Function-oriented optimization design method for underactuated tendon-driven humanoid prosthetic hand

The loss of hand functions in upper limb amputees severely restricts their mobility in daily life. Wearing a humanoid prosthetic hand would be an effective way of restoring lost hand functions. In a prosthetic hand design, replicating the natural and dexterous grasping functions with a few actuators remains a big challenge. In this study, a function-oriented optimization design (FOD) method is proposed for the design of a tendon-driven humanoid prosthetic hand. An optimization function of different functional conditions of full-phalanx contact, total contact force, and force isotropy was constructed based on the kinetostatic model of a prosthetic finger for the evaluation of grasping performance. Using a genetic algorithm, the optimal geometric parameters of the prosthetic finger could be determined for specific functional requirements. Optimal results reveal that the structure of the prosthetic finger is significantly different when designed for different functional requirements and grasping target sizes. A prosthetic finger was fabricated and tested with grasping experiments. The mean absolute percentage error between the theoretical value and the experimental result is less than 10%, demonstrating that the kinetostatic model of the prosthetic finger is effective and makes the FOD method possible. This study suggests that the FOD method enables the systematic evaluation of grasping performance for prosthetic hands in the design stage, which could improve the design efficiency and help prosthetic hands meet the design requirements.     

Creative design of a wheel damping mechanism

The objective of this work is to provide a systematic method for the creation of all possible wheel damping mechanisms based on a parent mechanism. The original mechanism is generalized into a linkage type kinematic chain according to the rules defined. The self-assortment and the related assortments of this kinematic chain are derived by using the technqiue of number synthesis. These derived kinematic chains are respecialized, by applying the generalized rules backward based on some design constraints, to create a total of 98 new wheel damping mechanisms.     

基于功能-构造与实例的机构方案创新设计CAD

研究了机构设计的思维过程及机构表征的双重性,依据机构在大脑中的演变,计算机的信息处理特点和基于实例的设计方法,提出通过功能一构造的关联、参教化技术以及实例仿真等进行机构方案设计与创新的CAD方法.以连杆机构方案创新设计为例,实现了在人机交互环境下的智能化设计过程.对机构方案创新设计和计算机智能化设计过程研究有重要意义.     

一种肌电假手的自适应模糊控制方法

针对肌电假手的力控制问题,提出了一种基于肌电信号自适应学习的动作识别方法,同时结合模糊神经网络PID控制算法实现肌电信号对假手的控制.设计的肌电信号自适应学习动作识别方法在时域内进行,减小运算复杂度和计算量的同时保证了动作识别精度.采用模糊神经网络PID算法设计了假手握力控制器,在没有位置传感器的情况下保证了假手握力的控制精度.进行了肌电信号动作识别跟踪实验、假手握力跟踪实验、肌电信号控制假手抓取实验,实验结果证明了肌电信号自适应学习动作识别方法和模糊神经网络PID握力控制方法在肌电假手控制中的有效性.     

基于DSP的仿人形假手控制系统研究

为解决假肢手控制系统复杂等问题,将欠驱动技术应用到假肢手的机械结构设计中,整个假手由3个电机驱动,手指结构选用绳索滑轮驱动方式。开展了对机械系统原理和结构的分析,提出了基于DSP的结构简单、开发周期短、具有力反馈的运动控制系统,该控制系统用于驱动各手指动作。介绍了控制系统的硬件实现方法和软件控制流程,硬件主要包括电平转换和传感器信号处理电路,共有两种类型、11个传感器,可为假手自主抓取中的感觉反馈提供数据;软件主要涉及事件管理器、模数转换模块的应用。最后对假手中的压力传感器进行了标定,并进行了假手抓取试验。研究结果表明,基于力传感器反馈的控制策略使得假手能够实现稳定包络抓取。     

电脑刺绣机挑线机构的创新设计

以电脑刺绣机挑线机构为研究对象，设计出一种新型的电脑刺绣机挑线机构，推导了创新机构设计的理论方程，计算分析了创新机构的挑线运动规律，画出了创新机构的结构简图，所得结论可用于电脑刺绣机挑线机构的创新设计。     

基于超声信号的假手实时控制系统研究

假手控制方法是假肢技术研究的热点问题之一,研究者利用各种人体生理信号作为控制源,希望能够简单、方便、准确地操控多个自由度。本文在以前工作的基础上,研究用超声实时控制动力假手的新方法,设计了基于超声的假手控制系统,包括单通道超声收发和采集、假肢控制、信息处理与反馈等部分。基于该系统进行了正常人假手控制实验,探讨将超声信号作为假手控制源的可行性。实验结果表明单通道超声信号能连续控制假手的张开程度,为实现假手的抓握控制提供了一种简单有效的方式,具有良好的控制性能。这为进一步研制多通道超声控制多自由度假手提供了理论与实验基础。     

一种机器人特殊手部机构设计

介绍了一种抓取特殊曲面物体机器人手部机构,比较详细地说明了特殊手部对物体的接触力控制、定位、吸取、移动位姿保持、防落保护和定位放置的功能设计,还说明了吸取力的计算方法和特殊手部的主要气动控制线路的设计思路。经设计验证,满足使用要求。     

基于现代设计方法学的机械创新设计研究

机械产品设计一般要经过产品规划、原理方案设计、技术设计、施工设计、改进设计等几个阶段,根据这一过程,以现代设计方法为基础,以产品创新为目的,从输入产品的设计要求到最终输出产品的设计方案,分别研究了面向功能原理方案、基于人机工程学、基于智能化方法、基于反求工程的机械产品创新设计方法,旨在为深入研究实用的、符合工程设计要求的创新设计系统提供有益的参考.     

A dexterous robot hand with a bio-mimetic mechanism

This paper describes a development of bio-mimetic robot hand and its control scheme. This robot hand has four independently moving fingers, which are driven by four-coupled link mechanism with two linear actuators. By using the linear actuators, we make the hand similar to human hand in its structure and motion. The coupled link mechanism makes the hand compact in structure and efficient in power. The robot hand is designed considering the dexterity and the compact size suited for various tools and objects in daily life. The hand has tactile sensors mounted on the palm and the fingertips at each finger. With tactile sensor based feedback control and force closure method, the paper shows the control of the robot hand which is very stable in grasping and handling various objects.     

Design and analysis of a novel parallel mechanism for prosthetic knee wear test simulators

Using a parallel mechanism in the wear test simulators of prosthetic knees provides an easy access to the femoral and tibial components during tests. Moreover, because of its higher accuracy and load capacity, in comparison with serial mechanisms, it allows simulation of heavier tasks, such as climbing stairs, to be performed. This paper describes a new 3 Degree of freedom (DoF) spatial 2T1R (T: Translational DoF; R: Rotational DoF) parallel mechanism, for reproducing the force and motion of the tibial component of the knee prostheses in a wear test simulator. Kinematics and dynamics analysis of the mechanism indicated that it can satisfy the required DoFs, workspace and load capacity prescribed in the standard. Also, evaluation of the performance of the mechanism using the simMechanics toolbox of MATLAB revealed that it can reproduce the prescribed forces/torques with relatively high accuracy. However, the mechanism’s force outcomes were found to be affected by inaccuracies in mounting the prosthesis components, although less than the previous serial simulators. In comparison of the different possible architectures, a lateral leg angulation of 45 degrees provided the best efficacy, considering the size of actuators, the overall size of the mechanism and the accessibility of the test sample.

     

多指灵巧手主从控制系统的硬件设计

设计了一种超声电机驱动的多指灵巧手控制系统的硬件电路。给出灵巧手控制系统的硬件总体设计方案,并对灵巧手控制系统的译码电路、关节信息采集电路、超声电机启停和正反转电路、超声电机的调速电路等外围电路模块的硬件设计过程作了详细的阐述,并加以实现。     

一种新型压缩式垃圾桶的设计与制作

分析介绍了几种常见压缩垃圾桶的性能与结构特点,基于杠杆原理及四杆机构的综合,进行创新设计并制作了一款压缩式垃圾桶。该垃圾桶可以使垃圾在即将满桶时,及时实施垃圾的压缩,以便有效提高垃圾桶的储存能力,较大程度降低环卫工人的劳动强度和对环境的污染程度。     

举升机构优化设计

采用内点惩罚函数法对举升机构的关键件，气缸的两端支点的位置参数进行了优化设计。优化后的举升机构，不仅气缸行程最短，而且，整个机构的高度也比要求的大大降低，经实际使用效果很好。     

新型胀缩式堵头创新构思及设计

作者创新构思并设计了一种冷拔钢管用新型堵头－胀缩式堵头,总结提出了一种具有良好操作性的相似诱导移植创新法,适合遥于机械创新设计课题;给出了这种新型堵头的一种结构及其工作原理和主要参数选择计算。     

Design method and verification of a hybrid prosthetic mechanism with energy-damper clutchable device for transfemoral amputees

Transfemoral amputees (TAs) have difficulty in mobility during walking, such as restricted movement of lower extremity and body instability, yet few transfemoral prostheses have explored human-like multiple motion characteristics by simple structures to fit the kinesiology, biomechanics, and stability of human lower extremity. In this work, the configurations of transfemoral prosthetic mechanism are synthesized in terms of human lower-extremity kinesiology. A hybrid transfemoral prosthetic (HTP) mechanism with multigait functions is proposed to recover the gait functions of TAs. The kinematic and mechanical performances of the designed parallel mechanism are analyzed to verify their feasibility in transfemoral prosthetic mechanism. Inspired by motion–energy coupling relationship of the knee, a wearable energy-damper clutched device that can provide energy in knee stance flexion to facilitate the leg off from the ground and can impede the leg’s swing velocity for the next stance phase is proposed. Its co-operation with the springs in the prismatic pairs enables the prosthetic mechanism to have the energy recycling ability under the gait rhythm of the knee joint. Results demonstrate that the designed HTP mechanism can replace the motion functions of the knee and ankle to realize its multimode gait and effectively decrease the peak power of actuators from 94.74 to 137.05 W while maintaining a good mechanical adaptive stability.     

一种新型抗震课桌的设计与制作

分析介绍了国内外现有几种抗震类课桌的性能与结构特点,基于人机工程学基本原理,通过结构创新设计并制作了一种新型结构的抗震课桌.该课桌桌面采用木质面板、铝蜂窝板和不锈钢薄板三层复合结构,桌底设置金属十字框架,桌腿采用金属管件增强结构,并在可调高度的桌腿内部设置了易剪断上止动螺栓和可预紧弹性缓冲环节.而在桌脚则添加了可微调高...     

一种等离子切割机切割机构的设计

针对等离子切割在不锈钢板材下料方面的应用讨论,通过对目前下料方式的优缺点分析,阐述了等离子切割在该领域应用的重大意义,设计出了一种等离子切割机的整体结构方案,详细说明了切割工艺过程。同时,对机器切割机构部分进行了深入的探讨,通过对该机构的功能和运动分析、对各种实现方案的比较以及对关键部件的设计计算,提出了一种经济适用的结构方案。该切割机构结构简单,调整方便,能较好地满足切割生产要求。     

水下欠驱动机械手结构设计与仿真分析

面向水下机械手深海作业环境,研究设计了一种可用于水下环境的欠驱动机械手,机械手共有3个手指,每个手指有3个关节,是由连杆传动的欠驱动手指,欠驱动使手指抓取具有自适应性。分析了手指运动机理,研究设计了手指模块和整体结构,对手指进行了抓取静力学分析,在ADAMS软件中对机械手进行动力学仿真,验证了机械手结构的合理性与可行性。