Analysis of a High-Speed Solenoid-Actuated Mechanism

1968 ◽  
Vol 90 (3) ◽  
pp. 441-448 ◽  
Author(s):  
R. L. Wirth
Keyword(s):  
Mechanical System ◽  
High Speed ◽  
Lumped Parameter Model ◽  
Electromagnetic System ◽  
Motion Equations ◽  
Lumped Parameter ◽  
Intermittent Contact ◽  
Impressed Current ◽  
Systematic Solution ◽  
The Relationship

The mechanism which is considered in this paper is a high-speed, solenoid-driven, impact printing mechanism. The purpose of the analysis is to construct a mathematical model of the mechanism from which the dynamics of the mechanism can be studied during a complete printing cycle. The basic approach taken is to construct a lumped parameter model of the mechanical system. Motion equations are written which are solved simultaneously with equations governing the electromagnetic system. Elements of the mechanical system which are described include viscoelastic buffers between impacting parts. Dead space or intermittent contact between parts is another aspect of the problem which is defined. The relationship between core flux and impressed current is established through an experimentally measured magnetization curve. Equations governing both the rise and fall of the magnetic flux are developed since a complete cycle of operation is under study. The resulting set of equations is nonlinear in nature and impractical to solve by hand. However, a systematic solution to the equations is readily obtained by numerical integration on a digital computer.

Soft Switching in Switched Inertance Hydraulic Circuits

2016 ◽  
Author(s):  
Alexander C. Yudell ◽  
James D. Van de Ven
Keyword(s):  
High Speed ◽  
Soft Switching ◽  
Power Delivery ◽  
Lumped Parameter Model ◽  
Energy Losses ◽  
Hydraulic Systems ◽  
Zero Voltage Switching ◽  
Lumped Parameter ◽  
Capacitive Element ◽  
Zero Voltage

Switched Inertance Hydraulic Systems (SIHS) use inductive, capacitive, and switching elements to boost or buck a pressure from a source to a load in an ideally lossless manner. Real SIHS circuits suffer a variety of energy losses, with throttling of flow during transitions of the high-speed valve resulting in 44% of overall losses. These throttling energy losses can be mitigated by applying the analog of zero-voltage-switching, a soft switching strategy, adopted from power electronics. In the soft switching circuit, the flow that would otherwise be throttled across the transitioning valve is stored in a capacitive element and bypassed through check valves in parallel with the switching valves. To evaluate the effectiveness of soft switching in a boost converter SIHS, a lumped parameter model was constructed. The model demonstrates that soft switching can improve the efficiency of the circuit up to 42% and extend the power delivery capabilities of the circuit by 76%.

scholarly journals Evaluation of a Combustion-Based Mesoscale Thermal Actuator in Open and Closed Operating Cycles

Actuators ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 73
Author(s):  
Sindhu Preetham Burugupally
Keyword(s):  
Heat Input ◽  
High Speed ◽  
Performance Metrics ◽  
Large Displacement ◽  
Lumped Parameter Model ◽  
Thermal Actuator ◽  
Free Piston ◽  
Lumped Parameter ◽  
Peak Pressures ◽  
Actuator Design

A combustion-based mesoscale thermal actuator is proposed and its performance is studied in both open and closed cycle operations using a physics-based lumped-parameter model. The actuator design is unique as it implements a free-piston complaint architecture where the piston is free to move in a linear direction. Our objective is to study the actuator behavior in both the cycles to help identify the benefits and highlight the differences between the two cycles. The actuator is modeled as a spring-mass-damper system by taking an air standard cycle approach. Three observations are reported: (1) for nominal heat inputs (140 J/cycle), the actuator can produce large displacement strokes (16 cm) that is suitable for driving mesoscale robots; (2) the efficiency of the actuator depends on the heat input; and (3) for a specific heat input, both the open and closed cycles operate differently—with different stroke lengths, peak pressures, and thermal efficiencies. Our study reveals that the performance metrics of the actuator make it an ideal candidate for high speed, large force, and large displacement stroke related applications.

Transient Behavior of Seated Human Body During Input From Caudophalad Acceleration

2000 ◽  
Author(s):  
Paul C. Lam ◽  
P. Ruby Mawasha ◽  
Ted Conway
Keyword(s):  
Human Body ◽  
High Speed ◽  
Transient Behavior ◽  
Lumped Parameter Model ◽  
Load Factor ◽  
Time Duration ◽  
Bodily Injury ◽  
Lumped Parameter ◽  
Ejection Process ◽  
Short Time

Abstract The objective of this study, is to investigate the dynamic transient response of a four degree-of-freedom lumped parameter model of the seated human body subjected to caudocephalad loading (acceleration from tail to head). The caudocephalad loading used in the model simulated the ejection process of a seated pilot from a high-speed aircraft. During ejection, ejection velocities are high and are developed over short distances hence, the accelerations are also high (10–40 g’s). The model indicates that even though acceleration is applied over short time duration (typically less than 0.25 seconds), serious bodily injury can result due to high dynamic load factor for the frequency range of body resonances.

scholarly journals Investigation of Factors Influencing the Structural Vibration in Ball Bearings

2000 ◽  
Vol 6 (5) ◽  
pp. 321-331 ◽  
Author(s):  
Kapil Mehra ◽  
Kambiz Farhang ◽  
Jayanta Datta
Keyword(s):  
High Speed ◽  
Structural Vibration ◽  
Ball Bearings ◽  
Appreciable Change ◽  
Outer Race ◽  
Nonlinear Springs ◽  
Lumped Parameter ◽  
Intermittent Contact ◽  
Parameter Approach ◽  
Inner Race

Hertzian equation for elastic contact is utilized along with lumped parameter approach to obtain the equations that govern the structural vibration of ball bearings. The lumped parameter formulation is obtained by treating various elements with mass lumped at their centers of gravity and the contact as nonlinear springs with nonlinear spring rates.Effects of preload, ball rotational speed, and damping are studied using the formulation. It is found that in the presence of preload, irrespective of the load magnitude, contact is maintained with both the inner and the outer races. Hence, responses obtained with and without the check for ball/inner race and ball/outer race interferences are identical. In addition, no appreciable change is observed in the responses when the preload value is varied from 1 to 10 N. At high speed of operation, the balls are found to maintain contact with the outer ring, whereas intermittent contact with the inner ring occurs for brief periods of time. Introduction of lubricant is found to dampen the oscillations considerably.

A Lumped Parameter Model to Analyse the Dynamic Load Sharing in Planetary Gears with Planet Errors

2011 ◽  
Vol 86 ◽  
pp. 374-379 ◽  
Author(s):  
Xiao Yu Gu ◽  
Philippe Velex
Keyword(s):  
High Speed ◽  
Load Sharing ◽  
Lumped Parameter Model ◽  
Mesh Stiffness ◽  
Planetary Gears ◽  
Position Errors ◽  
Load Distributions ◽  
Lumped Parameter ◽  
Non Linear ◽  
Dynamic Load Sharing

A non-linear dynamic model of planetary gears is presented which accounts for planet position errors, time-varying non-linear mesh stiffness along with the interactions between deflections and instantaneous meshing conditions. The quasi-static load distributions agree well with the experimental results in the literature thus validating the contact simulation. Extensions towards high-speed behaviour are presented which show how dynamic effects may impact the instantaneous load sharing amongst the planets.

Integrated Piezoelectric Linear Motor for Vehicle Applications

2002 ◽  
Author(s):  
Mark Vaughan ◽  
Donald J. Leo
Keyword(s):  
Motor Performance ◽  
High Speed ◽  
Response Times ◽  
Fast Response ◽  
Linear Motor ◽  
Lumped Parameter Model ◽  
Moving Loads ◽  
Drive Frequency ◽  
Lumped Parameter ◽  
Motor Design

The focus of this research was to create a linear motor that could easily be packaged and still perform the same task of the current DC motor linear device. An incremental linear motor design was decided upon, for its flexibility in which the motor can be designed. To replace the current motor it was necessary to develop a high force, high speed incremental linear motor. To accomplish this task, piezoelectric actuators were utilized to drive the motor due their fast response times and high force capabilities. The desired overall objectives of the research is to create an incremental linear motor with the capability of moving loads up to one hundred pounds and produce a velocity well over one inch per second. To aid the design process a lumped parameter model was created to simulate the motor’s performance for any design parameter. Discrepancies occurred between the model and the actual motor performance for loads above 9.1 kilograms (20 pounds). The resulting model, however, was able to produce a good approximation of the motor’s performance for the unloaded and lightly loaded cases. The incremental linear motor produced a velocity of 4.9 mm/sec (0.2 in/sec) at a drive frequency of 50 Hz. The velocity of the motor was limited by the drive frequency that the amplifiers could produce. The motor was found to produce a stall load of 17 kilograms (38 pounds). The stall load of the design was severely limited by clearance losses.

A novel lumped-parameter model of crosstalk between vias in high-speed PCBS

2016 ◽  
Vol 58 (9) ◽  
pp. 2088-2090
Author(s):  
Weichang Cheng ◽  
Shen Xu ◽  
Juzheng Yu ◽  
Weifeng Sun
Keyword(s):  
High Speed ◽  
Lumped Parameter Model ◽  
Lumped Parameter

scholarly journals An Electromechanical Co-Simulation Model Based on Lumped Parameter Model of Ball Screw Feed Drive System

2018 ◽  
Vol 237 ◽  
pp. 03007
Author(s):  
Liang Luo ◽  
Weimin Zhang ◽  
Haonan Sui ◽  
Jürgen Fleischer
Keyword(s):  
Simulation Model ◽  
High Speed ◽  
Drive System ◽  
Lumped Parameter Model ◽  
Ball Screw ◽  
Feed System ◽  
Feed Drive ◽  
Lumped Parameter ◽  
Feed Drive System ◽  
Screw Feed

The continuous search for efficiency put forward higher requests to the machine tool for high speed and high acceleration, which makes the large-size and lightweight-designed feed drive system more likely to produce vibration during high-speed and high-acceleration feed operation. Ball screw feed system is the most widely used linear drive system in the field of industrial automation. Electromechanical Co-Simulation for ball screw feed drive dynamics is an important technique for solving vibration problems occurs in the feed motion. In view of the shortcomings of the current dynamic simulation model in the study of vibration of ball screw feed drive system, taking a ball screw feed drive system test bench as an example, an electromechanical co-simulation model based on the lumped parameter model of ball screw feed drive system was built up in this paper. Firstly, based on the axial and rotation vibration integrated dynamic modeling method of ball screws, the lumped parameter model of ball screw feed system was established. Secondly, through the integration of the simulation model of semi-closed-loop cascade control system and the lumped parameter model of ball screw feed drive system, an electromechanical co-simulation model was built up. Simulation result shows that, the co-simulation model of ball screw feed drive system can predict the vibration occurs in the feed operation caused by the servo controller, ball screw feed system or the coupling between them.

Hybrid Dynamic Modeling and Analysis of High-speed Thin-rimmed Gears

2021 ◽  
pp. 1-23
Author(s):  
Changzhao Liu ◽  
Yu Zhao ◽  
Yong Wang ◽  
Tie Zhang ◽  
Hanjie Jia
Keyword(s):  
Finite Element ◽  
Dynamic Model ◽  
High Speed ◽  
Degrees Of Freedom ◽  
Element Model ◽  
Lumped Parameter Model ◽  
Modeling And Analysis ◽  
Lumped Parameter ◽  
Proposed Model ◽  
Angular Displacements

Abstract In this study, a hybrid dynamic model of high-speed thin-rimmed gears is developed. In this model, the translational and angular displacements (including the rigid and vibration displacements) with a total of six degrees of freedom (DOFs) are selected as the generalized coordinates for each gear, and the meshing force distributions along the contact line and between the teeth are considered. Thus, the model can be implemented under stationary and non-stationary conditions. The condensed finite element models are developed with the centrifugal and inertia forces for gear bodies. This paper proposes a novel method to couple the lumped parameter model and condensed finite element model for the hybrid dynamic model system, which considers the variation of the meshing tooth during the gear operation, namely, the variations of the acting point of meshing force. Based on the model, the dynamic analysis of high-speed thin-rimmed gears is conducted under stationary speed and acceleration processes. The effects of the flexible gear body, high speed, and tooth errors on the system dynamics and tooth load distribution are investigated. The analysis results are also compared with the current reference and pure finite element method to validate the proposed model.

scholarly journals A multiscale sliding filament model of lymphatic muscle pumping

2021 ◽  
Author(s):  
Christopher J. Morris ◽  
David C. Zawieja ◽  
James E. Moore
Keyword(s):  
Smooth Muscle ◽  
Interstitial Fluid ◽  
Cellular Level ◽  
Calcium Oscillations ◽  
Lumped Parameter Model ◽  
Maximum Efficiency ◽  
Lumped Parameter ◽  
Muscle Types ◽  
Lymphatic Pumping ◽  
The Relationship

AbstractThe lymphatics maintain fluid balance by returning interstitial fluid to veins via contraction/compression of vessel segments with check valves. Disruption of lymphatic pumping can result in a condition called lymphedema with interstitial fluid accumulation. Lymphedema treatments are often ineffective, which is partially attributable to insufficient understanding of specialized lymphatic muscle lining the vessels. This muscle exhibits cardiac-like phasic contractions and smooth muscle-like tonic contractions to generate and regulate flow. To understand the relationship between this sub-cellular contractile machinery and organ-level pumping, we have developed a multiscale computational model of phasic and tonic contractions in lymphatic muscle and coupled it to a lymphangion pumping model. Our model uses the sliding filament model (Huxley in Prog Biophys Biophys Chem 7:255–318, 1957) and its adaptation for smooth muscle (Mijailovich in Biophys J 79(5):2667–2681, 2000). Multiple structural arrangements of contractile components and viscoelastic elements were trialed but only one provided physiologic results. We then coupled this model with our previous lumped parameter model of the lymphangion to relate results to experiments. We show that the model produces similar pressure, diameter, and flow tracings to experiments on rat mesenteric lymphatics. This model provides the first estimates of lymphatic muscle contraction energetics and the ability to assess the potential effects of sub-cellular level phenomena such as calcium oscillations on lymphangion outflow. The maximum efficiency value predicted (40%) is at the upper end of estimates for other muscle types. Spontaneous calcium oscillations during diastole were found to increase outflow up to approximately 50% in the range of frequencies and amplitudes tested.

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