Development of Parallel Architecture Spatial Compliant Manipulators

2001 ◽  
Author(s):  
S. L. Canfield ◽  
J. W. Beard ◽  
R. D. Parsons ◽  
N. Lobontiu ◽  
M. Paine ◽  
...  
Keyword(s):  
Low Cost ◽  
Parallel Architecture ◽  
Parallel Manipulators ◽  
Structure Design ◽  
Degree Of Freedom ◽  
Small Scale ◽  
Compliant Structure ◽  
Compliant Joints ◽  
Kinematic Models ◽  
And Control

Abstract This paper will present the development of two spatial compliant manipulators suitable for fabrication at a miniature or micro level and positioning on a micro or nano scale. These compliant manipulators are based on a parallel architecture that provides rotational motion about two axes and translations in one to three directions. These compliant devices form the first in a class of such compliant manipulators that combine the characteristics of parallel manipulators with the low cost, small-scale capabilities resulting from a compliant structure design. These manipulators will be developed as lumped-compliance devices, having architectures with relatively rigid links and compliant joints designed to render nearly equivalent kinematic motion. Appropriate kinematic models are developed for design and control. The work is then demonstrated through development of a 3 degree-of-freedom miniature compliant manipulator (MCM) and a five degree-of-freedom (dof) compliant manipulator for micro-pointing applications.

scholarly journals A Novel Approach of Parallel Retina-Like Computational Ghost Imaging

Sensors ◽  
2020 ◽  
Vol 20 (24) ◽  
pp. 7093
Author(s):  
Jie Cao ◽  
Dong Zhou ◽  
Fanghua Zhang ◽  
Huan Cui ◽  
Yingqiang Zhang ◽  
...  
Keyword(s):  
Wide Spectrum ◽  
Low Cost ◽  
Parallel Architecture ◽  
Structure Design ◽  
Ghost Imaging ◽  
Novel Approach ◽  
Time Correlations ◽  
Long Time ◽  
Sampling And Reconstruction ◽  
Similar Imaging

Computational ghost imaging (CGI), with the advantages of wide spectrum, low cost, and robustness to light scattering, has been widely used in many applications. The key issue is long time correlations for acceptable imaging quality. To overcome the issue, we propose parallel retina-like computational ghost imaging (PRGI) method to improve the performance of CGI. In the PRGI scheme, sampling and reconstruction are carried out by using the patterns which are divided into blocks from designed retina-like patterns. Then, the reconstructed image of each block is stitched into the entire image corresponding to the object. The simulations demonstrate that the proposed PRGI method can obtain a sharper image while greatly reducing the time cost than CGI based on compressive sensing (CSGI), parallel architecture (PGI), and retina-like structure (RGI), thereby improving the performance of CGI. The proposed method with reasonable structure design and variable selection may lead to improve performance for similar imaging methods and provide a novel technique for real-time imaging applications.

Improved Development Cycle of a Compliant Manipulator

2003 ◽  
Author(s):  
Stephen L. Canfield ◽  
Patrick V. Hull ◽  
James W. Beard
Keyword(s):  
Design Process ◽  
Design Methodology ◽  
Low Cost ◽  
Parallel Architecture ◽  
Degree Of Freedom ◽  
Modeling Tools ◽  
Multiple Features ◽  
Positioning Accuracy ◽  
Development Cycle ◽  
Three Degree Of Freedom

Application of the compliant design methodology to manipulators has held the promise of delivering manipulators with many significant advantages, including low cost, small size, low backlash and friction, and high positioning accuracy. This approach has been demonstrated in part by Canfield et. al., [1] to a class of three-degree-of-freedom manipulators based on a specific parallel architecture topology. In [1], the authors’ intent was to develop two compliant manipulators that exhibit several of the features associated with compliant devices. However, upon review of the manipulators resulting from this work it is observed that many of the benefits that were expected were lost at some point in the design process, resulting in manipulators that were large, expensive and suffered significantly from required assembly and inaccuracies in manufacture. This paper will revisit the problem addressed in [1], using the modeling tools demonstrated in that paper but will present several improved development measures that will result in manipulators that exhibit multiple features promised by compliant devices. The resulting manipulators will then be compared against the manipulators from [1] with a summary of the performance and characteristics of each given and evaluated.

A Comparative Study on Motion Characteristics of Three Two-Degree-of-Freedom Pointing Mechanisms

2016 ◽  
Vol 8 (2) ◽  
Author(s):  
Jingjun Yu ◽  
Kang Wu ◽  
Guanghua Zong ◽  
Xianwen Kong
Keyword(s):  
Parallel Manipulators ◽  
Degree Of Freedom ◽  
Pure Rolling ◽  
Motion Characteristics ◽  
And Control ◽  
Self Motion ◽  
Tracking Devices ◽  
Two Degree Of Freedom ◽  
Typical Difference ◽  
Composition Theorem

Two-degree-of-freedom (2DOF) pointing mechanisms have been widely used in areas such as stabilized platforms, tracking devices, etc. Besides the commonly used serial gimbal structures, another two types of parallel pointing mechanisms, i.e., spherical parallel manipulators (SPMs) and equal-diameter spherical pure rolling (ESPR) parallel manipulators, are increasingly concerned. Although all these pointing mechanisms have two rotational DOFs, they exhibit very different motion characteristics. A typical difference existing in these three pointing mechanisms can be found from their characteristics of self-motion, also called spinning motion by the authors. In this paper, the spinning motions of three pointing mechanisms are modeled and compared via the graphical approach combined with the vector composition theorem. According to our study, the spinning motion is essentially one component of the moving platform's real rotation. Furthermore, image distortions caused by three spinning motions are identified and distinguished when the pointing mechanisms are used as tracking devices. Conclusions would facilitate the design and control of the pointing devices and potentially improve the measuring accuracy for targets pointing and tracking.

An Efficient Inverse Acceleration Analysis of In-Parallel Manipulators

1996 ◽  
Author(s):  
José María Rico Martínez ◽  
Joseph Duffy
Keyword(s):  
Parallel Manipulator ◽  
Computing Time ◽  
Parallel Manipulators ◽  
Simple Expression ◽  
Degree Of Freedom ◽  
Simple Method ◽  
Dynamics And Control ◽  
Acceleration Analysis ◽  
Klein Form ◽  
And Control

Abstract A very simple novel expression for the accelerations of the six prismatic actuators, of the HPS connector chains, of a 6 degree of freedom in-parallel manipulator is derived. The expression is obtained by firstly computing the “accelerator” for a single HPS connector chain in terms of the joint velocities and accelerations. The accelerator is a function of the line coordinates of the joint axes and of a sequence of Lie products of the same line coordinates. A simple expression for the acceleration of the prismatic actuator is obtained by forming the Klein form, or reciprocal product, with the accelerator and the coordinates of the line of the connector chain. Since the Klein form is invariant, the resulting expression can be applied directly to the six HPS connector chains of an in-parallel manipulator. The authors believe that this simple method has important applications in the dynamics and control of these in-parallel manipulators where the computing time must be minimized to improve the behavior of parallel manipulators.

A Study on Design Manufacturing and Control of a Cable Controlled Motion Simulator With Visual Feedback Helmet and Their Application on a Simulator Simulation System

2010 ◽  
Author(s):  
Chun-Chi Peng ◽  
Ming-Guo Her ◽  
Ming-In Ho
Keyword(s):  
Low Cost ◽  
Degree Of Freedom ◽  
Infrared Transmission ◽  
Tactile Sense ◽  
Audio Feedback ◽  
Motion Simulator ◽  
Low Degree ◽  
Controlled Motion ◽  
And Control ◽  
High Degree

The purpose of this research is to simulate high degree of freedom motions with low degree of freedom motions. It breaks the rule of using high degree of freedom to simulate high degree of freedom motions. Besides, except for using expensive servo slider, the study uses cables to control the simulator to reach the purpose of simulating unlimited space with limited space of the simulator and it also reach the demands of low cost. In the research, the operator’s tactile sense in body is simulated; the “visual helmet” is also added. Compared with the traditional infrared transmission, it is faster and the changes of the produced environments are more immediate. This makes the operator feels more realistic in the variation of the virtual scenes. The combination of the cable controlled simulator and the visual helmet with the software of virtual reality games makes the operator obtain more actual simulating effects in visual, audio feedback and tactile, motion feedback. It makes operator feel as if s/he is in the real world.

scholarly journals Implementation of IoT With Image Processing in Greenhouse Monitoring System

2019 ◽  
Vol 8 (9) ◽  
pp. 509-514
Keyword(s):  
Low Cost ◽  
Infected Plant ◽  
Threshold Value ◽  
Plant Diseases ◽  
Raspberry Pi ◽  
Small Scale ◽  
Automation System ◽  
Plant Leaves ◽  
Prototype Development ◽  
And Control

Greenhouse automation system using Internet of Things (IoT) is a technical approach that benefits farmers by the automation and control of the greenhouse environment including plants health monitoring. Farmers' activities in the greenhouse are considered important in terms of producing strategic food for the population. In general, greenhouses are usually affected by the weather and plant diseases, as a result, their yield can be minimized and thus income is reduced. Through the analysis of the current situation of small-scale greenhouses, this paper proposes a low-cost solution for controlling, identifying, and classifying of infected plant leaves and automation of agricultural greenhouse. Design and prototype development of the proposed project has been done using Raspberry Pi, NODE MCU SP8266, different sensors and MATLAB. The programming language, MATLAB, is used to classify infected plant leaves, and sensors have been used to measure temperature and humidity of the greenhouse environment. In addition, controlling of actuators have been attained through solid state relays in order to turn the water drip system on or off upon reaching the predetermined threshold value. Finally, the greenhouse farmers interact with the proposed system via the cloud-based platform. This greenhouse automation system will benefit greenhouse farmers by enabling them to automatically monitor and control the greenhouse environment without their direct supervision.

Präzisions-Forstwirtschaft – was ist das? | Precision forestry – what's that?

2007 ◽  
Vol 158 (8) ◽  
pp. 235-242 ◽  
Author(s):  
Hans Rudolf Heinimann
Keyword(s):  
Business Processes ◽  
Spatial Scales ◽  
Supply Chain Coordination ◽  
Sensor Technology ◽  
Small Scale ◽  
Soil Physics ◽  
Coordination Problem ◽  
Precision Engineering ◽  
Precision Forestry ◽  
And Control

The term «precision forestry» was first introduced and discussed at a conference in 2001. The aims of this paper are to explore the scientific roots of the precision concept, define «precision forestry», and sketch the challenges that the implementation of this new concept may present to practitioners, educators, and researchers. The term «precision» does not mean accuracy on a small scale, but instead refers to the concurrent coordination and control of processes at spatial scales between 1 m and 100 km. Precision strives for an automatic control of processes. Precision land use differs from precision engineering by the requirements of gathering,storing and managing spatio-temporal variability of site and vegetation parameters. Practitioners will be facing the challenge of designing holistic, standardized business processes that are valid for whole networks of firms,and that follow available standards (e.g., SCOR, WoodX). There is a need to educate and train forestry professionals in the areas of business process re-engineering, computer supported management of business transactions,methods of remote sensing, sensor technology and control theory. Researchers will face the challenge of integrating plant physiology, soil physics and production sciences and solving the supply chain coordination problem (SCCP).

Identificación de polaridad de los devanados en un motor trifásico de 6 terminales

2019 ◽  
pp. 13-19
Author(s):  
José Luis Viramontes-Reyna ◽  
Josafat Moreno-Silva ◽  
José Guadalupe Montelongo-Sierra ◽  
Erasmo Velazquez-Leyva
Keyword(s):  
Low Cost ◽  
Voltage Reference ◽  
Three Phase ◽  
Voltage Phase ◽  
The Law ◽  
And Control

This document presents the results obtained from the application of the law of Lens to correctly identify the polarity of the windings in a three-phase motor with 6 exposed terminals, when the corresponding labeling is not in any situation; Prior to identifying the polarity, it should be considered to have the pairs of the three windings located. For the polarity, it is proposed to feed with a voltage of 12 Vrms to one of the windings, which are identified randomly as W1 and W2, where W1 is connected to the voltage phase of 12 Vrms of the signal and W2 to the voltage reference to 0V; by means of voltage induction and considering the law of Lens, the remaining 4 terminals can be identified and labeled as V1, V2, U1 and U2. For this process a microcontroller and control elements with low cost are used.

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