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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

A Study on the Mechanism Design of the Planar Micro Compliant Pantograph

Chen, Wei-Fan 01 August 2005 (has links)
In the field of MEMS technology, all kinds of actuators are often regarded as the force source. However, some designs of actuators have good precision in position; the working distance to be driven is too short. Therefore, the actuator is often combined with a mechanism with displacement amplify function. The objective of this study is to synthesize the new pantograph mechanism using the concept of mechanism design according to the desirable motion and the requirement of the actuator. The cases of single degree-of-freedom and two degree-of-freedom are assumed simultaneously for the output of the basic design constraints so as to generate new pantograph mechanisms from the catalogue of kinematic chains. The suitable pantographs are then found out with the features such as: (1) single level plane using comb driver, (2) using compliant mechanisms as joints, and (3) suitable for MUMPs process. These constraints of design are considered as the procedures of process design, compliant mechanisms transformation, compliant joints design, actuator configurations design, FEM dynamic analysis and joint modifications. Finally, prototypes are evaluated and transform into planar micro compliant pantographs. Moreover, a test and a discussion of the displacement error are done under the consideration of the designed mechanism actuating using FEM analysis. The percentage of displacement error of planar micro compliant pantograph is defined, and the equation for estimating the percentage of displacement error is proposed so as to modify the motion error for controlling.
152

A Study on the Design of Auxiliary Walking Mechanisms for Lower Limb Disablement

Chen, Yu-ting 08 September 2006 (has links)
Orthoses and auxiliaries are important to the people with lower limb disabled in their daily lives. The purpose of this study is to survey and discuss the existing walking auxiliary mechanism for the lower limb disabled people, and to design a new walking auxiliary mechanism to improve their walking gesture. In order to develop a new auxiliary mechanism for the people with lower limb disabled, commercial orthoses and patents are colleted, analyzed, classified, and compared to each others. Several interviews with a lower limb disablement are arranged and understand what they need. After integrating all the collected information as the design input, theories of mechanism structure synthesis, dimension synthesis, mechanism analysis are utilized to develop a mechanism design of auxiliary for lower limb disabled people to walk, to go up and down the stair. The Pro-Engineering, a CAD software, is used for solid modeling and the Visual Nastran, a CAE software, is applied for motion simulation. The results of computer simulations of walking and climbing up stairs are compared to that of video taken from the interviewed people.
153

Design and control of a robotic manipulator with an active pneumatic balancing system

李錦發, Lee, Kam-fat, Jonathan. January 1992 (has links)
published_or_final_version / Mechanical Engineering / Master / Master of Philosophy
154

Inverse kinematics of robot manipulators in the presence of singularities and redundancies

Anderson, Karen, 1959- January 1987 (has links)
No description available.
155

On mappings of complex inverse kinematics solutions

Pohl, Eric David 08 1900 (has links)
No description available.
156

Optimal Design Methods for Increasing Power Performance of Multiactuator Robotic Limbs

January 2017 (has links)
abstract: In order for assistive mobile robots to operate in the same environment as humans, they must be able to navigate the same obstacles as humans do. Many elements are required to do this: a powerful controller which can understand the obstacle, and power-dense actuators which will be able to achieve the necessary limb accelerations and output energies. Rapid growth in information technology has made complex controllers, and the devices which run them considerably light and cheap. The energy density of batteries, motors, and engines has not grown nearly as fast. This is problematic because biological systems are more agile, and more efficient than robotic systems. This dissertation introduces design methods which may be used optimize a multiactuator robotic limb's natural dynamics in an effort to reduce energy waste. These energy savings decrease the robot's cost of transport, and the weight of the required fuel storage system. To achieve this, an optimal design method, which allows the specialization of robot geometry, is introduced. In addition to optimal geometry design, a gearing optimization is presented which selects a gear ratio which minimizes the electrical power at the motor while considering the constraints of the motor. Furthermore, an efficient algorithm for the optimization of parallel stiffness elements in the robot is introduced. In addition to the optimal design tools introduced, the KiTy SP robotic limb structure is also presented. Which is a novel hybrid parallel-serial actuation method. This novel leg structure has many desirable attributes such as: three dimensional end-effector positioning, low mobile mass, compact form-factor, and a large workspace. We also show that the KiTy SP structure outperforms the classical, biologically-inspired serial limb structure. / Dissertation/Thesis / Doctoral Dissertation Mechanical Engineering 2017
157

Omnidirectional Mobile Mechanisms and Integrated Motor Mechanisms for Wheeled Locomotion Devices / 車輪式移動装置用の全方向移動機構と統合型モータ機構の研究

Terakawa, Tatsuro 25 March 2019 (has links)
付記する学位プログラム名: デザイン学大学院連携プログラム / 京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21755号 / 工博第4572号 / 新制||工||1713(附属図書館) / 京都大学大学院工学研究科機械理工学専攻 / (主査)教授 小森 雅晴, 教授 松野 文俊, 教授 松原 厚 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
158

The Application of Origami to the Design of Lamina Emergent Mechanisms (LEMs) with Extensions to Collapsible, Compliant and Flat-Folding Mechanisms

Greenberg, Holly 30 April 2012 (has links) (PDF)
Lamina emergent mechanisms (LEMs) are a subset of compliant mechanisms which are fabricated from planar materials; use compliance, or flexibility of the material, to transfer energy; and have motion that emerges out of the fabrication plane. LEMs provide potential design advantages by reducing the number of parts, reducing cost, reducing weight, improving recyclability, increasing precision, and eliminating assembly, to name a few. However, there are inherent design and modeling challenges including complexities in large, non-linear deflections, singularities that exist when leaving the planar state, and the coupling of material properties and geometry in predicting mechanism behavior. This thesis examines the planar and spherical LEMs and their relation to origami. Origami, the art of paper folding, is used to better understand spherical LEMs and flat-folding mechanisms in general. All single-layer planar four-bar LEMs are given with their respective layouts. These are all change-point pinned mechanisms (i.e. no slider cranks). Graph representations are used to show the similarities between action origami and mechanisms. Origami principles of flat-folding are shown to be analogous to principles of mechanisms including rules for assembly and motion.
159

Rapid Conceptual Design and Analysis of Planar and SpatialCompliant Mechanisms

Turkkan, Omer Anil 24 May 2018 (has links)
No description available.
160

Inverse kinematics of robot manipulators in the presence of singularities and redundancies

Anderson, Karen January 1987 (has links)
No description available.

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