Comparison of Robust Input Shapers for Elimination of Residual Vibrations

2014 ◽  
Vol 490-491 ◽  
pp. 997-1002
Author(s):  
Çağlar Conker ◽  
Hakan Yavuz ◽  
Sadettin Kapucu ◽  
Mustafa Kaan Baltacioğlu ◽  
Hüseyi̇n Turan Arat ◽  
...  

Input shaping is a feedforward control technique for improving the settling time and positioning accuracy, while minimizing residual vibrations. Shaped command profiles are generated by convolving a sequence of impulses. To design an input shaping controller, estimates of the system natural frequency and damping ratio are required. However, real systems cannot be modeled exactly, making the robustness to modeling errors an important consideration. Many robust input shapers have been developed, but robust shapers typically have longer durations that slow the system response. This creates a compromise between shaper robustness and rise time. This paper analyses the compromise between shaper duration and robustness for several robust input shapers

1994 ◽  
Vol 116 (2) ◽  
pp. 654-659 ◽  
Author(s):  
W. Singhose ◽  
W. Seering ◽  
N. Singer

This paper describes a method for limiting vibration in flexible systems by shaping the input to the system. Unlike most previous input shaping strategies, this method does not require a precise system model or lengthy numerical computation; only estimates of the system natural frequency and damping ratio are required. The effectiveness of this method when there are errors in the system model is explored and quantified. Next, an algorithm is presented, which, given an upper bound on acceptable residual vibration amplitude, determines a shaping strategy that is insensitive to errors in the estimate of the natural frequency. Finally, performance predictions are compared to hardware experiments.


Author(s):  
Joshua Vaughan ◽  
Aika Yano ◽  
William Singhose

Input shaping is a control method that limits motion-induced oscillation in vibratory systems by intelligently shaping the reference command. As with any control method, the robustness of input shaping to parameter variations and modeling errors is an important consideration. For input shaping, there exists a fundamental compromise between robustness to such errors and system rise time. For all types of shapers, greater robustness requires a longer duration shaper, which degrades rise time. However, if a shaper is allowed to contain negative impulses, then the shaper duration may be shortened with only a small cost of robustness and possible high-mode excitation. This paper presents a thorough analysis of the compromise between shaper duration, robustness, and possible high-mode excitation for several negative input-shaping methods. In addition, a formulation for specified negative amplitude, specified insensitivity shapers is presented. These shapers provide a continuous spectrum of solutions for the duration/robustness/high-mode excitation trade-off. Experimental results from a portable bridge crane verify the theoretical predictions.


Robotica ◽  
2005 ◽  
Vol 24 (1) ◽  
pp. 95-103 ◽  
Author(s):  
Gürsel Alici ◽  
Sadettin Kapucu ◽  
Sedat Bayseç

This paper presents a robust input shaping technique that significantly reduces (almost eliminates) the residual vibration of manipulation systems typified by a flexible-jointed robot manipulator. The technique consists of two stages. In the first stage, a ramp function is superimposed onto the main trajectory to be preshaped. In the second stage, the outcome of the first stage is convolved with a sequence of two impulses. The robustness of the technique to the uncertainties in the system natural frequency and damping ratio are quantified through simulation and experimental evaluation. Simulation and experimental results demonstrate that the technique is not only effective in reducing the residual vibrations, but also it is robust to the uncertainties of as ∓35% from the ideal value of the system natural frequency. Further, it has been found that the proposed input shaping technique is insensitive to the uncertainties in the damping ratio. The results allow us to suggest that the proposed technique is versatile and robust enough to apply it to the motion design of any flexible-jointed manipulation system making a point-to-point motion.


2020 ◽  
Vol 7 (2) ◽  
pp. 127-134
Author(s):  
Safah Tasya Aprilyani ◽  
Irianto Irianto ◽  
Epyk Sunarno

Penggunaan kontrol sangat diperlukan dalam pengaturan kecepatan motor DC. Dalam pengaturan kecepatan motor DC, salah satu jenis kontrol yang digunakan adalah kontrol Proportional Integral (PI). Untuk 4 jenis metode pada kontrol PI yang digunakan adalah metode Ziegler Nichole, Chien Servo 1, Chien Regulator 1 dan perhitungan secara analitik yang telah diperoleh dari data yang sudah ada.  Namun kontrol dengan PI 4 metode yang digunakan  sebagai pembanding memiliki waktu respon kecepatan saat stabil cenderung lambat baik dari nilai settling time, rise time dan steady state. Maka dari itu dilakukan komparasi antara 4 metode kontrol PI dengan penggunaan kontrol fuzzy. Dalam membandingkan antara 4 metode kontrol PI dan kontrol fuzzy terdapat beberapa parameter sebagai perbandingan yaitu maximum overshoot, steady state, rise time dan settling time. Hasil dari perbandingan tersebut adalah kontrol fuzzy dapat menghasilkan performa lebih baik jika dibandingkan dengan 4 metode pada kontrol PI. Kontrol fuzzy memiliki nilai rise time sebesar 0,015 detik, nilai settling time sebesar 0,025 detik dengan kecepatan sebesar 2900 rpm serta error steady state sebesar 3,33% tanpa adanya overshoot dan osilasi.


JURNAL ELTEK ◽  
2018 ◽  
Vol 16 (2) ◽  
pp. 125
Author(s):  
Oktriza Melfazen

Buck converter idealnya mempunyai keluaran yang stabil, pemanfaatandaya rendah, mudah untuk diatur, antarmuka yang mudah dengan pirantiyang lain, ketahanan yang lebih tinggi terhadap perubahan kondisi alam.Beberapa teknik dikembangkan untuk memenuhi parameter buckconverter. Solusi paling logis untuk digunakan pada sistem ini adalahmetode kontrol digital.Penelitian ini menelaah uji performansi terhadap stabilitas tegangankeluaran buck converter yang dikontrol dengan Logika Fuzzy metodeMamdani. Rangkaian sistem terdiri dari sumber tegangan DC variable,sensor tegangan dan Buck Converter dengan beban resistif sebagaimasukan, mikrokontroler ATMega 8535 sebagai subsistem kontroldengan metode logika fuzzy dan LCD sebagai penampil keluaran.Dengan fungsi keanggotaan error, delta error dan keanggotaan keluaranmasing-masing sebanyak 5 bagian serta metode defuzzifikasi center ofgrafity (COG), didapat hasil rerata error 0,29% pada variable masukan18V–20V dan setpoint keluaran 15V, rise time (tr) = 0,14s ; settling time(ts) = 3,4s ; maximum over shoot (%OS) = 2,6 dan error steady state(ess) = 0,3.


2017 ◽  
Vol 139 (4) ◽  
Author(s):  
Samuel F. Asokanthan ◽  
Soroush Arghavan ◽  
Mohamed Bognash

Effect of stochastic fluctuations in angular velocity on the stability of two degrees-of-freedom ring-type microelectromechanical systems (MEMS) gyroscopes is investigated. The governing stochastic differential equations (SDEs) are discretized using the higher-order Milstein scheme in order to numerically predict the system response assuming the fluctuations to be white noise. Simulations via Euler scheme as well as a measure of largest Lyapunov exponents (LLEs) are employed for validation purposes due to lack of similar analytical or experimental data. The response of the gyroscope under different noise fluctuation magnitudes has been computed to ascertain the stability behavior of the system. External noise that affect the gyroscope dynamic behavior typically results from environment factors and the nature of the system operation can be exerted on the system at any frequency range depending on the source. Hence, a parametric study is performed to assess the noise intensity stability threshold for a number of damping ratio values. The stability investigation predicts the form of threshold fluctuation intensity dependence on damping ratio. Under typical gyroscope operating conditions, nominal input angular velocity magnitude and mass mismatch appear to have minimal influence on system stability.


2011 ◽  
Vol 418-420 ◽  
pp. 2095-2101 ◽  
Author(s):  
Zhi Wei Wang ◽  
Wan Hua Zhao ◽  
Bing Heng Lu

Stiffness and damping of hydrostatic guideways are calculated by small perturbation method based on Reynolds equation in dynamic regime. The hydrostatic guideway is considered as a system which consists of the mass, the spring and the damper. The effects of some main parameters on stiffness, damping and damping ratio are analyzed which include the supply pressure, the film thickness, the pad dimension, the pressure ratio, the lubricating oil volume and the lubricating oil viscosity. The relationships between the settling time of the hydrostatic guideways and these parameters are investigated under a step load. It is shown that the slide block returns to equilibrium without overshooting under a step load, and the amplitude of the block vibration has not a maximum value under a cyclic load, due to the large damping effect( ξ>1). In addition, the settling time can be shorten with the increase of the supply pressure, the film thickness and the lubricating oil volume, and also with the decrease of the pressure ratio and the lubricating oil viscosity. The settling time get the shortest value when recess parameter( α) is 0.55.


JURNAL ELTEK ◽  
2020 ◽  
Vol 18 (2) ◽  
pp. 48
Author(s):  
Achmad Afandi ◽  
Mila Fauziyah Fauziyah ◽  
Denda Dewatama

Perusahaan tahu di Indonesia pada umumnya, masih menggunakan cara manual, dalam pembuatannya khususnya pada proses penyaringan bubur kedelai yang membutuhkan waktu yang, lama. Hal tersebut didasarkan pada belum ditemukannya mesin pemeras bubur kedelai. Dewasa ini telah ditemukan inovasi mesin, pemeras bubur kedelai yang bisa meningkatkan kuantitas dan, kualitas produksi dibanding dengan cara manual. Penerapan, teknologinya adalah bubur kedelai diletakkan pada tabung, penyaring kemudian tabung tersebut diputar menggunakan motor, yang dihubungkan melalui fanbelt dan pulley. Ketika motor, diputar, tabung akan ikut berputar sehingga menimbulkan gerak, sentrifugal dimana air kedelai akan terpisah dari ampas. Kecepatan putar motor yang dikontrol adalah 750 rpm dengan, nilai Kp 0,108 , Ki 0,83 sehingga mendapatkan air sari kedelai, sebesar 1,3 liter dengan perbandingan 1 kg kedelai : 1 liter air. Parameter dari penerapan metode PI ini meliputi rise time 4 detik, settling time 4,5 detik, overshoot 0 dan error steady state 2,4%. Dengan penerapan metode PI maka hasil perasan kedelai dari, peyaringan menjadi semakin banyak dan waktu yang dibutuhkan 4 menit lebih singkat dibandingkan dengan cara konvensional.   Tofu companies in Indonesia generally still use manual methods in their manufacture, especially in the soybean slurry screening process which certainly has many disadvantages such as extortion time needed. This was based on the fact that there was no innovation in the soybean pulp squeezer. Currently, it has been found that innovations of soybean slurry machines can increase the quantity and quality of production compared to manual methods. The application of the technology is soybean slurry placed on the filter tube then the tube is rotated using a motor connected with fanbelt and pulley. When the motor is rotated, the tube will rotate, causing centrifugal motion where the soybean water will separate from the pulp. The speed of the motor controlled in 750 rpm with the Kp 0,108, Ki 0,83, to get soybean essence up to 1,3 liter within comparison 1 kg soybean : 1 liter water. The parameter PI method including rise time 4 second, settling time 4,5 second, overshoot 0 and error steady state 2,4%. By applying PI method, the result of filtering is 4 minute faster comparing with conventional method.


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