Methods and Algorithms for Correcting Kinematic Equations in the Problem of Determining the Orientation of an Object

Algorithms of a strapdown inertial orientation system with an inertial measurement module consisting of a three-component gyroscope, accelerometer, and magnetometer are considered. The aim of the work is to improve the algorithms for processing sensor information to ensure the asymptotic stability of the system, tuning for the Schuler period and the low-pass filter with a given bandwidth. The kinematic Poisson equations with positional and integral-positional correction based on the information of accelerometers and magnetometers are considered. The stability and frequency characteristics of the system in relation to the sensor output signals are analyzed. It is shown that the positional correction in each channel does not allow you to adjust the system for the Schuler period. The integral-positional correction allows this adjustment, but in relation to the gyroscope signals, the system is a bandpass filter and does not suppress noise in the bandwidth. The advantages of using positional correction with cross-links in the sense of tuning the frequency characteristics of the system to the Sharper frequency and the third-order low-pass filter are shown. The analysis of the influence of angular velocities confirmed the asymptotic stability of the system with their changes in a given range. The results of mathematical modeling confirmed the compensation of errors in the initial orientation system display, the reduction of noise power in the estimates of the orientation angles in relation to the noise in the sensor signals, and the ability to configure the system for the Schuler period.

Download Full-text

Disturbance Elimination of Buck-Converter with Resonant LPF via ILQ Servo-System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.492.493 ◽

2014 ◽

Vol 492 ◽

pp. 493-498

Author(s):

Shuhei Shiina ◽

Sidshchadhaa Aumted ◽

Hiroshi Takami

Keyword(s):

Transfer Functions ◽

Design Method ◽

Servo System ◽

State Equation ◽

Buck Converter ◽

Linear Quadratic ◽

Pass Filter ◽

Low Pass Filter ◽

Low Pass ◽

The Stability

The proposed optimal control on the basis of both current and voltage of the buck-converter is designed to be based on Inverse Linear Quadratic (ILQ) design method with the resonant low pass filter, which eliminates the disturbance by appended disturbance compensator. The designed scheme is composed of the state equation, an optimal ILQ solution, the ILQ servo-system with the disturbance elimination, the optimal basic gain, the optimal condition, the transfer functions and the disturbance compensator. Our results show the proposed strategy is the stability and robust control and has been made to improve ILQ control for the disturbance elimination of the output response, which guarantees the optimal gains on the basis of polynomial pole assignment.

Download Full-text

COMPARISON OF FREQUENCY CHARACTERISTICS IN A DAMPER USING MAGNETIC FLUID, ER FLUID DISPERSING SMECTITE, AND MIXED ER MAGNETIC FLUID

International Journal of Modern Physics B ◽

10.1142/s0217979296001446 ◽

1996 ◽

Vol 10 (23n24) ◽

pp. 3001-3010 ◽

Cited By ~ 5

Author(s):

TOYOHISA FUJITA ◽

YASUHISA WADA ◽

GORO OBINATA ◽

YOICHI AKAGAMI ◽

SHINZO NISHIMURA ◽

...

Keyword(s):

Electric Fields ◽

Magnetic Fluid ◽

Silicone Oil ◽

Maxwell Model ◽

Frequency Characteristics ◽

Pass Filter ◽

Low Pass Filter ◽

Fluid Damper ◽

Low Pass ◽

Er Fluid

This paper presents a new type of damper using electro-rheological (ER) magnetic fluid for improving magnetic fluid damper and ER fluid damper. Silicone oil based magnetic fluid dispersing 10 nm size of magnetite, silicone oil based ER fluid dispersing 2 nm to 50 nm size of smectite and a mixture, that is, ER magnetic fluid have been used in a piston type damper. Dynamic visco-elasticities of these fluids have been measured by considering chain (cluster) formations. Next, frequency characteristics of transmissibility (magnification factor) and phase in damper have been compared with those fluids under magnetic field, electric field and both fields. The Voigt or Maxwell model can be applied in those dampers depending on amplitude. ER magnetic fluid has showed the decrease of amplitude ratios at resonance point and higher frequency at any amplitude under both magnetic and electric fields as low-pass filter.

Download Full-text

The stability analysis based on frequency response of integrated operational amplifier in linear low-pass filter circuit

2017 36th Chinese Control Conference (CCC) ◽

10.23919/chicc.2017.8029013 ◽

2017 ◽

Author(s):

Ming Zhang ◽

Guojun Liu ◽

Xi Chen

Keyword(s):

Stability Analysis ◽

Frequency Response ◽

Operational Amplifier ◽

Pass Filter ◽

Low Pass Filter ◽

Low Pass ◽

The Stability

Download Full-text

Motion Trajectory Tracking Method for Vehicle Steering Based on Dynamic Surface Control

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.220-223.1023 ◽

2012 ◽

Vol 220-223 ◽

pp. 1023-1027

Author(s):

Jun Gu ◽

Jun Fan ◽

Huan Shen

Keyword(s):

Trajectory Tracking ◽

Tracking System ◽

Lateral Position ◽

Dynamic Surface Control ◽

Dynamic Surface ◽

Pass Filter ◽

High Order Derivative ◽

Low Pass Filter ◽

Low Pass ◽

The Stability

Focus on the problem of steering trajectory tracking, a tracking control law based on dynamic surface is proposed. Other than existing methods, this paper considers combined lateral position and yaw synchronously control. The first order low pass filter is used to obtain the differential items of the lateral position and yaw, so as to eliminate the high order derivative from the final expression of the close loop law. This characteristic is very useful especially in real applications. The Lyapunov approach is employed to analysis the stability of the tracking system, and the convergence of the system is achieve. Simulation result validates the outstanding effectiveness of the proposed method for steering trajectory tracking.

Download Full-text

L 1 Adaptive Fractional Control Optimized by Genetic Algorithms with Application to Polyarticulated Robotic Systems

Mathematical Problems in Engineering ◽

10.1155/2021/5579541 ◽

2021 ◽

Vol 2021 ◽

pp. 1-14

Author(s):

Boutheina Maalej ◽

Rim Jallouli Khlif ◽

Chokri Mhiri ◽

Mohamed Habib Elleuch ◽

Nabil Derbel

Keyword(s):

Genetic Algorithms ◽

Adaptive Control ◽

Time Lag ◽

Pass Filter ◽

Low Pass Filter ◽

Control Approach ◽

Low Pass ◽

The Stability ◽

Fractional Control ◽

Model Reference Adaptive

Recently, an adaptive control approach has been proposed. This approach, named L 1 adaptive control, involves the insertion of a low-pass filter at the input of the Model Reference Adaptive Control (MRAC). This controller has been designed to overcome several limitations of classical adaptive controllers such as (i) the initialization of estimated parameters, (ii) the stability problems with high adaptation gains, and (iii) the appropriate parameter excitation. In this paper, a new design of the filter is presented, used for L 1 adaptive control, for which the desired performances are guaranteed (appropriate values of the control during start-up, a high filtering of noises, a reduced time lag, and a reduced energy consumption). Parameters of the new proposed filter have been optimised by genetic algorithms. The proposed L 1 adaptive fractional control is applied to a polyarticulated robotic system. Simulation results show the efficiency of the proposed control approach with respect to the classical L 1 adaptive control in the nominal case and in the presence of a multiplicative noise.

Download Full-text