scholarly journals Semiactive Vibration Control for Horizontal Axis Washing Machine

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Barış Can Yalçın ◽  
Haluk Erol
Keyword(s):  
Vibration Control ◽  
Dynamic Stability ◽  
Control Method ◽  
Angular Position ◽  
Angular Acceleration ◽  
Suspension System ◽  
Horizontal Axis ◽  
Washing Machine ◽  
Vibration Data ◽  
Semiactive Suspension

A semiactive vibration control method is developed to cope with the dynamic stability problem of a horizontal axis washing machine. This method is based on adjusting the maximum force values produced by the semiactive suspension elements considering a washing machine’s vibration data (three axis angular position and three axis angular acceleration values in time). Before actuation signals are received by the step motors of the friction dampers, vibration data are evaluated, and then, the step motors start to narrow or expand the radius of bracelets located on the dampers. This changes the damping properties of the damper in the suspension system, and thus, the semiactive suspension system absorbs unwanted vibrations and contributes to the dynamic stability of the washing machine. To evaluate the vibration data, the angular position and angular acceleration values in three axes are defined in a function, and the maximum forces produced by semiactive suspension elements are calculated according to the gradient of this function. The relation between the dynamic stability and the walking stability is also investigated. A motion (gyroscope and accelerometer) sensor is installed on the top-front panel of the washing machine because a mathematical model of a horizontal axis washing machine suggests that the walking behavior starts around this location under some assumptions, and therefore, calculating the vibrations occurring there is crucial. Semiactive damping elements are located under the left and right sides of the tub. The proposed method is tested during the spinning cycle of washing machine operation, increasing gradually from 200 rpm to 900 rpm, which produces the most challenging vibration patterns for dynamic stability. Moreover, the sound power levels produced by the washing machine are measured to evaluate the noise performance of the washing machine while the semiactive suspension system is controlled. The effectiveness of the proposed control method is shown through experimental results.

Angular Positioning and Vibration Control of a Slewing Flexible Control by Applying Smart Materials and Sliding Modes Control

2017 ◽  
Author(s):  
Frederic C. Janzen ◽  
Jose M. Balthazar ◽  
Angelo M. Tusset ◽  
Rodrigo T. Rocha ◽  
Jeferson Jose de Lima
Keyword(s):  
Vibration Control ◽  
Smart Materials ◽  
Position Control ◽  
Control Method ◽  
Angular Position ◽  
Dc Motor ◽  
Sliding Modes ◽  
Flexible Link ◽  
Positioning Control ◽  
Sma Actuators

Flexible links undergoing a slewing motion are widely found in aerospace structures such as satellites and robotic manipulators. In this kind of systems, the lighter the structure the better is its performance and more cost effective is the system. However, the positioning control of flexible structures is challenging because the flexibility may lead the system to vibrate in larger amplitudes, which makes the need of using actuators to control and reduce vibrations. An alternative for those actuators is the use of smart materials, as SMA (Shape Memory Alloys) to control vibrations of such structures. This work will present the angular positioning and vibration control of a flexible link. The angular position control is a torque driven by a DC motor controlled through a sliding modes control method. The system is considered as non-ideal, it means that the vibration of the flexible link accomplishes to the DC motor shaft. SMA actuators are coupled to the flexible link with the objective to reduce the vibration amplitudes and reducing so the settling time of the system. The SMA actuators are controlled through an electric voltage applied to its terminals by applying the Sliding modes control method. The dynamical equations of motion for the system are developed considering a dead zone nonlinearity of the DC motor and a phenomenological model for the SMA. The flexible link is modeled as a continuous structure and just the first vibration mode is analyzed. Numerical simulations results are presented to demonstrate the effectiveness of the sliding modes strategy for the positioning control of the DC motor and for the vibration suppression of the flexible link by using SMA actuators.

Modeling and Experimental Assessment of Suspension Dynamics of a Horizontal-Axis Washing Machine

1998 ◽  
Vol 120 (2) ◽  
pp. 534-543 ◽  
Author(s):  
O. S. Tu¨rkay ◽  
I. T. Su¨mer ◽  
A. K. Tugˇcu ◽  
B. Kiray
Keyword(s):  
Euler Method ◽  
Suspension System ◽  
Horizontal Axis ◽  
Washing Machine ◽  
Simulation Code ◽  
Rigid Body Dynamic ◽  
Shock Absorbers ◽  
Theoretical Predictions ◽  
Suspension Dynamics ◽  
Lift Off

In this paper a nonlinear time variant rigid body dynamic model of the suspension system of an horizontal-axis washing machine is derived using Newton-Euler method, programmed for simulation, and assessed experimentally. The model includes the shock absorbers, the non-linear stiffness of the bellows and also the decoupled spinup motor dynamics. The simulation model predicted the transient and steady-state vertical and horizontal amplitudes of the tub within acceptable errors for a prototype suspension system design. The lift-off and the sliding phenomena of the cabinet have been assessed experimentally using four triaxial piezoelectric force transducers. These were found to be in very good agreement with the theoretical predictions. The model and the simulation code are thus validated experimentally for suspension design optimization of horizontal-axis washing machines.

scholarly journals The double-delay reducing vibration control for five-degree-of-freedom half-vehicle model in idle condition

2019 ◽  
Vol 39 (1) ◽  
pp. 203-215
Author(s):  
Qingchang Wang ◽  
Chuanbo Ren ◽  
Jilei Zhou ◽  
Lei Zhang
Keyword(s):  
Time Delay ◽  
Feedback Control ◽  
Vibration Control ◽  
Angular Acceleration ◽  
Suspension System ◽  
Vehicle Body ◽  
Vehicle Suspension ◽  
Optimal Feedback ◽  
Delay Feedback Control ◽  
Vibration Performance

When running in idle condition, the vehicle has no speeds and road excitation, and the engine vertical self-vibration is the main excitation source. In this paper, a five-degree-of-freedom half-vehicle suspension model with double-delay feedback control is proposed to improve the vibration performance in idle condition. First, according to the system amplitude–frequency characteristic, the multiobjective function combining the vehicle body acceleration and pitching angular acceleration is established. Then, utilizing particle swarm optimization in optimizing and analyzing, the optimal feedback gains and time delays of the suspension system are obtained. Subsequently, a new frequency scanning method is utilized to analyze the stability of the controlled suspension system with the optimal feedback parameters. Finally, numerical simulations in the Matlab/Simulink environment are conducted to validate the performance of time-delay reducing vibration control on different engine feedback condition. Simulation results indicate that the active suspension with time-delay feedback control based on engine acceleration has better reducing vibration performance, and the root mean square of vehicle body and pitching angular acceleration are, respectively, reduced 87.37 and 80.01% than that without time delay. The research on vehicle suspension system with time-delay feedback control can improve the vibration performance effectively compared to the conventional one.

scholarly journals A Variable Parameter Ambient Vibration Control Method Based on Quasi-Zero Stiffness in Robotic Drilling Systems

Machines ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 67
Author(s):  
Laixi Zhang ◽  
Chenming Zhao ◽  
Feng Qian ◽  
Jaspreet Singh Dhupia ◽  
Mingliang Wu
Keyword(s):  
Vibration Control ◽  
Vibration Isolation ◽  
Control Method ◽  
Control Strategies ◽  
Equations Of Motion ◽  
Variable Parameter ◽  
Harmonic Balance Method ◽  
Variable Stiffness ◽  
Ambient Vibration ◽  
Robotic Drilling

Vibrations in the aircraft assembly building will affect the precision of the robotic drilling system. A variable stiffness and damping semiactive vibration control mechanism with quasi-zero stiffness characteristics is developed. The quasi-zero stiffness of the mechanism is realized by the parallel connection of four vertically arranged bearing springs and two symmetrical horizontally arranged negative stiffness elements. Firstly, the quasi-zero stiffness parameters of the mechanism at the static equilibrium position are obtained through analysis. Secondly, the harmonic balance method is used to deal with the differential equations of motion. The effects of every parameter on the displacement transmissibility are analyzed, and the variable parameter control strategies are proposed. Finally, the system responses of the passive and semiactive vibration isolation mechanisms to the segmental variable frequency excitations are compared through virtual prototype experiments. The results show that the frequency range of vibration isolation is widened, and the stability of the vibration control system is effectively improved without resonance through the semiactive vibration control method. It is of innovative significance for ambient vibration control in robotic drilling systems.

The Simulation Analysis of Semi-Active Suspension System in Vehicle Based on Sliding Mode Control with Varying Structure

2011 ◽  
Vol 216 ◽  
pp. 96-100
Author(s):  
Jing Jun Zhang ◽  
Wei Sha Han ◽  
Li Ya Cao ◽  
Rui Zhen Gao
Keyword(s):  
Control Method ◽  
Simulation Analysis ◽  
Reference Model ◽  
Sliding Mode ◽  
Tracking Error ◽  
Active Suspension ◽  
Suspension System ◽  
Sliding Mode Controller ◽  
Error Dynamics ◽  
Dynamic Quality

A sliding mode controller for semi-active suspension system of a quarter car is designed with sliding model varying structure control method. This controller chooses Skyhook as a reference model, and to force the tracking error dynamics between the reference model and the plant in an asymptotically stable sliding mode. An equal near rate is used to improve the dynamic quality of sliding mode motion. Simulation result shows that the stability of performance of the sliding-mode controller can effectively improve the driving smoothness and safety.

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