Stability analysis of a time-optimally controlled electrostatic suspension system and suspension experiments in a vacuum

2010 ◽  
Vol 225 (1) ◽  
pp. 88-100 ◽  
Author(s):  
T T Le ◽  
J U Jeon
Keyword(s):  
Low Cost ◽  
Electromagnetic Levitation ◽  
Dielectric Materials ◽  
Suspension System ◽  
System Stability ◽  
Suspension Systems ◽  
Control Scheme ◽  
Time Optimal ◽  
Bang Bang Control ◽  
Work First

Electrostatic suspension permits conductive, semiconductive, and dielectric materials to be supported without mechanical contact, in contrast to electromagnetic levitation by which only ferromagnetic materials can be levitated. To expand applications of electrostatic suspension systems, a low-cost electrostatic suspension system using a time optimal bang—bang control scheme where linear analogue high-voltage amplifiers that are costly and bulky are not employed has already been implemented. In this article, a time optimal bang—bang control scheme is used to stabilize the system like the previous work. First, the process to find the recoverable set for all the states in which a time optimal bang—bang control exists is described in detail. Then, the switching criterion for the suspension system is derived by using a backward integration technique and the system stability is theoretically investigated using Lyapunov's function as well. To experimentally verify the system stability in vacuum, suspension experiments are carried out with 3.5 in aluminium discs in a vacuum environment. Experiments in the atmosphere are also conducted for comparison with the results in the vacuum. The experimental results show that an aluminium disc has been stably suspended at a reference gap length of 300 μm in a vacuum environment.

A suspension system with quasi-zero stiffness characteristics and inerter nonlinear energy sink

2020 ◽  
pp. 107754632097290
Author(s):  
You-cheng Zeng ◽  
Hu Ding ◽  
Rong-Hua Du ◽  
Li-Qun Chen
Keyword(s):  
Integrated Control ◽  
Harmonic Approximation ◽  
Nonlinear Energy Sink ◽  
Suspension System ◽  
Degree Of Freedom ◽  
System Parameters ◽  
Suspension Systems ◽  
Control Scheme ◽  
Energy Sink ◽  
Nonlinear Energy

In this article, a novel vibration control scheme of suspension systems is proposed. It combines the advantages of quasi-zero stiffness isolator, nonlinear energy sink absorber, and inerter. This proposed scheme can achieve low transmissibility, low amplitude, and low additional weight and resolve the conflict between riding comfort and handling stability. Strong nonlinear vibration equations of a quarter-vehicle suspension system are established. It also presents the detailed process of high-order harmonic approximation to obtain steady-state responses. Moreover, approximate solutions are validated by a numerical method. Furthermore, based on riding comfort and handling stability, the following four suspension systems are evaluated and compared, namely, 2-degree-of-freedom quarter-vehicle model, 2-degree-of-freedom quarter-vehicle with quasi-zero stiffness isolator, 2-degree-of-freedom quarter-vehicle with inerter-nonlinear energy sink absorber, and 2-degree-of-freedom quarter-vehicle integrated control scheme with quasi-zero stiffness and inerter-nonlinear energy sink. It is found that the integrated control scheme with quasi-zero stiffness and inerter-nonlinear energy sink can significantly improve the riding comfort and handling stability at the same time. In addition, the effects of system parameters are studied carefully. The results show that based on the reasonable design of the control system parameters, better riding comfort and handling stability can be obtained. In short, this article provides a theoretical basis for integrating quasi-zero stiffness isolators and inerter-nonlinear energy sink absorbers to improve the riding comfort and handling stability.

scholarly journals The algorithm of adaptive control for active suspension systems using pole assign and cascade design method

2020 ◽  
Vol 9 (4) ◽  
pp. 271
Author(s):  
Chi Nguyen Van
Keyword(s):  
Control Method ◽  
Reference Model ◽  
Active Suspension ◽  
Suspension System ◽  
Control Force ◽  
Control Loop ◽  
The Road ◽  
Suspension Systems ◽  
Road Profile ◽  
Control Scheme

This paper presents the active suspension system (ASS) control method using the adaptive cascade control scheme. The control scheme is implemented by two control loops, the inner control loop and outer control loop are designed respectively. The inner control loop uses the pole assignment method in order to move the poles of the original system to desired poles respect to the required performance of the suspension system. To design the controller in the inner loop, the model without the noise caused by the road profile and velocity of the car is used. The outer control loop then designed with an adaptive mechanism calculates the active control force to compensate for the vibrations caused by the road profile and velocity of the car. The control force is determined by the error between states of the reference model and states of suspension systems, the reference model is the model of closed-loop with inner control loop without the noise. The simulation results implemented by using the practice date of the road profile show that the capability of oscillation decrease for ASS is quite efficient

Modeling of an Inertially Stabilized Camera System Using Gimbal Platform

2016 ◽  
Author(s):  
Gary Haggart ◽  
Vidya K. Nandikolla ◽  
Ruting Jia
Keyword(s):  
Low Cost ◽  
System Stability ◽  
Motor Drive ◽  
Performance Limits ◽  
Camera System ◽  
Control Scheme ◽  
Selection For ◽  
And Performance ◽  
Stabilized Platform ◽  
Inertially Stabilized Platform

This paper develops a camera gimbal platform for stabilization and tracking purposes. The main focus of this research is analytical modeling of an inertially stabilized platform with the prediction of the angular stability. The mechanical model of the platform includes, moment of inertia, motor drive, and performance of the gyro to measure the disturbances of the platform. The gimbal/motor system is developed and simulated and feedback control scheme is designed to stabilize and maintain the line of sight (LOS) for tracking purposes. The model integrates a PI2 controller using a PID-I approach for the system stability. The effect of vibration induced disturbance in the system is investigated to simulate the realistic behavior of an inertially stabilized platform. The simulation results of the four types of commercial gyros are presented to calculate the required values for stability purposes. The results from the simulation generated the performance limits chart describing the working condition of the low cost sensors vs the high cost sensors. As the vibration level increased, the performance of the highest quality sensor greatly decreased. This verifies the value and necessity of modeling and simulating to understand the component trade studies to ensure correct sensor selection for the desired application.

Hardware/Software Codesign of a Low-Cost Rate Control Scheme for H.264/AVC

2010 ◽  
Vol 20 (2) ◽  
pp. 250-261 ◽  
Author(s):  
Chih-Hung Kuo ◽  
Li-Chuan Chang ◽  
Kuan-Wei Fan ◽  
Bin-Da Liu
Keyword(s):  
Rate Control ◽  
Low Cost ◽  
Cost Rate ◽  
Control Scheme

scholarly journals Flyback Photovoltaic Micro-Inverter with a Low Cost and Simple Digital-Analog Control Scheme

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4239
Author(s):  
Salam J. Yaqoob ◽  
Adel Obed ◽  
Rana Zubo ◽  
Yasir I. A. Al-Yasir ◽  
Hussein Fadhel ◽  
...  
Keyword(s):  
Digital Signal Processor ◽  
Low Cost ◽  
Harmonic Distortion ◽  
Single Stage ◽  
System Component ◽  
Maximum Efficiency ◽  
System Efficiency ◽  
Control Scheme ◽  
The Cost ◽  
Micro Inverter

The single-stage flyback Photovoltaic (PV) micro-inverter is considered as a simple and small in size topology but requires expensive digital microcontrollers such as Field-Programmable Gate Array (FPGA) or Digital Signal Processor (DSP) to increase the system efficiency, this would increase the cost of the overall system. To solve this problem, based on a single-stage flyback structure, this paper proposed a low cost and simple analog-digital control scheme. This control scheme is implemented using a low cost ATMega microcontroller built in the Arduino Uno board and some analog operational amplifiers. First, the single-stage flyback topology is analyzed theoretically and then the design consideration is obtained. Second, a 120 W prototype was developed in the laboratory to validate the proposed control. To prove the effectiveness of this control, we compared the cost price, overall system efficiency, and THD values of the proposed results with the results obtained by the literature. So, a low system component, single power stage, cheap control scheme, and decent efficiency are achieved by the proposed system. Finally, the experimental results present that the proposed system has a maximum efficiency of 91%, with good values of the total harmonic distortion (THD) compared to the results of other authors.

scholarly journals Semi-Active Magnetic Levitation System for Education

2021 ◽  
Vol 11 (12) ◽  
pp. 5330
Author(s):  
Gisela Pujol-Vázquez ◽  
Alessandro N. Vargas ◽  
Saleh Mobayen ◽  
Leonardo Acho
Keyword(s):  
Pid Control ◽  
Magnetic Levitation ◽  
Low Cost ◽  
Control Scheme ◽  
Hands On ◽  
Levitation System ◽  
Magnetic Levitation System ◽  
And Control ◽  
Active Control Strategy ◽  
Cost Components

This paper describes how to construct a low-cost magnetic levitation system (MagLev). The MagLev has been intensively used in engineering education, allowing instructors and students to learn through hands-on experiences of essential concepts, such as electronics, electromagnetism, and control systems. Built from scratch, the MagLev depends only on simple, low-cost components readily available on the market. In addition to showing how to construct the MagLev, this paper presents a semi-active control strategy that seems novel when applied to the MagLev. Experiments performed in the laboratory provide comparisons of the proposed control scheme with the classical PID control. The corresponding real-time experiments illustrate both the effectiveness of the approach and the potential of the MagLev for education.

scholarly journals Online Adaptive Optimal Control of Vehicle Active Suspension Systems Using Single-Network Approximate Dynamic Programming

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Zhi-Jun Fu ◽  
Bin Li ◽  
Xiao-Bin Ning ◽  
Wei-Dong Xie
Keyword(s):  
Optimal Control ◽  
Dynamic Programming ◽  
Approximate Dynamic Programming ◽  
Control Method ◽  
Active Suspension ◽  
Suspension System ◽  
Lyapunov Theory ◽  
Adaptive Optimal Control ◽  
Suspension Systems ◽  
Optimal Control Method

In view of the performance requirements (e.g., ride comfort, road holding, and suspension space limitation) for vehicle suspension systems, this paper proposes an adaptive optimal control method for quarter-car active suspension system by using the approximate dynamic programming approach (ADP). Online optimal control law is obtained by using a single adaptive critic NN to approximate the solution of the Hamilton-Jacobi-Bellman (HJB) equation. Stability of the closed-loop system is proved by Lyapunov theory. Compared with the classic linear quadratic regulator (LQR) approach, the proposed ADP-based adaptive optimal control method demonstrates improved performance in the presence of parametric uncertainties (e.g., sprung mass) and unknown road displacement. Numerical simulation results of a sedan suspension system are presented to verify the effectiveness of the proposed control strategy.

scholarly journals Modeling the Non Linear Behavior of a Magnetic Fault Current Limiter

2015 ◽  
Vol 4 (3) ◽  
pp. 1 ◽  
Author(s):  
P. R. Wilson
Keyword(s):  
Large Scale ◽  
Low Cost ◽  
Behavioral Modeling ◽  
Fault Current ◽  
Fault Current Limiter ◽  
Intrinsic Properties ◽  
Automatic Behavior ◽  
Linear Behavior ◽  
Control Scheme ◽  
Fault Current Limiters

Fault Current Limiters are used in a wide array of applications from small circuit protection at low power levels to large scale high power applications which require superconductors and complex control circuitry. One advantage of  passive fault current limiters (FCL) is the automatic behavior that is dependent on the intrinsic properties of the circuit elements rather than on a complex feedback control scheme making this approach attractive for low cost applications and also where reliability is critical. This paper describes the behavioral modeling of a passive Magnetic FCL and its potential application in practical circuits.

LOW LOSS DIELECTRIC MATERIALS FOR HIGH FREQUENCY APPLICATIONS

2009 ◽  
Vol 23 (17) ◽  
pp. 3649-3654 ◽  
Author(s):  
MOHAN V. JACOB
Keyword(s):  
High Frequency ◽  
Room Temperature ◽  
Low Cost ◽  
Dielectric Materials ◽  
Dielectric Constants ◽  
Transmission Losses ◽  
Low Loss ◽  
Microwave Characterization ◽  
Materials Used ◽  
Low Temperature Electronics

The microwave properties of some of the low cost materials which can be used in high frequency applications with low transmission losses are investigated in this paper. One of the most accurate microwave characterization techniques, Split Post Dielectric Resonator technique (SPDR) is used for the experimental investigation. The dielectric constants of the 3 materials scrutinized at room temperature and at 10K are 3.65, 2.42, 3.61 and 3.58, 2.48, 3.59 respectively. The corresponding loss tangent values are 0.00370, 0.0015, 0.0042 and 0.0025, 0.0009, 0.0025. The high frequency transmission losses are comparable with many of the conventional materials used in low temperature electronics and hence these materials could be implemented in such applications.

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