On minimum step response rise time of linear low-pass systems under the constraint of a given noise bandwidth

Recovery-type auditory neurons in the anuran inferior colliculus (IC) respond with band-pass or low-pass selectivity for sinusoidal AM. These cells respond to each modulation cycle at slow AM rates and respond only at the onset of fast AM or pulse repetition rate (PRR) stimuli, failing to recover from the effects of early pulses. This selectivity is not altered by changes in pulse duty cycle. The recovery process is governed therefore by the interpulse interval and not the dimension of the gap between sound pulses. Most of these neurons preferred fast rise times, which is characteristic of the sound pulses in the calls of Hyla regilla and Rana pipiens, the two species selected for this study.

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Comparison of Polynomial Cam Profiles and Input Shaping for Driving Flexible Systems

Journal of Mechanical Design ◽

10.1115/1.4007797 ◽

2012 ◽

Vol 134 (12) ◽

Cited By ~ 4

Author(s):

Brice Pridgen ◽

William Singhose

Keyword(s):

Rise Time ◽

Laplace Transforms ◽

Experimental Results ◽

Input Shaping ◽

Flexible Systems ◽

Residual Vibration ◽

Alternative Method ◽

Cam Follower ◽

Low Pass ◽

Polynomial Profiles

Polynomial profiles can be used as reference commands to limit induced vibration in flexible systems. Due to their ease of design and low-pass filtering effects, polynomial profiles are often found in cam-follower systems. Polynomial profiles have also been used as smooth reference commands for automated machines. However, despite extensive work to develop and improve such profiles, inherent tradeoffs still exist between induced vibration, rise time, and ease of design. Input shaping is an alternative method for generating motion commands that reduce residual vibration. This paper compares polynomial profiles to input-shaped commands for the application of reducing vibration in flexible systems. Analyses using Laplace transforms reveal that input shapers suppress vibration at regularly spaced frequencies. However, polynomial profiles do not share this property. Simulations and experimental results show that input shaping improves rise time and reduces residual vibration in comparison to polynomial profiles.

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Design and Fabrication of a Piezoelectric Sensor for Weighing in Motion

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.483.154 ◽

2011 ◽

Vol 483 ◽

pp. 154-157 ◽

Cited By ~ 1

Author(s):

Li Bo Zhao ◽

Jian Qiang Liang ◽

Yu Long Zhao ◽

Jian Zhu Wang ◽

Wei Chen ◽

...

Keyword(s):

Rise Time ◽

Quartz Crystal ◽

Piezoelectric Effect ◽

Dynamic Test ◽

Piezoelectric Sensor ◽

Experimental Results ◽

Step Response ◽

Load Carrying ◽

Length Direction ◽

The Cost

Based on piezoelectric effect of quartz crystal, a piezoelectric sensor with the range of 150 kN has been developed for weighing in motion (WIM).The sensor consists of the sensitive elements and load-carrying beam. In order to decrease the cost and difficulty of processing of the load-carrying beam, separate structure of the load-carrying beam is designed with series bolts. Moreover, the preload on the sensitive elements can be adjust by the bolts, thus the sensitivity of the sensor also can be adjust and calibrated conveniently. The experimental results show the sensitivity of the sensor is about 1.32 PC/N, and the non-compliance of output along the length direction is less than 3.75%. The dynamic test shows the rise time of the step response is less than 0.1 ms that meet the requirement of WIM.

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Improving Elmore Model of RLC Networks for Applying to SWCNT Interconnects

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.110-116.5078 ◽

2011 ◽

Vol 110-116 ◽

pp. 5078-5084

Author(s):

Behrouz Behtoee ◽

Rahim Faez

Keyword(s):

Carbon Nanotube ◽

Closed Form ◽

Curve Fitting ◽

Rise Time ◽

Step Response ◽

Analytical Estimate ◽

Single Wall Carbon ◽

Closed Form Solutions ◽

Improved Accuracy ◽

First Time

Elmore delay has been widely used as an analytical estimate of the interconnect delays in the performance-driven synthesis and layout of VLSI routing topologies. In this paper, Closed-form solutions for the 50% delay, rise time and overshoots of the step response of distributed Single Wall Carbon Nanotube (SWCNT), which consists RC and RLC parts, are presented for the first time. The proposed approach retains both efficiency and simplicity of the equivalent Elmore model with significantly improved accuracy, through surface fitting (3D) instead of curve fitting (2D).

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Dynamic Compensation for Two-Axis Robot Wrist Force Sensors

Journal of Sensors ◽

10.1155/2013/357396 ◽

2013 ◽

Vol 2013 ◽

pp. 1-5 ◽

Cited By ~ 7

Author(s):

Junqing Ma ◽

Aiguo Song ◽

Dongcheng Pan

Keyword(s):

Force Sensor ◽

Compensation Method ◽

Step Response ◽

Order System ◽

Force Sensors ◽

Dynamic Compensation ◽

Pass Filter ◽

Low Pass Filter ◽

Low Pass ◽

Robot Wrist

To improve the dynamic characteristic of two-axis force sensors, a dynamic compensation method is proposed. The two-axis force sensor system is assumed to be a first-order system. The operation frequency of the system is expanded by a digital filter with backward difference network. To filter high-frequency noises, a low-pass filter is added after the dynamic compensation network. To avoid overcompensation, parameters of the proposed dynamic compensation method are defined by trial and error. Step response methods are utilized in dynamic calibration experiments. Compared to experiment data without compensation, the response time of the dynamic compensated data is reduced by 30%~40%. Experiments results demonstrate the effectiveness of our method.

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Optimum design of electron beam-semiconductor linear low-pass amplifiers—Part I: Bandwidth and rise time

IEEE Transactions on Electron Devices ◽

10.1109/t-ed.1973.17668 ◽

1973 ◽

Vol 20 (4) ◽

pp. 447-455 ◽

Cited By ~ 4

Author(s):

C.B. Norris

Keyword(s):

Electron Beam ◽

Optimum Design ◽

Rise Time ◽

Low Pass

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Multi-objective genetic algorithm optimization of linear proportional solenoid actuator

Journal of the Brazilian Society of Mechanical Sciences and Engineering ◽

10.1007/s40430-020-02768-7 ◽

2021 ◽

Vol 43 (2) ◽

Author(s):

Shi Jie Wang ◽

Zhi Dan Weng ◽

Bo Jin ◽

Hong Xu Cai

Keyword(s):

Genetic Algorithm ◽

Rise Time ◽

Optimization Method ◽

Step Response ◽

Design Parameters ◽

Shape Design ◽

Nonlinear Relationship ◽

Response Performance ◽

Conventional Type ◽

2D Model

AbstractLinear proportional solenoid (LPS) is widely applied in different linear motion control systems as the electromagnetic actuator since its high reliability and low cost. LPS is difficult to optimize by changing a single variable due to amounts of structural design parameters, and each design parameter has a nonlinear relationship with the static electromagnetic force. This paper aims to improve LPS’s push force and response performance through magnetostatic finite element analysis (FEA) by ANSYS MAXWELL. This study compares FEA 2D model, 3D model and measurement results underrated coil current to verify the accuracy of FEA 2D model. In order to reveal the nonlinear relationship between shape design parameters and electromagnet design objectives, this study compares the influence degree of each variable on each design objective by conventional type LPS 2D FEA model. And for the purpose of improving LPS’s push force and response performance, a multi-objective optimization method has been proposed in this study based on genetic algorithm (GA) and magnetostatic FEA 2D model for optimizing the shape design parameters. All the study results were validated in both static conditions and dynamic conditions. The comparison between manufactured optimal type and conventional type results shows that the static push force in working stroke is improved 30.1%, displacement step response rise time is reduced 5.2% and 43.4%, and force step response rise time is reduced 20.5% and 44.6% with different return spring stiffness. Above all, LPS static and dynamic performance has been improved directly and the validation of proposed optimization method is verified in this paper.

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