Homeostatic capability of rate-sensitive feedback system: mathematical model

1984 ◽  
Vol 247 (5) ◽  
pp. R927-R931
Author(s):  
M. Okamoto ◽  
K. Hayashi
Keyword(s):  
Mathematical Model ◽  
Feedback Control ◽  
Feedback System ◽  
Control Element ◽  
External Perturbations ◽  
Large Loop ◽  
Key Enzyme ◽  
Loop Feedback ◽  
Control Capability ◽  
The Mathematical Model

We have predicted the mathematical model of rate-sensitive feedback control system and have investigated its homeostatic capability by using computer simulations. The results are summarized as follows. By installing a cyclic enzyme system as feedback control element, we could assume the rate-sensitive feedback system at molecular level. This type of feedback had realistic constant-value control capability for external perturbations. This feedback system was more effective for the exclusion of perturbation than was the concentration-sensitive feedback. A large-loop feedback was more stable for perturbation than was short-loop feedback. In sequential feedback system, every key enzyme sensitive to feedback control had to vary the activity at same time for the system to keep homeostasis.

Small-Signal Equivalent Circuit Modeling and Controller Design of DC/DC Converter Based on Matlab

2014 ◽  
Vol 1070-1072 ◽  
pp. 1586-1591
Author(s):  
Xiao Long Xiao ◽  
Xiao Jun Lu ◽  
Jian Wei Yi ◽  
Xiao Hua Ding
Keyword(s):  
Mathematical Model ◽  
Control Strategy ◽  
Model Building ◽  
Controller Design ◽  
Dynamic Performance ◽  
Feedback System ◽  
Small Signal ◽  
Loop Feedback ◽  
And Control ◽  
The Mathematical Model

The model-building of DC/DC converter is the key to design the control of system. It is important to study DC/DC converter stability and dynamic performance. A small-signal model of buck/boost circuit was built by average state-space. By analyzing the transfer function of buck/boost circuit, a voltage closed-loop feedback system was designed. Building system of simulation circuit in the Matlab, the result of simulation shows the system has a good static and dynamic performance. It verifies the rationality of the mathematical model and control strategy. It verifies the rationality of the mathematical model and control strategy.

An Efficient Approach to Define the Input Stimuli to Suppress Epileptic Seizures Described by the Epileptor Model

2020 ◽  
Vol 30 (11) ◽  
pp. 2050062
Author(s):  
João Angelo Ferres Brogin ◽  
Jean Faber ◽  
Douglas Domingues Bueno
Keyword(s):  
Nonlinear Dynamics ◽  
Mathematical Model ◽  
Exact Solution ◽  
Feedback Control ◽  
Epileptic Seizures ◽  
Neural Dynamics ◽  
Practical Application ◽  
Control Gain ◽  
The World ◽  
The Mathematical Model

Epilepsy affects about 70 million people in the world. Every year, approximately 2.4 million people are diagnosed with epilepsy, two-thirds of them will not know the etiology of their disease, and 1% of these individuals will decease as a consequence of it. Due to the inherent complexity of predicting and explaining it, the mathematical model Epileptor was recently developed to reproduce seizure-like events, also providing insights to improve the understanding of the neural dynamics in the interictal and ictal periods, although the physics behind each parameter and variable of the model is not fully established in the literature. This paper introduces an approach to design a feedback-based controller for suppressing epileptic seizures described by Epileptor. Our work establishes how the nonlinear dynamics of this disorder can be written in terms of a combination of linear sub-models employing an exact solution. Additionally, we show how a feedback control gain can be computed to suppress seizures, as well as how specific shapes applied as input stimuli for this purpose can be obtained. The practical application of the approach is discussed and the results show that the proposed technique is promising for developing controllers in this field.

Development of an Artificial Muscle Using PVC Gel

2011 ◽  
Author(s):  
Minoru Hashimoto
Keyword(s):  
Mathematical Model ◽  
Position Control ◽  
Artificial Muscle ◽  
Experimental Results ◽  
Control Element ◽  
Control Law ◽  
Poly Vinyl Chloride ◽  
Contraction Type ◽  
The Mathematical Model ◽  
Good Agreement

A poly vinyl chloride (PVC) gel actuator shows great potential for use as an artificial muscle because of such positive characteristics as movement in the air, large deformation, and being light in weight. A bending type actuator using PVC gel was studied previously. In order to construct an artificial muscle it is necessary to compose an actuator which has the characteristics of contraction type deformation. In the present paper we propose an electrode arrangement for a contraction type actuator using PVC gel. Also, we investigate the characteristics of the proposed actuator experimentally and show the effectiveness of the actuator as an artificial muscle. The experimental results showed that the contraction strain of the actuator was about 14%, the response rate was 7Hz, and the output stress was 4kPa. In order to apply the artificial muscle as a control element, we build a linear mathematical model of the electronic and mechanical characteristics. Based on the mathematical model, we design a control law of the PVC gel actuator. The control law is applied to the position control of the artificial muscle experimentally. The experimental results showed a good agreement with the simulated results using the mathematical model and an excellent performance in position control.

Simulation Study of Active Vibration Control of Cantilever Beam by Using State and Output Feedback Control Laws

2013 ◽  
Author(s):  
S. M. Khot ◽  
Nitesh P. Yelve ◽  
Raj Nair
Keyword(s):  
Mathematical Model ◽  
Feedback Control ◽  
Vibration Control ◽  
Output Feedback ◽  
Active Vibration Control ◽  
Output Feedback Control ◽  
Full Model ◽  
Control Laws ◽  
Active Vibration ◽  
The Mathematical Model

Undesired noise and vibrations have a detrimental effect in many areas. Hence the control of vibrations has become a relevant technological challenge. Active vibration control of structures using smart materials especially is in vogue. It involves sensing the motion of the structure using sensors, generating a control signal using a controller and applying a control force on the structure using actuators. To design the control system of any vibrating structure, the mathematical model of the system is required. However, it is not possible, to theoretically construct the model of complex structures. On the other hand, it is relatively simpler to model such systems in an Finite Element (FE) environment like ANSYS©. This paper deals with the extraction of the mathematical model of a cantilever beam from its FEA model. This procedure of extraction is applicable to any mechanical system under dynamics study. Then again, the matrices thus formed are usually very large and require a lot of computational time to process. Hence an attempt is made to construct the reduced model of the system which approximates the actual model to the desired extent. In this paper, the full model of the beam is reduced by discarding those modes which do not contribute to the overall response on the basis of their dc gains in MATLAB©. It is found that the frequency and transient responses of the full and reduced models match closely. Hence the reduced model may be used to represent the system instead of the full model with reasonable accuracy. Design of controller is attempted using the theory of state and output feedback control laws. The controller is modeled by calculating the optimal control gain by formulating an algorithm to solve the equations involved. The transient and frequency responses of the controlled full model and reduced models are then plotted. The procedure for designing controller described in this paper may be extended to any real world system.

DETERMINATION OF PERFORMANCE INDICATORS OF THE TRUCK KrAZ-6510TE

2020 ◽  
pp. 19-26
Author(s):  
Olexandr Pavlenko ◽  
Serhii Dun ◽  
Maksym Skliar
Keyword(s):  
Mathematical Model ◽  
Surface Friction ◽  
Building Structures ◽  
Maximum Torque ◽  
Military Equipment ◽  
Military Vehicles ◽  
Force Magnitude ◽  
Vehicle Mobility ◽  
The Mathematical Model

In any economy there is a need for the bulky goods transportation which cannot be divided into smaller parts. Such cargoes include building structures, elements of industrial equipment, tracked or wheeled construction and agricultural machinery, heavy armored military vehicles. In any case, tractor-semitrailer should provide fast delivery of goods with minimal fuel consumption. In order to guarantee the goods delivery, tractor-semitrailers must be able to overcome the existing roads broken grade and be capable to tow a semi-trailer in off-road conditions. These properties are especially important for military equipment transportation. The important factor that determines a tractor-semitrailer mobility is its gradeability. The purpose of this work is to improve a tractor-semitrailer mobility with tractor units manufactured at PJSC “AutoKrAZ” by increasing the tractor-semitrailer gradeability. The customer requirements for a new tractor are determined by the maximizing the grade to 18°. The analysis of the characteristics of modern tractor-semitrailers for heavy haulage has shown that the highest rate of this grade is 16.7°. The factors determining the limiting gradeability value were analyzed, based on the tractor-semitrailer with a KrAZ-6510TE tractor and a semi-trailer with a full weight of 80 t. It has been developed a mathematical model to investigate the tractor and semi-trailer axles vertical reactions distribution on the tractor-semitrailer friction performances. The mathematical model has allowed to calculate the gradeability value that the tractor-semitrailer can overcome in case of wheels and road surface friction value and the tractive force magnitude from the engine. The mathematical model adequacy was confirmed by comparing the calculations results with the data of factory tests. The analysis showed that on a dry road the KrAZ-6510TE tractor with a 80 t gross weight semitrailer is capable to climb a gradient of 14,35 ° with its coupling mass full use condition. The engine's maximum torque allows the tractor-semitrailer to overcome a gradient of 10.45° It has been determined the ways to improve the design of the KrAZ-6510TE tractor to increase its gradeability. Keywords: tractor, tractor-semitrailer vehicle mobility, tractor-semitrailer vehicle gradeability.

Sign in / Sign up

Export Citation Format

Share Document