An Application of Relay Feedback to Mass Measurement Under Weightless Conditions

2007 ◽  
Author(s):  
Takeshi Mizuno ◽  
Minoru Takeuchi ◽  
Yuji Ishino ◽  
Masaya Takasaki
Keyword(s):  
Measurement Errors ◽  
Mass Measurement ◽  
Dead Zone ◽  
Voice Coil Motor ◽  
Feedback System ◽  
Time Interval ◽  
Force Output ◽  
Relay Feedback ◽  
Relay Element ◽  
Measurement Object

Relay feedback was applied to measuring mass even under weightless conditions. A measurement object is driven by a force-output actuator. The motion of the object is controlled by a relay feedback system. The used relay element has dead zone and switches force acting on the object in relation to the position of the measurement object. The mass of the object is determined from the time interval measurement of the on-state and off-state periods. An apparatus was developed for experimental study. It uses a voice coil motor as an actuator, and a pair of photo interrupters for detecting the switching positions. The effects of system parameters on measurement accuracy were studied experimentally. Under the tuned conditions, the measurement errors were within 0.2[%]. Measurement on a base moving freely was also carried out.

scholarly journals Time interval measurement module implemented in SoC FPGA device

2016 ◽  
Vol 62 (3) ◽  
pp. 237-246 ◽  
Author(s):  
Grzegorz Grzęda ◽  
Ryszard Szplet
Keyword(s):  
Mass Measurement ◽  
Measurement Data ◽  
Measurement Instrument ◽  
General Concept ◽  
Time Interval ◽  
Processing Unit ◽  
Test Results ◽  
Interval Measurement ◽  
Time Interval Measurement ◽  
On Chip

Abstract We presents the design and test results of a picosecond-precision time interval measurement module, integrated as a System-on-Chip in an FPGA device. Implementing a complete measurement instrument of a high precision in one chip with the processing unit gives an opportunity to cut down the size of the final product and to lower its cost. Such approach challenges the constructor with several design issues, like reduction of voltage noise, propagating through power lines common for the instrument and processing unit, or establishing buses efficient enough to transport mass measurement data. The general concept of the system, design hierarchy, detailed hardware and software solutions are presented in this article. Also, system test results are depicted with comparison to traditional ways of building a measurement instrument.

scholarly journals High-resolution fiber-coupled interferometric point sensor for micro- and nano-metrology

2015 ◽  
Vol 82 (7-8) ◽  
Author(s):  
Markus Schake ◽  
Markus Schulz ◽  
Peter Lehmann
Keyword(s):  
High Resolution ◽  
Measurement Errors ◽  
Surface Profile ◽  
Optical Measurements ◽  
High Demand ◽  
Force Microscopy ◽  
Atomic Force ◽  
Measurement Object ◽  
Contact Free

AbstractThe determination of surface roughness is a common challenge in industrial quality assurance. Because tactile techniques like the stylus method or atomic force microscopy run the risk of damaging the measurement object there is a high demand for contact-free optical measurements. In this contribution we demonstrate the feasibility of a high resolution fiber-coupled interferometric point sensor with periodical path length modulation to determine the surface profile of rough surfaces. Measurements on two specimens characterized by different roughness parameters are presented and corrections for common measurement errors, due to phase ambiguity are discussed.

Possible existence of a long-loop feedback system between FSH and inhibin in female rats

1981 ◽  
Vol 240 (5) ◽  
pp. E544-E549 ◽  
Author(s):  
L. V. DePaolo ◽  
L. D. Anderson ◽  
A. N. Hirshfield
Keyword(s):  
Follicle Stimulating Hormone ◽  
Feedback System ◽  
Female Rats ◽  
Time Interval ◽  
Ether Anesthesia ◽  
Peripheral Plasma ◽  
Loop Feedback ◽  
Ovarian Inhibin ◽  
Venous Plasma

Experiments were designed in which peripheral plasma inhibin levels were presumably altered in an attempt to investigate an interdependency between pituitary follicle-stimulating hormone (FSH) and ovarian inhibin secretion. In the first study, unilateral ovariectomy (ULO) was performed on 4-day cycling female rats under ether anesthesia at 0800 h on diestrous day 1 (D1). Inhibin-like activity [FSH-inhibiting activity(FSH-IA)] in untreated ovarian venous plasma (OVP) collected from the remaining ovary was assessed by an in vitro pituitary bioassay system. Both plasma FSH levels and FSH-IA significantly increased between 4 and 12 h after ULO. Thereafter, plasma FSH declined between 12 and 32 h after ULO, whereas FSH-IA remained elevated during this same time interval. Compared to sham-operated rats, plasma FSH was significantly elevated 4, 12, and 24 h after ULO, whereas FSH-IA was statistically higher only at 32 h after ULO. In a second experiment, rats were injected with charcoal-treated porcine follicular fluid (PFF) on proestrus and estrus. Control rats received saline. The data indicate that increased plasma FSH levels on D1 in PFF-treated rats (FSH rebound) may be a consequence of reduced endogenous inhibin secretion on estrus. As well, return of FSH to control levels on D2 in PFF-treated rats may have resulted from an FSH-associated increase in FSH-IA on D1 and D2.

scholarly journals Mass Measurement System Using Relay Feedback with Hysteresis

2008 ◽  
Vol 2 (1) ◽  
pp. 188-196 ◽  
Author(s):  
Takeshi MIZUNO ◽  
Takahiro ADACHI ◽  
Masaya TAKASAKI ◽  
Yuji ISHINO
Keyword(s):  
Measurement System ◽  
Mass Measurement ◽  
Relay Feedback

scholarly journals SELF-OSCILLATIONS AND SLIDING IN RELAY FEEDBACK SYSTEMS: SYMMETRY AND BIFURCATIONS

2001 ◽  
Vol 11 (04) ◽  
pp. 1121-1140 ◽  
Author(s):  
MARIO DI BERNARDO ◽  
KARL HENRIK JOHANSSON ◽  
FRANCESCO VASCA
Keyword(s):  
Dynamical Systems ◽  
Periodic Solutions ◽  
Bifurcation Analysis ◽  
Feedback System ◽  
Feedback Systems ◽  
Relay Feedback ◽  
Linear Dynamical Systems ◽  
Local Bifurcations

This paper is concerned with the bifurcation analysis of linear dynamical systems with relay feedback. The emphasis is on the bifurcations of the system periodic solutions and their symmetry. It is shown that, despite what has been conjectured in the literature, a symmetric and unforced relay feedback system can exhibit asymmetric periodic solutions. Moreover, the occurrence of periodic solutions characterized by one or more sections lying within the system discontinuity set is outlined. The mechanisms underlying their formation are carefully studied and shown to be due to an interesting, novel class of local bifurcations.

Assessment of the measuring errors in tipping rain gauge located on a small mountain basin

2020 ◽  
Author(s):  
Leonor Rodriguez-Sinobas ◽  
Daniel Alberto Segovia-Cardozo ◽  
Sergio Zubelzu ◽  
Enrique Estefania ◽  
Andrés Díez-Herrero
Keyword(s):  
Measurement Errors ◽  
Rain Gauge ◽  
Sampling Procedure ◽  
Irrigation Scheduling ◽  
Time Interval ◽  
Manufacturing Cost ◽  
Calibration Data ◽  
Rain Gauges ◽  
Precipitation Measurement ◽  
High Precipitation

<p>Precipitation measurement has always been of human interest. Its estimation can guide the decisions concerning flooding prevention and irrigation scheduling in semi-arid regions.</p><p>Nowadays, manufactures offer several types of rain gauges. Among them, the tipping-bucket rain gauges (TBRs) is the most frequently used worldwide to collect rainfall data. It structure is simple and the manufacturing cost is reasonable. Also, the operating mechanical mechanism saves energy and can be easily automated. Its manufacture began in the seventeenth century although the recent models have improved their original characteristics.</p><p>Likewise, these gauges have some disadvantages such us: measurement errors, that can be significant during heavy rainfall or light drizzle; losses from evaporation and wind effects; time of onset; sampling procedure and rain residue in the bucket. Therefore, calibration is often needed.</p><p>This study assesses the data from a set of 12 TBRs spread in the small mountain basin “Venero Claro”, Avila (Spain). This is highly monitored due to its capacity to generate torrential flows and flash floods.  The data comprised a time interval of 14 years; the oldest TBRs were installed in 2006. The objective was quantified the errors, especially those caused by high precipitation intensities, which are common in the area. Thus, calibration curves for data analysis were estimated by a dynamic laboratory calibration for two different TBRs’ models.</p><p>The results from the calibration data have been statistically analysed in order to determine the errors and their significance along time and topography. A significant underestimation was observed in TBRs, especially in those located at higher areas.</p>

scholarly journals Mass Measurement Using a System Containing an On-Off Relay with Dead Zone

2005 ◽  
Vol 41 (1) ◽  
pp. 25-30 ◽  
Author(s):  
Takeshi MIZUNO ◽  
Minoru TAKEUCHI ◽  
Masaya TAKASAKI ◽  
Yuji ISHINO
Keyword(s):  
Mass Measurement ◽  
Dead Zone
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