Low cost open loop vibrating reed mechanical spectrometer using pulse train excitation and capacitive current detection

Computer Numerical Control (CNC) is a technology that converts coded instructions and numerical data into sequential actions that describe the motion of machine axes or the behavior of an end effector. Nowadays, CNC technology has been introduced to different stages of production, such as rapid prototyping, machining and finishing processes, testing, packaging, and warehousing. The main objective of this chapter is to introduce a methodology for design and implementation of a simple and low-cost educational CNC prototype. The machine consists of three independent axes driven by stepper motors through an open-loop control system. Output pulses from the parallel port of Personal Computer (PC) are used to drive the stepper motors after processing by an interface card. A flexible, responsive, and real-time Visual C# program is developed to control the motion of the machine axes. The integrated design proposed in this chapter can provide engineers and students in academic institutions with a simple foundation to efficiently build a CNC machine based on the available resources. Moreover, the proposed prototype can be used for educational purposes, demonstrations, and future research.

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A Low-Cost Surge Current Detection Sensor with Predictive Lifetime Display Function for Maintenance of Surge Protective Devices

Sensors ◽

10.3390/s20082310 ◽

2020 ◽

Vol 20 (8) ◽

pp. 2310 ◽

Cited By ~ 2

Author(s):

Youngjun Lee ◽

Young Sam Lee

Keyword(s):

Liquid Crystal Display ◽

Low Cost ◽

Lightning Strike ◽

Protective Device ◽

Lcd Driver ◽

Display Function ◽

Duration Information ◽

Toroidal Coil ◽

Current Detection ◽

Surge Current

In this study, a low-cost surge current detection sensor (SCDS) that can measure high current surges using a low-current toroidal coil is proposed for maintenance of a surge protective device (SPD). The proposed SCDS is designed to display the predicted lifetime of the SPD based on the magnitude of surge current and number of surges. In addition, a method for measuring high surge current using a toroidal coil that can usually measure only low current is proposed. A lightning strike counter consists of a microcontroller with a low-power liquid crystal display (LCD) driver, 3 VDC lithium battery, and signal conditioning circuit that converts amplitude information of the surge current into duration information of a negative pulse to facilitate processing in the microcontroller. In this paper, we propose a software algorithm that can calculate the remaining lifetime of SPD based on the amplitude and number of surge currents. There is also an option to select the capacity of the surge protective device and the number of phase lines, allowing it to assess the predicted lifetime for various types of Class II SPDs. The proposed SCDS is measured as 7.2 μA from the battery power consumption test, and the service life is calculated to be 11.1 years. It meets the International Standard IEC62561-6 test conditions of the lightning strike counter and is expected to be useful in the maintenance of SPDs and lightning protection systems.

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A Low-Cost Differentially Driven Dual-Polarized Patch Antenna by Using Open-Loop Resonators

IEEE Transactions on Antennas and Propagation ◽

10.1109/tap.2019.2896491 ◽

2019 ◽

Vol 67 (4) ◽

pp. 2745-2750 ◽

Cited By ~ 10

Author(s):

Le-Hu Wen ◽

Steven Gao ◽

Qi Luo ◽

Qingling Yang ◽

Wei Hu ◽

...

Keyword(s):

Patch Antenna ◽

Low Cost ◽

Open Loop ◽

Dual Polarized

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Design of a Velocity Control System Using an Inlet Metered Pump

ASME/BATH 2017 Symposium on Fluid Power and Motion Control ◽

10.1115/fpmc2017-4310 ◽

2017 ◽

Cited By ~ 3

Author(s):

Hasan H. Ali ◽

Roger C. Fales ◽

Noah D. Manring

Keyword(s):

Fluid Flow ◽

Control System ◽

High Efficiency ◽

Flow Direction ◽

Low Cost ◽

Hydraulic Cylinder ◽

Fast Response ◽

Open Loop ◽

Velocity Control ◽

Pump System

This work introduces a new way to control hydraulic cylinder velocity using an inlet metering pump system to control the hydraulic flow entering the cylinder. The inlet metering system consists of a fixed displacement pump and an inlet metering valve that adjusts the hydraulic fluid flow entering the pump as required. The energy losses associated with flow metering in the system are reduced because the pressure drop across the inlet metering valve can be arbitrarily small. The fluid is supplied to the inlet metering valve at a fixed pressure using a charge pump. A velocity control system is designed using the inlet metering system as means to control the fluid flow to a hydraulic cylinder. In addition to the inlet metering system, the velocity control system designed in this work includes a four-way directional valve to set the fluid flow direction according to the desired direction of the hydraulic cylinder velocity. Open-loop and closed-loop proportional and proportional derivative (P and PD) controllers are designed. Designs with the goals of stability and performance of the system are studied so that a precise and smooth velocity control system for the hydraulic cylinder is achieved. In addition to potentially high efficiency of this system, there is potential for other benefits including low cost, fast response, and less complicated dynamics compared to other systems. The results presented in this work show that the inlet metering velocity control system can be designed so that the system is stable, there is zero overshoot and no oscillation.

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Development of a 3-DOF Tripedal Stick-Slip Microrobotic Mobile Platform for Unconstrained, Omnidirectional Sample Positioning

Volume 2: Control and Optimization of Connected and Automated Ground Vehicles; Dynamic Systems and Control Education; Dynamics and Control of Renewable Energy Systems; Energy Harvesting; Energy Systems; Estimation and Identification; Intelligent Transportation and Vehicles; Manufacturing; Mechatronics; Modeling and Control of IC Engines and Aftertreatment Systems; Modeling and Control of IC Engines and Powertrain Systems; Modeling and Management of Power Systems ◽

10.1115/dscc2018-9229 ◽

2018 ◽

Cited By ~ 1

Author(s):

Iman Adibnazari ◽

William S. Nagel ◽

Kam K. Leang

Keyword(s):

Visual Servoing ◽

Feedforward Control ◽

Low Cost ◽

Tracking Error ◽

Kinematic Model ◽

Open Loop ◽

Step Cycle ◽

Stick Slip ◽

Slip Step ◽

Forward Kinematic

This paper presents the development of a piezo-based three-degree-of-freedom (3-DOF), tripedal microrobotic platform that allows for unlimited travel with sub-micron precision over a planar surface. Compliant mechanical amplifiers are incorporated with each piezoelectric stack actuator to improve both the stroke and load-bearing capability of the platform. A forward kinematic model of the stage based on its tripedal leg architecture is derived for each stick-slip step cycle and inverted for feedforward control of the platform. A prototype is constructed using low-cost 3D-printing techniques. Experimental results demonstrate actuator stroke of 29.4 μm on average with a dominant resonance of approximately 860 Hz. Results demonstrate the stage tracks a 3 mm by 3 mm square trajectory in open loop. Feedback control through visual servoing is then simulated on a model that includes flexure dynamics, observed surface interactions, and camera sampling times, reducing the root-mean-square (RMS) tracking error by 90%. This control scheme is then implemented experimentally, resulting in 99% RMS position error reduction relative to when only feedforward control is used.

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A Compact Low-Cost Camera Module with Modified Magnetic Restoring Force

Journal of Mechanics ◽

10.1017/jmech.2016.121 ◽

2017 ◽

Vol 33 (4) ◽

pp. 475-482 ◽

Cited By ~ 4

Author(s):

C. S. Liu ◽

B. J. Tsai ◽

Y. H. Chang

Keyword(s):

Low Cost ◽

Open Loop ◽

Personal Digital Assistants ◽

Portable Devices ◽

Restoring Force ◽

Electronic Products ◽

Pattern Structure ◽

Camera Module ◽

Potential Applications ◽

Present Group

AbstractIn recent years, compact camera modules (CCMs) have been widely used in consumer electrical and electronic products. CCMs with low cost specially are necessary for portable devices. Therefore, the present group recently developed a miniaturized open-loop controlled camera module with low cost for cellphone applications, in which the Lorentz force is balanced by a magnetic restoring force. To enhance the performance of the camera module, this article reports a pattern structure to modify the linearity of the magnetic restoring force. We fabricated a CCM prototype with the dimensions of 8.5 mm × 8.5 mm × 5 mm and demonstrated the usefulness of the pattern structure with the CCM prototype. Its potential applications are foreseeable in portable devices, such as cellphones, web cameras, personal digital assistants and other commercial electronics.

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Research and Design of Control System for a 3-DOF Hybrid Robot

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.43.207 ◽

2010 ◽

Vol 43 ◽

pp. 207-210 ◽

Cited By ~ 1

Author(s):

Ju Li ◽

Hui Ping Shen ◽

Y.X. Jiang ◽

Jia Ming Deng ◽

Shan Shu Liu ◽

...

Keyword(s):

Control System ◽

Low Cost ◽

Hybrid Structure ◽

Open Loop ◽

The Body ◽

Step Motor ◽

Parallel Structure ◽

Loop Control ◽

Loop Control System ◽

Research And Design

This paper studied a novel 3-DOF hybrid robot, and invented a new hybrid structure which was composed of 2-DOF parallel structure and 1-DOF serial structure. The structure of this mechanism was simple, stiffness and positioning accuracy was high. The control system based on ARM micro-controller was a step motor open-loop control system, which features compact and low cost while the control accuracy can be guaranteed. In this paper, the body composition of the robot was described, and its inverse kinematics were derived and further simplified. Hardware and software of the motion control system was designed in detail and experimented through prototype.

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