scholarly journals Impedance Control Self-Calibration of a Collaborative Robot Using Kinematic Coupling

Robotics ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 33 ◽  
Author(s):  
Nicholas A. Nadeau ◽  
Ilian A. Bonev ◽  
Ahmed Joubair
Keyword(s):  
Impedance Control ◽  
Low Cost ◽  
Data Communication ◽  
Maximum Error ◽  
Calibration Procedure ◽  
Laser Tracker ◽  
Communication Architecture ◽  
Control Approach ◽  
Kinematic Coupling ◽  
Set Up

This paper presents a closed-loop calibration approach using impedance control. The process is managed by a data communication architecture based on open-source tools and designed for adaptability. The calibration procedure uses precision spheres and a kinematic coupling standard machine tool components, which are suitable for harsh industrial environments. As such, the required equipment is low cost (approximately group-separator = , 2000 [$]USD), robust, and is quick to set up, especially when compared to traditional calibration devices. As demonstrated through an experimental study and validated with a laser tracker, the absolute accuracy of the KUKA LBR iiwa robot was improved to a maximum error of 0 . 990 , representing a 58.4% improvement when compared to the nominal model. Further testing showed that a traditional calibration using a laser tracker only improved the maximum error by 58 μ m over the impedance control approach.

scholarly journals Non-intrusive techniques to measure roll waves level evolving in a flume

2018 ◽  
Vol 40 ◽  
pp. 05049
Author(s):  
Geraldo de Freitas Maciel ◽  
Evandro Fernandes da Cunha ◽  
Yuri Taglieri Sao ◽  
André Luis Toniati ◽  
Guilherme Henrique Fiorot ◽  
...  
Keyword(s):  
Low Cost ◽  
Ultrasonic Transducer ◽  
Calibration Procedure ◽  
Test Fluid ◽  
Level Measurement ◽  
Roll Waves ◽  
Experimental Apparatus ◽  
Set Up ◽  
Favorable Conditions ◽  
And Control

An open-channel experimental set-up is presented in this paper as a tool for examining the presence of instabilities on free-surfaces flows of non-Newtonian fluid. When these flows occur in favorable conditions of inclination, discharge and rheological properties, the propagation of instabilities can evolve into a specific type of wave, known as roll waves. The experimental apparatus developed allows study of stabilized roll waves in many scenarios for non-Newtonian rheology fluids, thereby constituting a highly useful tool for the understanding and control of roll waves. The test fluid used in the experiments was carbopol gel which is rheometrically representative of the muddy material from natural disasters, such as mudflows. Two non-intrusive level measurement systems are proposed (ultrasonic transducer and laser-based absorption technique), and the efficiency of each technique is presented and discussed. Both methods presented relatively low-cost implementation, and calibration procedure assured the quality of the results. The results from the experimental set-up were in agreement in shape and amplitude.

Development of a Capacitor Probe to Detect Subsurface Deterioration in Concrete

1997 ◽  
Vol 503 ◽  
Author(s):  
B. K. Diefenderfer ◽  
I. L. Al-Qadi ◽  
J. J. Yoho ◽  
S. M. Riad ◽  
A. Loulizi
Keyword(s):  
Dielectric Constant ◽  
Portland Cement ◽  
Electromagnetic Waves ◽  
Low Cost ◽  
Complex Dielectric Constant ◽  
Life Cycle Costs ◽  
Parallel Plates ◽  
Portland Cement Concrete ◽  
Cement Concrete ◽  
Set Up

ABSTRACTPortland cement concrete (PCC) structures deteriorate with age and need to be maintained or replaced. Early detection of deterioration in PCC (e.g., alkali-silica reaction, freeze/thaw damage, or chloride presence) can lead to significant reductions in maintenance costs. However, it is often too late to perform low-cost preventative maintenance by the time deterioration becomes evident. By developing techniques that would enable civil engineers to evaluate PCC structures and detect deterioration at early stages (without causing further damage), optimization of life-cycle costs of the constructed facility and minimization of disturbance to the facility users can be achieved.Nondestructive evaluation (NDE) methods are potentially one of the most useful techniques ever developed for assessing constructed facilities. They are noninvasive and can be performed rapidly. Portland cement concrete can be nondestructively evaluated by electrically characterizing its complex dielectric constant. The real part of the dielectric constant depicts the velocity of electromagnetic waves in PCC. The imaginary part, termed the “loss factor,” describes the conductivity of PCC and the attenuation of electromagnetic waves.Dielectric properties of PCC have been investigated in a laboratory setting using a parallel plate capacitor operating in the frequency range of 0.1 to 40.1MIHz. This capacitor set-up consists of two horizontal-parallel plates with an adjustable separation for insertion of a dielectric specimen (PCC). While useful in research, this approach is not practical for field implementation. A new capacitor probe has been developed which consists of two plates, located within the same horizontal plane, for placement upon the specimen to be tested. Preliminary results show that this technique is feasible and results are promising; further testing and evaluation is currently underway.

Fault Localization of Power-Ground Short via Signal Injection and Oscilloscope Technique

2010 ◽  
Author(s):  
Binh Nguyen
Keyword(s):  
Low Cost ◽  
Short Circuit ◽  
Fault Localization ◽  
Fault Isolation ◽  
Test Apparatus ◽  
Good Working ◽  
Signal Injection ◽  
Set Up ◽  
Non Destructive ◽  
Short Circuit Condition

Abstract For those attempting fault isolation on computer motherboard power-ground short issues, the optimal technique should utilize existing test equipment available in the debug facility, requiring no specialty equipment as well as needing a minimum of training to use effectively. The test apparatus should be both easy to set up and easy to use. This article describes the signal injection and oscilloscope technique which meets the above requirements. The signal injection and oscilloscope technique is based on the application of Ohm's law in a short-circuit condition. Two experiments were conducted to prove the effectiveness of these techniques. Both experiments simulate a short-circuit condition on the VCC3 power rail of a good working PC motherboard and then apply the signal injection and oscilloscope technique to localize the short. The technique described is a simple, low cost and non-destructive method that helps to find the location of the power-ground short quickly and effectively.

scholarly journals A 40 Mb/s VLC System Reusing an Existing Large LED Panel in an Indoor Office Environment

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1697
Author(s):  
Xicong Li ◽  
Zabih Ghassemlooy ◽  
Stanislav Zvánovec ◽  
Paul Anthony Haigh
Keyword(s):  
Modulation Depth ◽  
Light Emitting Diode ◽  
Low Cost ◽  
Data Communication ◽  
Experimental System ◽  
Digital Signal ◽  
Visible Light Communication ◽  
Cost Driver ◽  
Limiting Factors ◽  
Light Sources

With advances in solid-state lighting, visible light communication (VLC) has emerged as a promising technology to enhance existing light-emitting diode (LED)-based lighting infrastructure by adding data communication capabilities to the illumination functionality. The last decade has witnessed the evolution of the VLC concept through global standardisation and product launches. Deploying VLC systems typically requires replacing existing light sources with new luminaires that are equipped with data communication functionality. To save the investment, it is clearly desirable to make the most of the existing illumination systems. This paper investigates the feasibility of adding data communication functionality to the existing lighting infrastructure. We do this by designing an experimental system in an indoor environment based on an off-the-shelf LED panel typically used in office environments, with the dimensions of 60 × 60 cm2. With minor modifications, the VLC function is implemented, and all of the modules of the LED panel are fully reused. A data rate of 40 Mb/s is supported at a distance of up to 2 m while using the multi-band carrierless amplitude and phase (CAP) modulation. Two main limiting factors for achieving higher data rates are observed. The first factor is the limited bandwidth of the LED string inside the panel. The second is the flicker due to the residual ripple of the bias current that is generated by the panel’s driver. Flicker is introduced by the low-cost driver, which provides bias currents that fluctuate in the low frequency range (less than several kilohertz). This significantly reduces the transmitter’s modulation depth. Concurrently, the driver can also introduce an effect that is similar to baseline wander at the receiver if the flicker is not completely filtered out. We also proposed a solution based on digital signal processing (DSP) to mitigate the flicker issue at the receiver side and its effectiveness has been confirmed.

Optimum Design for the Frame of Open Type Abrasive Flow Polish Machine

2012 ◽  
Vol 497 ◽  
pp. 89-93
Author(s):  
Liang Liang Yuan ◽  
Ke Hua Zhang ◽  
Li Min
Keyword(s):  
Finite Element ◽  
Natural Frequency ◽  
Finite Element Methods ◽  
Optimization Design ◽  
Low Cost ◽  
Three Dimensional ◽  
Force Model ◽  
Optimization Analysis ◽  
Open Type ◽  
Set Up

In order to process heterotype hole of workpiece precisely, an open abrasive flow polish machine is designed, and the optimization design of machine frame is done for low cost. Firstly, basing on the parameters designed with traditional ways, three-dimensional force model is set up with the soft of SolidWorks. Secondly, the statics and modal analysis for machine body have been done in Finite element methods (FEM), and then the optimization analysis of machine frame has been done. At last, the model of rebuild machine frame has been built. Result shows that the deformation angle value of machine frame increased from 0.72′ to 1.001′, the natural frequency of the machine decreased from 75.549 Hz to 62.262 Hz, the weight of machine decreased by 74.178 Kg after optimization. It meets the strength, stiffness and angel stiffness requirement of machine, reduces the weight and cost of machine.

scholarly journals Sensor Networks for Structures Health Monitoring: Placement, Implementations, and Challenges—A Review

Vibration ◽  
2021 ◽  
Vol 4 (3) ◽  
pp. 551-584
Author(s):  
Samir Mustapha ◽  
Ye Lu ◽  
Ching-Tai Ng ◽  
Pawel Malinowski
Keyword(s):  
Sensor Networks ◽  
Health Monitoring ◽  
Data Transmission ◽  
System Integration ◽  
Structural Integrity ◽  
Low Cost ◽  
Data Communication ◽  
Total Cost ◽  
Design And Optimization ◽  
Successful Case

The development of structural health monitoring (SHM) systems and their integration in actual structures has become a necessity as it can provide a robust and low-cost solution for monitoring the structural integrity of and the ability to predict the remaining life of structures. In this review, we aim at focusing on one of the important issues of SHM, the design, and implementation of sensor networks. Location and number of sensors, in any SHM system, are of high importance as they impact the system integration, system performance, and accuracy of assessment, as well as the total cost. Hence we are interested in shedding the light on the sensor networks as an essential component of SHM systems. The review discusses several important parameters including design and optimization of sensor networks, development of academic and commercial solutions, powering of sensors, data communication, data transmission, and analytics. Finally, we presented some successful case studies including the challenges and limitations associated with the sensor networks.

scholarly journals Innovative passive reinforcements for the gradual stabilization of a landslide according with the observational method

Landslides ◽  
2021 ◽  
Author(s):  
Lorenzo Brezzi ◽  
Alberto Bisson ◽  
Davide Pasa ◽  
Simonetta Cola
Keyword(s):  
Monitoring System ◽  
Low Cost ◽  
Economic Losses ◽  
Fe Model ◽  
Site Conditions ◽  
Observational Method ◽  
Rainy Period ◽  
Sustainable Solutions ◽  
Before And After ◽  
Set Up

AbstractA large number of landslides occur in North-Eastern Italy during every rainy period due to the particular hydrogeological conditions of this area. Even if there are no casualties, the economic losses are often significant, and municipalities frequently do not have sufficient financial resources to repair the damage and stabilize all the unstable slopes. In this regard, the research for more economically sustainable solutions is a crucial challenge. Floating composite anchors are an innovative and low-cost technique set up for slope stabilization: it consists in the use of passive sub-horizontal reinforcements, obtained by coupling a traditional self-drilling bar with some tendons cemented inside it. This work concerns the application of this technique according to the observational method described within the Italian and European technical codes and mainly recommended for the design of geotechnical works, especially when performed in highly uncertain site conditions. The observational method prescribes designing an intervention and, at the same time, using a monitoring system in order to correct and adapt the project during realization of the works on the basis of new data acquired while on site. The case study is the landslide of Cischele, a medium landslide which occurred in 2010 after an exceptional heavy rainy period. In 2015, some floating composite anchors were installed to slow down the movement, even if, due to a limited budget, they were not enough to ensure the complete stabilization of the slope. Thanks to a monitoring system installed in the meantime, it is now possible to have a comparison between the site conditions before and after the intervention. This allows the evaluation of benefits achieved with the reinforcements and, at the same time, the assessment of additional improvements. Two stabilization scenarios are studied through an FE model: the first includes the stabilization system built in 2015, while the second evaluates a new solution proposed to further increase the slope stability.

HAMSTER - Healthy, mobility and security-based data communication architecture for Unmanned Aircraft Systems

2014 ◽  
Author(s):  
Daniel Fernando Pigatto ◽  
Leandro Goncalves ◽  
Alex Sandro Roschildt Pinto ◽  
Guilherme Freire Roberto ◽  
Julio Fernando Rodrigues Filho ◽  
...  
Keyword(s):  
Data Communication ◽  
Unmanned Aircraft ◽  
Unmanned Aircraft Systems ◽  
Communication Architecture ◽  
Aircraft Systems

Research on the Character of a Synchronous Control System with Wireless Data Communication

2010 ◽  
Vol 455 ◽  
pp. 206-210
Author(s):  
Jun Li Liu ◽  
Yan Yan Yan ◽  
G.Q. He
Keyword(s):  
Control System ◽  
Time Delay ◽  
Data Transmission ◽  
Data Communication ◽  
Control Model ◽  
Data Loss ◽  
Wireless Data ◽  
Synchronous Control ◽  
Wireless Data Transmission ◽  
Set Up

It discusses the reasons of the data transmission time delay and packets loss based on the theory of net data transmission. Aimed to the question of the time delay of data transmission and packets loss, the control system models are set up to analyze their influence to the performance of the control system. Based on the synchronous control model analysis with wireless data transmission, a method to control the system is reached with the state prediction when the communication error or data loss appears. It can control constantly when communication errors appear, and also it can get the most error period by numerical analysis.

scholarly journals Specialist pneumonia intervention nurse service improves pneumonia care and outcome

2021 ◽  
Vol 8 (1) ◽  
pp. e000863
Author(s):  
Robert C Free ◽  
Matthew Richardson ◽  
Camilla Pillay ◽  
Kayleigh Hawkes ◽  
Julie Skeemer ◽  
...  
Keyword(s):  
Quality Improvement ◽  
National Health Service ◽  
Low Cost ◽  
Community Acquired Pneumonia ◽  
National Audit ◽  
Mortality Benefit ◽  
Model Of Care ◽  
Spin Period ◽  
National Health Service Trust ◽  
Set Up

BackgroundA specialist pneumonia intervention nursing (SPIN) service was set up across a single National Health Service Trust in an effort to improve clinical outcomes. A quality improvement evaluation was performed to assess the outcomes associated with implementing the service before (2011–2013) and after (2014–2016) service implementation.ResultsThe SPIN service reviewed 38% of community-acquired pneumonia (CAP) admissions in 2014–2016. 82% of these admissions received antibiotic treatment in <4 hours (68.5% in the national audit). Compared with the pre-SPIN period, there was a significant reduction in both 30-day (OR=0.77 (0.70–0.85), p<0.0001) and in-hospital (OR=0.66 (0.60–0.73), p<0.0001) mortality after service implementation, with a review by the service showing the largest independent 30-day mortality benefit (HR=0.60 (0.53–0.67), p<0.0001). There was no change in length of stay (median 6 days).ConclusionImplementation of a SPIN service improved adherence to BTS guidelines and achieved significant reductions in CAP-associated mortality. This enhanced model of care is low cost, highly effective and readily adoptable in secondary care.

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