900mm]。本研究对该新型串并混联四足步行机器人的刚度分析、动态性能、机构优化设计和系统控制等的进一步研究具有重要意义。